Cairo 1.12.14

Change-Id: Ibc39e63896ec42cab29fbbbf615a46f2d58319a8
Signed-off-by: hk57.kim <hk57.kim@samsung.com>

1 files changed, 5076 insertions, 0 deletions

diff --git a/src/cairo-pattern.c b/src/cairo-pattern.c
new file mode 100755
index 000000000..4d6094ba2
--- /dev/null
+++ b/src/cairo-pattern.c
@@ -0,0 +1,5076 @@
+/* -*- Mode: c; c-basic-offset: 4; indent-tabs-mode: t; tab-width: 8; -*- */
+/* cairo - a vector graphics library with display and print output
+ *
+ * Copyright © 2004 David Reveman
+ * Copyright © 2005 Red Hat, Inc.
+ *
+ * Permission to use, copy, modify, distribute, and sell this software
+ * and its documentation for any purpose is hereby granted without
+ * fee, provided that the above copyright notice appear in all copies
+ * and that both that copyright notice and this permission notice
+ * appear in supporting documentation, and that the name of David
+ * Reveman not be used in advertising or publicity pertaining to
+ * distribution of the software without specific, written prior
+ * permission. David Reveman makes no representations about the
+ * suitability of this software for any purpose.  It is provided "as
+ * is" without express or implied warranty.
+ *
+ * DAVID REVEMAN DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS
+ * SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
+ * FITNESS, IN NO EVENT SHALL DAVID REVEMAN BE LIABLE FOR ANY SPECIAL,
+ * INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER
+ * RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
+ * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR
+ * IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ *
+ * Authors: David Reveman <davidr@novell.com>
+ *	    Keith Packard <keithp@keithp.com>
+ *	    Carl Worth <cworth@cworth.org>
+ */
+
+#include "cairoint.h"
+
+#include "cairo-array-private.h"
+#include "cairo-error-private.h"
+#include "cairo-freed-pool-private.h"
+#include "cairo-image-surface-private.h"
+#include "cairo-list-inline.h"
+#include "cairo-path-private.h"
+#include "cairo-pattern-private.h"
+#include "cairo-recording-surface-inline.h"
+#include "cairo-surface-snapshot-inline.h"
+
+#include <float.h>
+
+#define PIXMAN_MAX_INT ((pixman_fixed_1 >> 1) - pixman_fixed_e) /* need to ensure deltas also fit */
+
+/**
+ * SECTION:cairo-pattern
+ * @Title: cairo_pattern_t
+ * @Short_Description: Sources for drawing
+ * @See_Also: #cairo_t, #cairo_surface_t
+ *
+ * #cairo_pattern_t is the paint with which cairo draws.
+ * The primary use of patterns is as the source for all cairo drawing 
+ * operations, although they can also be used as masks, that is, as the 
+ * brush too.
+ *
+ * A cairo pattern is created by using one of the many constructors,
+ * of the form
+ * <function>cairo_pattern_create_<emphasis>type</emphasis>()</function>
+ * or implicitly through
+ * <function>cairo_set_source_<emphasis>type</emphasis>()</function>
+ * functions.
+ **/
+
+static freed_pool_t freed_pattern_pool[5];
+
+static const cairo_solid_pattern_t _cairo_pattern_nil = {
+    {
+      CAIRO_REFERENCE_COUNT_INVALID,	/* ref_count */
+      CAIRO_STATUS_NO_MEMORY,		/* status */
+      { 0, 0, 0, NULL },		/* user_data */
+      { NULL, NULL },			/* observers */
+
+      CAIRO_PATTERN_TYPE_SOLID,		/* type */
+      CAIRO_FILTER_DEFAULT,		/* filter */
+      CAIRO_EXTEND_GRADIENT_DEFAULT,	/* extend */
+      FALSE,				/* has component alpha */
+      { 1., 0., 0., 1., 0., 0., },	/* matrix */
+      1.0                               /* opacity */
+    }
+};
+
+static const cairo_solid_pattern_t _cairo_pattern_nil_null_pointer = {
+    {
+      CAIRO_REFERENCE_COUNT_INVALID,	/* ref_count */
+      CAIRO_STATUS_NULL_POINTER,	/* status */
+      { 0, 0, 0, NULL },		/* user_data */
+      { NULL, NULL },			/* observers */
+
+      CAIRO_PATTERN_TYPE_SOLID,		/* type */
+      CAIRO_FILTER_DEFAULT,		/* filter */
+      CAIRO_EXTEND_GRADIENT_DEFAULT,	/* extend */
+      FALSE,				/* has component alpha */
+      { 1., 0., 0., 1., 0., 0., },	/* matrix */
+      1.0                               /* opacity */
+    }
+};
+
+const cairo_solid_pattern_t _cairo_pattern_black = {
+    {
+      CAIRO_REFERENCE_COUNT_INVALID,	/* ref_count */
+      CAIRO_STATUS_SUCCESS,		/* status */
+      { 0, 0, 0, NULL },		/* user_data */
+      { NULL, NULL },			/* observers */
+
+      CAIRO_PATTERN_TYPE_SOLID,		/* type */
+      CAIRO_FILTER_NEAREST,		/* filter */
+      CAIRO_EXTEND_REPEAT,		/* extend */
+      FALSE,				/* has component alpha */
+      { 1., 0., 0., 1., 0., 0., },	/* matrix */
+      1.0                               /* opacity */
+    },
+    { 0., 0., 0., 1., 0, 0, 0, 0xffff },/* color (double rgba, short rgba) */
+};
+
+const cairo_solid_pattern_t _cairo_pattern_clear = {
+    {
+      CAIRO_REFERENCE_COUNT_INVALID,	/* ref_count */
+      CAIRO_STATUS_SUCCESS,		/* status */
+      { 0, 0, 0, NULL },		/* user_data */
+      { NULL, NULL },			/* observers */
+
+      CAIRO_PATTERN_TYPE_SOLID,		/* type */
+      CAIRO_FILTER_NEAREST,		/* filter */
+      CAIRO_EXTEND_REPEAT,		/* extend */
+      FALSE,				/* has component alpha */
+      { 1., 0., 0., 1., 0., 0., },	/* matrix */
+      1.0,                              /* opacity */
+    },
+    { 0., 0., 0., 0., 0, 0, 0, 0 },/* color (double rgba, short rgba) */
+};
+
+const cairo_solid_pattern_t _cairo_pattern_white = {
+    {
+      CAIRO_REFERENCE_COUNT_INVALID,	/* ref_count */
+      CAIRO_STATUS_SUCCESS,		/* status */
+      { 0, 0, 0, NULL },		/* user_data */
+      { NULL, NULL },			/* observers */
+
+      CAIRO_PATTERN_TYPE_SOLID,		/* type */
+      CAIRO_FILTER_NEAREST,		/* filter */
+      CAIRO_EXTEND_REPEAT,		/* extend */
+      FALSE,				/* has component alpha */
+      { 1., 0., 0., 1., 0., 0., },	/* matrix */
+      1.0                               /* opacity */
+    },
+    { 1., 1., 1., 1., 0xffff, 0xffff, 0xffff, 0xffff },/* color (double rgba, short rgba) */
+};
+
+static void
+_cairo_pattern_notify_observers (cairo_pattern_t *pattern,
+				 unsigned int flags)
+{
+    cairo_pattern_observer_t *pos;
+
+    cairo_list_foreach_entry (pos, cairo_pattern_observer_t, &pattern->observers, link)
+	pos->notify (pos, pattern, flags);
+}
+
+/**
+ * _cairo_pattern_set_error:
+ * @pattern: a pattern
+ * @status: a status value indicating an error
+ *
+ * Atomically sets pattern->status to @status and calls _cairo_error;
+ * Does nothing if status is %CAIRO_STATUS_SUCCESS.
+ *
+ * All assignments of an error status to pattern->status should happen
+ * through _cairo_pattern_set_error(). Note that due to the nature of
+ * the atomic operation, it is not safe to call this function on the nil
+ * objects.
+ *
+ * The purpose of this function is to allow the user to set a
+ * breakpoint in _cairo_error() to generate a stack trace for when the
+ * user causes cairo to detect an error.
+ **/
+static cairo_status_t
+_cairo_pattern_set_error (cairo_pattern_t *pattern,
+			  cairo_status_t status)
+{
+    if (status == CAIRO_STATUS_SUCCESS)
+	return status;
+
+    /* Don't overwrite an existing error. This preserves the first
+     * error, which is the most significant. */
+    _cairo_status_set_error (&pattern->status, status);
+
+    return _cairo_error (status);
+}
+
+void
+_cairo_pattern_init (cairo_pattern_t *pattern, cairo_pattern_type_t type)
+{
+#if HAVE_VALGRIND
+    switch (type) {
+    case CAIRO_PATTERN_TYPE_SOLID:
+	VALGRIND_MAKE_MEM_UNDEFINED (pattern, sizeof (cairo_solid_pattern_t));
+	break;
+    case CAIRO_PATTERN_TYPE_SURFACE:
+	VALGRIND_MAKE_MEM_UNDEFINED (pattern, sizeof (cairo_surface_pattern_t));
+	break;
+    case CAIRO_PATTERN_TYPE_LINEAR:
+	VALGRIND_MAKE_MEM_UNDEFINED (pattern, sizeof (cairo_linear_pattern_t));
+	break;
+    case CAIRO_PATTERN_TYPE_RADIAL:
+	VALGRIND_MAKE_MEM_UNDEFINED (pattern, sizeof (cairo_radial_pattern_t));
+	break;
+    case CAIRO_PATTERN_TYPE_MESH:
+	VALGRIND_MAKE_MEM_UNDEFINED (pattern, sizeof (cairo_mesh_pattern_t));
+	break;
+    case CAIRO_PATTERN_TYPE_RASTER_SOURCE:
+	break;
+    }
+#endif
+
+    pattern->type      = type;
+    pattern->status    = CAIRO_STATUS_SUCCESS;
+
+    /* Set the reference count to zero for on-stack patterns.
+     * Callers needs to explicitly increment the count for heap allocations. */
+    CAIRO_REFERENCE_COUNT_INIT (&pattern->ref_count, 0);
+
+    _cairo_user_data_array_init (&pattern->user_data);
+
+    if (type == CAIRO_PATTERN_TYPE_SURFACE ||
+	type == CAIRO_PATTERN_TYPE_RASTER_SOURCE)
+	pattern->extend = CAIRO_EXTEND_SURFACE_DEFAULT;
+    else
+	pattern->extend = CAIRO_EXTEND_GRADIENT_DEFAULT;
+
+    pattern->filter    = CAIRO_FILTER_DEFAULT;
+    pattern->opacity   = 1.0;
+
+    pattern->has_component_alpha = FALSE;
+
+    cairo_matrix_init_identity (&pattern->matrix);
+
+    cairo_list_init (&pattern->observers);
+
+    pattern->x_sigma = 0.0f;
+    pattern->y_sigma = 0.0;
+    pattern->x_radius = 0;
+    pattern->y_radius = 0;
+    pattern->convolution_matrix = NULL;
+    pattern->convolution_changed = FALSE;
+
+    memset (&pattern->shadow, 0, sizeof (cairo_shadow_t));
+}
+
+static cairo_status_t
+_cairo_gradient_pattern_init_copy (cairo_gradient_pattern_t	  *pattern,
+				   const cairo_gradient_pattern_t *other)
+{
+    if (CAIRO_INJECT_FAULT ())
+	return _cairo_error (CAIRO_STATUS_NO_MEMORY);
+
+    if (other->base.type == CAIRO_PATTERN_TYPE_LINEAR)
+    {
+	cairo_linear_pattern_t *dst = (cairo_linear_pattern_t *) pattern;
+	cairo_linear_pattern_t *src = (cairo_linear_pattern_t *) other;
+
+	*dst = *src;
+    }
+    else
+    {
+	cairo_radial_pattern_t *dst = (cairo_radial_pattern_t *) pattern;
+	cairo_radial_pattern_t *src = (cairo_radial_pattern_t *) other;
+
+	*dst = *src;
+    }
+
+    if (other->stops == other->stops_embedded)
+	pattern->stops = pattern->stops_embedded;
+    else if (other->stops)
+    {
+	pattern->stops = _cairo_malloc_ab (other->stops_size,
+					   sizeof (cairo_gradient_stop_t));
+	if (unlikely (pattern->stops == NULL)) {
+	    pattern->stops_size = 0;
+	    pattern->n_stops = 0;
+	    return _cairo_pattern_set_error (&pattern->base, CAIRO_STATUS_NO_MEMORY);
+	}
+
+	memcpy (pattern->stops, other->stops,
+		other->n_stops * sizeof (cairo_gradient_stop_t));
+    }
+
+    return CAIRO_STATUS_SUCCESS;
+}
+
+static cairo_status_t
+_cairo_mesh_pattern_init_copy (cairo_mesh_pattern_t       *pattern,
+			       const cairo_mesh_pattern_t *other)
+{
+    void *data = NULL;
+    *pattern = *other;
+
+    _cairo_array_init (&pattern->patches,  sizeof (cairo_mesh_patch_t));
+    data = _cairo_array_index_const (&other->patches, 0);
+    if (data == NULL)
+	return CAIRO_STATUS_NULL_POINTER;
+    return _cairo_array_append_multiple (&pattern->patches,
+					 data,
+					 _cairo_array_num_elements (&other->patches));
+}
+
+cairo_status_t
+_cairo_pattern_init_copy (cairo_pattern_t	*pattern,
+			  const cairo_pattern_t *other)
+{
+    cairo_status_t status;
+
+    if (other->status)
+	return _cairo_pattern_set_error (pattern, other->status);
+
+    switch (other->type) {
+    case CAIRO_PATTERN_TYPE_SOLID: {
+	cairo_solid_pattern_t *dst = (cairo_solid_pattern_t *) pattern;
+	cairo_solid_pattern_t *src = (cairo_solid_pattern_t *) other;
+
+	VG (VALGRIND_MAKE_MEM_UNDEFINED (pattern, sizeof (cairo_solid_pattern_t)));
+
+	*dst = *src;
+    } break;
+    case CAIRO_PATTERN_TYPE_SURFACE: {
+	cairo_surface_pattern_t *dst = (cairo_surface_pattern_t *) pattern;
+	cairo_surface_pattern_t *src = (cairo_surface_pattern_t *) other;
+
+	VG (VALGRIND_MAKE_MEM_UNDEFINED (pattern, sizeof (cairo_surface_pattern_t)));
+
+	*dst = *src;
+	cairo_surface_reference (dst->surface);
+    } break;
+    case CAIRO_PATTERN_TYPE_LINEAR:
+    case CAIRO_PATTERN_TYPE_RADIAL: {
+	cairo_gradient_pattern_t *dst = (cairo_gradient_pattern_t *) pattern;
+	cairo_gradient_pattern_t *src = (cairo_gradient_pattern_t *) other;
+
+	if (other->type == CAIRO_PATTERN_TYPE_LINEAR) {
+	    VG (VALGRIND_MAKE_MEM_UNDEFINED (pattern, sizeof (cairo_linear_pattern_t)));
+	} else {
+	    VG (VALGRIND_MAKE_MEM_UNDEFINED (pattern, sizeof (cairo_radial_pattern_t)));
+	}
+
+	status = _cairo_gradient_pattern_init_copy (dst, src);
+	if (unlikely (status))
+	    return status;
+
+    } break;
+    case CAIRO_PATTERN_TYPE_MESH: {
+	cairo_mesh_pattern_t *dst = (cairo_mesh_pattern_t *) pattern;
+	cairo_mesh_pattern_t *src = (cairo_mesh_pattern_t *) other;
+
+	VG (VALGRIND_MAKE_MEM_UNDEFINED (pattern, sizeof (cairo_mesh_pattern_t)));
+
+	status = _cairo_mesh_pattern_init_copy (dst, src);
+	if (unlikely (status))
+	    return status;
+
+    } break;
+
+    case CAIRO_PATTERN_TYPE_RASTER_SOURCE: {
+	status = _cairo_raster_source_pattern_init_copy (pattern, other);
+	if (unlikely (status))
+	    return status;
+    } break;
+    }
+
+    /* The reference count and user_data array are unique to the copy. */
+    CAIRO_REFERENCE_COUNT_INIT (&pattern->ref_count, 0);
+    _cairo_user_data_array_init (&pattern->user_data);
+
+    /* make separate copy of convolution matrix */
+    if (other->convolution_matrix) {
+        int col = 2 * other->x_radius + 1;
+        int row = 2 * other->y_radius + 1;
+        int size = row * col;
+
+        pattern->convolution_matrix = _cairo_malloc_ab (size, sizeof(double));
+	if (pattern->convolution_matrix == NULL)
+	    return CAIRO_STATUS_NO_MEMORY;
+
+        memcpy (pattern->convolution_matrix, other->convolution_matrix,
+                sizeof (double) * size);
+    }
+
+    return CAIRO_STATUS_SUCCESS;
+}
+
+void
+_cairo_pattern_init_static_copy (cairo_pattern_t	*pattern,
+				 const cairo_pattern_t *other)
+{
+    int size;
+
+    assert (other->status == CAIRO_STATUS_SUCCESS);
+
+    switch (other->type) {
+    default:
+	ASSERT_NOT_REACHED;
+    case CAIRO_PATTERN_TYPE_SOLID:
+	size = sizeof (cairo_solid_pattern_t);
+	break;
+    case CAIRO_PATTERN_TYPE_SURFACE:
+	size = sizeof (cairo_surface_pattern_t);
+	break;
+    case CAIRO_PATTERN_TYPE_LINEAR:
+	size = sizeof (cairo_linear_pattern_t);
+	break;
+    case CAIRO_PATTERN_TYPE_RADIAL:
+	size = sizeof (cairo_radial_pattern_t);
+	break;
+    case CAIRO_PATTERN_TYPE_MESH:
+	size = sizeof (cairo_mesh_pattern_t);
+	break;
+    case CAIRO_PATTERN_TYPE_RASTER_SOURCE:
+	size = sizeof (cairo_raster_source_pattern_t);
+	break;
+    }
+
+    memcpy (pattern, other, size);
+
+    CAIRO_REFERENCE_COUNT_INIT (&pattern->ref_count, 0);
+    _cairo_user_data_array_init (&pattern->user_data);
+}
+
+cairo_status_t
+_cairo_pattern_init_snapshot (cairo_pattern_t       *pattern,
+			      const cairo_pattern_t *other)
+{
+    cairo_status_t status;
+
+    /* We don't bother doing any fancy copy-on-write implementation
+     * for the pattern's data. It's generally quite tiny. */
+    status = _cairo_pattern_init_copy (pattern, other);
+    if (unlikely (status))
+	return status;
+
+    /* But we do let the surface snapshot stuff be as fancy as it
+     * would like to be. */
+    if (pattern->type == CAIRO_PATTERN_TYPE_SURFACE) {
+	cairo_surface_pattern_t *surface_pattern =
+	    (cairo_surface_pattern_t *) pattern;
+	cairo_surface_t *surface = surface_pattern->surface;
+
+	surface_pattern->surface = _cairo_surface_snapshot (surface);
+
+	cairo_surface_destroy (surface);
+
+	status = surface_pattern->surface->status;
+    } else if (pattern->type == CAIRO_PATTERN_TYPE_RASTER_SOURCE)
+	status = _cairo_raster_source_pattern_snapshot (pattern);
+
+    return status;
+}
+
+void
+_cairo_pattern_fini (cairo_pattern_t *pattern)
+{
+    _cairo_user_data_array_fini (&pattern->user_data);
+
+    switch (pattern->type) {
+    case CAIRO_PATTERN_TYPE_SOLID:
+	break;
+    case CAIRO_PATTERN_TYPE_SURFACE: {
+	cairo_surface_pattern_t *surface_pattern =
+	    (cairo_surface_pattern_t *) pattern;
+
+	cairo_surface_destroy (surface_pattern->surface);
+    } break;
+    case CAIRO_PATTERN_TYPE_LINEAR:
+    case CAIRO_PATTERN_TYPE_RADIAL: {
+	cairo_gradient_pattern_t *gradient =
+	    (cairo_gradient_pattern_t *) pattern;
+
+	if (gradient->stops && gradient->stops != gradient->stops_embedded)
+	    free (gradient->stops);
+    } break;
+    case CAIRO_PATTERN_TYPE_MESH: {
+	cairo_mesh_pattern_t *mesh =
+	    (cairo_mesh_pattern_t *) pattern;
+
+	_cairo_array_fini (&mesh->patches);
+    } break;
+    case CAIRO_PATTERN_TYPE_RASTER_SOURCE:
+	_cairo_raster_source_pattern_finish (pattern);
+	break;
+    }
+
+    if (pattern->convolution_matrix)
+        free (pattern->convolution_matrix);
+
+#if HAVE_VALGRIND
+    switch (pattern->type) {
+    case CAIRO_PATTERN_TYPE_SOLID:
+	VALGRIND_MAKE_MEM_NOACCESS (pattern, sizeof (cairo_solid_pattern_t));
+	break;
+    case CAIRO_PATTERN_TYPE_SURFACE:
+	VALGRIND_MAKE_MEM_NOACCESS (pattern, sizeof (cairo_surface_pattern_t));
+	break;
+    case CAIRO_PATTERN_TYPE_LINEAR:
+	VALGRIND_MAKE_MEM_NOACCESS (pattern, sizeof (cairo_linear_pattern_t));
+	break;
+    case CAIRO_PATTERN_TYPE_RADIAL:
+	VALGRIND_MAKE_MEM_NOACCESS (pattern, sizeof (cairo_radial_pattern_t));
+	break;
+    case CAIRO_PATTERN_TYPE_MESH:
+	VALGRIND_MAKE_MEM_NOACCESS (pattern, sizeof (cairo_mesh_pattern_t));
+	break;
+    case CAIRO_PATTERN_TYPE_RASTER_SOURCE:
+	break;
+    }
+#endif
+}
+
+cairo_status_t
+_cairo_pattern_create_copy (cairo_pattern_t	  **pattern_out,
+			    const cairo_pattern_t  *other)
+{
+    cairo_pattern_t *pattern;
+    cairo_status_t status;
+
+    if (other->status)
+	return other->status;
+
+    switch (other->type) {
+    case CAIRO_PATTERN_TYPE_SOLID:
+	pattern = malloc (sizeof (cairo_solid_pattern_t));
+	break;
+    case CAIRO_PATTERN_TYPE_SURFACE:
+	pattern = malloc (sizeof (cairo_surface_pattern_t));
+	break;
+    case CAIRO_PATTERN_TYPE_LINEAR:
+	pattern = malloc (sizeof (cairo_linear_pattern_t));
+	break;
+    case CAIRO_PATTERN_TYPE_RADIAL:
+	pattern = malloc (sizeof (cairo_radial_pattern_t));
+	break;
+    case CAIRO_PATTERN_TYPE_MESH:
+	pattern = malloc (sizeof (cairo_mesh_pattern_t));
+	break;
+    case CAIRO_PATTERN_TYPE_RASTER_SOURCE:
+	pattern = malloc (sizeof (cairo_raster_source_pattern_t));
+	break;
+    default:
+	ASSERT_NOT_REACHED;
+	return _cairo_error (CAIRO_STATUS_PATTERN_TYPE_MISMATCH);
+    }
+    if (unlikely (pattern == NULL))
+	return _cairo_error (CAIRO_STATUS_NO_MEMORY);
+
+    status = _cairo_pattern_init_copy (pattern, other);
+    if (unlikely (status)) {
+	free (pattern);
+	return status;
+    }
+
+    CAIRO_REFERENCE_COUNT_INIT (&pattern->ref_count, 1);
+    *pattern_out = pattern;
+    return CAIRO_STATUS_SUCCESS;
+}
+
+void
+_cairo_pattern_init_solid (cairo_solid_pattern_t *pattern,
+			   const cairo_color_t	 *color)
+{
+    _cairo_pattern_init (&pattern->base, CAIRO_PATTERN_TYPE_SOLID);
+    pattern->color = *color;
+}
+
+void
+_cairo_pattern_init_for_surface (cairo_surface_pattern_t *pattern,
+				 cairo_surface_t	 *surface)
+{
+    if (surface->status) {
+	/* Force to solid to simplify the pattern_fini process. */
+	_cairo_pattern_init (&pattern->base, CAIRO_PATTERN_TYPE_SOLID);
+	_cairo_pattern_set_error (&pattern->base, surface->status);
+	return;
+    }
+
+    _cairo_pattern_init (&pattern->base, CAIRO_PATTERN_TYPE_SURFACE);
+
+    pattern->surface = cairo_surface_reference (surface);
+}
+
+static void
+_cairo_pattern_init_gradient (cairo_gradient_pattern_t *pattern,
+			      cairo_pattern_type_t     type)
+{
+    _cairo_pattern_init (&pattern->base, type);
+
+    pattern->n_stops    = 0;
+    pattern->stops_size = 0;
+    pattern->stops      = NULL;
+}
+
+static void
+_cairo_pattern_init_linear (cairo_linear_pattern_t *pattern,
+			    double x0, double y0, double x1, double y1)
+{
+    _cairo_pattern_init_gradient (&pattern->base, CAIRO_PATTERN_TYPE_LINEAR);
+
+    pattern->pd1.x = x0;
+    pattern->pd1.y = y0;
+    pattern->pd2.x = x1;
+    pattern->pd2.y = y1;
+}
+
+static void
+_cairo_pattern_init_radial (cairo_radial_pattern_t *pattern,
+			    double cx0, double cy0, double radius0,
+			    double cx1, double cy1, double radius1)
+{
+    _cairo_pattern_init_gradient (&pattern->base, CAIRO_PATTERN_TYPE_RADIAL);
+
+    pattern->cd1.center.x = cx0;
+    pattern->cd1.center.y = cy0;
+    pattern->cd1.radius   = fabs (radius0);
+    pattern->cd2.center.x = cx1;
+    pattern->cd2.center.y = cy1;
+    pattern->cd2.radius   = fabs (radius1);
+}
+
+cairo_pattern_t *
+_cairo_pattern_create_solid (const cairo_color_t *color)
+{
+    cairo_solid_pattern_t *pattern;
+
+    pattern =
+	_freed_pool_get (&freed_pattern_pool[CAIRO_PATTERN_TYPE_SOLID]);
+    if (unlikely (pattern == NULL)) {
+	/* None cached, need to create a new pattern. */
+	pattern = malloc (sizeof (cairo_solid_pattern_t));
+	if (unlikely (pattern == NULL)) {
+	    _cairo_error_throw (CAIRO_STATUS_NO_MEMORY);
+	    return (cairo_pattern_t *) &_cairo_pattern_nil;
+	}
+    }
+
+    _cairo_pattern_init_solid (pattern, color);
+    CAIRO_REFERENCE_COUNT_INIT (&pattern->base.ref_count, 1);
+
+    return &pattern->base;
+}
+
+cairo_pattern_t *
+_cairo_pattern_create_in_error (cairo_status_t status)
+{
+    cairo_pattern_t *pattern;
+
+    if (status == CAIRO_STATUS_NO_MEMORY)
+	return (cairo_pattern_t *)&_cairo_pattern_nil.base;
+
+    CAIRO_MUTEX_INITIALIZE ();
+
+    pattern = _cairo_pattern_create_solid (CAIRO_COLOR_BLACK);
+    if (pattern->status == CAIRO_STATUS_SUCCESS)
+	status = _cairo_pattern_set_error (pattern, status);
+
+    return pattern;
+}
+
+/**
+ * cairo_pattern_create_rgb:
+ * @red: red component of the color
+ * @green: green component of the color
+ * @blue: blue component of the color
+ *
+ * Creates a new #cairo_pattern_t corresponding to an opaque color.  The
+ * color components are floating point numbers in the range 0 to 1.
