text-pattern.c

按照官方的说法：Cairo is a vector graphics library with cross-device output support. 翻译过来

/*
 * Copyright © 2005 Tim Rowley
 *
 * 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: Tim Rowley
 */

#include "cairo-test.h"

#define IMAGE_WIDTH 64
#define IMAGE_HEIGHT 64

cairo_test_t test = {
    "text-pattern",
    "Patterned Text",
    IMAGE_WIDTH, IMAGE_HEIGHT
};

static cairo_test_status_t
draw (cairo_t *cr, int width, int height)
{
  cairo_font_options_t *font_options;
  cairo_pattern_t *pat;

  font_options = cairo_font_options_create ();

  cairo_font_options_set_hint_style (font_options, CAIRO_HINT_STYLE_NONE);
  cairo_font_options_set_antialias (font_options, CAIRO_ANTIALIAS_GRAY);

  cairo_set_font_options (cr, font_options);
  cairo_font_options_destroy (font_options);

  cairo_select_font_face (cr, "Bitstream Vera Sans",
			  CAIRO_FONT_SLANT_NORMAL,
			  CAIRO_FONT_WEIGHT_NORMAL);

  cairo_scale (cr, width, height);

  pat = cairo_pattern_create_linear (0.0, 0.0, 1, 1);
  cairo_pattern_add_color_stop_rgba (pat, 1, 1, 0, 0, 1);
  cairo_pattern_add_color_stop_rgba (pat, 0, 0, 0, 1, 1);
  cairo_set_source (cr, pat);

  /* test rectangle - make sure the gradient is set correctly */
  cairo_rectangle (cr, 0, 0, 0.1, 1);
  cairo_fill (cr);

  cairo_set_font_size (cr, 0.4);
  cairo_move_to (cr, 0.1, 0.6);
  cairo_show_text (cr, "cairo");

  cairo_pattern_destroy (pat);

  return CAIRO_TEST_SUCCESS;
}

int
main (void)
{
    return cairo_test (&test, draw);
}