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+/*
+ * Copyright 2010 Intel Corporation
+ *
+ * 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.
+ *
+ * Author: Chris Wilson <chris@chris-wilson.co.uk>
+ */
+
+#include "cairo-test.h"
+
+/* A fun little test to explore color fringing in various experimental
+ * subpixel rasterisation techniques.
+ */
+
+#define WIDTH 60
+#define HEIGHT 40
+
+static const struct color {
+ double red, green, blue;
+} color[] = {
+ { 1, 1, 1 },
+ { 0, 0, 0 },
+ { 1, 0, 0 },
+ { 0, 1, 0 },
+ { 0, 0, 1 },
+ { 1, 1, 0 },
+ { 0, 1, 1 },
+ { 1, 0, 1 },
+ { .5, .5, .5 },
+};
+
+#define NUM_COLORS ARRAY_LENGTH (color)
+
+static void
+object (cairo_t *cr, const struct color *fg, const struct color *bg)
+{
+ cairo_set_source_rgb (cr, bg->red, bg->green, bg->blue);
+ cairo_rectangle (cr, 0, 0, WIDTH, HEIGHT);
+ cairo_fill (cr);
+
+ cairo_set_source_rgb (cr, fg->red, fg->green, fg->blue);
+ cairo_save (cr);
+ cairo_scale (cr, WIDTH, HEIGHT);
+ cairo_arc (cr, .5, .5, .5 - 4. / MAX (WIDTH, HEIGHT), 0, 2 * M_PI);
+ cairo_fill (cr);
+ cairo_arc (cr, .5, .5, .5 - 2. / MAX (WIDTH, HEIGHT), 0, 2 * M_PI);
+ cairo_restore (cr);
+ cairo_set_line_width (cr, 1.);
+ cairo_stroke (cr);
+
+ cairo_set_source_rgb (cr, bg->red, bg->green, bg->blue);
+ cairo_set_line_width (cr, 4.);
+ cairo_move_to (cr, 4, HEIGHT-4);
+ cairo_line_to (cr, WIDTH-12, 4);
+ cairo_move_to (cr, 12, HEIGHT-4);
+ cairo_line_to (cr, WIDTH-4, 4);
+ cairo_stroke (cr);
+}
+
+static cairo_test_status_t
+draw (cairo_t *cr, int width, int height)
+{
+ unsigned int i, j;
+
+ for (i = 0; i < NUM_COLORS; i++) {
+ for (j = 0; j < NUM_COLORS; j++) {
+ cairo_save (cr);
+ cairo_translate (cr, i * WIDTH, j * HEIGHT);
+ object (cr, &color[i], &color[j]);
+ cairo_restore (cr);
+ }
+ }
+
+ return CAIRO_TEST_SUCCESS;
+}
+
+CAIRO_TEST (aliasing,
+ "Check for subpixel aliasing and color fringing",
+ "rasterisation", /* keywords */
+ "target=raster", /* requirements */
+ NUM_COLORS * WIDTH, NUM_COLORS * HEIGHT,
+ NULL, draw)