+ * If the values passed in are outside that range, they will be
+ * clamped.
+ *
+ * Return value: the newly created #cairo_pattern_t if successful, or
+ * an error pattern in case of no memory.  The caller owns the
+ * returned object and should call cairo_pattern_destroy() when
+ * finished with it.
+ *
+ * This function will always return a valid pointer, but if an error
+ * occurred the pattern status will be set to an error.  To inspect
+ * the status of a pattern use cairo_pattern_status().
+ *
+ * Since: 1.0
+ **/
+cairo_pattern_t *
+cairo_pattern_create_rgb (double red, double green, double blue)
+{
+    return cairo_pattern_create_rgba (red, green, blue, 1.0);
+}
+slim_hidden_def (cairo_pattern_create_rgb);
+
+/**
+ * cairo_pattern_create_rgba:
+ * @red: red component of the color
+ * @green: green component of the color
+ * @blue: blue component of the color
+ * @alpha: alpha component of the color
+ *
+ * Creates a new #cairo_pattern_t corresponding to a translucent color.
+ * The color components are floating point numbers in the range 0 to
+ * 1.  If the values passed in are outside that range, they will be
+ * clamped.
+ *
+ * Return value: the newly created #cairo_pattern_t if successful, or
+ * an error pattern in case of no memory.  The caller owns the
+ * returned object and should call cairo_pattern_destroy() when
+ * finished with it.
+ *
+ * This function will always return a valid pointer, but if an error
+ * occurred the pattern status will be set to an error.  To inspect
+ * the status of a pattern use cairo_pattern_status().
+ *
+ * Since: 1.0
+ **/
+cairo_pattern_t *
+cairo_pattern_create_rgba (double red, double green, double blue,
+			   double alpha)
+{
+    cairo_color_t color;
+
+    red   = _cairo_restrict_value (red,   0.0, 1.0);
+    green = _cairo_restrict_value (green, 0.0, 1.0);
+    blue  = _cairo_restrict_value (blue,  0.0, 1.0);
+    alpha = _cairo_restrict_value (alpha, 0.0, 1.0);
+
+    _cairo_color_init_rgba (&color, red, green, blue, alpha);
+
+    CAIRO_MUTEX_INITIALIZE ();
+
+    return _cairo_pattern_create_solid (&color);
+}
+slim_hidden_def (cairo_pattern_create_rgba);
+
+/**
+ * cairo_pattern_create_for_surface:
+ * @surface: the surface
+ *
+ * Create a new #cairo_pattern_t for the given surface.
+ *
+ * Return value: the newly created #cairo_pattern_t if successful, or
+ * an error pattern in case of no memory.  The caller owns the
+ * returned object and should call cairo_pattern_destroy() when
+ * finished with it.
+ *
+ * This function will always return a valid pointer, but if an error
+ * occurred the pattern status will be set to an error.  To inspect
+ * the status of a pattern use cairo_pattern_status().
+ *
+ * Since: 1.0
+ **/
+cairo_pattern_t *
+cairo_pattern_create_for_surface (cairo_surface_t *surface)
+{
+    cairo_surface_pattern_t *pattern;
+
+    if (surface == NULL) {
+	_cairo_error_throw (CAIRO_STATUS_NULL_POINTER);
+	return (cairo_pattern_t*) &_cairo_pattern_nil_null_pointer;
+    }
+
+    if (surface->status)
+	return _cairo_pattern_create_in_error (surface->status);
+
+    pattern =
+	_freed_pool_get (&freed_pattern_pool[CAIRO_PATTERN_TYPE_SURFACE]);
+    if (unlikely (pattern == NULL)) {
+	pattern = malloc (sizeof (cairo_surface_pattern_t));
+	if (unlikely (pattern == NULL)) {
+	    _cairo_error_throw (CAIRO_STATUS_NO_MEMORY);
+	    return (cairo_pattern_t *)&_cairo_pattern_nil.base;
+	}
+    }
+
+    CAIRO_MUTEX_INITIALIZE ();
+
+    _cairo_pattern_init_for_surface (pattern, surface);
+    CAIRO_REFERENCE_COUNT_INIT (&pattern->base.ref_count, 1);
+
+    return &pattern->base;
+}
+slim_hidden_def (cairo_pattern_create_for_surface);
+
+/**
+ * cairo_pattern_create_linear:
+ * @x0: x coordinate of the start point
+ * @y0: y coordinate of the start point
+ * @x1: x coordinate of the end point
+ * @y1: y coordinate of the end point
+ *
+ * Create a new linear gradient #cairo_pattern_t along the line defined
+ * by (x0, y0) and (x1, y1).  Before using the gradient pattern, a
+ * number of color stops should be defined using
+ * cairo_pattern_add_color_stop_rgb() or
+ * cairo_pattern_add_color_stop_rgba().
+ *
+ * Note: The coordinates here are in pattern space. For a new pattern,
+ * pattern space is identical to user space, but the relationship
+ * between the spaces can be changed with cairo_pattern_set_matrix().
+ *
+ * Return value: the newly created #cairo_pattern_t if successful, or
+ * an error pattern in case of no memory.  The caller owns the
+ * returned object and should call cairo_pattern_destroy() when
+ * finished with it.
+ *
+ * This function will always return a valid pointer, but if an error
+ * occurred the pattern status will be set to an error.  To inspect
+ * the status of a pattern use cairo_pattern_status().
+ *
+ * Since: 1.0
+ **/
+cairo_pattern_t *
+cairo_pattern_create_linear (double x0, double y0, double x1, double y1)
+{
+    cairo_linear_pattern_t *pattern;
+
+    pattern =
+	_freed_pool_get (&freed_pattern_pool[CAIRO_PATTERN_TYPE_LINEAR]);
+    if (unlikely (pattern == NULL)) {
+	pattern = malloc (sizeof (cairo_linear_pattern_t));
+	if (unlikely (pattern == NULL)) {
+	    _cairo_error_throw (CAIRO_STATUS_NO_MEMORY);
+	    return (cairo_pattern_t *) &_cairo_pattern_nil.base;
+	}
+    }
+
+    CAIRO_MUTEX_INITIALIZE ();
+
+    _cairo_pattern_init_linear (pattern, x0, y0, x1, y1);
+    CAIRO_REFERENCE_COUNT_INIT (&pattern->base.base.ref_count, 1);
+
+    return &pattern->base.base;
+}
+
+/**
+ * cairo_pattern_create_radial:
+ * @cx0: x coordinate for the center of the start circle
+ * @cy0: y coordinate for the center of the start circle
+ * @radius0: radius of the start circle
+ * @cx1: x coordinate for the center of the end circle
+ * @cy1: y coordinate for the center of the end circle
+ * @radius1: radius of the end circle
+ *
+ * Creates a new radial gradient #cairo_pattern_t between the two
+ * circles defined by (cx0, cy0, radius0) and (cx1, cy1, radius1).  Before using the
+ * gradient pattern, a number of color stops should be defined using
+ * cairo_pattern_add_color_stop_rgb() or
+ * cairo_pattern_add_color_stop_rgba().
+ *
+ * Note: The coordinates here are in pattern space. For a new pattern,
+ * pattern space is identical to user space, but the relationship
+ * between the spaces can be changed with cairo_pattern_set_matrix().
+ *
+ * Return value: the newly created #cairo_pattern_t if successful, or
+ * an error pattern in case of no memory.  The caller owns the
+ * returned object and should call cairo_pattern_destroy() when
+ * finished with it.
+ *
+ * This function will always return a valid pointer, but if an error
+ * occurred the pattern status will be set to an error.  To inspect
+ * the status of a pattern use cairo_pattern_status().
+ *
+ * Since: 1.0
+ **/
+cairo_pattern_t *
+cairo_pattern_create_radial (double cx0, double cy0, double radius0,
+			     double cx1, double cy1, double radius1)
+{
+    cairo_radial_pattern_t *pattern;
+
+    pattern =
+	_freed_pool_get (&freed_pattern_pool[CAIRO_PATTERN_TYPE_RADIAL]);
+    if (unlikely (pattern == NULL)) {
+	pattern = malloc (sizeof (cairo_radial_pattern_t));
+	if (unlikely (pattern == NULL)) {
+	    _cairo_error_throw (CAIRO_STATUS_NO_MEMORY);
+	    return (cairo_pattern_t *) &_cairo_pattern_nil.base;
+	}
+    }
+
+    CAIRO_MUTEX_INITIALIZE ();
+
+    _cairo_pattern_init_radial (pattern, cx0, cy0, radius0, cx1, cy1, radius1);
+    CAIRO_REFERENCE_COUNT_INIT (&pattern->base.base.ref_count, 1);
+
+    return &pattern->base.base;
+}
+
+/* This order is specified in the diagram in the documentation for
+ * cairo_pattern_create_mesh() */
+static const int mesh_path_point_i[12] = { 0, 0, 0, 0, 1, 2, 3, 3, 3, 3, 2, 1 };
+static const int mesh_path_point_j[12] = { 0, 1, 2, 3, 3, 3, 3, 2, 1, 0, 0, 0 };
+static const int mesh_control_point_i[4] = { 1, 1, 2, 2 };
+static const int mesh_control_point_j[4] = { 1, 2, 2, 1 };
+
+/**
+ * cairo_pattern_create_mesh:
+ *
+ * Create a new mesh pattern.
+ *
+ * Mesh patterns are tensor-product patch meshes (type 7 shadings in
+ * PDF). Mesh patterns may also be used to create other types of
+ * shadings that are special cases of tensor-product patch meshes such
+ * as Coons patch meshes (type 6 shading in PDF) and Gouraud-shaded
+ * triangle meshes (type 4 and 5 shadings in PDF).
+ *
+ * Mesh patterns consist of one or more tensor-product patches, which
+ * should be defined before using the mesh pattern. Using a mesh
+ * pattern with a partially defined patch as source or mask will put
+ * the context in an error status with a status of
+ * %CAIRO_STATUS_INVALID_MESH_CONSTRUCTION.
+ *
+ * A tensor-product patch is defined by 4 Bézier curves (side 0, 1, 2,
+ * 3) and by 4 additional control points (P0, P1, P2, P3) that provide
+ * further control over the patch and complete the definition of the
+ * tensor-product patch. The corner C0 is the first point of the
+ * patch.
+ *
+ * Degenerate sides are permitted so straight lines may be used. A
+ * zero length line on one side may be used to create 3 sided patches.
+ *
+ * <informalexample><screen>
+ *       C1     Side 1       C2
+ *        +---------------+
+ *        |               |
+ *        |  P1       P2  |
+ *        |               |
+ * Side 0 |               | Side 2
+ *        |               |
+ *        |               |
+ *        |  P0       P3  |
+ *        |               |
+ *        +---------------+
+ *      C0     Side 3        C3
+ * </screen></informalexample>
+ *
+ * Each patch is constructed by first calling
+ * cairo_mesh_pattern_begin_patch(), then cairo_mesh_pattern_move_to()
+ * to specify the first point in the patch (C0). Then the sides are
+ * specified with calls to cairo_mesh_pattern_curve_to() and
+ * cairo_mesh_pattern_line_to().
+ *
+ * The four additional control points (P0, P1, P2, P3) in a patch can
+ * be specified with cairo_mesh_pattern_set_control_point().
+ *
+ * At each corner of the patch (C0, C1, C2, C3) a color may be
+ * specified with cairo_mesh_pattern_set_corner_color_rgb() or
+ * cairo_mesh_pattern_set_corner_color_rgba(). Any corner whose color
+ * is not explicitly specified defaults to transparent black.
+ *
+ * A Coons patch is a special case of the tensor-product patch where
+ * the control points are implicitly defined by the sides of the
+ * patch. The default value for any control point not specified is the
+ * implicit value for a Coons patch, i.e. if no control points are
+ * specified the patch is a Coons patch.
+ *
+ * A triangle is a special case of the tensor-product patch where the
+ * control points are implicitly defined by the sides of the patch,
+ * all the sides are lines and one of them has length 0, i.e. if the
+ * patch is specified using just 3 lines, it is a triangle. If the
+ * corners connected by the 0-length side have the same color, the
+ * patch is a Gouraud-shaded triangle.
+ *
+ * Patches may be oriented differently to the above diagram. For
+ * example the first point could be at the top left. The diagram only
+ * shows the relationship between the sides, corners and control
+ * points. Regardless of where the first point is located, when
+ * specifying colors, corner 0 will always be the first point, corner
+ * 1 the point between side 0 and side 1 etc.
+ *
+ * Calling cairo_mesh_pattern_end_patch() completes the current
+ * patch. If less than 4 sides have been defined, the first missing
+ * side is defined as a line from the current point to the first point
+ * of the patch (C0) and the other sides are degenerate lines from C0
+ * to C0. The corners between the added sides will all be coincident
+ * with C0 of the patch and their color will be set to be the same as
+ * the color of C0.
+ *
+ * Additional patches may be added with additional calls to
+ * cairo_mesh_pattern_begin_patch()/cairo_mesh_pattern_end_patch().
+ *
+ * <informalexample><programlisting>
+ * cairo_pattern_t *pattern = cairo_pattern_create_mesh ();
+ *
+ * /&ast; Add a Coons patch &ast;/
+ * cairo_mesh_pattern_begin_patch (pattern);
+ * cairo_mesh_pattern_move_to (pattern, 0, 0);
+ * cairo_mesh_pattern_curve_to (pattern, 30, -30,  60,  30, 100, 0);
+ * cairo_mesh_pattern_curve_to (pattern, 60,  30, 130,  60, 100, 100);
+ * cairo_mesh_pattern_curve_to (pattern, 60,  70,  30, 130,   0, 100);
+ * cairo_mesh_pattern_curve_to (pattern, 30,  70, -30,  30,   0, 0);
+ * cairo_mesh_pattern_set_corner_color_rgb (pattern, 0, 1, 0, 0);
+ * cairo_mesh_pattern_set_corner_color_rgb (pattern, 1, 0, 1, 0);
+ * cairo_mesh_pattern_set_corner_color_rgb (pattern, 2, 0, 0, 1);
+ * cairo_mesh_pattern_set_corner_color_rgb (pattern, 3, 1, 1, 0);
+ * cairo_mesh_pattern_end_patch (pattern);
+ *
+ * /&ast; Add a Gouraud-shaded triangle &ast;/
+ * cairo_mesh_pattern_begin_patch (pattern)
+ * cairo_mesh_pattern_move_to (pattern, 100, 100);
+ * cairo_mesh_pattern_line_to (pattern, 130, 130);
+ * cairo_mesh_pattern_line_to (pattern, 130,  70);
+ * cairo_mesh_pattern_set_corner_color_rgb (pattern, 0, 1, 0, 0);
+ * cairo_mesh_pattern_set_corner_color_rgb (pattern, 1, 0, 1, 0);
+ * cairo_mesh_pattern_set_corner_color_rgb (pattern, 2, 0, 0, 1);
+ * cairo_mesh_pattern_end_patch (pattern)
+ * </programlisting></informalexample>
+ *
+ * When two patches overlap, the last one that has been added is drawn
+ * over the first one.
+ *
+ * When a patch folds over itself, points are sorted depending on
+ * their parameter coordinates inside the patch. The v coordinate
+ * ranges from 0 to 1 when moving from side 3 to side 1; the u
+ * coordinate ranges from 0 to 1 when going from side 0 to side
+ * 2. Points with higher v coordinate hide points with lower v
+ * coordinate. When two points have the same v coordinate, the one
+ * with higher u coordinate is above. This means that points nearer to
+ * side 1 are above points nearer to side 3; when this is not
+ * sufficient to decide which point is above (for example when both
+ * points belong to side 1 or side 3) points nearer to side 2 are
+ * above points nearer to side 0.
+ *
+ * For a complete definition of tensor-product patches, see the PDF
+ * specification (ISO32000), which describes the parametrization in
+ * detail.
+ *
+ * Note: The coordinates are always in pattern space. For a new
+ * pattern, pattern space is identical to user space, but the
+ * relationship between the spaces can be changed with
+ * cairo_pattern_set_matrix().
+ *
+ * Return value: the newly created #cairo_pattern_t if successful, or
+ * an error pattern in case of no memory. The caller owns the returned
+ * object and should call cairo_pattern_destroy() when finished with
+ * it.
+ *
+ * This function will always return a valid pointer, but if an error
+ * occurred the pattern status will be set to an error. To inspect the
+ * status of a pattern use cairo_pattern_status().
+ *
+ * Since: 1.12
+ **/
+cairo_pattern_t *
+cairo_pattern_create_mesh (void)
+{
+    cairo_mesh_pattern_t *pattern;
+
+    pattern =
+	_freed_pool_get (&freed_pattern_pool[CAIRO_PATTERN_TYPE_MESH]);
+    if (unlikely (pattern == NULL)) {
+	pattern = malloc (sizeof (cairo_mesh_pattern_t));
+	if (unlikely (pattern == NULL)) {
+	    _cairo_error_throw (CAIRO_STATUS_NO_MEMORY);
+	    return (cairo_pattern_t *) &_cairo_pattern_nil.base;
+	}
+    }
+
+    CAIRO_MUTEX_INITIALIZE ();
+
+    _cairo_pattern_init (&pattern->base, CAIRO_PATTERN_TYPE_MESH);
+    _cairo_array_init (&pattern->patches, sizeof (cairo_mesh_patch_t));
+    pattern->current_patch = NULL;
+    CAIRO_REFERENCE_COUNT_INIT (&pattern->base.ref_count, 1);
+
+    return &pattern->base;
+}
+
+/**
+ * cairo_pattern_reference:
+ * @pattern: a #cairo_pattern_t
+ *
+ * Increases the reference count on @pattern by one. This prevents
+ * @pattern from being destroyed until a matching call to
+ * cairo_pattern_destroy() is made.
+ *
+ * The number of references to a #cairo_pattern_t can be get using
+ * cairo_pattern_get_reference_count().
+ *
+ * Return value: the referenced #cairo_pattern_t.
+ *
+ * Since: 1.0
+ **/
+cairo_pattern_t *
+cairo_pattern_reference (cairo_pattern_t *pattern)
+{
+    if (pattern == NULL ||
+	    CAIRO_REFERENCE_COUNT_IS_INVALID (&pattern->ref_count))
+	return pattern;
+
+    assert (CAIRO_REFERENCE_COUNT_HAS_REFERENCE (&pattern->ref_count));
+
+    _cairo_reference_count_inc (&pattern->ref_count);
+
+    return pattern;
+}
+slim_hidden_def (cairo_pattern_reference);
+
+/**
+ * cairo_pattern_get_type:
+ * @pattern: a #cairo_pattern_t
+ *
+ * This function returns the type a pattern.
+ * See #cairo_pattern_type_t for available types.
+ *
+ * Return value: The type of @pattern.
+ *
+ * Since: 1.2
+ **/
+cairo_pattern_type_t
+cairo_pattern_get_type (cairo_pattern_t *pattern)
+{
+    return pattern->type;
+}
+
+/**
+ * cairo_pattern_status:
+ * @pattern: a #cairo_pattern_t
+ *
+ * Checks whether an error has previously occurred for this
+ * pattern.
+ *
+ * Return value: %CAIRO_STATUS_SUCCESS, %CAIRO_STATUS_NO_MEMORY,
+ * %CAIRO_STATUS_INVALID_MATRIX, %CAIRO_STATUS_PATTERN_TYPE_MISMATCH,
+ * or %CAIRO_STATUS_INVALID_MESH_CONSTRUCTION.
+ *
+ * Since: 1.0
+ **/
+cairo_status_t
+cairo_pattern_status (cairo_pattern_t *pattern)
+{
+    return pattern->status;
+}
+
+/**
+ * cairo_pattern_destroy:
+ * @pattern: a #cairo_pattern_t
+ *
+ * Decreases the reference count on @pattern by one. If the result is
+ * zero, then @pattern and all associated resources are freed.  See
+ * cairo_pattern_reference().
+ *
+ * Since: 1.0
+ **/
+void
+cairo_pattern_destroy (cairo_pattern_t *pattern)
+{
+    cairo_pattern_type_t type;
+
+    if (pattern == NULL ||
+	    CAIRO_REFERENCE_COUNT_IS_INVALID (&pattern->ref_count))
+	return;
+
+    assert (CAIRO_REFERENCE_COUNT_HAS_REFERENCE (&pattern->ref_count));
+
+    if (! _cairo_reference_count_dec_and_test (&pattern->ref_count))
+	return;
+
+    type = pattern->type;
+    _cairo_pattern_fini (pattern);
+
+    /* maintain a small cache of freed patterns */
+    if (type < ARRAY_LENGTH (freed_pattern_pool))
+	_freed_pool_put (&freed_pattern_pool[type], pattern);
+    else
+	free (pattern);
+}
+slim_hidden_def (cairo_pattern_destroy);
+
+/**
+ * cairo_pattern_get_reference_count:
+ * @pattern: a #cairo_pattern_t
+ *
+ * Returns the current reference count of @pattern.
+ *
+ * Return value: the current reference count of @pattern.  If the
+ * object is a nil object, 0 will be returned.
