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/*
* Copyright © 2005 Red Hat, Inc.
* Copyright © 2006 Red Hat, Inc.
*
* 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
* Red Hat, Inc. not be used in advertising or publicity pertaining to
* distribution of the software without specific, written prior
* permission. Red Hat, Inc. makes no representations about the
* suitability of this software for any purpose. It is provided "as
* is" without express or implied warranty.
*
* RED HAT, INC. DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS
* SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
* FITNESS, IN NO EVENT SHALL RED HAT, INC. 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: Carl D. Worth <cworth@cworth.org>
*/
#include "cairo-test.h"
#define PAD 2
#define SIZE 10
static cairo_test_draw_function_t draw;
static const cairo_test_t test = {
"fill-and-stroke-alpha-add",
"Use a group to fill/stroke a path (each with different alpha) using DEST_OUT and ADD to combine",
2 * SIZE + 4 * PAD, SIZE + 2 * PAD,
draw
};
typedef void (*path_func_t) (cairo_t *cr);
static void
rectangle (cairo_t *cr)
{
cairo_rectangle (cr, PAD, PAD, SIZE, SIZE);
}
static void
circle (cairo_t *cr)
{
cairo_arc (cr,
PAD + SIZE / 2, PAD + SIZE / 2,
SIZE / 2,
0, 2 * M_PI);
}
/* Given a path-generating function and two possibly translucent
* patterns, fill and stroke the path with the patterns (to an
* offscreen group), then blend the result into the destination.
*/
static void
fill_and_stroke (cairo_t *cr,
path_func_t path_func,
cairo_pattern_t *fill_pattern,
cairo_pattern_t *stroke_pattern)
{
cairo_push_group (cr);
{
(path_func) (cr);
cairo_set_source (cr, fill_pattern);
cairo_fill_preserve (cr);
/* Use DEST_OUT to subtract stroke from fill. */
cairo_set_source_rgb (cr, 0.0, 0.0, 0.0);
cairo_set_operator (cr, CAIRO_OPERATOR_DEST_OUT);
cairo_stroke_preserve (cr);
/* Then use ADD to draw the stroke without a seam. */
cairo_set_source (cr, stroke_pattern);
cairo_set_operator (cr, CAIRO_OPERATOR_ADD);
cairo_stroke (cr);
}
cairo_pop_group_to_source (cr);
cairo_paint (cr);
}
static cairo_test_status_t
draw (cairo_t *cr, int width, int height)
{
cairo_pattern_t *blue;
cairo_pattern_t *red;
blue = cairo_pattern_create_rgba (0.0, 0.0, 1.0, 0.8);
red = cairo_pattern_create_rgba (1.0, 0.0, 0.0, 0.2);
cairo_test_paint_checkered (cr);
fill_and_stroke (cr, rectangle, blue, red);
cairo_translate (cr, SIZE + 2 * PAD, 0);
fill_and_stroke (cr, circle, red, blue);
cairo_pattern_destroy (blue);
cairo_pattern_destroy (red);
return CAIRO_TEST_SUCCESS;
}
int
main (void)
{
return cairo_test (&test);
}
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