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/*
* Copyright 2011 Intel Corporation
*
* Permission to use, copy, modify, distribute, and sell this software
* and its documentation for any purpose is hereby granted without
* fee, provided that the above copyright notice appear in all copies
* and that both that copyright notice and this permission notice
* appear in supporting documentation, and that the name of
* Chris Wilson not be used in advertising or publicity pertaining to
* distribution of the software without specific, written prior
* permission. Chris Wilson makes no representations about the
* suitability of this software for any purpose. It is provided "as
* is" without express or implied warranty.
*
* CHRIS WILSON DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS
* SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
* FITNESS, IN NO EVENT SHALL CHRIS WILSON BE LIABLE FOR ANY SPECIAL,
* INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER
* RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
* OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR
* IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*
* Author: Chris Wilson <chris@chris-wilson.co.uk>
*/
/* Exercises a bug spotted by Andrea Canciani where the polygon clipping
* code was hopeless broken with horizontal edges.
*/
#include "cairo-test.h"
#define WIDTH 16
#define HEIGHT 26
#define BUGY 1
#define BUGX (4 * BUGY * WIDTH * 256)
static cairo_test_status_t
draw (cairo_t *cr, int width, int height)
{
cairo_set_source_rgb (cr, 1, 1, 1);
cairo_paint (cr);
cairo_set_source_rgb (cr, 0, 0, 0);
cairo_move_to (cr, - BUGX, 6 - BUGY);
cairo_line_to (cr, + BUGX, 6 + BUGY);
cairo_line_to (cr, WIDTH + BUGX, 2 - BUGY);
cairo_line_to (cr, WIDTH - BUGX, 2 + BUGY);
cairo_fill (cr);
cairo_move_to (cr, WIDTH + BUGX, 8 - BUGY);
cairo_line_to (cr, WIDTH - BUGX, 8 + BUGY);
cairo_line_to (cr, - BUGX, 12 - BUGY);
cairo_line_to (cr, + BUGX, 12 + BUGY);
cairo_fill (cr);
cairo_move_to (cr, - BUGX, 14 - BUGY);
cairo_line_to (cr, + BUGX, 14 + BUGY);
cairo_line_to (cr, WIDTH + BUGX, 18 - BUGY);
cairo_line_to (cr, WIDTH - BUGX, 18 + BUGY);
cairo_fill (cr);
cairo_move_to (cr, WIDTH + BUGX, 24 - BUGY);
cairo_line_to (cr, WIDTH - BUGX, 24 + BUGY);
cairo_line_to (cr, - BUGX, 20 - BUGY);
cairo_line_to (cr, + BUGX, 20 + BUGY);
cairo_fill (cr);
return CAIRO_TEST_SUCCESS;
}
CAIRO_TEST (horizontal_clip,
"Tests intersection of a nearly horizontal lines with a clipped polygon",
"clip, fill", /* keywords */
NULL, /* requirements */
WIDTH, HEIGHT,
NULL, draw)
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