+ *
+ * Since: 1.4
+ **/
+unsigned int
+cairo_pattern_get_reference_count (cairo_pattern_t *pattern)
+{
+    if (pattern == NULL ||
+	    CAIRO_REFERENCE_COUNT_IS_INVALID (&pattern->ref_count))
+	return 0;
+
+    return CAIRO_REFERENCE_COUNT_GET_VALUE (&pattern->ref_count);
+}
+
+/**
+ * cairo_pattern_get_user_data:
+ * @pattern: a #cairo_pattern_t
+ * @key: the address of the #cairo_user_data_key_t the user data was
+ * attached to
+ *
+ * Return user data previously attached to @pattern using the
+ * specified key.  If no user data has been attached with the given
+ * key this function returns %NULL.
+ *
+ * Return value: the user data previously attached or %NULL.
+ *
+ * Since: 1.4
+ **/
+void *
+cairo_pattern_get_user_data (cairo_pattern_t		 *pattern,
+			     const cairo_user_data_key_t *key)
+{
+    return _cairo_user_data_array_get_data (&pattern->user_data,
+					    key);
+}
+
+/**
+ * cairo_pattern_set_user_data:
+ * @pattern: a #cairo_pattern_t
+ * @key: the address of a #cairo_user_data_key_t to attach the user data to
+ * @user_data: the user data to attach to the #cairo_pattern_t
+ * @destroy: a #cairo_destroy_func_t which will be called when the
+ * #cairo_t is destroyed or when new user data is attached using the
+ * same key.
+ *
+ * Attach user data to @pattern.  To remove user data from a surface,
+ * call this function with the key that was used to set it and %NULL
+ * for @data.
+ *
+ * Return value: %CAIRO_STATUS_SUCCESS or %CAIRO_STATUS_NO_MEMORY if a
+ * slot could not be allocated for the user data.
+ *
+ * Since: 1.4
+ **/
+cairo_status_t
+cairo_pattern_set_user_data (cairo_pattern_t		 *pattern,
+			     const cairo_user_data_key_t *key,
+			     void			 *user_data,
+			     cairo_destroy_func_t	  destroy)
+{
+    if (CAIRO_REFERENCE_COUNT_IS_INVALID (&pattern->ref_count))
+	return pattern->status;
+
+    return _cairo_user_data_array_set_data (&pattern->user_data,
+					    key, user_data, destroy);
+}
+
+/**
+ * cairo_mesh_pattern_begin_patch:
+ * @pattern: a #cairo_pattern_t
+ *
+ * Begin a patch in a mesh pattern.
+ *
+ * After calling this function, the patch shape should be defined with
+ * cairo_mesh_pattern_move_to(), cairo_mesh_pattern_line_to() and
+ * cairo_mesh_pattern_curve_to().
+ *
+ * After defining the patch, cairo_mesh_pattern_end_patch() must be
+ * called before using @pattern as a source or mask.
+ *
+ * Note: If @pattern is not a mesh pattern then @pattern will be put
+ * into an error status with a status of
+ * %CAIRO_STATUS_PATTERN_TYPE_MISMATCH. If @pattern already has a
+ * current patch, it will be put into an error status with a status of
+ * %CAIRO_STATUS_INVALID_MESH_CONSTRUCTION.
+ *
+ * Since: 1.12
+ **/
+void
+cairo_mesh_pattern_begin_patch (cairo_pattern_t *pattern)
+{
+    cairo_mesh_pattern_t *mesh;
+    cairo_status_t status;
+    cairo_mesh_patch_t *current_patch;
+    int i;
+
+    if (unlikely (pattern->status))
+	return;
+
+    if (unlikely (pattern->type != CAIRO_PATTERN_TYPE_MESH)) {
+	_cairo_pattern_set_error (pattern, CAIRO_STATUS_PATTERN_TYPE_MISMATCH);
+	return;
+    }
+
+    mesh = (cairo_mesh_pattern_t *) pattern;
+    if (unlikely (mesh->current_patch)) {
+	_cairo_pattern_set_error (pattern, CAIRO_STATUS_INVALID_MESH_CONSTRUCTION);
+	return;
+    }
+
+    status = _cairo_array_allocate (&mesh->patches, 1, (void **) &current_patch);
+    if (unlikely (status)) {
+	_cairo_pattern_set_error (pattern, status);
+	return;
+    }
+
+    mesh->current_patch = current_patch;
+    mesh->current_side = -2; /* no current point */
+
+    for (i = 0; i < 4; i++)
+	mesh->has_control_point[i] = FALSE;
+
+    for (i = 0; i < 4; i++)
+	mesh->has_color[i] = FALSE;
+}
+
+
+static void
+_calc_control_point (cairo_mesh_patch_t *patch, int control_point)
+{
+    /* The Coons patch is a special case of the Tensor Product patch
+     * where the four control points are:
+     *
+     * P11 = S(1/3, 1/3)
+     * P12 = S(1/3, 2/3)
+     * P21 = S(2/3, 1/3)
+     * P22 = S(2/3, 2/3)
+     *
+     * where S is the gradient surface.
+     *
+     * When one or more control points has not been specified
+     * calculated the Coons patch control points are substituted. If
+     * no control points are specified the gradient will be a Coons
+     * patch.
+     *
+     * The equations below are defined in the ISO32000 standard.
+     */
+    cairo_point_double_t *p[3][3];
+    int cp_i, cp_j, i, j;
+
+    cp_i = mesh_control_point_i[control_point];
+    cp_j = mesh_control_point_j[control_point];
+
+    for (i = 0; i < 3; i++)
+	for (j = 0; j < 3; j++)
+	    p[i][j] = &patch->points[cp_i ^ i][cp_j ^ j];
+
+    p[0][0]->x = (- 4 * p[1][1]->x
+		  + 6 * (p[1][0]->x + p[0][1]->x)
+		  - 2 * (p[1][2]->x + p[2][1]->x)
+		  + 3 * (p[2][0]->x + p[0][2]->x)
+		  - 1 * p[2][2]->x) * (1. / 9);
+
+    p[0][0]->y = (- 4 * p[1][1]->y
+		  + 6 * (p[1][0]->y + p[0][1]->y)
+		  - 2 * (p[1][2]->y + p[2][1]->y)
+		  + 3 * (p[2][0]->y + p[0][2]->y)
+		  - 1 * p[2][2]->y) * (1. / 9);
+}
+
+/**
+ * cairo_mesh_pattern_end_patch:
+ * @pattern: a #cairo_pattern_t
+ *
+ * Indicates the end of the current patch in a mesh pattern.
+ *
+ * If the current patch has less than 4 sides, it is closed with a
+ * straight line from the current point to the first point of the
+ * patch as if cairo_mesh_pattern_line_to() was used.
+ *
+ * Note: If @pattern is not a mesh pattern then @pattern will be put
+ * into an error status with a status of
+ * %CAIRO_STATUS_PATTERN_TYPE_MISMATCH. If @pattern has no current
+ * patch or the current patch has no current point, @pattern will be
+ * put into an error status with a status of
+ * %CAIRO_STATUS_INVALID_MESH_CONSTRUCTION.
+ *
+ * Since: 1.12
+ **/
+void
+cairo_mesh_pattern_end_patch (cairo_pattern_t *pattern)
+{
+    cairo_mesh_pattern_t *mesh;
+    cairo_mesh_patch_t *current_patch;
+    int i;
+
+    if (unlikely (pattern->status))
+	return;
+
+    if (unlikely (pattern->type != CAIRO_PATTERN_TYPE_MESH)) {
+	_cairo_pattern_set_error (pattern, CAIRO_STATUS_PATTERN_TYPE_MISMATCH);
+	return;
+    }
+
+    mesh = (cairo_mesh_pattern_t *) pattern;
+    current_patch = mesh->current_patch;
+    if (unlikely (!current_patch)) {
+	_cairo_pattern_set_error (pattern, CAIRO_STATUS_INVALID_MESH_CONSTRUCTION);
+	return;
+    }
+
+    if (unlikely (mesh->current_side == -2)) {
+	_cairo_pattern_set_error (pattern, CAIRO_STATUS_INVALID_MESH_CONSTRUCTION);
+	return;
+    }
+
+    while (mesh->current_side < 3) {
+	int corner_num;
+
+	cairo_mesh_pattern_line_to (pattern,
+				    current_patch->points[0][0].x,
+				    current_patch->points[0][0].y);
+
+	corner_num = mesh->current_side + 1;
+	if (corner_num < 4 && ! mesh->has_color[corner_num]) {
+	    current_patch->colors[corner_num] = current_patch->colors[0];
+	    mesh->has_color[corner_num] = TRUE;
+	}
+    }
+
+    for (i = 0; i < 4; i++) {
+	if (! mesh->has_control_point[i])
+	    _calc_control_point (current_patch, i);
+    }
+
+    for (i = 0; i < 4; i++) {
+	if (! mesh->has_color[i])
+	    current_patch->colors[i] = *CAIRO_COLOR_TRANSPARENT;
+    }
+
+    mesh->current_patch = NULL;
+}
+
+/**
+ * cairo_mesh_pattern_curve_to:
+ * @pattern: a #cairo_pattern_t
+ * @x1: the X coordinate of the first control point
+ * @y1: the Y coordinate of the first control point
+ * @x2: the X coordinate of the second control point
+ * @y2: the Y coordinate of the second control point
+ * @x3: the X coordinate of the end of the curve
+ * @y3: the Y coordinate of the end of the curve
+ *
+ * Adds a cubic Bézier spline to the current patch from the current
+ * point to position (@x3, @y3) in pattern-space coordinates, using
+ * (@x1, @y1) and (@x2, @y2) as the control points.
+ *
+ * If the current patch has no current point before the call to
+ * cairo_mesh_pattern_curve_to(), this function will behave as if
+ * preceded by a call to cairo_mesh_pattern_move_to(@pattern, @x1,
+ * @y1).
+ *
+ * After this call the current point will be (@x3, @y3).
+ *
+ * Note: If @pattern is not a mesh pattern then @pattern will be put
+ * into an error status with a status of
+ * %CAIRO_STATUS_PATTERN_TYPE_MISMATCH. If @pattern has no current
+ * patch or the current patch already has 4 sides, @pattern will be
+ * put into an error status with a status of
+ * %CAIRO_STATUS_INVALID_MESH_CONSTRUCTION.
+ *
+ * Since: 1.12
+ **/
+void
+cairo_mesh_pattern_curve_to (cairo_pattern_t *pattern,
+			     double x1, double y1,
+			     double x2, double y2,
+			     double x3, double y3)
+{
+    cairo_mesh_pattern_t *mesh;
+    int current_point, i, j;
+
+    if (unlikely (pattern->status))
+	return;
+
+    if (unlikely (pattern->type != CAIRO_PATTERN_TYPE_MESH)) {
+	_cairo_pattern_set_error (pattern, CAIRO_STATUS_PATTERN_TYPE_MISMATCH);
+	return;
+    }
+
+    mesh = (cairo_mesh_pattern_t *) pattern;
+    if (unlikely (!mesh->current_patch)) {
+	_cairo_pattern_set_error (pattern, CAIRO_STATUS_INVALID_MESH_CONSTRUCTION);
+	return;
+    }
+
+    if (unlikely (mesh->current_side == 3)) {
+	_cairo_pattern_set_error (pattern, CAIRO_STATUS_INVALID_MESH_CONSTRUCTION);
+	return;
+    }
+
+    if (mesh->current_side == -2)
+	cairo_mesh_pattern_move_to (pattern, x1, y1);
+
+    assert (mesh->current_side >= -1);
+    assert (pattern->status == CAIRO_STATUS_SUCCESS);
+
+    mesh->current_side++;
+
+    current_point = 3 * mesh->current_side;
+
+    current_point++;
+    i = mesh_path_point_i[current_point];
+    j = mesh_path_point_j[current_point];
+    mesh->current_patch->points[i][j].x = x1;
+    mesh->current_patch->points[i][j].y = y1;
+
+    current_point++;
+    i = mesh_path_point_i[current_point];
+    j = mesh_path_point_j[current_point];
+    mesh->current_patch->points[i][j].x = x2;
+    mesh->current_patch->points[i][j].y = y2;
+
+    current_point++;
+    if (current_point < 12) {
+	i = mesh_path_point_i[current_point];
+	j = mesh_path_point_j[current_point];
+	mesh->current_patch->points[i][j].x = x3;
+	mesh->current_patch->points[i][j].y = y3;
+    }
+}
+slim_hidden_def (cairo_mesh_pattern_curve_to);
+
+/**
+ * cairo_mesh_pattern_line_to:
+ * @pattern: a #cairo_pattern_t
+ * @x: the X coordinate of the end of the new line
+ * @y: the Y coordinate of the end of the new line
+ *
+ * Adds a line to the current patch from the current point to position
+ * (@x, @y) in pattern-space coordinates.
+ *
+ * If there is no current point before the call to
+ * cairo_mesh_pattern_line_to() this function will behave as
+ * cairo_mesh_pattern_move_to(@pattern, @x, @y).
+ *
+ * After this call the current point will be (@x, @y).
+ *
+ * Note: If @pattern is not a mesh pattern then @pattern will be put
+ * into an error status with a status of
+ * %CAIRO_STATUS_PATTERN_TYPE_MISMATCH. If @pattern has no current
+ * patch or the current patch already has 4 sides, @pattern will be
+ * put into an error status with a status of
+ * %CAIRO_STATUS_INVALID_MESH_CONSTRUCTION.
+ *
+ * Since: 1.12
+ **/
+void
+cairo_mesh_pattern_line_to (cairo_pattern_t *pattern,
+			    double x, double y)
+{
+    cairo_mesh_pattern_t *mesh;
+    cairo_point_double_t last_point;
+    int last_point_idx, i, j;
+
+    if (unlikely (pattern->status))
+	return;
+
+    if (unlikely (pattern->type != CAIRO_PATTERN_TYPE_MESH)) {
+	_cairo_pattern_set_error (pattern, CAIRO_STATUS_PATTERN_TYPE_MISMATCH);
+	return;
+    }
+
+    mesh = (cairo_mesh_pattern_t *) pattern;
+    if (unlikely (!mesh->current_patch)) {
+	_cairo_pattern_set_error (pattern, CAIRO_STATUS_INVALID_MESH_CONSTRUCTION);
+	return;
+    }
+
+    if (unlikely (mesh->current_side == 3)) {
+	_cairo_pattern_set_error (pattern, CAIRO_STATUS_INVALID_MESH_CONSTRUCTION);
+	return;
+    }
+
+    if (mesh->current_side == -2) {
+	cairo_mesh_pattern_move_to (pattern, x, y);
+	return;
+    }
+
+    last_point_idx = 3 * (mesh->current_side + 1);
+    i = mesh_path_point_i[last_point_idx];
+    j = mesh_path_point_j[last_point_idx];
+
+    last_point = mesh->current_patch->points[i][j];
+
+    cairo_mesh_pattern_curve_to (pattern,
+				 (2 * last_point.x + x) * (1. / 3),
+				 (2 * last_point.y + y) * (1. / 3),
+				 (last_point.x + 2 * x) * (1. / 3),
+				 (last_point.y + 2 * y) * (1. / 3),
+				 x, y);
+}
+slim_hidden_def (cairo_mesh_pattern_line_to);
+
+/**
+ * cairo_mesh_pattern_move_to:
+ * @pattern: a #cairo_pattern_t
+ * @x: the X coordinate of the new position
+ * @y: the Y coordinate of the new position
+ *
+ * Define the first point of the current patch in a mesh pattern.
+ *
+ * After this call the current point will be (@x, @y).
+ *
+ * Note: If @pattern is not a mesh pattern then @pattern will be put
+ * into an error status with a status of
+ * %CAIRO_STATUS_PATTERN_TYPE_MISMATCH. If @pattern has no current
+ * patch or the current patch already has at least one side, @pattern
+ * will be put into an error status with a status of
+ * %CAIRO_STATUS_INVALID_MESH_CONSTRUCTION.
+ *
+ * Since: 1.12
+ **/
+void
+cairo_mesh_pattern_move_to (cairo_pattern_t *pattern,
+			    double x, double y)
+{
+    cairo_mesh_pattern_t *mesh;
+
+    if (unlikely (pattern->status))
+	return;
+
+    if (unlikely (pattern->type != CAIRO_PATTERN_TYPE_MESH)) {
+	_cairo_pattern_set_error (pattern, CAIRO_STATUS_PATTERN_TYPE_MISMATCH);
+	return;
+    }
+
+    mesh = (cairo_mesh_pattern_t *) pattern;
+    if (unlikely (!mesh->current_patch)) {
+	_cairo_pattern_set_error (pattern, CAIRO_STATUS_INVALID_MESH_CONSTRUCTION);
+	return;
+    }
+
+    if (unlikely (mesh->current_side >= 0)) {
+	_cairo_pattern_set_error (pattern, CAIRO_STATUS_INVALID_MESH_CONSTRUCTION);
+	return;
+    }
+
+    mesh->current_side = -1;
+    mesh->current_patch->points[0][0].x = x;
+    mesh->current_patch->points[0][0].y = y;
+}
+slim_hidden_def (cairo_mesh_pattern_move_to);
+
+/**
+ * cairo_mesh_pattern_set_control_point:
+ * @pattern: a #cairo_pattern_t
+ * @point_num: the control point to set the position for
+ * @x: the X coordinate of the control point
+ * @y: the Y coordinate of the control point
+ *
+ * Set an internal control point of the current patch.
+ *
+ * Valid values for @point_num are from 0 to 3 and identify the
+ * control points as explained in cairo_pattern_create_mesh().
+ *
+ * Note: If @pattern is not a mesh pattern then @pattern will be put
+ * into an error status with a status of
+ * %CAIRO_STATUS_PATTERN_TYPE_MISMATCH. If @point_num is not valid,
+ * @pattern will be put into an error status with a status of
+ * %CAIRO_STATUS_INVALID_INDEX.  If @pattern has no current patch,
+ * @pattern will be put into an error status with a status of
+ * %CAIRO_STATUS_INVALID_MESH_CONSTRUCTION.
+ *
+ * Since: 1.12
+ **/
+void
+cairo_mesh_pattern_set_control_point (cairo_pattern_t *pattern,
+				      unsigned int     point_num,
+				      double           x,
+				      double           y)
+{
+    cairo_mesh_pattern_t *mesh;
+    int i, j;
+
+    if (unlikely (pattern->status))
+	return;
+
+    if (unlikely (pattern->type != CAIRO_PATTERN_TYPE_MESH)) {
+	_cairo_pattern_set_error (pattern, CAIRO_STATUS_PATTERN_TYPE_MISMATCH);
+	return;
+    }
+
+    if (unlikely (point_num > 3)) {
+	_cairo_pattern_set_error (pattern, CAIRO_STATUS_INVALID_INDEX);
+	return;
+    }
+
+    mesh = (cairo_mesh_pattern_t *) pattern;
+    if (unlikely (!mesh->current_patch)) {
+	_cairo_pattern_set_error (pattern, CAIRO_STATUS_INVALID_MESH_CONSTRUCTION);
+	return;
+    }
+
+    i = mesh_control_point_i[point_num];
+    j = mesh_control_point_j[point_num];
+
+    mesh->current_patch->points[i][j].x = x;
+    mesh->current_patch->points[i][j].y = y;
+    mesh->has_control_point[point_num] = TRUE;
+}
+
+/* make room for at least one more color stop */
+static cairo_status_t
+_cairo_pattern_gradient_grow (cairo_gradient_pattern_t *pattern)
+{
+    cairo_gradient_stop_t *new_stops;
+    int old_size = pattern->stops_size;
+    int embedded_size = ARRAY_LENGTH (pattern->stops_embedded);
+    int new_size = 2 * MAX (old_size, 4);
+
+    /* we have a local buffer at pattern->stops_embedded.  try to fulfill the request
+     * from there. */
+    if (old_size < embedded_size) {
+	pattern->stops = pattern->stops_embedded;
+	pattern->stops_size = embedded_size;
+	return CAIRO_STATUS_SUCCESS;
+    }
+
+    if (CAIRO_INJECT_FAULT ())
+	return _cairo_error (CAIRO_STATUS_NO_MEMORY);
+
+    assert (pattern->n_stops <= pattern->stops_size);
+
+    if (pattern->stops == pattern->stops_embedded) {
+	new_stops = _cairo_malloc_ab (new_size, sizeof (cairo_gradient_stop_t));
+	if (new_stops)
+	    memcpy (new_stops, pattern->stops, old_size * sizeof (cairo_gradient_stop_t));
+    } else {
+	new_stops = _cairo_realloc_ab (pattern->stops,
+				       new_size,
+				       sizeof (cairo_gradient_stop_t));
+    }
+
+    if (unlikely (new_stops == NULL))
+	return _cairo_error (CAIRO_STATUS_NO_MEMORY);
+
+    pattern->stops = new_stops;
+    pattern->stops_size = new_size;
+
+    return CAIRO_STATUS_SUCCESS;
+}
+
+static void
+_cairo_mesh_pattern_set_corner_color (cairo_mesh_pattern_t *mesh,
+				      unsigned int     corner_num,
+				      double red, double green, double blue,
+				      double alpha)
+{
+    cairo_color_t *color;
+
+    assert (mesh->current_patch);
+    assert (corner_num <= 3);
+
+    color = &mesh->current_patch->colors[corner_num];
+    color->red   = red;
+    color->green = green;
+    color->blue  = blue;
+    color->alpha = alpha;
+
+    color->red_short   = _cairo_color_double_to_short (red);
+    color->green_short = _cairo_color_double_to_short (green);
+    color->blue_short  = _cairo_color_double_to_short (blue);
+    color->alpha_short = _cairo_color_double_to_short (alpha);
+
+    mesh->has_color[corner_num] = TRUE;
+}
+
+/**
+ * cairo_mesh_pattern_set_corner_color_rgb:
+ * @pattern: a #cairo_pattern_t
+ * @corner_num: the corner to set the color for
+ * @red: red component of color
+ * @green: green component of color
+ * @blue: blue component of color
+ *
+ * Sets the color of a corner of the current patch in a mesh pattern.
+ *
+ * The color is specified in the same way as in cairo_set_source_rgb().
+ *
+ * Valid values for @corner_num are from 0 to 3 and identify the
+ * corners as explained in cairo_pattern_create_mesh().
+ *
+ * Note: If @pattern is not a mesh pattern then @pattern will be put
+ * into an error status with a status of
+ * %CAIRO_STATUS_PATTERN_TYPE_MISMATCH. If @corner_num is not valid,
+ * @pattern will be put into an error status with a status of
+ * %CAIRO_STATUS_INVALID_INDEX.  If @pattern has no current patch,
+ * @pattern will be put into an error status with a status of
+ * %CAIRO_STATUS_INVALID_MESH_CONSTRUCTION.
+ *
+ * Since: 1.12
+ **/
+void
+cairo_mesh_pattern_set_corner_color_rgb (cairo_pattern_t *pattern,
+					 unsigned int     corner_num,
+					 double red, double green, double blue)
+{
+    cairo_mesh_pattern_set_corner_color_rgba (pattern, corner_num, red, green, blue, 1.0);
+}
+
+/**
+ * cairo_mesh_pattern_set_corner_color_rgba:
+ * @pattern: a #cairo_pattern_t
+ * @corner_num: the corner to set the color for
+ * @red: red component of color
+ * @green: green component of color
+ * @blue: blue component of color
+ * @alpha: alpha component of color
+ *
+ * Sets the color of a corner of the current patch in a mesh pattern.
+ *
+ * The color is specified in the same way as in cairo_set_source_rgba().
+ *
+ * Valid values for @corner_num are from 0 to 3 and identify the
+ * corners as explained in cairo_pattern_create_mesh().
+ *
+ * Note: If @pattern is not a mesh pattern then @pattern will be put
+ * into an error status with a status of
+ * %CAIRO_STATUS_PATTERN_TYPE_MISMATCH. If @corner_num is not valid,
+ * @pattern will be put into an error status with a status of
+ * %CAIRO_STATUS_INVALID_INDEX.  If @pattern has no current patch,
+ * @pattern will be put into an error status with a status of
+ * %CAIRO_STATUS_INVALID_MESH_CONSTRUCTION.
