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diff --git a/src/cairo-color.c b/src/cairo-color.c
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+/* cairo - a vector graphics library with display and print output
+ *
+ * Copyright © 2002 University of Southern California
+ * Copyright © 2005 Red Hat, Inc.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it either under the terms of the GNU Lesser General Public
+ * License version 2.1 as published by the Free Software Foundation
+ * (the "LGPL") or, at your option, under the terms of the Mozilla
+ * Public License Version 1.1 (the "MPL"). If you do not alter this
+ * notice, a recipient may use your version of this file under either
+ * the MPL or the LGPL.
+ *
+ * You should have received a copy of the LGPL along with this library
+ * in the file COPYING-LGPL-2.1; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Suite 500, Boston, MA 02110-1335, USA
+ * You should have received a copy of the MPL along with this library
+ * in the file COPYING-MPL-1.1
+ *
+ * The contents of this file are subject to the Mozilla Public License
+ * Version 1.1 (the "License"); you may not use this file except in
+ * compliance with the License. You may obtain a copy of the License at
+ * http://www.mozilla.org/MPL/
+ *
+ * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY
+ * OF ANY KIND, either express or implied. See the LGPL or the MPL for
+ * the specific language governing rights and limitations.
+ *
+ * The Original Code is the cairo graphics library.
+ *
+ * The Initial Developer of the Original Code is University of Southern
+ * California.
+ *
+ * Contributor(s):
+ * Carl D. Worth <cworth@cworth.org>
+ */
+
+#include "cairoint.h"
+
+static cairo_color_t const cairo_color_white = {
+ 1.0, 1.0, 1.0, 1.0,
+ 0xffff, 0xffff, 0xffff, 0xffff
+};
+
+static cairo_color_t const cairo_color_black = {
+ 0.0, 0.0, 0.0, 1.0,
+ 0x0, 0x0, 0x0, 0xffff
+};
+
+static cairo_color_t const cairo_color_transparent = {
+ 0.0, 0.0, 0.0, 0.0,
+ 0x0, 0x0, 0x0, 0x0
+};
+
+static cairo_color_t const cairo_color_magenta = {
+ 1.0, 0.0, 1.0, 1.0,
+ 0xffff, 0x0, 0xffff, 0xffff
+};
+
+const cairo_color_t *
+_cairo_stock_color (cairo_stock_t stock)
+{
+ switch (stock) {
+ case CAIRO_STOCK_WHITE:
+ return &cairo_color_white;
+ case CAIRO_STOCK_BLACK:
+ return &cairo_color_black;
+ case CAIRO_STOCK_TRANSPARENT:
+ return &cairo_color_transparent;
+
+ case CAIRO_STOCK_NUM_COLORS:
+ default:
+ ASSERT_NOT_REACHED;
+ /* If the user can get here somehow, give a color that indicates a
+ * problem. */
+ return &cairo_color_magenta;
+ }
+}
+
+/* Convert a double in [0.0, 1.0] to an integer in [0, 65535]
+ * The conversion is designed to choose the integer i such that
+ * i / 65535.0 is as close as possible to the input value.
+ */
+uint16_t
+_cairo_color_double_to_short (double d)
+{
+ return d * 65535.0 + 0.5;
+}
+
+static void
+_cairo_color_compute_shorts (cairo_color_t *color)
+{
+ color->red_short = _cairo_color_double_to_short (color->red * color->alpha);
+ color->green_short = _cairo_color_double_to_short (color->green * color->alpha);
+ color->blue_short = _cairo_color_double_to_short (color->blue * color->alpha);
+ color->alpha_short = _cairo_color_double_to_short (color->alpha);
+}
+
+void
+_cairo_color_init_rgba (cairo_color_t *color,
+ double red, double green, double blue,
+ double alpha)
+{
+ color->red = red;
+ color->green = green;
+ color->blue = blue;
+ color->alpha = alpha;
+
+ _cairo_color_compute_shorts (color);
+}
+
+void
+_cairo_color_multiply_alpha (cairo_color_t *color,
+ double alpha)
+{
+ color->alpha *= alpha;
+
+ _cairo_color_compute_shorts (color);
+}
+
+void
+_cairo_color_get_rgba (cairo_color_t *color,
+ double *red,
+ double *green,
+ double *blue,
+ double *alpha)
+{
+ *red = color->red;
+ *green = color->green;
+ *blue = color->blue;
+ *alpha = color->alpha;
+}
+
+void
+_cairo_color_get_rgba_premultiplied (cairo_color_t *color,
+ double *red,
+ double *green,
+ double *blue,
+ double *alpha)
+{
+ *red = color->red * color->alpha;
+ *green = color->green * color->alpha;
+ *blue = color->blue * color->alpha;
+ *alpha = color->alpha;
+}
+
+/* NB: This function works both for unmultiplied and premultiplied colors */
+cairo_bool_t
+_cairo_color_equal (const cairo_color_t *color_a,
+ const cairo_color_t *color_b)
+{
+ if (color_a == color_b)
+ return TRUE;
+
+ if (color_a->alpha_short != color_b->alpha_short)
+ return FALSE;
+
+ if (color_a->alpha_short == 0)
+ return TRUE;
+
+ return color_a->red_short == color_b->red_short &&
+ color_a->green_short == color_b->green_short &&
+ color_a->blue_short == color_b->blue_short;
+}
+
+cairo_bool_t
+_cairo_color_stop_equal (const cairo_color_stop_t *color_a,
+ const cairo_color_stop_t *color_b)
+{
+ if (color_a == color_b)
+ return TRUE;
+
+ return color_a->alpha_short == color_b->alpha_short &&
+ color_a->red_short == color_b->red_short &&
+ color_a->green_short == color_b->green_short &&
+ color_a->blue_short == color_b->blue_short;
+}
+
+cairo_content_t
+_cairo_color_get_content (const cairo_color_t *color)
+{
+ if (CAIRO_COLOR_IS_OPAQUE (color))
+ return CAIRO_CONTENT_COLOR;
+
+ if (color->red_short == 0 &&
+ color->green_short == 0 &&
+ color->blue_short == 0)
+ {
+ return CAIRO_CONTENT_ALPHA;
+ }
+
+ return CAIRO_CONTENT_COLOR_ALPHA;
+}