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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)
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