+ *
+ * Since: 1.12
+ **/
+void
+cairo_mesh_pattern_set_corner_color_rgba (cairo_pattern_t *pattern,
+					  unsigned int     corner_num,
+					  double red, double green, double blue,
+					  double alpha)
+{
+    cairo_mesh_pattern_t *mesh;
+
+    if (unlikely (pattern->status))
+	return;
+
+    if (unlikely (pattern->type != CAIRO_PATTERN_TYPE_MESH)) {
+	_cairo_pattern_set_error (pattern, CAIRO_STATUS_PATTERN_TYPE_MISMATCH);
+	return;
+    }
+
+    if (unlikely (corner_num > 3)) {
+	_cairo_pattern_set_error (pattern, CAIRO_STATUS_INVALID_INDEX);
+	return;
+    }
+
+    mesh = (cairo_mesh_pattern_t *) pattern;
+    if (unlikely (!mesh->current_patch)) {
+	_cairo_pattern_set_error (pattern, CAIRO_STATUS_INVALID_MESH_CONSTRUCTION);
+	return;
+    }
+
+    red    = _cairo_restrict_value (red,    0.0, 1.0);
+    green  = _cairo_restrict_value (green,  0.0, 1.0);
+    blue   = _cairo_restrict_value (blue,   0.0, 1.0);
+    alpha  = _cairo_restrict_value (alpha,  0.0, 1.0);
+
+    _cairo_mesh_pattern_set_corner_color (mesh, corner_num, red, green, blue, alpha);
+}
+slim_hidden_def (cairo_mesh_pattern_set_corner_color_rgba);
+
+static void
+_cairo_pattern_add_color_stop (cairo_gradient_pattern_t	*pattern,
+			       double			 offset,
+			       double			 red,
+			       double			 green,
+			       double			 blue,
+			       double			 alpha)
+{
+    cairo_gradient_stop_t *stops;
+    unsigned int	   i;
+
+    if (pattern->n_stops >= pattern->stops_size) {
+        cairo_status_t status = _cairo_pattern_gradient_grow (pattern);
+	if (unlikely (status)) {
+	    status = _cairo_pattern_set_error (&pattern->base, status);
+	    return;
+	}
+    }
+
+    stops = pattern->stops;
+
+    for (i = 0; i < pattern->n_stops; i++)
+    {
+	if (offset < stops[i].offset)
+	{
+	    memmove (&stops[i + 1], &stops[i],
+		     sizeof (cairo_gradient_stop_t) * (pattern->n_stops - i));
+
+	    break;
+	}
+    }
+
+    stops[i].offset = offset;
+
+    stops[i].color.red   = red;
+    stops[i].color.green = green;
+    stops[i].color.blue  = blue;
+    stops[i].color.alpha = alpha;
+
+    stops[i].color.red_short   = _cairo_color_double_to_short (red);
+    stops[i].color.green_short = _cairo_color_double_to_short (green);
+    stops[i].color.blue_short  = _cairo_color_double_to_short (blue);
+    stops[i].color.alpha_short = _cairo_color_double_to_short (alpha);
+
+    pattern->n_stops++;
+}
+
+/**
+ * cairo_pattern_add_color_stop_rgb:
+ * @pattern: a #cairo_pattern_t
+ * @offset: an offset in the range [0.0 .. 1.0]
+ * @red: red component of color
+ * @green: green component of color
+ * @blue: blue component of color
+ *
+ * Adds an opaque color stop to a gradient pattern. The offset
+ * specifies the location along the gradient's control vector. For
+ * example, a linear gradient's control vector is from (x0,y0) to
+ * (x1,y1) while a radial gradient's control vector is from any point
+ * on the start circle to the corresponding point on the end circle.
+ *
+ * The color is specified in the same way as in cairo_set_source_rgb().
+ *
+ * If two (or more) stops are specified with identical offset values,
+ * they will be sorted according to the order in which the stops are
+ * added, (stops added earlier will compare less than stops added
+ * later). This can be useful for reliably making sharp color
+ * transitions instead of the typical blend.
+ *
+ *
+ * Note: If the pattern is not a gradient pattern, (eg. a linear or
+ * radial pattern), then the pattern will be put into an error status
+ * with a status of %CAIRO_STATUS_PATTERN_TYPE_MISMATCH.
+ *
+ * Since: 1.0
+ **/
+void
+cairo_pattern_add_color_stop_rgb (cairo_pattern_t *pattern,
+				  double	   offset,
+				  double	   red,
+				  double	   green,
+				  double	   blue)
+{
+    cairo_pattern_add_color_stop_rgba (pattern, offset, red, green, blue, 1.0);
+}
+
+/**
+ * cairo_pattern_add_color_stop_rgba:
+ * @pattern: a #cairo_pattern_t
+ * @offset: an offset in the range [0.0 .. 1.0]
+ * @red: red component of color
+ * @green: green component of color
+ * @blue: blue component of color
+ * @alpha: alpha component of color
+ *
+ * Adds a translucent color stop to a gradient pattern. The offset
+ * specifies the location along the gradient's control vector. For
+ * example, a linear gradient's control vector is from (x0,y0) to
+ * (x1,y1) while a radial gradient's control vector is from any point
+ * on the start circle to the corresponding point on the end circle.
+ *
+ * The color is specified in the same way as in cairo_set_source_rgba().
+ *
+ * If two (or more) stops are specified with identical offset values,
+ * they will be sorted according to the order in which the stops are
+ * added, (stops added earlier will compare less than stops added
+ * later). This can be useful for reliably making sharp color
+ * transitions instead of the typical blend.
+ *
+ * Note: If the pattern is not a gradient pattern, (eg. a linear or
+ * radial pattern), then the pattern will be put into an error status
+ * with a status of %CAIRO_STATUS_PATTERN_TYPE_MISMATCH.
+ *
+ * Since: 1.0
+ **/
+void
+cairo_pattern_add_color_stop_rgba (cairo_pattern_t *pattern,
+				   double	   offset,
+				   double	   red,
+				   double	   green,
+				   double	   blue,
+				   double	   alpha)
+{
+    if (pattern->status)
+	return;
+
+    if (pattern->type != CAIRO_PATTERN_TYPE_LINEAR &&
+	pattern->type != CAIRO_PATTERN_TYPE_RADIAL)
+    {
+	_cairo_pattern_set_error (pattern, CAIRO_STATUS_PATTERN_TYPE_MISMATCH);
+	return;
+    }
+
+    offset = _cairo_restrict_value (offset, 0.0, 1.0);
+    red    = _cairo_restrict_value (red,    0.0, 1.0);
+    green  = _cairo_restrict_value (green,  0.0, 1.0);
+    blue   = _cairo_restrict_value (blue,   0.0, 1.0);
+    alpha  = _cairo_restrict_value (alpha,  0.0, 1.0);
+
+    _cairo_pattern_add_color_stop ((cairo_gradient_pattern_t *) pattern,
+				   offset, red, green, blue, alpha);
+}
+slim_hidden_def (cairo_pattern_add_color_stop_rgba);
+
+/**
+ * cairo_pattern_set_matrix:
+ * @pattern: a #cairo_pattern_t
+ * @matrix: a #cairo_matrix_t
+ *
+ * Sets the pattern's transformation matrix to @matrix. This matrix is
+ * a transformation from user space to pattern space.
+ *
+ * When a pattern is first created it always has the identity matrix
+ * for its transformation matrix, which means that pattern space is
+ * initially identical to user space.
+ *
+ * Important: Please note that the direction of this transformation
+ * matrix is from user space to pattern space. This means that if you
+ * imagine the flow from a pattern to user space (and on to device
+ * space), then coordinates in that flow will be transformed by the
+ * inverse of the pattern matrix.
+ *
+ * For example, if you want to make a pattern appear twice as large as
+ * it does by default the correct code to use is:
+ *
+ * <informalexample><programlisting>
+ * cairo_matrix_init_scale (&amp;matrix, 0.5, 0.5);
+ * cairo_pattern_set_matrix (pattern, &amp;matrix);
+ * </programlisting></informalexample>
+ *
+ * Meanwhile, using values of 2.0 rather than 0.5 in the code above
+ * would cause the pattern to appear at half of its default size.
+ *
+ * Also, please note the discussion of the user-space locking
+ * semantics of cairo_set_source().
+ *
+ * Since: 1.0
+ **/
+void
+cairo_pattern_set_matrix (cairo_pattern_t      *pattern,
+			  const cairo_matrix_t *matrix)
+{
+    cairo_matrix_t inverse;
+    cairo_status_t status;
+
+    if (pattern->status)
+	return;
+
+    if (memcmp (&pattern->matrix, matrix, sizeof (cairo_matrix_t)) == 0)
+	return;
+
+    pattern->matrix = *matrix;
+    _cairo_pattern_notify_observers (pattern, CAIRO_PATTERN_NOTIFY_MATRIX);
+
+    inverse = *matrix;
+    status = cairo_matrix_invert (&inverse);
+    if (unlikely (status))
+	status = _cairo_pattern_set_error (pattern, status);
+}
+slim_hidden_def (cairo_pattern_set_matrix);
+
+/**
+ * cairo_pattern_get_matrix:
+ * @pattern: a #cairo_pattern_t
+ * @matrix: return value for the matrix
+ *
+ * Stores the pattern's transformation matrix into @matrix.
+ *
+ * Since: 1.0
+ **/
+void
+cairo_pattern_get_matrix (cairo_pattern_t *pattern, cairo_matrix_t *matrix)
+{
+    *matrix = pattern->matrix;
+}
+
+/**
+ * cairo_pattern_set_filter:
+ * @pattern: a #cairo_pattern_t
+ * @filter: a #cairo_filter_t describing the filter to use for resizing
+ * the pattern
+ *
+ * Sets the filter to be used for resizing when using this pattern.
+ * See #cairo_filter_t for details on each filter.
+ *
+ * * Note that you might want to control filtering even when you do not
+ * have an explicit #cairo_pattern_t object, (for example when using
+ * cairo_set_source_surface()). In these cases, it is convenient to
+ * use cairo_get_source() to get access to the pattern that cairo
+ * creates implicitly. For example:
+ *
+ * <informalexample><programlisting>
+ * cairo_set_source_surface (cr, image, x, y);
+ * cairo_pattern_set_filter (cairo_get_source (cr), CAIRO_FILTER_NEAREST);
+ * </programlisting></informalexample>
+ *
+ * Since: 1.0
+ **/
+void
+cairo_pattern_set_filter (cairo_pattern_t *pattern, cairo_filter_t filter)
+{
+    if (pattern->status)
+	return;
+
+    pattern->filter = filter;
+    _cairo_pattern_notify_observers (pattern, CAIRO_PATTERN_NOTIFY_FILTER);
+}
+
+/**
+ * cairo_pattern_get_filter:
+ * @pattern: a #cairo_pattern_t
+ *
+ * Gets the current filter for a pattern.  See #cairo_filter_t
+ * for details on each filter.
+ *
+ * Return value: the current filter used for resizing the pattern.
+ *
+ * Since: 1.0
+ **/
+cairo_filter_t
+cairo_pattern_get_filter (cairo_pattern_t *pattern)
+{
+    return pattern->filter;
+}
+
+/**
+ * cairo_pattern_set_extend:
+ * @pattern: a #cairo_pattern_t
+ * @extend: a #cairo_extend_t describing how the area outside of the
+ * pattern will be drawn
+ *
+ * Sets the mode to be used for drawing outside the area of a pattern.
+ * See #cairo_extend_t for details on the semantics of each extend
+ * strategy.
+ *
+ * The default extend mode is %CAIRO_EXTEND_NONE for surface patterns
+ * and %CAIRO_EXTEND_PAD for gradient patterns.
+ *
+ * Since: 1.0
+ **/
+void
+cairo_pattern_set_extend (cairo_pattern_t *pattern, cairo_extend_t extend)
+{
+    if (pattern->status)
+	return;
+
+    pattern->extend = extend;
+    _cairo_pattern_notify_observers (pattern, CAIRO_PATTERN_NOTIFY_EXTEND);
+}
+
+/**
+ * cairo_pattern_get_extend:
+ * @pattern: a #cairo_pattern_t
+ *
+ * Gets the current extend mode for a pattern.  See #cairo_extend_t
+ * for details on the semantics of each extend strategy.
+ *
+ * Return value: the current extend strategy used for drawing the
+ * pattern.
+ *
+ * Since: 1.0
+ **/
+cairo_extend_t
+cairo_pattern_get_extend (cairo_pattern_t *pattern)
+{
+    return pattern->extend;
+}
+slim_hidden_def (cairo_pattern_get_extend);
+
+void
+_cairo_pattern_transform (cairo_pattern_t	*pattern,
+			  const cairo_matrix_t  *ctm_inverse)
+{
+    if (pattern->status)
+	return;
+
+    cairo_matrix_multiply (&pattern->matrix, ctm_inverse, &pattern->matrix);
+}
+
+static cairo_bool_t
+_linear_pattern_is_degenerate (const cairo_linear_pattern_t *linear)
+{
+    return fabs (linear->pd1.x - linear->pd2.x) < DBL_EPSILON &&
+	   fabs (linear->pd1.y - linear->pd2.y) < DBL_EPSILON;
+}
+
+static cairo_bool_t
+_radial_pattern_is_degenerate (const cairo_radial_pattern_t *radial)
+{
+    /* A radial pattern is considered degenerate if it can be
+     * represented as a solid or clear pattern.  This corresponds to
+     * one of the two cases:
+     *
+     * 1) The radii are both very small:
+     *      |dr| < DBL_EPSILON && min (r0, r1) < DBL_EPSILON
+     *
+     * 2) The two circles have about the same radius and are very
+     *    close to each other (approximately a cylinder gradient that
+     *    doesn't move with the parameter):
+     *      |dr| < DBL_EPSILON && max (|dx|, |dy|) < 2 * DBL_EPSILON
+     *
+     * These checks are consistent with the assumptions used in
+     * _cairo_radial_pattern_box_to_parameter ().
+     */
+
+    return fabs (radial->cd1.radius - radial->cd2.radius) < DBL_EPSILON &&
+	(MIN (radial->cd1.radius, radial->cd2.radius) < DBL_EPSILON ||
+	 MAX (fabs (radial->cd1.center.x - radial->cd2.center.x),
+	      fabs (radial->cd1.center.y - radial->cd2.center.y)) < 2 * DBL_EPSILON);
+}
+
+static void
+_cairo_linear_pattern_box_to_parameter (const cairo_linear_pattern_t *linear,
+					double x0, double y0,
+					double x1, double y1,
+					double range[2])
+{
+    double t0, tdx, tdy;
+    double p1x, p1y, pdx, pdy, invsqnorm;
+
+    assert (! _linear_pattern_is_degenerate (linear));
+
+    /*
+     * Linear gradients are othrogonal to the line passing through
+     * their extremes. Because of convexity, the parameter range can
+     * be computed as the convex hull (one the real line) of the
+     * parameter values of the 4 corners of the box.
+     *
+     * The parameter value t for a point (x,y) can be computed as:
+     *
+     *   t = (p2 - p1) . (x,y) / |p2 - p1|^2
+     *
+     * t0  is the t value for the top left corner
+     * tdx is the difference between left and right corners
+     * tdy is the difference between top and bottom corners
+     */
+
+    p1x = linear->pd1.x;
+    p1y = linear->pd1.y;
+    pdx = linear->pd2.x - p1x;
+    pdy = linear->pd2.y - p1y;
+    invsqnorm = 1.0 / (pdx * pdx + pdy * pdy);
+    pdx *= invsqnorm;
+    pdy *= invsqnorm;
+
+    t0 = (x0 - p1x) * pdx + (y0 - p1y) * pdy;
+    tdx = (x1 - x0) * pdx;
+    tdy = (y1 - y0) * pdy;
+
+    /*
+     * Because of the linearity of the t value, tdx can simply be
+     * added the t0 to move along the top edge. After this, range[0]
+     * and range[1] represent the parameter range for the top edge, so
+     * extending it to include the whole box simply requires adding
+     * tdy to the correct extreme.
+     */
+
+    range[0] = range[1] = t0;
+    if (tdx < 0)
+	range[0] += tdx;
+    else
+	range[1] += tdx;
+
+    if (tdy < 0)
+	range[0] += tdy;
+    else
+	range[1] += tdy;
+}
+
+static cairo_bool_t
+_extend_range (double range[2], double value, cairo_bool_t valid)
+{
+    if (!valid)
+	range[0] = range[1] = value;
+    else if (value < range[0])
+	range[0] = value;
+    else if (value > range[1])
+	range[1] = value;
+
+    return TRUE;
+}
+
+/*
+ * _cairo_radial_pattern_focus_is_inside:
+ *
+ * Returns %TRUE if and only if the focus point exists and is
+ * contained in one of the two extreme circles. This condition is
+ * equivalent to one of the two extreme circles being completely
+ * contained in the other one.
+ *
+ * Note: if the focus is on the border of one of the two circles (in
+ * which case the circles are tangent in the focus point), it is not
+ * considered as contained in the circle, hence this function returns
+ * %FALSE.
+ *
+ */
+cairo_bool_t
+_cairo_radial_pattern_focus_is_inside (const cairo_radial_pattern_t *radial)
+{
+    double cx, cy, cr, dx, dy, dr;
+
+    cx = radial->cd1.center.x;
+    cy = radial->cd1.center.y;
+    cr = radial->cd1.radius;
+    dx = radial->cd2.center.x - cx;
+    dy = radial->cd2.center.y - cy;
+    dr = radial->cd2.radius   - cr;
+
+    return dx*dx + dy*dy < dr*dr;
+}
+
+static void
+_cairo_radial_pattern_box_to_parameter (const cairo_radial_pattern_t *radial,
+					double x0, double y0,
+					double x1, double y1,
+					double tolerance,
+					double range[2])
+{
+    double cx, cy, cr, dx, dy, dr;
+    double a, x_focus, y_focus;
+    double mindr, minx, miny, maxx, maxy;
+    cairo_bool_t valid;
+
+    assert (! _radial_pattern_is_degenerate (radial));
+    assert (x0 < x1);
+    assert (y0 < y1);
+
+    tolerance = MAX (tolerance, DBL_EPSILON);
+
+    range[0] = range[1] = 0;
+    valid = FALSE;
+
+    x_focus = y_focus = 0; /* silence gcc */
+
+    cx = radial->cd1.center.x;
+    cy = radial->cd1.center.y;
+    cr = radial->cd1.radius;
+    dx = radial->cd2.center.x - cx;
+    dy = radial->cd2.center.y - cy;
+    dr = radial->cd2.radius   - cr;
+
+    /* translate by -(cx, cy) to simplify computations */
+    x0 -= cx;
+    y0 -= cy;
+    x1 -= cx;
+    y1 -= cy;
+
+    /* enlarge boundaries slightly to avoid rounding problems in the
+     * parameter range computation */
+    x0 -= DBL_EPSILON;
+    y0 -= DBL_EPSILON;
+    x1 += DBL_EPSILON;
+    y1 += DBL_EPSILON;
+
+    /* enlarge boundaries even more to avoid rounding problems when
+     * testing if a point belongs to the box */
+    minx = x0 - DBL_EPSILON;
+    miny = y0 - DBL_EPSILON;
+    maxx = x1 + DBL_EPSILON;
+    maxy = y1 + DBL_EPSILON;
+
+    /* we dont' allow negative radiuses, so we will be checking that
+     * t*dr >= mindr to consider t valid */
+    mindr = -(cr + DBL_EPSILON);
+
+    /*
+     * After the previous transformations, the start circle is
+     * centered in the origin and has radius cr. A 1-unit change in
+     * the t parameter corresponds to dx,dy,dr changes in the x,y,r of
+     * the circle (center coordinates, radius).
+     *
+     * To compute the minimum range needed to correctly draw the
+     * pattern, we start with an empty range and extend it to include
+     * the circles touching the bounding box or within it.
+     */
+
+    /*
+     * Focus, the point where the circle has radius == 0.
+     *
+     * r = cr + t * dr = 0
+     * t = -cr / dr
+     *
+     * If the radius is constant (dr == 0) there is no focus (the
+     * gradient represents a cylinder instead of a cone).
+     */
+    if (fabs (dr) >= DBL_EPSILON) {
+	double t_focus;
+
+	t_focus = -cr / dr;
+	x_focus = t_focus * dx;
+	y_focus = t_focus * dy;
+	if (minx <= x_focus && x_focus <= maxx &&
+	    miny <= y_focus && y_focus <= maxy)
+	{
+	    valid = _extend_range (range, t_focus, valid);
+	}
+    }
+
+    /*
+     * Circles externally tangent to box edges.
+     *
+     * All circles have center in (dx, dy) * t
+     *
+     * If the circle is tangent to the line defined by the edge of the
+     * box, then at least one of the following holds true:
+     *
+     *   (dx*t) + (cr + dr*t) == x0 (left   edge)
+     *   (dx*t) - (cr + dr*t) == x1 (right  edge)
+     *   (dy*t) + (cr + dr*t) == y0 (top    edge)
+     *   (dy*t) - (cr + dr*t) == y1 (bottom edge)
+     *
+     * The solution is only valid if the tangent point is actually on
+     * the edge, i.e. if its y coordinate is in [y0,y1] for left/right
+     * edges and if its x coordinate is in [x0,x1] for top/bottom
+     * edges.
+     *
+     * For the first equation:
+     *
+     *   (dx + dr) * t = x0 - cr
+     *   t = (x0 - cr) / (dx + dr)
+     *   y = dy * t
+     *
+     * in the code this becomes:
+     *
+     *   t_edge = (num) / (den)
+     *   v = (delta) * t_edge
+     *
+     * If the denominator in t is 0, the pattern is tangent to a line
+     * parallel to the edge under examination. The corner-case where
+     * the boundary line is the same as the edge is handled by the
+     * focus point case and/or by the a==0 case.
+     */
+#define T_EDGE(num,den,delta,lower,upper)				\
+    if (fabs (den) >= DBL_EPSILON) {					\
+	double t_edge, v;						\
+									\
+	t_edge = (num) / (den);						\
+	v = t_edge * (delta);						\
+	if (t_edge * dr >= mindr && (lower) <= v && v <= (upper))	\
+	    valid = _extend_range (range, t_edge, valid);		\
+    }
+
+    /* circles tangent (externally) to left/right/top/bottom edge */
+    T_EDGE (x0 - cr, dx + dr, dy, miny, maxy);
+    T_EDGE (x1 + cr, dx - dr, dy, miny, maxy);
+    T_EDGE (y0 - cr, dy + dr, dx, minx, maxx);
+    T_EDGE (y1 + cr, dy - dr, dx, minx, maxx);
+
+#undef T_EDGE
+
+    /*
+     * Circles passing through a corner.
+     *
+     * A circle passing through the point (x,y) satisfies:
+     *
+     * (x-t*dx)^2 + (y-t*dy)^2 == (cr + t*dr)^2
+     *
+     * If we set:
+     *   a = dx^2 + dy^2 - dr^2
+     *   b = x*dx + y*dy + cr*dr
+     *   c = x^2 + y^2 - cr^2
+     * we have:
+     *   a*t^2 - 2*b*t + c == 0
+     */
+    a = dx * dx + dy * dy - dr * dr;
+    if (fabs (a) < DBL_EPSILON * DBL_EPSILON) {
+	double b, maxd2;
+
+	/* Ensure that gradients with both a and dr small are
+	 * considered degenerate.
+	 * The floating point version of the degeneracy test implemented
+	 * in _radial_pattern_is_degenerate() is:
+	 *
+	 *  1) The circles are practically the same size:
+	 *     |dr| < DBL_EPSILON
+	 *  AND
+	 *  2a) The circles are both very small:
+	 *      min (r0, r1) < DBL_EPSILON
+	 *   OR
+	 *  2b) The circles are very close to each other:
+	 *      max (|dx|, |dy|) < 2 * DBL_EPSILON
+	 *
+	 * Assuming that the gradient is not degenerate, we want to
+	 * show that |a| < DBL_EPSILON^2 implies |dr| >= DBL_EPSILON.
+	 *
+	 * If the gradient is not degenerate yet it has |dr| <
+	 * DBL_EPSILON, (2b) is false, thus:
+	 *
+	 *   max (|dx|, |dy|) >= 2*DBL_EPSILON
+	 * which implies:
+	 *   4*DBL_EPSILON^2 <= max (|dx|, |dy|)^2 <= dx^2 + dy^2
+	 *
+	 * From the definition of a, we get:
+	 *   a = dx^2 + dy^2 - dr^2 < DBL_EPSILON^2
+	 *   dx^2 + dy^2 - DBL_EPSILON^2 < dr^2
+	 *   3*DBL_EPSILON^2 < dr^2
+	 *
+	 * which is inconsistent with the hypotheses, thus |dr| <
+	 * DBL_EPSILON is false or the gradient is degenerate.
+	 */
+	assert (fabs (dr) >= DBL_EPSILON);
+
+	/*
+	 * If a == 0, all the circles are tangent to a line in the
+	 * focus point. If this line is within the box extents, we
+	 * should add the circle with infinite radius, but this would
+	 * make the range unbounded, so we add the smallest circle whose
+	 * distance to the desired (degenerate) circle within the
+	 * bounding box does not exceed tolerance.
