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/*
* Copyright © 2008 Chris Wilson
*
* 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>
*/
#include "cairo-test.h"
#define SIZE 60 /* needs to be big to check large area effects (dithering) */
#define PAD 2
static cairo_test_draw_function_t draw;
static const cairo_test_t test = {
"fill-alpha-pattern",
"Tests using set_rgba();fill() over a linear gradient",
2*SIZE + 4*PAD, 2*SIZE + 4*PAD,
draw
};
static cairo_test_status_t
draw (cairo_t *cr, int width, int height)
{
const double alpha = 1./3;
cairo_pattern_t *pattern;
int n;
/* draw a simple pattern behind */
pattern = cairo_pattern_create_linear (0, 0, width, height);
cairo_pattern_add_color_stop_rgb (pattern, 0, 1, 1, 0);
cairo_pattern_add_color_stop_rgb (pattern, 1, 1, 1, 1);
cairo_set_source (cr, pattern);
cairo_pattern_destroy (pattern);
cairo_paint (cr);
/* square */
cairo_rectangle (cr, PAD, PAD, SIZE, SIZE);
cairo_set_source_rgba (cr, 1, 0, 0, alpha);
cairo_fill (cr);
/* circle */
cairo_translate (cr, SIZE + 2 * PAD, 0);
cairo_arc (cr, PAD + SIZE / 2., PAD + SIZE / 2., SIZE / 2., 0, 2 * M_PI);
cairo_set_source_rgba (cr, 0, 1, 0, alpha);
cairo_fill (cr);
/* triangle */
cairo_translate (cr, 0, SIZE + 2 * PAD);
cairo_move_to (cr, PAD + SIZE / 2, PAD);
cairo_line_to (cr, PAD + SIZE, PAD + SIZE);
cairo_line_to (cr, PAD, PAD + SIZE);
cairo_set_source_rgba (cr, 0, 0, 1, alpha);
cairo_fill (cr);
/* star */
cairo_translate (cr, -(SIZE + 2 * PAD) + SIZE/2., SIZE/2.);
for (n = 0; n < 5; n++) {
cairo_line_to (cr,
SIZE/2 * cos (2*n * 2*M_PI / 10),
SIZE/2 * sin (2*n * 2*M_PI / 10));
cairo_line_to (cr,
SIZE/4 * cos ((2*n+1)*2*M_PI / 10),
SIZE/4 * sin ((2*n+1)*2*M_PI / 10));
}
cairo_set_source_rgba (cr, 0, 0, 0, alpha);
cairo_fill (cr);
return CAIRO_TEST_SUCCESS;
}
int
main (void)
{
return cairo_test (&test);
}
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