cairo/test/operator-alpha.c

   1 /*
   2  * Copyright © 2008 Chris Wilson
   3  *
   4  * Permission to use, copy, modify, distribute, and sell this software
   5  * and its documentation for any purpose is hereby granted without
   6  * fee, provided that the above copyright notice appear in all copies
   7  * and that both that copyright notice and this permission notice
   8  * appear in supporting documentation, and that the name of
   9  * Chris Wilson not be used in advertising or publicity pertaining to
  10  * distribution of the software without specific, written prior
  11  * permission. Chris Wilson makes no representations about the
  12  * suitability of this software for any purpose.  It is provided "as
  13  * is" without express or implied warranty.
  14  *
  15  * CHRIS WILSON DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS
  16  * SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
  17  * FITNESS, IN NO EVENT SHALL CHRIS WILSON BE LIABLE FOR ANY SPECIAL,
  18  * INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER
  19  * RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
  20  * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR
  21  * IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  22  *
  23  * Author: Chris Wilson <chris@chris-wilson.co.uk>
  24  */
  25
  26 #include "cairo-test.h"
  27
  28 #define N_OPERATORS (CAIRO_OPERATOR_SATURATE + 1)
  29 #define SIZE 10
  30 #define PAD 3
  31
  32 static cairo_test_draw_function_t draw;
  33
  34 static const cairo_test_t test = {
  35     "operator-alpha",
  36     "Tests using set_operator() with an non-opaque source",
  37     (SIZE+PAD) * N_OPERATORS + PAD, SIZE + 2*PAD,
  38     draw
  39 };
  40
  41 static cairo_test_status_t
  42 draw (cairo_t *cr, int width, int height)
  43 {
  44     unsigned int n;
  45
  46     cairo_translate (cr, PAD, PAD);
  47
  48     for (n = 0; n < N_OPERATORS; n++) {
  49         cairo_reset_clip (cr);
  50         cairo_rectangle (cr, 0, 0, SIZE, SIZE);
  51         cairo_clip (cr);
  52
  53         cairo_set_source_rgb (cr, 1, 0, 0);
  54         cairo_set_operator (cr, CAIRO_OPERATOR_OVER);
  55         cairo_rectangle (cr, 0, 0, SIZE-PAD, SIZE-PAD);
  56         cairo_fill (cr);
  57
  58         cairo_set_source_rgba (cr, 0, 0, 1, .33);
  59         cairo_set_operator (cr, n);
  60         cairo_rectangle (cr, PAD, PAD, SIZE-PAD, SIZE-PAD);
  61         cairo_fill (cr);
  62
  63         cairo_translate (cr, SIZE+PAD, 0);
  64     }
  65
  66     return CAIRO_TEST_SUCCESS;
  67 }
  68
  69 int
  70 main (void)
  71 {
  72     return cairo_test (&test);
  73 }
  74