+	 *
+	 * The equation of the line is b==0, i.e.:
+	 *   x*dx + y*dy + cr*dr == 0
+	 *
+	 * We compute the intersection of the line with the box and
+	 * keep the intersection with maximum square distance (maxd2)
+	 * from the focus point.
+	 *
+	 * In the code the intersection is represented in another
+	 * coordinate system, whose origin is the focus point and
+	 * which has a u,v axes, which are respectively orthogonal and
+	 * parallel to the edge being intersected.
+	 *
+	 * The intersection is valid only if it belongs to the box,
+	 * otherwise it is ignored.
+	 *
+	 * For example:
+	 *
+	 *   y = y0
+	 *   x*dx + y0*dy + cr*dr == 0
+	 *   x = -(y0*dy + cr*dr) / dx
+	 *
+	 * which in (u,v) is:
+	 *   u = y0 - y_focus
+	 *   v = -(y0*dy + cr*dr) / dx - x_focus
+	 *
+	 * In the code:
+	 *   u = (edge) - (u_origin)
+	 *   v = -((edge) * (delta) + cr*dr) / (den) - v_focus
+	 */
+#define T_EDGE(edge,delta,den,lower,upper,u_origin,v_origin)	\
+	if (fabs (den) >= DBL_EPSILON) {			\
+	    double v;						\
+								\
+	    v = -((edge) * (delta) + cr * dr) / (den);		\
+	    if ((lower) <= v && v <= (upper)) {			\
+		double u, d2;					\
+								\
+		u = (edge) - (u_origin);			\
+		v -= (v_origin);				\
+		d2 = u*u + v*v;					\
+		if (maxd2 < d2)					\
+		    maxd2 = d2;					\
+	    }							\
+	}
+
+	maxd2 = 0;
+
+	/* degenerate circles (lines) passing through each edge */
+	T_EDGE (y0, dy, dx, minx, maxx, y_focus, x_focus);
+	T_EDGE (y1, dy, dx, minx, maxx, y_focus, x_focus);
+	T_EDGE (x0, dx, dy, miny, maxy, x_focus, y_focus);
+	T_EDGE (x1, dx, dy, miny, maxy, x_focus, y_focus);
+
+#undef T_EDGE
+
+	/*
+	 * The limit circle can be transformed rigidly to the y=0 line
+	 * and the circles tangent to it in (0,0) are:
+	 *
+	 *   x^2 + (y-r)^2 = r^2  <=>  x^2 + y^2 - 2*y*r = 0
+	 *
+	 * y is the distance from the line, in our case tolerance;
+	 * x is the distance along the line, i.e. sqrt(maxd2),
+	 * so:
+	 *
+	 *   r = cr + dr * t = (maxd2 + tolerance^2) / (2*tolerance)
+	 *   t = (r - cr) / dr =
+	 *       (maxd2 + tolerance^2 - 2*tolerance*cr) / (2*tolerance*dr)
+	 */
+	if (maxd2 > 0) {
+	    double t_limit = maxd2 + tolerance*tolerance - 2*tolerance*cr;
+	    t_limit /= 2 * tolerance * dr;
+	    valid = _extend_range (range, t_limit, valid);
+	}
+
+	/*
+	 * Nondegenerate, nonlimit circles passing through the corners.
+	 *
+	 * a == 0 && a*t^2 - 2*b*t + c == 0
+	 *
+	 * t = c / (2*b)
+	 *
+	 * The b == 0 case has just been handled, so we only have to
+	 * compute this if b != 0.
+	 */
+#define T_CORNER(x,y)							\
+	b = (x) * dx + (y) * dy + cr * dr;				\
+	if (fabs (b) >= DBL_EPSILON) {					\
+	    double t_corner;						\
+	    double x2 = (x) * (x);					\
+	    double y2 = (y) * (y);					\
+	    double cr2 = (cr) * (cr);					\
+	    double c = x2 + y2 - cr2;					\
+	    								\
+	    t_corner = 0.5 * c / b;					\
+	    if (t_corner * dr >= mindr)					\
+		valid = _extend_range (range, t_corner, valid);		\
+	}
+
+	/* circles touching each corner */
+	T_CORNER (x0, y0);
+	T_CORNER (x0, y1);
+	T_CORNER (x1, y0);
+	T_CORNER (x1, y1);
+
+#undef T_CORNER
+    } else {
+	double inva, b, c, d;
+
+	inva = 1 / a;
+
+	/*
+	 * Nondegenerate, nonlimit circles passing through the corners.
+	 *
+	 * a != 0 && a*t^2 - 2*b*t + c == 0
+	 *
+	 * t = (b +- sqrt (b*b - a*c)) / a
+	 *
+	 * If the argument of sqrt() is negative, then no circle
+	 * passes through the corner.
+	 */
+#define T_CORNER(x,y)							\
+	b = (x) * dx + (y) * dy + cr * dr;				\
+	c = (x) * (x) + (y) * (y) - cr * cr;				\
+	d = b * b - a * c;						\
+	if (d >= 0) {							\
+	    double t_corner;						\
+									\
+	    d = sqrt (d);						\
+	    t_corner = (b + d) * inva;					\
+	    if (t_corner * dr >= mindr)					\
+		valid = _extend_range (range, t_corner, valid);		\
+	    t_corner = (b - d) * inva;					\
+	    if (t_corner * dr >= mindr)					\
+		valid = _extend_range (range, t_corner, valid);		\
+	}
+
+	/* circles touching each corner */
+	T_CORNER (x0, y0);
+	T_CORNER (x0, y1);
+	T_CORNER (x1, y0);
+	T_CORNER (x1, y1);
+
+#undef T_CORNER
+    }
+}
+
+/**
+ * _cairo_gradient_pattern_box_to_parameter:
+ *
+ * Compute a interpolation range sufficient to draw (within the given
+ * tolerance) the gradient in the given box getting the same result as
+ * using the (-inf, +inf) range.
+ *
+ * Assumes that the pattern is not degenerate. This can be guaranteed
+ * by simplifying it to a solid clear if _cairo_pattern_is_clear or to
+ * a solid color if _cairo_gradient_pattern_is_solid.
+ *
+ * The range isn't guaranteed to be minimal, but it tries to.
+ **/
+void
+_cairo_gradient_pattern_box_to_parameter (const cairo_gradient_pattern_t *gradient,
+					  double x0, double y0,
+					  double x1, double y1,
+					  double tolerance,
+					  double out_range[2])
+{
+    assert (gradient->base.type == CAIRO_PATTERN_TYPE_LINEAR ||
+	    gradient->base.type == CAIRO_PATTERN_TYPE_RADIAL);
+
+    if (gradient->base.type == CAIRO_PATTERN_TYPE_LINEAR) {
+	_cairo_linear_pattern_box_to_parameter ((cairo_linear_pattern_t *) gradient,
+						x0, y0, x1, y1, out_range);
+    } else {
+	_cairo_radial_pattern_box_to_parameter ((cairo_radial_pattern_t *) gradient,
+						x0, y0, x1, y1, tolerance, out_range);
+    }
+}
+
+/**
+ * _cairo_gradient_pattern_interpolate:
+ *
+ * Interpolate between the start and end objects of linear or radial
+ * gradients.  The interpolated object is stored in out_circle, with
+ * the radius being zero in the linear gradient case.
+ **/
+void
+_cairo_gradient_pattern_interpolate (const cairo_gradient_pattern_t *gradient,
+				     double			     t,
+				     cairo_circle_double_t	    *out_circle)
+{
+    assert (gradient->base.type == CAIRO_PATTERN_TYPE_LINEAR ||
+	    gradient->base.type == CAIRO_PATTERN_TYPE_RADIAL);
+
+#define lerp(a,b) (a)*(1-t) + (b)*t
+
+    if (gradient->base.type == CAIRO_PATTERN_TYPE_LINEAR) {
+	cairo_linear_pattern_t *linear = (cairo_linear_pattern_t *) gradient;
+	out_circle->center.x = lerp (linear->pd1.x, linear->pd2.x);
+	out_circle->center.y = lerp (linear->pd1.y, linear->pd2.y);
+	out_circle->radius = 0;
+    } else {
+	cairo_radial_pattern_t *radial = (cairo_radial_pattern_t *) gradient;
+	out_circle->center.x = lerp (radial->cd1.center.x, radial->cd2.center.x);
+	out_circle->center.y = lerp (radial->cd1.center.y, radial->cd2.center.y);
+	out_circle->radius   = lerp (radial->cd1.radius  , radial->cd2.radius);
+    }
+
+#undef lerp
+}
+
+
+/**
+ * _cairo_gradient_pattern_fit_to_range:
+ *
+ * Scale the extremes of a gradient to guarantee that the coordinates
+ * and their deltas are within the range (-max_value, max_value). The
+ * new extremes are stored in out_circle.
+ *
+ * The pattern matrix is scaled to guarantee that the aspect of the
+ * gradient is the same and the result is stored in out_matrix.
+ *
+ **/
+void
+_cairo_gradient_pattern_fit_to_range (const cairo_gradient_pattern_t *gradient,
+				      double			      max_value,
+				      cairo_matrix_t                 *out_matrix,
+				      cairo_circle_double_t	      out_circle[2])
+{
+    double dim;
+
+    assert (gradient->base.type == CAIRO_PATTERN_TYPE_LINEAR ||
+	    gradient->base.type == CAIRO_PATTERN_TYPE_RADIAL);
+
+    if (gradient->base.type == CAIRO_PATTERN_TYPE_LINEAR) {
+	cairo_linear_pattern_t *linear = (cairo_linear_pattern_t *) gradient;
+
+	out_circle[0].center = linear->pd1;
+	out_circle[0].radius = 0;
+	out_circle[1].center = linear->pd2;
+	out_circle[1].radius = 0;
+
+	dim = fabs (linear->pd1.x);
+	dim = MAX (dim, fabs (linear->pd1.y));
+	dim = MAX (dim, fabs (linear->pd2.x));
+	dim = MAX (dim, fabs (linear->pd2.y));
+	dim = MAX (dim, fabs (linear->pd1.x - linear->pd2.x));
+	dim = MAX (dim, fabs (linear->pd1.y - linear->pd2.y));
+    } else {
+	cairo_radial_pattern_t *radial = (cairo_radial_pattern_t *) gradient;
+
+	out_circle[0] = radial->cd1;
+	out_circle[1] = radial->cd2;
+
+	dim = fabs (radial->cd1.center.x);
+	dim = MAX (dim, fabs (radial->cd1.center.y));
+	dim = MAX (dim, fabs (radial->cd1.radius));
+	dim = MAX (dim, fabs (radial->cd2.center.x));
+	dim = MAX (dim, fabs (radial->cd2.center.y));
+	dim = MAX (dim, fabs (radial->cd2.radius));
+	dim = MAX (dim, fabs (radial->cd1.center.x - radial->cd2.center.x));
+	dim = MAX (dim, fabs (radial->cd1.center.y - radial->cd2.center.y));
+	dim = MAX (dim, fabs (radial->cd1.radius   - radial->cd2.radius));
+    }
+
+    if (unlikely (dim > max_value)) {
+	cairo_matrix_t scale;
+
+	dim = max_value / dim;
+
+	out_circle[0].center.x *= dim;
+	out_circle[0].center.y *= dim;
+	out_circle[0].radius   *= dim;
+	out_circle[1].center.x *= dim;
+	out_circle[1].center.y *= dim;
+	out_circle[1].radius   *= dim;
+
+	cairo_matrix_init_scale (&scale, dim, dim);
+	cairo_matrix_multiply (out_matrix, &gradient->base.matrix, &scale);
+    } else {
+	*out_matrix = gradient->base.matrix;
+    }
+}
+
+static cairo_bool_t
+_gradient_is_clear (const cairo_gradient_pattern_t *gradient,
+		    const cairo_rectangle_int_t *extents)
+{
+    unsigned int i;
+
+    assert (gradient->base.type == CAIRO_PATTERN_TYPE_LINEAR ||
+	    gradient->base.type == CAIRO_PATTERN_TYPE_RADIAL);
+
+    if (gradient->n_stops == 0 ||
+	(gradient->base.extend == CAIRO_EXTEND_NONE &&
+	 gradient->stops[0].offset == gradient->stops[gradient->n_stops - 1].offset))
+	return TRUE;
+
+    if (gradient->base.type == CAIRO_PATTERN_TYPE_RADIAL) {
+	/* degenerate radial gradients are clear */
+	if (_radial_pattern_is_degenerate ((cairo_radial_pattern_t *) gradient))
+	    return TRUE;
+    } else if (gradient->base.extend == CAIRO_EXTEND_NONE) {
+	/* EXTEND_NONE degenerate linear gradients are clear */
+	if (_linear_pattern_is_degenerate ((cairo_linear_pattern_t *) gradient))
+	    return TRUE;
+    }
+
+    /* Check if the extents intersect the drawn part of the pattern. */
+    if (extents != NULL &&
+	(gradient->base.extend == CAIRO_EXTEND_NONE ||
+	 gradient->base.type == CAIRO_PATTERN_TYPE_RADIAL))
+    {
+	double t[2];
+
+	_cairo_gradient_pattern_box_to_parameter (gradient,
+						  extents->x,
+						  extents->y,
+						  extents->x + extents->width,
+						  extents->y + extents->height,
+						  DBL_EPSILON,
+						  t);
+
+	if (gradient->base.extend == CAIRO_EXTEND_NONE &&
+	    (t[0] >= gradient->stops[gradient->n_stops - 1].offset ||
+	     t[1] <= gradient->stops[0].offset))
+	{
+		return TRUE;
+	}
+
+	if (t[0] == t[1])
+	    return TRUE;
+    }
+
+    for (i = 0; i < gradient->n_stops; i++)
+	if (! CAIRO_COLOR_IS_CLEAR (&gradient->stops[i].color))
+	    return FALSE;
+
+    return TRUE;
+}
+
+static void
+_gradient_color_average (const cairo_gradient_pattern_t *gradient,
+			 cairo_color_t *color)
+{
+    double delta0, delta1;
+    double r, g, b, a;
+    unsigned int i, start = 1, end;
+
+    assert (gradient->n_stops > 0);
+    assert (gradient->base.extend != CAIRO_EXTEND_NONE);
+
+    if (gradient->n_stops == 1) {
+	_cairo_color_init_rgba (color,
+				gradient->stops[0].color.red,
+				gradient->stops[0].color.green,
+				gradient->stops[0].color.blue,
+				gradient->stops[0].color.alpha);
+	return;
+    }
+
+    end = gradient->n_stops - 1;
+
+    switch (gradient->base.extend) {
+    case CAIRO_EXTEND_REPEAT:
+      /*
+       * Sa, Sb and Sy, Sz are the first two and last two stops respectively.
+       * The weight of the first and last stop can be computed as the area of
+       * the following triangles (taken with height 1, since the whole [0-1]
+       * will have total weight 1 this way): b*h/2
+       *
+       *              +                   +
+       *            / |\                / | \
+       *          /   | \             /   |   \
+       *        /     |  \          /     |     \
+       * ~~~~~+---+---+---+~~~~~~~+-------+---+---+~~~~~
+       *   -1+Sz  0  Sa   Sb      Sy     Sz   1  1+Sa
+       *
+       * For the first stop: (Sb-(-1+Sz)/2 = (1+Sb-Sz)/2
+       * For the last stop: ((1+Sa)-Sy)/2 = (1+Sa-Sy)/2
+       * Halving the result is done after summing up all the areas.
+       */
+	delta0 = 1.0 + gradient->stops[1].offset - gradient->stops[end].offset;
+	delta1 = 1.0 + gradient->stops[0].offset - gradient->stops[end-1].offset;
+	break;
+
+    case CAIRO_EXTEND_REFLECT:
+      /*
+       * Sa, Sb and Sy, Sz are the first two and last two stops respectively.
+       * The weight of the first and last stop can be computed as the area of
+       * the following trapezoids (taken with height 1, since the whole [0-1]
+       * will have total weight 1 this way): (b+B)*h/2
+       *
+       * +-------+                   +---+
+       * |       |\                / |   |
+       * |       | \             /   |   |
+       * |       |  \          /     |   |
+       * +-------+---+~~~~~~~+-------+---+
+       * 0      Sa   Sb      Sy     Sz   1
+       *
+       * For the first stop: (Sa+Sb)/2
+       * For the last stop: ((1-Sz) + (1-Sy))/2 = (2-Sy-Sz)/2
+       * Halving the result is done after summing up all the areas.
+       */
+	delta0 = gradient->stops[0].offset + gradient->stops[1].offset;
+	delta1 = 2.0 - gradient->stops[end-1].offset - gradient->stops[end].offset;
+	break;
+
+    case CAIRO_EXTEND_PAD:
+      /* PAD is computed as the average of the first and last stop:
+       *  - take both of them with weight 1 (they will be halved
+       *    after the whole sum has been computed).
+       *  - avoid summing any of the inner stops.
+       */
+	delta0 = delta1 = 1.0;
+	start = end;
+	break;
+
+    case CAIRO_EXTEND_NONE:
+    default:
+	ASSERT_NOT_REACHED;
+	_cairo_color_init_rgba (color, 0, 0, 0, 0);
+	return;
+    }
+
+    r = delta0 * gradient->stops[0].color.red;
+    g = delta0 * gradient->stops[0].color.green;
+    b = delta0 * gradient->stops[0].color.blue;
+    a = delta0 * gradient->stops[0].color.alpha;
+
+    for (i = start; i < end; ++i) {
+      /* Inner stops weight is the same as the area of the triangle they influence
+       * (which goes from the stop before to the stop after), again with height 1
+       * since the whole must sum up to 1: b*h/2
+       * Halving is done after the whole sum has been computed.
+       */
+	double delta = gradient->stops[i+1].offset - gradient->stops[i-1].offset;
+	r += delta * gradient->stops[i].color.red;
+	g += delta * gradient->stops[i].color.green;
+	b += delta * gradient->stops[i].color.blue;
+	a += delta * gradient->stops[i].color.alpha;
+    }
+
+    r += delta1 * gradient->stops[end].color.red;
+    g += delta1 * gradient->stops[end].color.green;
+    b += delta1 * gradient->stops[end].color.blue;
+    a += delta1 * gradient->stops[end].color.alpha;
+
+    _cairo_color_init_rgba (color, r * .5, g * .5, b * .5, a * .5);
+}
+
+/**
+ * _cairo_pattern_alpha_range:
+ *
+ * Convenience function to determine the minimum and maximum alpha in
+ * the drawn part of a pattern (i.e. ignoring clear parts caused by
+ * extend modes and/or pattern shape).
+ *
+ * If not NULL, out_min and out_max will be set respectively to the
+ * minimum and maximum alpha value of the pattern.
+ **/
+void
+_cairo_pattern_alpha_range (const cairo_pattern_t *pattern,
+			    double                *out_min,
+			    double                *out_max)
+{
+    double alpha_min, alpha_max;
+
+    switch (pattern->type) {
+    case CAIRO_PATTERN_TYPE_SOLID: {
+	const cairo_solid_pattern_t *solid = (cairo_solid_pattern_t *) pattern;
+	alpha_min = alpha_max = solid->color.alpha;
+	break;
+    }
+
+    case CAIRO_PATTERN_TYPE_LINEAR:
+    case CAIRO_PATTERN_TYPE_RADIAL: {
+	const cairo_gradient_pattern_t *gradient = (cairo_gradient_pattern_t *) pattern;
+	unsigned int i;
+
+	assert (gradient->n_stops >= 1);
+
+	alpha_min = alpha_max = gradient->stops[0].color.alpha;
+	for (i = 1; i < gradient->n_stops; i++) {
+	    if (alpha_min > gradient->stops[i].color.alpha)
+		alpha_min = gradient->stops[i].color.alpha;
+	    else if (alpha_max < gradient->stops[i].color.alpha)
+		alpha_max = gradient->stops[i].color.alpha;
+	}
+
+	break;
+    }
+
+    case CAIRO_PATTERN_TYPE_MESH: {
+	const cairo_mesh_pattern_t *mesh = (const cairo_mesh_pattern_t *) pattern;
+	const cairo_mesh_patch_t *patch = _cairo_array_index_const (&mesh->patches, 0);
+	unsigned int i, j, n = _cairo_array_num_elements (&mesh->patches);
+
+	assert (n >= 1);
+
+	alpha_min = alpha_max = patch[0].colors[0].alpha;
+	for (i = 0; i < n; i++) {
+	    for (j = 0; j < 4; j++) {
+		if (patch[i].colors[j].alpha < alpha_min)
+		    alpha_min = patch[i].colors[j].alpha;
+		else if (patch[i].colors[j].alpha > alpha_max)
+		    alpha_max = patch[i].colors[j].alpha;
+	    }
+	}
+
+	break;
+    }
+
+    default:
+	ASSERT_NOT_REACHED;
+	/* fall through */
+
+    case CAIRO_PATTERN_TYPE_SURFACE:
+    case CAIRO_PATTERN_TYPE_RASTER_SOURCE:
+	alpha_min = 0;
+	alpha_max = 1;
+	break;
+    }
+
+    if (out_min)
+	*out_min = alpha_min;
+    if (out_max)
+	*out_max = alpha_max;
+}
+
+/**
+ * _cairo_mesh_pattern_coord_box:
+ *
+ * Convenience function to determine the range of the coordinates of
+ * the points used to define the patches of the mesh.
+ *
+ * This is guaranteed to contain the pattern extents, but might not be
+ * tight, just like a Bezier curve is always inside the convex hull of
+ * the control points.
+ *
+ * This function cannot be used while the mesh is being constructed.
+ *
+ * The function returns TRUE and sets the output parametes to define
+ * the coodrinate range if the mesh pattern contains at least one
+ * patch, otherwise it returns FALSE.
+ **/
+cairo_bool_t
+_cairo_mesh_pattern_coord_box (const cairo_mesh_pattern_t *mesh,
+			       double                     *out_xmin,
+			       double                     *out_ymin,
+			       double                     *out_xmax,
+			       double                     *out_ymax)
+{
+    const cairo_mesh_patch_t *patch;
+    unsigned int num_patches, i, j, k;
+    double x0, y0, x1, y1;
+
+    assert (mesh->current_patch == NULL);
+
+    num_patches = _cairo_array_num_elements (&mesh->patches);
+
+    if (num_patches == 0)
+	return FALSE;
+
+    patch = _cairo_array_index_const (&mesh->patches, 0);
+    x0 = x1 = patch->points[0][0].x;
+    y0 = y1 = patch->points[0][0].y;
+
+    for (i = 0; i < num_patches; i++) {
+	for (j = 0; j < 4; j++) {
+	    for (k = 0; k < 4; k++) {
+		x0 = MIN (x0, patch[i].points[j][k].x);
+		y0 = MIN (y0, patch[i].points[j][k].y);
+		x1 = MAX (x1, patch[i].points[j][k].x);
+		y1 = MAX (y1, patch[i].points[j][k].y);
+	    }
+	}
+    }
+
+    *out_xmin = x0;
+    *out_ymin = y0;
+    *out_xmax = x1;
+    *out_ymax = y1;
+
+    return TRUE;
+}
+
+/**
+ * _cairo_gradient_pattern_is_solid:
+ *
+ * Convenience function to determine whether a gradient pattern is
+ * a solid color within the given extents. In this case the color
+ * argument is initialized to the color the pattern represents.
+ * This functions doesn't handle completely transparent gradients,
+ * thus it should be called only after _cairo_pattern_is_clear has
+ * returned FALSE.
+ *
+ * Return value: %TRUE if the pattern is a solid color.
+ **/
+cairo_bool_t
+_cairo_gradient_pattern_is_solid (const cairo_gradient_pattern_t *gradient,
+				  const cairo_rectangle_int_t *extents,
+				  cairo_color_t *color)
+{
+    unsigned int i;
+
+    assert (gradient->base.type == CAIRO_PATTERN_TYPE_LINEAR ||
+	    gradient->base.type == CAIRO_PATTERN_TYPE_RADIAL);
+
+    /* TODO: radial */
+    if (gradient->base.type == CAIRO_PATTERN_TYPE_LINEAR) {
+	cairo_linear_pattern_t *linear = (cairo_linear_pattern_t *) gradient;
+	if (_linear_pattern_is_degenerate (linear)) {
+	    _gradient_color_average (gradient, color);
+	    return TRUE;
+	}
+
+	if (gradient->base.extend == CAIRO_EXTEND_NONE) {
+	    double t[2];
+
+	    /* We already know that the pattern is not clear, thus if some
+	     * part of it is clear, the whole is not solid.
