cairo/test/text-glyph-range.c

   1 /* -*- Mode: c; c-basic-offset: 4; tab-width: 8; indent-tabs-mode: t; -*- */
   2 /* cairo - a vector graphics library with display and print output
   3  *
   4  * Copyright © 2006 Brian Ewins.
   5  *
   6  * Permission to use, copy, modify, distribute, and sell this software
   7  * and its documentation for any purpose is hereby granted without
   8  * fee, provided that the above copyright notice appear in all copies
   9  * and that both that copyright notice and this permission notice
  10  * appear in supporting documentation, and that the name of
  11  * Brian Ewins not be used in advertising or publicity pertaining to
  12  * distribution of the software without specific, written prior
  13  * permission. Brian Ewins makes no representations about the
  14  * suitability of this software for any purpose.  It is provided "as
  15  * is" without express or implied warranty.
  16  *
  17  * BRIAN EWINS DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS
  18  * SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
  19  * FITNESS, IN NO EVENT SHALL BRIAN EWINS BE LIABLE FOR ANY SPECIAL,
  20  * INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER
  21  * RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
  22  * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR
  23  * IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  24  *
  25  * Author: Brian Ewins <Brian.Ewins@gmail.com>
  26  */
  27
  28 /* Related to bug 9530
  29  *
  30  * cairo_glyph_t can contain any unsigned long in its 'index', the intention
  31  * being that it is large enough to hold a pointer. However, this means that
  32  * it can specify many glyph indexes which don't exist in the font, and may
  33  * exceed the range of legal glyph indexes for the font backend. It may
  34  * also contain special values that are not usable as indexes - e.g. 0xffff is
  35  * kATSDeletedGlyphcode in ATSUI, a glyph that should not be drawn.
  36  * The font backends should handle all legal and out-of-range values consistently.
  37  *
  38  * This test expects that operations on out-of-range and missing glyphs should
  39  * act as if they were zero-width.
  40  */
  41
  42 #include "cairo-test.h"
  43
  44 #define WIDTH  100
  45 #define HEIGHT 75
  46 #define NUM_TEXT 20
  47 #define TEXT_SIZE 12
  48
  49 static cairo_test_draw_function_t draw;
  50
  51 cairo_test_t test = {
  52     "text-glyph-range",
  53     "Tests show_glyphs, glyph_path, glyph_extents with out of range glyph ids."
  54     "\nft and atsui font backends fail, misreporting errors from FT_Load_Glyph and ATSUGlyphGetCubicPaths",
  55     WIDTH, HEIGHT,
  56     draw
  57 };
  58
  59 static cairo_test_status_t
  60 draw (cairo_t *cr, int width, int height)
  61 {
  62     cairo_text_extents_t extents;
  63     int i;
  64     /* Glyphs with no paths followed by 'cairo', the additional
  65      * text is to make the space obvious.
  66      */
  67     long int index[] = {
  68         0, /* 'no matching glyph' */
  69         0xffff, /* kATSDeletedGlyphCode */
  70         0x1ffff, /* out of range */
  71         -1L, /* out of range */
  72         70, 68, 76, 85, 82 /* 'cairo' */
  73     };
  74
  75     /* We draw in the default black, so paint white first. */
  76     cairo_save (cr);
  77     cairo_set_source_rgb (cr, 1.0, 1.0, 1.0); /* white */
  78     cairo_paint (cr);
  79     cairo_restore (cr);
  80
  81     cairo_select_font_face (cr, "Bitstream Vera Sans",
  82                             CAIRO_FONT_SLANT_NORMAL,
  83                             CAIRO_FONT_WEIGHT_NORMAL);
  84     cairo_set_font_size (cr, 16);
  85
  86
  87     for (i = 0; i < 9; i++) {
  88         /* since we're just drawing glyphs directly we need to position them. */
  89         cairo_glyph_t glyph = {
  90             index[i], 10 * i, 25
  91         };
  92
  93         /* test cairo_glyph_extents. Every glyph index should
  94          * have extents, invalid glyphs should be zero-width.
  95          */
  96         cairo_move_to (cr, glyph.x, glyph.y);
  97         cairo_set_line_width (cr, 1.0);
  98         cairo_glyph_extents (cr, &glyph, 1, &extents);
  99         cairo_rectangle (cr,
 100                          glyph.x + extents.x_bearing - 0.5,
 101                          glyph.y + extents.y_bearing - 0.5,
 102                          extents.width + 1,
 103                          extents.height + 1);
 104         cairo_set_source_rgb (cr, 1, 0, 0); /* red */
 105         cairo_stroke (cr);
 106
 107         /* test cairo_show_glyphs. Every glyph index should be
 108          * drawable, invalid glyph indexes should draw nothing.
 109          */
 110         cairo_set_source_rgb (cr, 0, 0, 0); /* black */
 111         cairo_show_glyphs (cr, &glyph, 1);
 112         cairo_move_to (cr, glyph.x, glyph.y);
 113
 114         /* test cairo_glyph_path. Every glyph index should produce
 115          * a path, invalid glyph indexes should have empty paths.
 116          */
 117         /* Change the glyph position
 118          * so that the paths are visible.
 119          */
 120         glyph.y = 55;
 121         cairo_move_to (cr, glyph.x, glyph.y);
 122         cairo_glyph_path (cr, &glyph, 1);
 123         cairo_fill (cr);
 124     }
 125
 126     return CAIRO_TEST_SUCCESS;
 127 }
 128
 129 int
 130 main (void)
 131 {
 132     return cairo_test (&test);
 133 }