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/*
* Copyright © 2006 M Joonas Pihlaja
*
* 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: M Joonas Pihlaja <jpihlaja@cc.helsinki.fi>
*/
/* Bug history
*
* 2006-12-05 M Joonas Pihlaja <jpihlaja@cc.helsinki.fi>
*
* The cairo_in_fill () function can sometimes produce false
* positives when the tessellator produces empty trapezoids
* and the query point lands exactly on a trapezoid edge.
*/
#include "cairo-test.h"
static cairo_test_status_t
preamble (cairo_test_context_t *ctx)
{
int x,y;
int width = 10;
int height = 10;
cairo_surface_t *surf;
cairo_t *cr;
int false_positive_count = 0;
cairo_status_t status;
cairo_test_status_t ret;
surf = cairo_image_surface_create (CAIRO_FORMAT_ARGB32, width, height);
cr = cairo_create (surf);
cairo_surface_destroy (surf);
/* Empty horizontal trapezoid. */
cairo_move_to (cr, 0, height/3);
cairo_line_to (cr, width, height/3);
cairo_close_path (cr);
/* Empty non-horizontal trapezoid #1. */
cairo_move_to (cr, 0, 0);
cairo_line_to (cr, width, height/2);
cairo_close_path (cr);
/* Empty non-horizontal trapezoid #2 intersecting #1. */
cairo_move_to (cr, 0, height/2);
cairo_line_to (cr, width, 0);
cairo_close_path (cr);
status = cairo_status (cr);
/* Point sample the tessellated path. */
for (y = 0; y < height; y++) {
for (x = 0; x < width; x++) {
if (cairo_in_fill (cr, x, y)) {
false_positive_count++;
}
}
}
cairo_destroy (cr);
/* Check that everything went well. */
ret = CAIRO_TEST_SUCCESS;
if (CAIRO_STATUS_SUCCESS != status) {
cairo_test_log (ctx, "Failed to create a test surface and path: %s\n",
cairo_status_to_string (status));
ret = CAIRO_TEST_FAILURE;
}
if (0 != false_positive_count) {
cairo_test_log (ctx, "Point sampling found %d false positives "
"from cairo_in_fill()\n",
false_positive_count);
ret = CAIRO_TEST_FAILURE;
}
return ret;
}
CAIRO_TEST (in_fill_empty_trapezoid,
"Test that the tessellator isn't producing obviously empty trapezoids",
"in, trap", /* keywords */
NULL, /* requirements */
0, 0,
preamble, NULL)
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