+	     */
+
+	    if (extents == NULL)
+		return FALSE;
+
+	    _cairo_linear_pattern_box_to_parameter (linear,
+						    extents->x,
+						    extents->y,
+						    extents->x + extents->width,
+						    extents->y + extents->height,
+						    t);
+
+	    if (t[0] < 0.0 || t[1] > 1.0)
+		return FALSE;
+	}
+    } else
+	return FALSE;
+
+    for (i = 1; i < gradient->n_stops; i++)
+	if (! _cairo_color_stop_equal (&gradient->stops[0].color,
+				       &gradient->stops[i].color))
+	    return FALSE;
+
+    _cairo_color_init_rgba (color,
+			    gradient->stops[0].color.red,
+			    gradient->stops[0].color.green,
+			    gradient->stops[0].color.blue,
+			    gradient->stops[0].color.alpha);
+
+    return TRUE;
+}
+
+static cairo_bool_t
+_mesh_is_clear (const cairo_mesh_pattern_t *mesh)
+{
+    double x1, y1, x2, y2;
+    cairo_bool_t is_valid;
+
+    is_valid = _cairo_mesh_pattern_coord_box (mesh, &x1, &y1, &x2, &y2);
+    if (!is_valid)
+	return TRUE;
+
+    if (x2 - x1 < DBL_EPSILON || y2 - y1 < DBL_EPSILON)
+	return TRUE;
+
+    return FALSE;
+}
+
+/**
+ * _cairo_pattern_is_opaque_solid:
+ *
+ * Convenience function to determine whether a pattern is an opaque
+ * (alpha==1.0) solid color pattern. This is done by testing whether
+ * the pattern's alpha value when converted to a byte is 255, so if a
+ * backend actually supported deep alpha channels this function might
+ * not do the right thing.
+ *
+ * Return value: %TRUE if the pattern is an opaque, solid color.
+ **/
+cairo_bool_t
+_cairo_pattern_is_opaque_solid (const cairo_pattern_t *pattern)
+{
+    cairo_solid_pattern_t *solid;
+
+    if (pattern->type != CAIRO_PATTERN_TYPE_SOLID)
+	return FALSE;
+
+    solid = (cairo_solid_pattern_t *) pattern;
+
+    return CAIRO_COLOR_IS_OPAQUE (&solid->color);
+}
+
+static cairo_bool_t
+_surface_is_opaque (const cairo_surface_pattern_t *pattern,
+		    const cairo_rectangle_int_t *sample)
+{
+    cairo_rectangle_int_t extents;
+
+    if (pattern->surface->content & CAIRO_CONTENT_ALPHA)
+	return FALSE;
+
+    if (pattern->base.extend != CAIRO_EXTEND_NONE)
+	return TRUE;
+
+    if (! _cairo_surface_get_extents (pattern->surface, &extents))
+	return TRUE;
+
+    if (sample == NULL)
+	return FALSE;
+
+    return _cairo_rectangle_contains_rectangle (&extents, sample);
+}
+
+static cairo_bool_t
+_raster_source_is_opaque (const cairo_raster_source_pattern_t *pattern,
+			  const cairo_rectangle_int_t *sample)
+{
+    if (pattern->content & CAIRO_CONTENT_ALPHA)
+	return FALSE;
+
+    if (pattern->base.extend != CAIRO_EXTEND_NONE)
+	return TRUE;
+
+    if (sample == NULL)
+	return FALSE;
+
+    return _cairo_rectangle_contains_rectangle (&pattern->extents, sample);
+}
+
+static cairo_bool_t
+_surface_is_clear (const cairo_surface_pattern_t *pattern)
+{
+    cairo_rectangle_int_t extents;
+
+    if (_cairo_surface_get_extents (pattern->surface, &extents) &&
+	(extents.width == 0 || extents.height == 0))
+	return TRUE;
+
+    return pattern->surface->is_clear &&
+	pattern->surface->content & CAIRO_CONTENT_ALPHA;
+}
+
+static cairo_bool_t
+_raster_source_is_clear (const cairo_raster_source_pattern_t *pattern)
+{
+    return pattern->extents.width == 0 || pattern->extents.height == 0;
+}
+
+static cairo_bool_t
+_gradient_is_opaque (const cairo_gradient_pattern_t *gradient,
+		     const cairo_rectangle_int_t *sample)
+{
+    unsigned int i;
+
+    assert (gradient->base.type == CAIRO_PATTERN_TYPE_LINEAR ||
+	    gradient->base.type == CAIRO_PATTERN_TYPE_RADIAL);
+
+    if (gradient->n_stops == 0 ||
+	(gradient->base.extend == CAIRO_EXTEND_NONE &&
+	 gradient->stops[0].offset == gradient->stops[gradient->n_stops - 1].offset))
+	return FALSE;
+
+    if (gradient->base.type == CAIRO_PATTERN_TYPE_LINEAR) {
+	if (gradient->base.extend == CAIRO_EXTEND_NONE) {
+	    double t[2];
+	    cairo_linear_pattern_t *linear = (cairo_linear_pattern_t *) gradient;
+
+	    /* EXTEND_NONE degenerate radial gradients are clear */
+	    if (_linear_pattern_is_degenerate (linear))
+		return FALSE;
+
+	    if (sample == NULL)
+		return FALSE;
+
+	    _cairo_linear_pattern_box_to_parameter (linear,
+						    sample->x,
+						    sample->y,
+						    sample->x + sample->width,
+						    sample->y + sample->height,
+						    t);
+
+	    if (t[0] < 0.0 || t[1] > 1.0)
+		return FALSE;
+	}
+    } else
+	return FALSE; /* TODO: check actual intersection */
+
+    for (i = 0; i < gradient->n_stops; i++)
+	if (! CAIRO_COLOR_IS_OPAQUE (&gradient->stops[i].color))
+	    return FALSE;
+
+    return TRUE;
+}
+
+/**
+ * _cairo_pattern_is_opaque:
+ *
+ * Convenience function to determine whether a pattern is an opaque
+ * pattern (of any type). The same caveats that apply to
+ * _cairo_pattern_is_opaque_solid apply here as well.
+ *
+ * Return value: %TRUE if the pattern is a opaque.
+ **/
+cairo_bool_t
+_cairo_pattern_is_opaque (const cairo_pattern_t *abstract_pattern,
+			  const cairo_rectangle_int_t *sample)
+{
+    const cairo_pattern_union_t *pattern;
+
+    if (abstract_pattern->has_component_alpha)
+	return FALSE;
+
+    pattern = (cairo_pattern_union_t *) abstract_pattern;
+    switch (pattern->base.type) {
+    case CAIRO_PATTERN_TYPE_SOLID:
+	return _cairo_pattern_is_opaque_solid (abstract_pattern);
+    case CAIRO_PATTERN_TYPE_SURFACE:
+	return _surface_is_opaque (&pattern->surface, sample);
+    case CAIRO_PATTERN_TYPE_RASTER_SOURCE:
+	return _raster_source_is_opaque (&pattern->raster_source, sample);
+    case CAIRO_PATTERN_TYPE_LINEAR:
+    case CAIRO_PATTERN_TYPE_RADIAL:
+	return _gradient_is_opaque (&pattern->gradient.base, sample);
+    case CAIRO_PATTERN_TYPE_MESH:
+	return FALSE;
+    }
+
+    ASSERT_NOT_REACHED;
+    return FALSE;
+}
+
+cairo_bool_t
+_cairo_pattern_is_clear (const cairo_pattern_t *abstract_pattern)
+{
+    const cairo_pattern_union_t *pattern;
+
+    if (abstract_pattern->has_component_alpha)
+	return FALSE;
+
+    pattern = (cairo_pattern_union_t *) abstract_pattern;
+    switch (abstract_pattern->type) {
+    case CAIRO_PATTERN_TYPE_SOLID:
+	return CAIRO_COLOR_IS_CLEAR (&pattern->solid.color);
+    case CAIRO_PATTERN_TYPE_SURFACE:
+	return _surface_is_clear (&pattern->surface);
+    case CAIRO_PATTERN_TYPE_RASTER_SOURCE:
+	return _raster_source_is_clear (&pattern->raster_source);
+    case CAIRO_PATTERN_TYPE_LINEAR:
+    case CAIRO_PATTERN_TYPE_RADIAL:
+	return _gradient_is_clear (&pattern->gradient.base, NULL);
+    case CAIRO_PATTERN_TYPE_MESH:
+	return _mesh_is_clear (&pattern->mesh);
+    }
+
+    ASSERT_NOT_REACHED;
+    return FALSE;
+}
+
+/**
+ * _cairo_pattern_analyze_filter:
+ * @pattern: surface pattern
+ * @pad_out: location to store necessary padding in the source image, or %NULL
+ * Returns: the optimized #cairo_filter_t to use with @pattern.
+ *
+ * Analyze the filter to determine how much extra needs to be sampled
+ * from the source image to account for the filter radius and whether
+ * we can optimize the filter to a simpler value.
+ *
+ * XXX: We don't actually have any way of querying the backend for
+ *      the filter radius, so we just guess base on what we know that
+ *      backends do currently (see bug #10508)
+ **/
+cairo_filter_t
+_cairo_pattern_analyze_filter (const cairo_pattern_t	*pattern,
+			       double			*pad_out)
+{
+    double pad;
+    cairo_filter_t optimized_filter;
+
+    switch (pattern->filter) {
+    case CAIRO_FILTER_GOOD:
+    case CAIRO_FILTER_BEST:
+    case CAIRO_FILTER_BILINEAR:
+	/* If source pixels map 1:1 onto destination pixels, we do
+	 * not need to filter (and do not want to filter, since it
+	 * will cause blurriness)
+	 */
+	if (_cairo_matrix_is_pixel_exact (&pattern->matrix)) {
+	    pad = 0.;
+	    optimized_filter = CAIRO_FILTER_NEAREST;
+	} else {
+	    /* 0.5 is enough for a bilinear filter. It's possible we
+	     * should defensively use more for CAIRO_FILTER_BEST, but
+	     * without a single example, it's hard to know how much
+	     * more would be defensive...
+	     */
+	    pad = 0.5;
+	    optimized_filter = pattern->filter;
+	}
+	break;
+
+    case CAIRO_FILTER_FAST:
+    case CAIRO_FILTER_NEAREST:
+    case CAIRO_FILTER_GAUSSIAN:
+    default:
+	pad = 0.;
+	optimized_filter = pattern->filter;
+	break;
+    }
+
+    if (pad_out)
+	*pad_out = pad;
+
+    return optimized_filter;
+}
+
+cairo_filter_t
+_cairo_pattern_sampled_area (const cairo_pattern_t *pattern,
+			     const cairo_rectangle_int_t *extents,
+			     cairo_rectangle_int_t *sample)
+{
+    cairo_filter_t filter;
+    double x1, x2, y1, y2;
+    double pad;
+
+    filter = _cairo_pattern_analyze_filter (pattern, &pad);
+    if (pad == 0.0 && _cairo_matrix_is_identity (&pattern->matrix)) {
+	*sample = *extents;
+	return filter;
+    }
+
+    x1 = extents->x;
+    y1 = extents->y;
+    x2 = extents->x + (int) extents->width;
+    y2 = extents->y + (int) extents->height;
+
+    _cairo_matrix_transform_bounding_box (&pattern->matrix,
+					  &x1, &y1, &x2, &y2,
+					  NULL);
+    if (x1 > CAIRO_RECT_INT_MIN)
+	sample->x = floor (x1 - pad);
+    else
+	sample->x = CAIRO_RECT_INT_MIN;
+
+    if (y1 > CAIRO_RECT_INT_MIN)
+	sample->y = floor (y1 - pad);
+    else
+	sample->y = CAIRO_RECT_INT_MIN;
+
+    if (x2 < CAIRO_RECT_INT_MAX)
+	sample->width = ceil (x2 + pad);
+    else
+	sample->width = CAIRO_RECT_INT_MAX;
+
+    if (y2 < CAIRO_RECT_INT_MAX)
+	sample->height = ceil (y2 + pad);
+    else
+	sample->height = CAIRO_RECT_INT_MAX;
+
+    sample->width  -= sample->x;
+    sample->height -= sample->y;
+
+    return filter;
+}
+
+/**
+ * _cairo_pattern_get_extents:
+ *
+ * Return the "target-space" extents of @pattern in @extents.
+ *
+ * For unbounded patterns, the @extents will be initialized with
+ * "infinite" extents, (minimum and maximum fixed-point values).
+ *
+ * XXX: Currently, bounded gradient patterns will also return
+ * "infinite" extents, though it would be possible to optimize these
+ * with a little more work.
+ **/
+void
+_cairo_pattern_get_extents (const cairo_pattern_t         *pattern,
+			    cairo_rectangle_int_t         *extents)
+{
+    double x1, y1, x2, y2;
+    cairo_status_t status;
+
+    switch (pattern->type) {
+    case CAIRO_PATTERN_TYPE_SOLID:
+	goto UNBOUNDED;
+
+    case CAIRO_PATTERN_TYPE_SURFACE:
+	{
+	    cairo_rectangle_int_t surface_extents;
+	    const cairo_surface_pattern_t *surface_pattern =
+		(const cairo_surface_pattern_t *) pattern;
+	    cairo_surface_t *surface = surface_pattern->surface;
+	    double pad;
+
+	    if (! _cairo_surface_get_extents (surface, &surface_extents))
+		goto UNBOUNDED;
+
+	    if (surface_extents.width == 0 || surface_extents.height == 0)
+		goto EMPTY;
+
+	    if (pattern->extend != CAIRO_EXTEND_NONE)
+		goto UNBOUNDED;
+
+	    /* The filter can effectively enlarge the extents of the
+	     * pattern, so extend as necessary.
+	     */
+	    _cairo_pattern_analyze_filter (&surface_pattern->base, &pad);
+	    x1 = surface_extents.x - pad;
+	    y1 = surface_extents.y - pad;
+	    x2 = surface_extents.x + (int) surface_extents.width  + pad;
+	    y2 = surface_extents.y + (int) surface_extents.height + pad;
+	}
+	break;
+
+    case CAIRO_PATTERN_TYPE_RASTER_SOURCE:
+	{
+	    const cairo_raster_source_pattern_t *raster =
+		(const cairo_raster_source_pattern_t *) pattern;
+	    double pad;
+
+	    if (raster->extents.width == 0 || raster->extents.height == 0)
+		goto EMPTY;
+
+	    if (pattern->extend != CAIRO_EXTEND_NONE)
+		goto UNBOUNDED;
+
+	    /* The filter can effectively enlarge the extents of the
+	     * pattern, so extend as necessary.
+	     */
+	    _cairo_pattern_analyze_filter (pattern, &pad);
+	    x1 = raster->extents.x - pad;
+	    y1 = raster->extents.y - pad;
+	    x2 = raster->extents.x + (int) raster->extents.width  + pad;
+	    y2 = raster->extents.y + (int) raster->extents.height + pad;
+	}
+	break;
+
+    case CAIRO_PATTERN_TYPE_RADIAL:
+	{
+	    const cairo_radial_pattern_t *radial =
+		(const cairo_radial_pattern_t *) pattern;
+	    double cx1, cy1;
+	    double cx2, cy2;
+	    double r1, r2;
+
+	    if (_radial_pattern_is_degenerate (radial)) {
+		/* cairo-gstate should have optimised degenerate
+		 * patterns to solid clear patterns, so we can ignore
+		 * them here. */
+		goto EMPTY;
+	    }
+
+	    /* TODO: in some cases (focus outside/on the circle) it is
+	     * half-bounded. */
+	    if (pattern->extend != CAIRO_EXTEND_NONE)
+		goto UNBOUNDED;
+
+	    cx1 = radial->cd1.center.x;
+	    cy1 = radial->cd1.center.y;
+	    r1  = radial->cd1.radius;
+
+	    cx2 = radial->cd2.center.x;
+	    cy2 = radial->cd2.center.y;
+	    r2  = radial->cd2.radius;
+
+	    x1 = MIN (cx1 - r1, cx2 - r2);
+	    y1 = MIN (cy1 - r1, cy2 - r2);
+	    x2 = MAX (cx1 + r1, cx2 + r2);
+	    y2 = MAX (cy1 + r1, cy2 + r2);
+	}
+	break;
+
+    case CAIRO_PATTERN_TYPE_LINEAR:
+	{
+	    const cairo_linear_pattern_t *linear =
+		(const cairo_linear_pattern_t *) pattern;
+
+	    if (pattern->extend != CAIRO_EXTEND_NONE)
+		goto UNBOUNDED;
+
+	    if (_linear_pattern_is_degenerate (linear)) {
+		/* cairo-gstate should have optimised degenerate
+		 * patterns to solid ones, so we can again ignore
+		 * them here. */
+		goto EMPTY;
+	    }
+
+	    /* TODO: to get tight extents, use the matrix to transform
+	     * the pattern instead of transforming the extents later. */
+	    if (pattern->matrix.xy != 0. || pattern->matrix.yx != 0.)
+		goto UNBOUNDED;
+
+	    if (linear->pd1.x == linear->pd2.x) {
+		x1 = -HUGE_VAL;
+		x2 = HUGE_VAL;
+		y1 = MIN (linear->pd1.y, linear->pd2.y);
+		y2 = MAX (linear->pd1.y, linear->pd2.y);
+	    } else if (linear->pd1.y == linear->pd2.y) {
+		x1 = MIN (linear->pd1.x, linear->pd2.x);
+		x2 = MAX (linear->pd1.x, linear->pd2.x);
+		y1 = -HUGE_VAL;
+		y2 = HUGE_VAL;
+	    } else {
+		goto  UNBOUNDED;
+	    }
+	}
+	break;
+
+    case CAIRO_PATTERN_TYPE_MESH:
+	{
+	    const cairo_mesh_pattern_t *mesh =
+		(const cairo_mesh_pattern_t *) pattern;
+	    double padx, pady;
+	    cairo_bool_t is_valid;
+
+	    is_valid = _cairo_mesh_pattern_coord_box (mesh, &x1, &y1, &x2, &y2);
+	    if (!is_valid)
+		goto EMPTY;
+
+	    padx = pady = 1.;
+	    cairo_matrix_transform_distance (&pattern->matrix, &padx, &pady);
+	    padx = fabs (padx);
+	    pady = fabs (pady);
+
+	    x1 -= padx;
+	    y1 -= pady;
+	    x2 += padx;
+	    y2 += pady;
+	}
+	break;
+
+    default:
+	ASSERT_NOT_REACHED;
+    }
+
+    if (_cairo_matrix_is_translation (&pattern->matrix)) {
+	x1 -= pattern->matrix.x0; x2 -= pattern->matrix.x0;
+	y1 -= pattern->matrix.y0; y2 -= pattern->matrix.y0;
+    } else {
+	cairo_matrix_t imatrix;
+
+	imatrix = pattern->matrix;
+	status = cairo_matrix_invert (&imatrix);
+	/* cairo_pattern_set_matrix ensures the matrix is invertible */
+	assert (status == CAIRO_STATUS_SUCCESS);
+
+	_cairo_matrix_transform_bounding_box (&imatrix,
+					      &x1, &y1, &x2, &y2,
+					      NULL);
+    }
+
+    x1 = floor (x1);
+    if (x1 < CAIRO_RECT_INT_MIN)
+	x1 = CAIRO_RECT_INT_MIN;
+    y1 = floor (y1);
+    if (y1 < CAIRO_RECT_INT_MIN)
+	y1 = CAIRO_RECT_INT_MIN;
+
+    x2 = ceil (x2);
+    if (x2 > CAIRO_RECT_INT_MAX)
+	x2 = CAIRO_RECT_INT_MAX;
+    y2 = ceil (y2);
+    if (y2 > CAIRO_RECT_INT_MAX)
+	y2 = CAIRO_RECT_INT_MAX;
+
+    extents->x = x1; extents->width  = x2 - x1;
+    extents->y = y1; extents->height = y2 - y1;
+    return;
+
+  UNBOUNDED:
+    /* unbounded patterns -> 'infinite' extents */
+    _cairo_unbounded_rectangle_init (extents);
+    return;
+
+  EMPTY:
+    extents->x = extents->y = 0;
+    extents->width = extents->height = 0;
+    return;
+}
+
+void
+_cairo_pattern_get_exact_extents (const cairo_pattern_t         *pattern,
+				  cairo_rectangle_t             *extents)
+{
+    double x1, y1, x2, y2;
+    cairo_status_t status;
+    cairo_rectangle_int_t int_rect;;
+
+    switch (pattern->type) {
+    case CAIRO_PATTERN_TYPE_SOLID:
+	goto UNBOUNDED;
+
+    case CAIRO_PATTERN_TYPE_SURFACE:
+	{
+	    cairo_rectangle_int_t surface_extents;
+	    const cairo_surface_pattern_t *surface_pattern =
+		(const cairo_surface_pattern_t *) pattern;
+	    cairo_surface_t *surface = surface_pattern->surface;
+
+	    if (! _cairo_surface_get_extents (surface, &surface_extents))
+		goto UNBOUNDED;
+
+	    if (surface_extents.width == 0 || surface_extents.height == 0)
+		goto EMPTY;
+
+	    if (pattern->extend != CAIRO_EXTEND_NONE)
+		goto UNBOUNDED;
+
+	    x1 = surface_extents.x;
+	    y1 = surface_extents.y;
+	    x2 = surface_extents.x + surface_extents.width;
+	    y2 = surface_extents.y + surface_extents.height;
+	}
+	break;
+
+    case CAIRO_PATTERN_TYPE_RASTER_SOURCE:
+	{
+	    const cairo_raster_source_pattern_t *raster =
+		(const cairo_raster_source_pattern_t *) pattern;
+
+	    if (raster->extents.width == 0 || raster->extents.height == 0)
+		goto EMPTY;
+
+	    if (pattern->extend != CAIRO_EXTEND_NONE)
+		goto UNBOUNDED;
+
+	    x1 = raster->extents.x;
+	    y1 = raster->extents.y;
+	    x2 = raster->extents.x + raster->extents.width;
+	    y2 = raster->extents.y + raster->extents.height;
+	}
+	break;
+
+    case CAIRO_PATTERN_TYPE_RADIAL:
+	{
+	    const cairo_radial_pattern_t *radial =
+		(const cairo_radial_pattern_t *) pattern;
+	    double cx1, cy1;
+	    double cx2, cy2;
+	    double r1, r2;
+
+	    if (_radial_pattern_is_degenerate (radial)) {
+		/* cairo-gstate should have optimised degenerate
+		 * patterns to solid clear patterns, so we can ignore
+		 * them here. */
+		goto EMPTY;
+	    }
+
+	    /* TODO: in some cases (focus outside/on the circle) it is
+	     * half-bounded. */
+	    if (pattern->extend != CAIRO_EXTEND_NONE)
+		goto UNBOUNDED;
+
+	    cx1 = radial->cd1.center.x;
+	    cy1 = radial->cd1.center.y;
+	    r1  = radial->cd1.radius;
+
+	    cx2 = radial->cd2.center.x;
+	    cy2 = radial->cd2.center.y;
+	    r2  = radial->cd2.radius;
+
+	    x1 = MIN (cx1 - r1, cx2 - r2);
+	    y1 = MIN (cy1 - r1, cy2 - r2);
+	    x2 = MAX (cx1 + r1, cx2 + r2);
+	    y2 = MAX (cy1 + r1, cy2 + r2);
+	}
+	break;
+
+    case CAIRO_PATTERN_TYPE_LINEAR:
+	{
+	    const cairo_linear_pattern_t *linear =
+		(const cairo_linear_pattern_t *) pattern;
+
+	    if (pattern->extend != CAIRO_EXTEND_NONE)
+		goto UNBOUNDED;
+
+	    if (_linear_pattern_is_degenerate (linear)) {
+		/* cairo-gstate should have optimised degenerate
+		 * patterns to solid ones, so we can again ignore
+		 * them here. */
+		goto EMPTY;
+	    }
+
+	    /* TODO: to get tight extents, use the matrix to transform
+	     * the pattern instead of transforming the extents later. */
+	    if (pattern->matrix.xy != 0. || pattern->matrix.yx != 0.)
