test/glyph-cache-pressure.c

   1 /*
   2  * Copyright © 2005 Red Hat, Inc.
   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  * Red Hat, Inc. not be used in advertising or publicity pertaining to
  10  * distribution of the software without specific, written prior
  11  * permission. Red Hat, Inc. 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  * RED HAT, INC. DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS
  16  * SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
  17  * FITNESS, IN NO EVENT SHALL RED HAT, INC. 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: Carl D. Worth <cworth@cworth.org>
  24  */
  25
  26 #include "cairo-test.h"
  27 #include "cairo-boilerplate-scaled-font.h"
  28
  29 #define TEXT_SIZE 12
  30
  31 /* Bug history
  32  *
  33  * 2006-06-22  Carl Worth  <cworth@cworth.org>
  34  *
  35  *   This is a test case to demonstrate the following bug in the xlib backend:
  36  *
  37  *      Some characters aren't displayed when using xlib (cache usage missing freeze/thaw)
  38  *      https://bugs.freedesktop.org/show_bug.cgi?id=6955
  39  *
  40  *   We replicate this bug by using the cairo_scaled_font_set_max_glyphs_per_font
  41  *   function to artifically induce cache pressure. (This function was added
  42  *   for this very purpose.)
  43  *
  44  * 2006-06-22  Carl Worth  <cworth@cworth.org>
  45  *
  46  *   Bug was simple enough to solve by just adding a freeze/thaw pair
  47  *   around the scaled_font's glyph cache in
  48  *   _cairo_xlib_surface_show_glyphs, (I went ahead and added
  49  *   _cairo_sacled_font_freeze/thaw_cache functions for this).
  50  */
  51
  52 static cairo_test_draw_function_t draw;
  53
  54 cairo_test_t test = {
  55     "glyph-cache-pressure",
  56     "Ensure that all backends behave well under artificial glyph cache pressure",
  57     223, TEXT_SIZE + 4,
  58     draw
  59 };
  60
  61 static cairo_test_status_t
  62 draw (cairo_t *cr, int width, int height)
  63 {
  64     /* We draw in the default black, so paint white first. */
  65     cairo_save (cr);
  66     cairo_set_source_rgb (cr, 1.0, 1.0, 1.0); /* white */
  67     cairo_paint (cr);
  68     cairo_restore (cr);
  69
  70     cairo_select_font_face (cr, "Bitstream Vera Sans",
  71                             CAIRO_FONT_SLANT_NORMAL,
  72                             CAIRO_FONT_WEIGHT_NORMAL);
  73     cairo_set_font_size (cr, TEXT_SIZE);
  74
  75     cairo_set_source_rgb (cr, 0, 0, 0); /* black */
  76
  77     cairo_boilerplate_scaled_font_set_max_glyphs_cached (cairo_get_scaled_font (cr), 1);
  78
  79     cairo_move_to (cr, 1, TEXT_SIZE);
  80     cairo_show_text (cr, "the five boxing wizards jump quickly");
  81
  82     return CAIRO_TEST_SUCCESS;
  83 }
  84
  85 int
  86 main (void)
  87 {
  88     return cairo_test (&test);
  89 }