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+/*
+ * Copyright © 2008 Red Hat, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person
+ * obtaining a copy of this software and associated documentation
+ * files (the "Software"), to deal in the Software without
+ * restriction, including without limitation the rights to use, copy,
+ * modify, merge, publish, distribute, sublicense, and/or sell copies
+ * of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ *
+ * Authors: Carl D. Worth <cworth@cworth.org>
+ * Owen Taylor <otaylor@redhat.com>
+ */
+
+#include "cairo-test.h"
+
+/* This test exercises code that computes the extents of a surface
+ * pattern with CAIRO_FILTER_BILINEAR, (where the filtering
+ * effectively increases the extents of the pattern).
+ *
+ * The original bug was reported by Owen Taylor here:
+ *
+ * bad clipping with EXTEND_NONE
+ * http://bugs.freedesktop.org/show_bug.cgi?id=15349
+ */
+
+#define SCALE 10
+#define PAD 3
+#define WIDTH (PAD + 3 * SCALE + PAD)
+#define HEIGHT WIDTH
+
+static cairo_test_status_t
+draw (cairo_t *cr, int width, int height)
+{
+ cairo_surface_t *image;
+ cairo_t *cr2;
+
+ image = cairo_image_surface_create (CAIRO_FORMAT_RGB24, 2, 2);
+
+ /* Fill with an opaque background to avoid a separate rgb24 ref image */
+ cairo_set_source_rgb (cr, 0, 0, 0);
+ cairo_paint (cr);
+
+ /* First check handling of pattern extents > surface extents */
+ cairo_save (cr);
+ cairo_scale (cr, width/2., height/2.);
+
+ /* Create a solid black source to merge with the background */
+ cr2 = cairo_create (image);
+ cairo_set_source_rgb (cr2, 0, 0 ,0);
+ cairo_paint (cr2);
+ cairo_set_source_surface (cr, cairo_get_target (cr2), 0, 0);
+ cairo_destroy (cr2);
+ cairo_pattern_set_filter (cairo_get_source (cr), CAIRO_FILTER_BILINEAR);
+ cairo_paint (cr);
+ cairo_restore (cr);
+
+ /* Then scale to smaller so we can see the full bilinear extents */
+ cairo_save (cr);
+ cairo_translate (cr, PAD, PAD);
+ cairo_scale (cr, SCALE, SCALE);
+ cairo_translate (cr, 0.5, 0.5);
+
+ /* Create a 2x2 blue+red checkerboard source */
+ cr2 = cairo_create (image);
+ cairo_set_source_rgb (cr2, 1, 0 ,0); /* red */
+ cairo_paint (cr2);
+ cairo_set_source_rgb (cr2, 0, 0, 1); /* blue */
+ cairo_rectangle (cr2, 0, 1, 1, 1);
+ cairo_rectangle (cr2, 1, 0, 1, 1);
+ cairo_fill (cr2);
+ cairo_set_source_surface (cr, cairo_get_target (cr2), 0, 0);
+ cairo_destroy (cr2);
+
+ cairo_pattern_set_filter (cairo_get_source (cr), CAIRO_FILTER_BILINEAR);
+ cairo_paint (cr);
+ cairo_restore (cr);
+
+ cairo_surface_destroy (image);
+
+ return CAIRO_TEST_SUCCESS;
+}
+
+CAIRO_TEST (filter_bilinear_extents,
+ "Test that pattern extents are properly computed for CAIRO_FILTER_BILINEAR",
+ "extents", /* keywords */
+ NULL, /* requirements */
+ WIDTH, HEIGHT,
+ NULL, draw)