+		goto UNBOUNDED;
+
+	    if (linear->pd1.x == linear->pd2.x) {
+		x1 = -HUGE_VAL;
+		x2 = HUGE_VAL;
+		y1 = MIN (linear->pd1.y, linear->pd2.y);
+		y2 = MAX (linear->pd1.y, linear->pd2.y);
+	    } else if (linear->pd1.y == linear->pd2.y) {
+		x1 = MIN (linear->pd1.x, linear->pd2.x);
+		x2 = MAX (linear->pd1.x, linear->pd2.x);
+		y1 = -HUGE_VAL;
+		y2 = HUGE_VAL;
+	    } else {
+		goto  UNBOUNDED;
+	    }
+	}
+	break;
+
+    case CAIRO_PATTERN_TYPE_MESH:
+	{
+	    const cairo_mesh_pattern_t *mesh =
+		(const cairo_mesh_pattern_t *) pattern;
+	    double padx, pady;
+	    cairo_bool_t is_valid;
+
+	    is_valid = _cairo_mesh_pattern_coord_box (mesh, &x1, &y1, &x2, &y2);
+	    if (!is_valid)
+		goto EMPTY;
+
+	    padx = pady = 1.;
+	    cairo_matrix_transform_distance (&pattern->matrix, &padx, &pady);
+	    padx = fabs (padx);
+	    pady = fabs (pady);
+
+	    x1 -= padx;
+	    y1 -= pady;
+	    x2 += padx;
+	    y2 += pady;
+	}
+	break;
+
+    default:
+	ASSERT_NOT_REACHED;
+    }
+
+    if (_cairo_matrix_is_translation (&pattern->matrix)) {
+	x1 -= pattern->matrix.x0; x2 -= pattern->matrix.x0;
+	y1 -= pattern->matrix.y0; y2 -= pattern->matrix.y0;
+    } else {
+	cairo_matrix_t imatrix;
+
+	imatrix = pattern->matrix;
+	status = cairo_matrix_invert (&imatrix);
+	/* cairo_pattern_set_matrix ensures the matrix is invertible */
+	assert (status == CAIRO_STATUS_SUCCESS);
+
+	_cairo_matrix_transform_bounding_box (&imatrix,
+					      &x1, &y1, &x2, &y2,
+					      NULL);
+    }
+
+    if (x1 < CAIRO_RECT_INT_MIN)
+	x1 = CAIRO_RECT_INT_MIN;
+    if (y1 < CAIRO_RECT_INT_MIN)
+	y1 = CAIRO_RECT_INT_MIN;
+
+    if (x2 > CAIRO_RECT_INT_MAX)
+	x2 = CAIRO_RECT_INT_MAX;
+    if (y2 > CAIRO_RECT_INT_MAX)
+	y2 = CAIRO_RECT_INT_MAX;
+
+    extents->x = x1; extents->width  = x2 - x1;
+    extents->y = y1; extents->height = y2 - y1;
+    return;
+
+  UNBOUNDED:
+    /* unbounded patterns -> 'infinite' extents */
+    _cairo_unbounded_rectangle_init (&int_rect);
+    extents->x = int_rect.x;
+    extents->y = int_rect.y;
+    extents->width = int_rect.width;
+    extents->height = int_rect.height;
+    return;
+
+  EMPTY:
+    extents->x = extents->y = 0;
+    extents->width = extents->height = 0;
+    return;
+}
+
+/**
+ * _cairo_pattern_get_ink_extents:
+ *
+ * Return the "target-space" inked extents of @pattern in @extents.
+ **/
+cairo_int_status_t
+_cairo_pattern_get_ink_extents (const cairo_pattern_t         *pattern,
+				cairo_rectangle_int_t         *extents)
+{
+    if (pattern->type == CAIRO_PATTERN_TYPE_SURFACE &&
+	pattern->extend == CAIRO_EXTEND_NONE)
+    {
+	const cairo_surface_pattern_t *surface_pattern =
+	    (const cairo_surface_pattern_t *) pattern;
+	cairo_surface_t *surface = surface_pattern->surface;
+
+	surface = _cairo_surface_get_source (surface, NULL);
+	if (_cairo_surface_is_recording (surface)) {
+	    cairo_matrix_t imatrix;
+	    cairo_box_t box;
+	    cairo_status_t status;
+
+	    imatrix = pattern->matrix;
+	    status = cairo_matrix_invert (&imatrix);
+	    /* cairo_pattern_set_matrix ensures the matrix is invertible */
+	    assert (status == CAIRO_STATUS_SUCCESS);
+
+	    status = _cairo_recording_surface_get_ink_bbox ((cairo_recording_surface_t *)surface,
+						   &box, &imatrix);
+	    if (unlikely (status))
+		return status;
+
+	    _cairo_box_round_to_rectangle (&box, extents);
+	    return CAIRO_STATUS_SUCCESS;
+	}
+    }
+
+    _cairo_pattern_get_extents (pattern, extents);
+    return CAIRO_STATUS_SUCCESS;
+}
+
+static unsigned long
+_cairo_solid_pattern_hash (unsigned long hash,
+			   const cairo_solid_pattern_t *solid)
+{
+    hash = _cairo_hash_bytes (hash, &solid->color, sizeof (solid->color));
+
+    return hash;
+}
+
+static unsigned long
+_cairo_gradient_color_stops_hash (unsigned long hash,
+				  const cairo_gradient_pattern_t *gradient)
+{
+    unsigned int n;
+
+    hash = _cairo_hash_bytes (hash,
+			      &gradient->n_stops,
+			      sizeof (gradient->n_stops));
+
+    for (n = 0; n < gradient->n_stops; n++) {
+	hash = _cairo_hash_bytes (hash,
+				  &gradient->stops[n].offset,
+				  sizeof (double));
+	hash = _cairo_hash_bytes (hash,
+				  &gradient->stops[n].color,
+				  sizeof (cairo_color_stop_t));
+    }
+
+    return hash;
+}
+
+unsigned long
+_cairo_linear_pattern_hash (unsigned long hash,
+			    const cairo_linear_pattern_t *linear)
+{
+    hash = _cairo_hash_bytes (hash, &linear->pd1, sizeof (linear->pd1));
+    hash = _cairo_hash_bytes (hash, &linear->pd2, sizeof (linear->pd2));
+
+    return _cairo_gradient_color_stops_hash (hash, &linear->base);
+}
+
+unsigned long
+_cairo_radial_pattern_hash (unsigned long hash,
+			    const cairo_radial_pattern_t *radial)
+{
+    hash = _cairo_hash_bytes (hash, &radial->cd1.center, sizeof (radial->cd1.center));
+    hash = _cairo_hash_bytes (hash, &radial->cd1.radius, sizeof (radial->cd1.radius));
+    hash = _cairo_hash_bytes (hash, &radial->cd2.center, sizeof (radial->cd2.center));
+    hash = _cairo_hash_bytes (hash, &radial->cd2.radius, sizeof (radial->cd2.radius));
+
+    return _cairo_gradient_color_stops_hash (hash, &radial->base);
+}
+
+static unsigned long
+_cairo_mesh_pattern_hash (unsigned long hash, const cairo_mesh_pattern_t *mesh)
+{
+    const cairo_mesh_patch_t *patch = _cairo_array_index_const (&mesh->patches, 0);
+    unsigned int i, n = _cairo_array_num_elements (&mesh->patches);
+
+    for (i = 0; i < n; i++)
+       hash = _cairo_hash_bytes (hash, patch + i, sizeof (cairo_mesh_patch_t));
+
+    return hash;
+}
+
+static unsigned long
+_cairo_surface_pattern_hash (unsigned long hash,
+			     const cairo_surface_pattern_t *surface)
+{
+    hash ^= surface->surface->unique_id;
+
+    return hash;
+}
+
+static unsigned long
+_cairo_raster_source_pattern_hash (unsigned long hash,
+				   const cairo_raster_source_pattern_t *raster)
+{
+    hash ^= (uintptr_t)raster->user_data;
+
+    return hash;
+}
+
+unsigned long
+_cairo_pattern_hash (const cairo_pattern_t *pattern)
+{
+    unsigned long hash = _CAIRO_HASH_INIT_VALUE;
+
+    if (pattern->status)
+	return 0;
+
+    hash = _cairo_hash_bytes (hash, &pattern->type, sizeof (pattern->type));
+    if (pattern->type != CAIRO_PATTERN_TYPE_SOLID) {
+	hash = _cairo_hash_bytes (hash,
+				  &pattern->matrix, sizeof (pattern->matrix));
+	hash = _cairo_hash_bytes (hash,
+				  &pattern->filter, sizeof (pattern->filter));
+	hash = _cairo_hash_bytes (hash,
+				  &pattern->extend, sizeof (pattern->extend));
+	hash = _cairo_hash_bytes (hash,
+				  &pattern->has_component_alpha,
+				  sizeof (pattern->has_component_alpha));
+    }
+
+    switch (pattern->type) {
+    case CAIRO_PATTERN_TYPE_SOLID:
+	return _cairo_solid_pattern_hash (hash, (cairo_solid_pattern_t *) pattern);
+    case CAIRO_PATTERN_TYPE_LINEAR:
+	return _cairo_linear_pattern_hash (hash, (cairo_linear_pattern_t *) pattern);
+    case CAIRO_PATTERN_TYPE_RADIAL:
+	return _cairo_radial_pattern_hash (hash, (cairo_radial_pattern_t *) pattern);
+    case CAIRO_PATTERN_TYPE_MESH:
+	return _cairo_mesh_pattern_hash (hash, (cairo_mesh_pattern_t *) pattern);
+    case CAIRO_PATTERN_TYPE_SURFACE:
+	return _cairo_surface_pattern_hash (hash, (cairo_surface_pattern_t *) pattern);
+    case CAIRO_PATTERN_TYPE_RASTER_SOURCE:
+	return _cairo_raster_source_pattern_hash (hash, (cairo_raster_source_pattern_t *) pattern);
+    default:
+	ASSERT_NOT_REACHED;
+	return FALSE;
+    }
+}
+
+static cairo_bool_t
+_cairo_solid_pattern_equal (const cairo_solid_pattern_t *a,
+			    const cairo_solid_pattern_t *b)
+{
+    return _cairo_color_equal (&a->color, &b->color);
+}
+
+static cairo_bool_t
+_cairo_gradient_color_stops_equal (const cairo_gradient_pattern_t *a,
+				   const cairo_gradient_pattern_t *b)
+{
+    unsigned int n;
+
+    if (a->n_stops != b->n_stops)
+	return FALSE;
+
+    for (n = 0; n < a->n_stops; n++) {
+	if (a->stops[n].offset != b->stops[n].offset)
+	    return FALSE;
+	if (! _cairo_color_stop_equal (&a->stops[n].color, &b->stops[n].color))
+	    return FALSE;
+    }
+
+    return TRUE;
+}
+
+cairo_bool_t
+_cairo_linear_pattern_equal (const cairo_linear_pattern_t *a,
+			     const cairo_linear_pattern_t *b)
+{
+    if (a->pd1.x != b->pd1.x)
+	return FALSE;
+
+    if (a->pd1.y != b->pd1.y)
+	return FALSE;
+
+    if (a->pd2.x != b->pd2.x)
+	return FALSE;
+
+    if (a->pd2.y != b->pd2.y)
+	return FALSE;
+
+    return _cairo_gradient_color_stops_equal (&a->base, &b->base);
+}
+
+cairo_bool_t
+_cairo_radial_pattern_equal (const cairo_radial_pattern_t *a,
+			     const cairo_radial_pattern_t *b)
+{
+    if (a->cd1.center.x != b->cd1.center.x)
+	return FALSE;
+
+    if (a->cd1.center.y != b->cd1.center.y)
+	return FALSE;
+
+    if (a->cd1.radius != b->cd1.radius)
+	return FALSE;
+
+    if (a->cd2.center.x != b->cd2.center.x)
+	return FALSE;
+
+    if (a->cd2.center.y != b->cd2.center.y)
+	return FALSE;
+
+    if (a->cd2.radius != b->cd2.radius)
+	return FALSE;
+
+    return _cairo_gradient_color_stops_equal (&a->base, &b->base);
+}
+
+static cairo_bool_t
+_cairo_mesh_pattern_equal (const cairo_mesh_pattern_t *a,
+			   const cairo_mesh_pattern_t *b)
+{
+    const cairo_mesh_patch_t *patch_a, *patch_b;
+    unsigned int i, num_patches_a, num_patches_b;
+
+    num_patches_a = _cairo_array_num_elements (&a->patches);
+    num_patches_b = _cairo_array_num_elements (&b->patches);
+
+    if (num_patches_a != num_patches_b)
+	return FALSE;
+
+    for (i = 0; i < num_patches_a; i++) {
+	patch_a = _cairo_array_index_const (&a->patches, i);
+	patch_b = _cairo_array_index_const (&b->patches, i);
+	if (patch_a == NULL || patch_b == NULL)
+	    return FALSE;
+
+	if (memcmp (patch_a, patch_b, sizeof(cairo_mesh_patch_t)) != 0)
+	    return FALSE;
+    }
+
+    return TRUE;
+}
+
+static cairo_bool_t
+_cairo_surface_pattern_equal (const cairo_surface_pattern_t *a,
+			      const cairo_surface_pattern_t *b)
+{
+    return a->surface->unique_id == b->surface->unique_id;
+}
+
+static cairo_bool_t
+_cairo_raster_source_pattern_equal (const cairo_raster_source_pattern_t *a,
+				    const cairo_raster_source_pattern_t *b)
+{
+    return a->user_data == b->user_data;
+}
+
+cairo_bool_t
+_cairo_pattern_equal (const cairo_pattern_t *a, const cairo_pattern_t *b)
+{
+    if (a->status || b->status)
+	return FALSE;
+
+    if (a == b)
+	return TRUE;
+
+    if (a->type != b->type)
+	return FALSE;
+
+    if (a->has_component_alpha != b->has_component_alpha)
+	return FALSE;
+
+    if (a->type != CAIRO_PATTERN_TYPE_SOLID) {
+	if (memcmp (&a->matrix, &b->matrix, sizeof (cairo_matrix_t)))
+	    return FALSE;
+
+	if (a->filter != b->filter)
+	    return FALSE;
+
+	if (a->extend != b->extend)
+	    return FALSE;
+    }
+
+    switch (a->type) {
+    case CAIRO_PATTERN_TYPE_SOLID:
+	return _cairo_solid_pattern_equal ((cairo_solid_pattern_t *) a,
+					   (cairo_solid_pattern_t *) b);
+    case CAIRO_PATTERN_TYPE_LINEAR:
+	return _cairo_linear_pattern_equal ((cairo_linear_pattern_t *) a,
+					    (cairo_linear_pattern_t *) b);
+    case CAIRO_PATTERN_TYPE_RADIAL:
+	return _cairo_radial_pattern_equal ((cairo_radial_pattern_t *) a,
+					    (cairo_radial_pattern_t *) b);
+    case CAIRO_PATTERN_TYPE_MESH:
+	return _cairo_mesh_pattern_equal ((cairo_mesh_pattern_t *) a,
+					  (cairo_mesh_pattern_t *) b);
+    case CAIRO_PATTERN_TYPE_SURFACE:
+	return _cairo_surface_pattern_equal ((cairo_surface_pattern_t *) a,
+					     (cairo_surface_pattern_t *) b);
+    case CAIRO_PATTERN_TYPE_RASTER_SOURCE:
+	return _cairo_raster_source_pattern_equal ((cairo_raster_source_pattern_t *) a,
+						   (cairo_raster_source_pattern_t *) b);
+    default:
+	ASSERT_NOT_REACHED;
+	return FALSE;
+    }
+}
+
+/**
+ * cairo_pattern_get_rgba:
+ * @pattern: a #cairo_pattern_t
+ * @red: return value for red component of color, or %NULL
+ * @green: return value for green component of color, or %NULL
+ * @blue: return value for blue component of color, or %NULL
+ * @alpha: return value for alpha component of color, or %NULL
+ *
+ * Gets the solid color for a solid color pattern.
+ *
+ * Return value: %CAIRO_STATUS_SUCCESS, or
+ * %CAIRO_STATUS_PATTERN_TYPE_MISMATCH if the pattern is not a solid
+ * color pattern.
+ *
+ * Since: 1.4
+ **/
+cairo_status_t
+cairo_pattern_get_rgba (cairo_pattern_t *pattern,
+			double *red, double *green,
+			double *blue, double *alpha)
+{
+    cairo_solid_pattern_t *solid = (cairo_solid_pattern_t*) pattern;
+    double r0, g0, b0, a0;
+
+    if (pattern->status)
+	return pattern->status;
+
+    if (pattern->type != CAIRO_PATTERN_TYPE_SOLID)
+	return _cairo_error (CAIRO_STATUS_PATTERN_TYPE_MISMATCH);
+
+    _cairo_color_get_rgba (&solid->color, &r0, &g0, &b0, &a0);
+
+    if (red)
+	*red = r0;
+    if (green)
+	*green = g0;
+    if (blue)
+	*blue = b0;
+    if (alpha)
+	*alpha = a0;
+
+    return CAIRO_STATUS_SUCCESS;
+}
+
+/**
+ * cairo_pattern_get_surface:
+ * @pattern: a #cairo_pattern_t
+ * @surface: return value for surface of pattern, or %NULL
+ * 
+ * Gets the surface of a surface pattern.  The reference returned in
+ * @surface is owned by the pattern; the caller should call
+ * cairo_surface_reference() if the surface is to be retained.
+ *
+ * Return value: %CAIRO_STATUS_SUCCESS, or
+ * %CAIRO_STATUS_PATTERN_TYPE_MISMATCH if the pattern is not a surface
+ * pattern.
+ *
+ * Since: 1.4
+ **/
+cairo_status_t
+cairo_pattern_get_surface (cairo_pattern_t *pattern,
+			   cairo_surface_t **surface)
+{
+    cairo_surface_pattern_t *spat = (cairo_surface_pattern_t*) pattern;
+
+    if (pattern->status)
+	return pattern->status;
+
+    if (pattern->type != CAIRO_PATTERN_TYPE_SURFACE)
+	return _cairo_error (CAIRO_STATUS_PATTERN_TYPE_MISMATCH);
+
+    if (surface)
+	*surface = spat->surface;
+
+    return CAIRO_STATUS_SUCCESS;
+}
+
+/**
+ * cairo_pattern_get_color_stop_rgba:
+ * @pattern: a #cairo_pattern_t
+ * @index: index of the stop to return data for
+ * @offset: return value for the offset of the stop, or %NULL
+ * @red: return value for red component of color, or %NULL
+ * @green: return value for green component of color, or %NULL
+ * @blue: return value for blue component of color, or %NULL
+ * @alpha: return value for alpha component of color, or %NULL
+ *
+ * Gets the color and offset information at the given @index for a
+ * gradient pattern.  Values of @index are 0 to 1 less than the number
+ * returned by cairo_pattern_get_color_stop_count().
+ *
+ * Return value: %CAIRO_STATUS_SUCCESS, or %CAIRO_STATUS_INVALID_INDEX
+ * if @index is not valid for the given pattern.  If the pattern is
+ * not a gradient pattern, %CAIRO_STATUS_PATTERN_TYPE_MISMATCH is
+ * returned.
+ *
+ * Since: 1.4
+ **/
+cairo_status_t
+cairo_pattern_get_color_stop_rgba (cairo_pattern_t *pattern,
+				   int index, double *offset,
+				   double *red, double *green,
+				   double *blue, double *alpha)
+{
+    cairo_gradient_pattern_t *gradient = (cairo_gradient_pattern_t*) pattern;
+
+    if (pattern->status)
+	return pattern->status;
+
+    if (pattern->type != CAIRO_PATTERN_TYPE_LINEAR &&
+	pattern->type != CAIRO_PATTERN_TYPE_RADIAL)
+	return _cairo_error (CAIRO_STATUS_PATTERN_TYPE_MISMATCH);
+
+    if (index < 0 || (unsigned int) index >= gradient->n_stops)
+	return _cairo_error (CAIRO_STATUS_INVALID_INDEX);
+
+    if (offset)
+	*offset = gradient->stops[index].offset;
+    if (red)
+	*red = gradient->stops[index].color.red;
+    if (green)
+	*green = gradient->stops[index].color.green;
+    if (blue)
+	*blue = gradient->stops[index].color.blue;
+    if (alpha)
+	*alpha = gradient->stops[index].color.alpha;
+
+    return CAIRO_STATUS_SUCCESS;
+}
+
+/**
+ * cairo_pattern_get_color_stop_count:
+ * @pattern: a #cairo_pattern_t
+ * @count: return value for the number of color stops, or %NULL
+ *
+ * Gets the number of color stops specified in the given gradient
+ * pattern.
+ *
+ * Return value: %CAIRO_STATUS_SUCCESS, or
+ * %CAIRO_STATUS_PATTERN_TYPE_MISMATCH if @pattern is not a gradient
+ * pattern.
+ *
+ * Since: 1.4
+ **/
+cairo_status_t
+cairo_pattern_get_color_stop_count (cairo_pattern_t *pattern,
+				    int *count)
+{
+    cairo_gradient_pattern_t *gradient = (cairo_gradient_pattern_t*) pattern;
+
+    if (pattern->status)
+	return pattern->status;
+
+    if (pattern->type != CAIRO_PATTERN_TYPE_LINEAR &&
+	pattern->type != CAIRO_PATTERN_TYPE_RADIAL)
+	return _cairo_error (CAIRO_STATUS_PATTERN_TYPE_MISMATCH);
+
+    if (count)
+	*count = gradient->n_stops;
+
+    return CAIRO_STATUS_SUCCESS;
+}
+
+/**
+ * cairo_pattern_get_linear_points:
+ * @pattern: a #cairo_pattern_t
+ * @x0: return value for the x coordinate of the first point, or %NULL
+ * @y0: return value for the y coordinate of the first point, or %NULL
+ * @x1: return value for the x coordinate of the second point, or %NULL
+ * @y1: return value for the y coordinate of the second point, or %NULL
+ *
+ * Gets the gradient endpoints for a linear gradient.
+ *
+ * Return value: %CAIRO_STATUS_SUCCESS, or
+ * %CAIRO_STATUS_PATTERN_TYPE_MISMATCH if @pattern is not a linear
+ * gradient pattern.
+ *
+ * Since: 1.4
+ **/
+cairo_status_t
+cairo_pattern_get_linear_points (cairo_pattern_t *pattern,
+				 double *x0, double *y0,
+				 double *x1, double *y1)
+{
+    cairo_linear_pattern_t *linear = (cairo_linear_pattern_t*) pattern;
+
+    if (pattern->status)
+	return pattern->status;
+
+    if (pattern->type != CAIRO_PATTERN_TYPE_LINEAR)
+	return _cairo_error (CAIRO_STATUS_PATTERN_TYPE_MISMATCH);
+
+    if (x0)
+	*x0 = linear->pd1.x;
+    if (y0)
+	*y0 = linear->pd1.y;
+    if (x1)
+	*x1 = linear->pd2.x;
+    if (y1)
+	*y1 = linear->pd2.y;
+
+    return CAIRO_STATUS_SUCCESS;
+}
+
+/**
+ * cairo_pattern_get_radial_circles:
+ * @pattern: a #cairo_pattern_t
+ * @x0: return value for the x coordinate of the center of the first circle, or %NULL
+ * @y0: return value for the y coordinate of the center of the first circle, or %NULL
+ * @r0: return value for the radius of the first circle, or %NULL
+ * @x1: return value for the x coordinate of the center of the second circle, or %NULL
+ * @y1: return value for the y coordinate of the center of the second circle, or %NULL
+ * @r1: return value for the radius of the second circle, or %NULL
+ *
+ * Gets the gradient endpoint circles for a radial gradient, each
+ * specified as a center coordinate and a radius.
+ *
+ * Return value: %CAIRO_STATUS_SUCCESS, or
+ * %CAIRO_STATUS_PATTERN_TYPE_MISMATCH if @pattern is not a radial
+ * gradient pattern.
+ *
+ * Since: 1.4
+ **/
+cairo_status_t
+cairo_pattern_get_radial_circles (cairo_pattern_t *pattern,
+				  double *x0, double *y0, double *r0,
+				  double *x1, double *y1, double *r1)
+{
+    cairo_radial_pattern_t *radial = (cairo_radial_pattern_t*) pattern;
+
+    if (pattern->status)
+	return pattern->status;
+
+    if (pattern->type != CAIRO_PATTERN_TYPE_RADIAL)
+	return _cairo_error (CAIRO_STATUS_PATTERN_TYPE_MISMATCH);
+
+    if (x0)
+	*x0 = radial->cd1.center.x;
+    if (y0)
+	*y0 = radial->cd1.center.y;
+    if (r0)
+	*r0 = radial->cd1.radius;
+    if (x1)
+	*x1 = radial->cd2.center.x;
+    if (y1)
+	*y1 = radial->cd2.center.y;
+    if (r1)
+	*r1 = radial->cd2.radius;
+
+    return CAIRO_STATUS_SUCCESS;
+}
+
+/**
+ * cairo_mesh_pattern_get_patch_count:
+ * @pattern: a #cairo_pattern_t
+ * @count: return value for the number patches, or %NULL
+ *
+ * Gets the number of patches specified in the given mesh pattern.
