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/*
* Copyright © 2011 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>
*/
/* Not strictly overlapping, but it does highlight the error in
* an optimisation of fill-box handling that I frequently am
* tempted to write.
*/
#include "cairo-test.h"
#define WIDTH (20)
#define HEIGHT (20)
static void
border (cairo_t *cr)
{
cairo_rectangle (cr, 1, 1, 8, 8);
cairo_rectangle (cr, 1.25, 1.25, 7.5, 7.5);
cairo_rectangle (cr, 1.75, 1.75, 6.5, 6.5);
cairo_rectangle (cr, 2, 2, 6, 6);
}
static cairo_test_status_t
draw (cairo_t *cr, int width, int height)
{
cairo_set_fill_rule (cr, CAIRO_FILL_RULE_EVEN_ODD);
cairo_set_source_rgb (cr, 1, 1, 1);
cairo_paint (cr);
border (cr);
cairo_set_source_rgb (cr, 1, 0, 0);
cairo_set_operator (cr, CAIRO_OPERATOR_OVER);
cairo_fill (cr);
cairo_translate (cr, 10, 0);
border (cr);
cairo_set_source_rgb (cr, 0, 0, 1);
cairo_set_operator (cr, CAIRO_OPERATOR_SOURCE);
cairo_fill (cr);
cairo_translate (cr, 0, 10);
cairo_rectangle (cr, 0, 0, 10, 10);
cairo_clip (cr);
border (cr);
cairo_set_source_rgb (cr, 0, 1, 0);
cairo_set_operator (cr, CAIRO_OPERATOR_IN);
cairo_fill (cr);
cairo_reset_clip (cr);
cairo_translate (cr, -10, 0);
cairo_rectangle (cr, 0, 0, 10, 10);
cairo_clip (cr);
border (cr);
cairo_set_source_rgb (cr, 0, 0, 1);
cairo_set_operator (cr, CAIRO_OPERATOR_CLEAR);
cairo_fill (cr);
return CAIRO_TEST_SUCCESS;
}
CAIRO_TEST (overlapping_boxes,
"A sub-pixel double border to highlight the danger in an easy optimisation",
"fill", /* keywords */
NULL, /* requirements */
WIDTH, HEIGHT,
NULL, draw)
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