+ *
+ * The number only includes patches which have been finished by
+ * calling cairo_mesh_pattern_end_patch(). For example it will be 0
+ * during the definition of the first patch.
+ *
+ * Return value: %CAIRO_STATUS_SUCCESS, or
+ * %CAIRO_STATUS_PATTERN_TYPE_MISMATCH if @pattern is not a mesh
+ * pattern.
+ *
+ * Since: 1.12
+ **/
+cairo_status_t
+cairo_mesh_pattern_get_patch_count (cairo_pattern_t *pattern,
+				    unsigned int *count)
+{
+    cairo_mesh_pattern_t *mesh = (cairo_mesh_pattern_t *) pattern;
+
+    if (unlikely (pattern->status))
+	return pattern->status;
+
+    if (unlikely (pattern->type != CAIRO_PATTERN_TYPE_MESH))
+	return _cairo_error (CAIRO_STATUS_PATTERN_TYPE_MISMATCH);
+
+    if (count) {
+	*count = _cairo_array_num_elements (&mesh->patches);
+	if (mesh->current_patch)
+	    *count -= 1;
+    }
+
+    return CAIRO_STATUS_SUCCESS;
+}
+slim_hidden_def (cairo_mesh_pattern_get_patch_count);
+
+/**
+ * cairo_mesh_pattern_get_path:
+ * @pattern: a #cairo_pattern_t
+ * @patch_num: the patch number to return data for
+ *
+ * Gets path defining the patch @patch_num for a mesh
+ * pattern.
+ *
+ * @patch_num can range 0 to 1 less than the number returned by
+ * cairo_mesh_pattern_get_patch_count().
+ *
+ * Return value: the path defining the patch, or a path with status
+ * %CAIRO_STATUS_INVALID_INDEX if @patch_num or @point_num is not
+ * valid for @pattern. If @pattern is not a mesh pattern, a path with
+ * status %CAIRO_STATUS_PATTERN_TYPE_MISMATCH is returned.
+ *
+ * Since: 1.12
+ **/
+cairo_path_t *
+cairo_mesh_pattern_get_path (cairo_pattern_t *pattern,
+			     unsigned int patch_num)
+{
+    cairo_mesh_pattern_t *mesh = (cairo_mesh_pattern_t *) pattern;
+    const cairo_mesh_patch_t *patch;
+    cairo_path_t *path;
+    cairo_path_data_t *data;
+    unsigned int patch_count;
+    int l, current_point;
+
+    if (unlikely (pattern->status))
+	return _cairo_path_create_in_error (pattern->status);
+
+    if (unlikely (pattern->type != CAIRO_PATTERN_TYPE_MESH))
+	return _cairo_path_create_in_error (_cairo_error (CAIRO_STATUS_PATTERN_TYPE_MISMATCH));
+
+    patch_count = _cairo_array_num_elements (&mesh->patches);
+    if (mesh->current_patch)
+	patch_count--;
+
+    if (unlikely (patch_num >= patch_count))
+	return _cairo_path_create_in_error (_cairo_error (CAIRO_STATUS_INVALID_INDEX));
+
+    patch = _cairo_array_index_const (&mesh->patches, patch_num);
+
+    if (patch == NULL)
+	return _cairo_path_create_in_error (_cairo_error (CAIRO_STATUS_INVALID_INDEX));
+
+    path = malloc (sizeof (cairo_path_t));
+    if (path == NULL)
+	return _cairo_path_create_in_error (_cairo_error (CAIRO_STATUS_NO_MEMORY));
+
+    path->num_data = 18;
+    path->data = _cairo_malloc_ab (path->num_data,
+				   sizeof (cairo_path_data_t));
+    if (path->data == NULL) {
+	free (path);
+	return _cairo_path_create_in_error (_cairo_error (CAIRO_STATUS_NO_MEMORY));
+    }
+
+    data = path->data;
+    data[0].header.type = CAIRO_PATH_MOVE_TO;
+    data[0].header.length = 2;
+    data[1].point.x = patch->points[0][0].x;
+    data[1].point.y = patch->points[0][0].y;
+    data += data[0].header.length;
+
+    current_point = 0;
+
+    for (l = 0; l < 4; l++) {
+	int i, j, k;
+
+	data[0].header.type = CAIRO_PATH_CURVE_TO;
+	data[0].header.length = 4;
+
+	for (k = 1; k < 4; k++) {
+	    current_point = (current_point + 1) % 12;
+	    i = mesh_path_point_i[current_point];
+	    j = mesh_path_point_j[current_point];
+	    data[k].point.x = patch->points[i][j].x;
+	    data[k].point.y = patch->points[i][j].y;
+	}
+
+	data += data[0].header.length;
+    }
+
+    path->status = CAIRO_STATUS_SUCCESS;
+
+    return path;
+}
+slim_hidden_def (cairo_mesh_pattern_get_path);
+
+/**
+ * cairo_mesh_pattern_get_corner_color_rgba:
+ * @pattern: a #cairo_pattern_t
+ * @patch_num: the patch number to return data for
+ * @corner_num: the corner number to return data for
+ * @red: return value for red component of color, or %NULL
+ * @green: return value for green component of color, or %NULL
+ * @blue: return value for blue component of color, or %NULL
+ * @alpha: return value for alpha component of color, or %NULL
+ *
+ * Gets the color information in corner @corner_num of patch
+ * @patch_num for a mesh pattern.
+ *
+ * @patch_num can range 0 to 1 less than the number returned by
+ * cairo_mesh_pattern_get_patch_count().
+ *
+ * Valid values for @corner_num are from 0 to 3 and identify the
+ * corners as explained in cairo_pattern_create_mesh().
+ *
+ * Return value: %CAIRO_STATUS_SUCCESS, or %CAIRO_STATUS_INVALID_INDEX
+ * if @patch_num or @corner_num is not valid for @pattern. If
+ * @pattern is not a mesh pattern, %CAIRO_STATUS_PATTERN_TYPE_MISMATCH
+ * is returned.
+ *
+ * Since: 1.12
+ **/
+cairo_status_t
+cairo_mesh_pattern_get_corner_color_rgba (cairo_pattern_t *pattern,
+					  unsigned int patch_num,
+					  unsigned int corner_num,
+					  double *red, double *green,
+					  double *blue, double *alpha)
+{
+    cairo_mesh_pattern_t *mesh = (cairo_mesh_pattern_t *) pattern;
+    unsigned int patch_count;
+    const cairo_mesh_patch_t *patch;
+
+    if (unlikely (pattern->status))
+	return pattern->status;
+
+    if (unlikely (pattern->type != CAIRO_PATTERN_TYPE_MESH))
+	return _cairo_error (CAIRO_STATUS_PATTERN_TYPE_MISMATCH);
+
+    if (unlikely (corner_num > 3))
+	return _cairo_error (CAIRO_STATUS_INVALID_INDEX);
+
+    patch_count = _cairo_array_num_elements (&mesh->patches);
+    if (mesh->current_patch)
+	patch_count--;
+
+    if (unlikely (patch_num >= patch_count))
+	return _cairo_error (CAIRO_STATUS_INVALID_INDEX);
+
+    patch = _cairo_array_index_const (&mesh->patches, patch_num);
+    if (patch == NULL)
+	return _cairo_error(CAIRO_STATUS_NULL_POINTER);
+
+    if (red)
+	*red = patch->colors[corner_num].red;
+    if (green)
+	*green = patch->colors[corner_num].green;
+    if (blue)
+	*blue = patch->colors[corner_num].blue;
+    if (alpha)
+	*alpha = patch->colors[corner_num].alpha;
+
+    return CAIRO_STATUS_SUCCESS;
+}
+slim_hidden_def (cairo_mesh_pattern_get_corner_color_rgba);
+
+/**
+ * cairo_mesh_pattern_get_control_point:
+ * @pattern: a #cairo_pattern_t
+ * @patch_num: the patch number to return data for
+ * @point_num: the control point number to return data for
+ * @x: return value for the x coordinate of the control point, or %NULL
+ * @y: return value for the y coordinate of the control point, or %NULL
+ *
+ * Gets the control point @point_num of patch @patch_num for a mesh
+ * pattern.
+ *
+ * @patch_num can range 0 to 1 less than the number returned by
+ * cairo_mesh_pattern_get_patch_count().
+ *
+ * Valid values for @point_num are from 0 to 3 and identify the
+ * control points as explained in cairo_pattern_create_mesh().
+ *
+ * Return value: %CAIRO_STATUS_SUCCESS, or %CAIRO_STATUS_INVALID_INDEX
+ * if @patch_num or @point_num is not valid for @pattern. If @pattern
+ * is not a mesh pattern, %CAIRO_STATUS_PATTERN_TYPE_MISMATCH is
+ * returned.
+ *
+ * Since: 1.12
+ **/
+cairo_status_t
+cairo_mesh_pattern_get_control_point (cairo_pattern_t *pattern,
+				      unsigned int patch_num,
+				      unsigned int point_num,
+				      double *x, double *y)
+{
+    cairo_mesh_pattern_t *mesh = (cairo_mesh_pattern_t *) pattern;
+    const cairo_mesh_patch_t *patch;
+    unsigned int patch_count;
+    int i, j;
+
+    if (pattern->status)
+	return pattern->status;
+
+    if (pattern->type != CAIRO_PATTERN_TYPE_MESH)
+	return _cairo_error (CAIRO_STATUS_PATTERN_TYPE_MISMATCH);
+
+    if (point_num > 3)
+	return _cairo_error (CAIRO_STATUS_INVALID_INDEX);
+
+    patch_count = _cairo_array_num_elements (&mesh->patches);
+    if (mesh->current_patch)
+	patch_count--;
+
+    if (unlikely (patch_num >= patch_count))
+	return _cairo_error (CAIRO_STATUS_INVALID_INDEX);
+
+    patch = _cairo_array_index_const (&mesh->patches, patch_num);
+    if (patch == NULL)
+	return _cairo_error (CAIRO_STATUS_NULL_POINTER);
+
+    i = mesh_control_point_i[point_num];
+    j = mesh_control_point_j[point_num];
+
+    if (x)
+	*x = patch->points[i][j].x;
+    if (y)
+	*y = patch->points[i][j].y;
+
+    return CAIRO_STATUS_SUCCESS;
+}
+slim_hidden_def (cairo_mesh_pattern_get_control_point);
+
+cairo_status_t
+cairo_pattern_set_sigma (cairo_pattern_t *pattern,
+                         const double     x_sigma,
+                         const double     y_sigma)
+{
+    double x = x_sigma;
+    double y = y_sigma;
+
+    if (pattern->status)
+	return pattern->status;
+
+    if (pattern->filter != CAIRO_FILTER_GAUSSIAN)
+        return CAIRO_STATUS_PATTERN_TYPE_MISMATCH;
+
+    if (pattern->type != CAIRO_PATTERN_TYPE_SURFACE)
+	return CAIRO_STATUS_PATTERN_TYPE_MISMATCH;
+
+
+    if (x < 0.0)
+	x = 0.0;
+    if (y < 0.0)
+	y = 0.0;
+
+    if (pattern->x_sigma == x &&
+	pattern->y_sigma == y)
+        return CAIRO_STATUS_SUCCESS;
+
+    if (x > CAIRO_MAX_BLUR >> 1)
+	x = CAIRO_MAX_BLUR >> 1;
+    if (y > CAIRO_MAX_BLUR >> 1)
+	y = CAIRO_MAX_BLUR >> 1;
+
+    pattern->x_sigma = x;
+    pattern->y_sigma = y;
+    pattern->convolution_changed = TRUE;
+
+    return CAIRO_STATUS_SUCCESS;
+}
+
+cairo_status_t
+cairo_pattern_get_sigma (cairo_pattern_t *pattern,
+                         double          *x_sigma,
+                         double          *y_sigma)
+{
+    if (pattern->status)
+	return pattern->status;
+
+    if (pattern->filter != CAIRO_FILTER_GAUSSIAN)
+	return CAIRO_STATUS_PATTERN_TYPE_MISMATCH;
+
+    if (pattern->type != CAIRO_PATTERN_TYPE_SURFACE)
+	return CAIRO_STATUS_PATTERN_TYPE_MISMATCH;
+
+    *x_sigma = pattern->x_sigma;
+    *y_sigma = pattern->y_sigma;
+    return CAIRO_STATUS_SUCCESS;
+}
+
+cairo_status_t
+_cairo_pattern_create_gaussian_matrix (cairo_pattern_t *pattern,
+				       double		line_width)
+{
+    double x_sigma, y_sigma;
+    unsigned int x_factor, y_factor;
+
+    double x_sigma_sq, y_sigma_sq;
+    int row, col, n;
+    double *buffer;
+    int i, x, y;
+    double u, v;
+    double u1, v1;
+    double sum = 0.0;
+    cairo_rectangle_int_t extents;
+    int width = CAIRO_MIN_SHRINK_SIZE;
+    int height = CAIRO_MIN_SHRINK_SIZE;
+    double min_line_width = (line_width >= 1.0) ? CAIRO_MIN_LINE_WIDTH : line_width;
+    double max_sigma = CAIRO_MAX_SIGMA;
+    double test_line_width = line_width;
+
+    if (pattern->status)
+	return pattern->status;
+
+    if (pattern->filter != CAIRO_FILTER_GAUSSIAN)
+	return CAIRO_STATUS_PATTERN_TYPE_MISMATCH;
+
+    if (pattern->type != CAIRO_PATTERN_TYPE_SURFACE)
+	return CAIRO_STATUS_PATTERN_TYPE_MISMATCH;
+
+    if (! pattern->convolution_changed)
+        return CAIRO_STATUS_SUCCESS;
+
+    if (_cairo_surface_get_extents (((cairo_surface_pattern_t *)pattern)->surface, &extents)) {
+	width = extents.width;
+	height = extents.height;
+    }
+
+    x_factor = 1;
+    y_factor = 1;
+    x_sigma = pattern->x_sigma;
+    y_sigma = pattern->y_sigma;
+
+    /* no blur */
+    if (x_sigma == 0.0 && y_sigma == 0.0) {
+	if (pattern->convolution_matrix)
+	    free (pattern->convolution_matrix);
+	pattern->convolution_matrix = NULL;
+
+        return CAIRO_STATUS_SUCCESS;
+    }
+
+    if (x_sigma == 0.0)
+        pattern->x_radius = 0;
+    else {
+	while (x_sigma >= max_sigma && test_line_width >= min_line_width) {
+	    if (width <= CAIRO_MIN_SHRINK_SIZE)
+		break;
+
+	    x_sigma /= 2.0;
+	    x_factor *= 2;
+	    width *= 0.5;
+	    test_line_width *= 0.5;
+	}
+	if (x_sigma > max_sigma)
+	    x_sigma = max_sigma;
+        /* XXX: skia uses 3, we follow css spec which is 2 */
+	pattern->x_radius = ceil (x_sigma * 2);
+    }
+    pattern->shrink_factor_x = x_factor;
+    test_line_width = line_width;
+
+    if (y_sigma == 0.0)
+        pattern->y_radius = 0;
+    else {
+	while (y_sigma >= max_sigma && test_line_width >= min_line_width) {
+	    if (height <= CAIRO_MIN_SHRINK_SIZE)
+		break;
+
+	    y_sigma *= 0.5;
+	    y_factor *= 2;
+	    height *= 0.5;
+	    test_line_width *= 0.5;
+	}
+	if (y_sigma > max_sigma)
+	    y_sigma = max_sigma;
+	pattern->y_radius = ceil (y_sigma * 2);
+    }
+    pattern->shrink_factor_y = y_factor;
+
+    if (pattern->convolution_matrix)
+	free (pattern->convolution_matrix);
+
+    pattern->convolution_matrix = NULL;
+
+    /* 2D gaussian
+     * f(x, y) = exp (-((x-x0)^2/(2*x_sigma^2)+(y-y0)^2/(2*y_sigma*2)))
+     */
+    row = pattern->y_radius;
+    col = pattern->x_radius;
+    n = (2 * row + 1) * (2 * col + 1);
+
+    x_sigma_sq = 2 * x_sigma * x_sigma;
+    y_sigma_sq = 2 * y_sigma * y_sigma;
+
+    buffer = _cairo_malloc_ab (n, sizeof (double));
+    if (buffer == NULL)
+	return CAIRO_STATUS_NO_MEMORY;
+
+    i = 0;
+    for (y = -row; y <= row; y++) {
+        for (x = - col; x <= col; x++) {
+            u = x * x;
+            v = y * y;
+	    if (u == 0.0)
+		u1 = 0.0;
+	    else
+		u1 = u / x_sigma_sq;
+
+	    if (v == 0.0)
+		v1 = 0.0;
+	    else
+		v1 = v / y_sigma_sq;
+            buffer[i] = exp (-(u1 + v1));
+            sum += buffer[i];
+            i++;
+        }
+    }
+
+    /* normalize */
+    sum = 1.0 / sum;
+    for (i = 0; i < n; i++)
+        buffer[i] *= sum;
+
+    pattern->convolution_matrix = buffer;
+    pattern->convolution_changed = FALSE;
+    return CAIRO_STATUS_SUCCESS;
+}
+
+void
+_cairo_pattern_reset_static_data (void)
+{
+    int i;
+
+    for (i = 0; i < ARRAY_LENGTH (freed_pattern_pool); i++)
+	_freed_pool_reset (&freed_pattern_pool[i]);
+}
+
+static void
+_cairo_debug_print_surface_pattern (FILE *file,
+				    const cairo_surface_pattern_t *pattern)
+{
+    printf ("  surface type: %d\n", pattern->surface->type);
+}
+
+static void
+_cairo_debug_print_raster_source_pattern (FILE *file,
+					  const cairo_raster_source_pattern_t *raster)
+{
+    printf ("  content: %x, size %dx%d\n", raster->content, raster->extents.width, raster->extents.height);
+}
+
+static void
+_cairo_debug_print_linear_pattern (FILE *file,
+				    const cairo_linear_pattern_t *pattern)
+{
+}
+
+static void
+_cairo_debug_print_radial_pattern (FILE *file,
+				   const cairo_radial_pattern_t *pattern)
+{
+}
+
+static void
+_cairo_debug_print_mesh_pattern (FILE *file,
+				 const cairo_mesh_pattern_t *pattern)
+{
+}
+
+void
+_cairo_debug_print_pattern (FILE *file, const cairo_pattern_t *pattern)
+{
+    const char *s;
+    switch (pattern->type) {
+    case CAIRO_PATTERN_TYPE_SOLID: s = "solid"; break;
+    case CAIRO_PATTERN_TYPE_SURFACE: s = "surface"; break;
+    case CAIRO_PATTERN_TYPE_LINEAR: s = "linear"; break;
+    case CAIRO_PATTERN_TYPE_RADIAL: s = "radial"; break;
+    case CAIRO_PATTERN_TYPE_MESH: s = "mesh"; break;
+    case CAIRO_PATTERN_TYPE_RASTER_SOURCE: s = "raster"; break;
+    default: s = "invalid"; ASSERT_NOT_REACHED; break;
+    }
+
+    fprintf (file, "pattern: %s\n", s);
+    if (pattern->type == CAIRO_PATTERN_TYPE_SOLID)
+	return;
+
+    switch (pattern->extend) {
+    case CAIRO_EXTEND_NONE: s = "none"; break;
+    case CAIRO_EXTEND_REPEAT: s = "repeat"; break;
+    case CAIRO_EXTEND_REFLECT: s = "reflect"; break;
+    case CAIRO_EXTEND_PAD: s = "pad"; break;
+    default: s = "invalid"; ASSERT_NOT_REACHED; break;
+    }
+    fprintf (file, "  extend: %s\n", s);
+
+    switch (pattern->filter) {
+    case CAIRO_FILTER_FAST: s = "fast"; break;
+    case CAIRO_FILTER_GOOD: s = "good"; break;
+    case CAIRO_FILTER_BEST: s = "best"; break;
+    case CAIRO_FILTER_NEAREST: s = "nearest"; break;
+    case CAIRO_FILTER_BILINEAR: s = "bilinear"; break;
+    case CAIRO_FILTER_GAUSSIAN: s = "guassian"; break;
+    default: s = "invalid"; ASSERT_NOT_REACHED; break;
+    }
+    fprintf (file, "  filter: %s\n", s);
+    fprintf (file, "  matrix: [%g %g %g %g %g %g]\n",
+	     pattern->matrix.xx, pattern->matrix.yx,
+	     pattern->matrix.xy, pattern->matrix.yy,
+	     pattern->matrix.x0, pattern->matrix.y0);
+    switch (pattern->type) {
+    default:
+    case CAIRO_PATTERN_TYPE_SOLID:
+	break;
+    case CAIRO_PATTERN_TYPE_RASTER_SOURCE:
+	_cairo_debug_print_raster_source_pattern (file, (cairo_raster_source_pattern_t *)pattern);
+	break;
+    case CAIRO_PATTERN_TYPE_SURFACE:
+	_cairo_debug_print_surface_pattern (file, (cairo_surface_pattern_t *)pattern);
+	break;
+    case CAIRO_PATTERN_TYPE_LINEAR:
+	_cairo_debug_print_linear_pattern (file, (cairo_linear_pattern_t *)pattern);
+	break;
+    case CAIRO_PATTERN_TYPE_RADIAL:
+	_cairo_debug_print_radial_pattern (file, (cairo_radial_pattern_t *)pattern);
+	break;
+    case CAIRO_PATTERN_TYPE_MESH:
+	_cairo_debug_print_mesh_pattern (file, (cairo_mesh_pattern_t *)pattern);
+	break;
+    }
+}
+
+static unsigned long
+_cairo_solid_pattern_alpha_hash (unsigned long hash,
+				 const cairo_solid_pattern_t *solid)
+{
+    return _cairo_hash_bytes (hash, &solid->color.alpha, sizeof (double));
+}
+
+unsigned long
+_cairo_pattern_hash_with_hash (unsigned long hash,
+			       const cairo_pattern_t *pattern,
+			       const cairo_bool_t use_color)
+{
+    if (pattern->status)
+	return hash;
+
+    hash = _cairo_hash_bytes (hash, &pattern->type, sizeof (pattern->type));
+    if (pattern->type != CAIRO_PATTERN_TYPE_SOLID) {
+	hash = _cairo_hash_bytes (hash, &pattern->matrix, sizeof (double) * 4);
+	hash = _cairo_hash_bytes (hash,
+				  &pattern->filter, sizeof (pattern->filter));
+	hash = _cairo_hash_bytes (hash,
+				  &pattern->extend, sizeof (pattern->extend));
+	hash = _cairo_hash_bytes (hash,
+				  &pattern->has_component_alpha,
+				  sizeof (pattern->has_component_alpha));
+    }
+
+    if (pattern->type == CAIRO_PATTERN_TYPE_SURFACE)
+	hash = _cairo_hash_bytes (hash, &pattern->x_sigma, sizeof (double) * 2);
+
+    switch (pattern->type) {
+    case CAIRO_PATTERN_TYPE_SOLID:
+	if (use_color)
+	    return _cairo_solid_pattern_hash (hash, (cairo_solid_pattern_t *) pattern);
+	else
+	    return _cairo_solid_pattern_alpha_hash (hash, (cairo_solid_pattern_t *) pattern);
+    case CAIRO_PATTERN_TYPE_LINEAR:
+	return _cairo_linear_pattern_hash (hash, (cairo_linear_pattern_t *) pattern);
+    case CAIRO_PATTERN_TYPE_RADIAL:
+	return _cairo_radial_pattern_hash (hash, (cairo_radial_pattern_t *) pattern);
+    case CAIRO_PATTERN_TYPE_MESH:
+	return _cairo_mesh_pattern_hash (hash, (cairo_mesh_pattern_t *) pattern);
+    case CAIRO_PATTERN_TYPE_SURFACE:
+	return _cairo_surface_pattern_hash (hash, (cairo_surface_pattern_t *) pattern);
+    case CAIRO_PATTERN_TYPE_RASTER_SOURCE:
+	return _cairo_raster_source_pattern_hash (hash, (cairo_raster_source_pattern_t *) pattern);
+    default:
+	ASSERT_NOT_REACHED;
+	return FALSE;
+    }
+}