test/font-matrix-translation.c

   1 /*
   2  * Copyright © 2006 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
  28 #define TEXT_SIZE 12
  29 #define PAD 4
  30 #define TEXT "text"
  31
  32 static cairo_bool_t
  33 text_extents_equal (const cairo_text_extents_t *A,
  34                     const cairo_text_extents_t *B)
  35 {
  36     return A->x_bearing == B->x_bearing &&
  37            A->y_bearing == B->y_bearing &&
  38            A->width     == B->width     &&
  39            A->height    == B->height    &&
  40            A->x_advance == B->x_advance &&
  41            A->y_advance == B->y_advance;
  42 }
  43
  44 static cairo_test_status_t
  45 box_text (const cairo_test_context_t *ctx, cairo_t *cr,
  46           const char *utf8,
  47           double x, double y)
  48 {
  49     double line_width;
  50     cairo_text_extents_t extents = {0}, scaled_extents = {0};
  51     cairo_scaled_font_t *scaled_font;
  52     cairo_status_t status;
  53
  54     cairo_save (cr);
  55
  56     cairo_text_extents (cr, utf8, &extents);
  57
  58     scaled_font = cairo_get_scaled_font (cr);
  59     cairo_scaled_font_text_extents (scaled_font, TEXT, &scaled_extents);
  60     status = cairo_scaled_font_status (scaled_font);
  61     if (status)
  62         return cairo_test_status_from_status (ctx, status);
  63
  64     if (! text_extents_equal (&extents, &scaled_extents)) {
  65         cairo_test_log (ctx,
  66                         "Error: extents differ when they shouldn't:\n"
  67                         "cairo_text_extents(); extents (%g, %g, %g, %g, %g, %g)\n"
  68                         "cairo_scaled_font_text_extents(); extents (%g, %g, %g, %g, %g, %g)\n",
  69                         extents.x_bearing, extents.y_bearing,
  70                         extents.width, extents.height,
  71                         extents.x_advance, extents.y_advance,
  72                         scaled_extents.x_bearing, scaled_extents.y_bearing,
  73                         scaled_extents.width, scaled_extents.height,
  74                         scaled_extents.x_advance, scaled_extents.y_advance);
  75         return CAIRO_TEST_FAILURE;
  76     }
  77
  78     line_width = cairo_get_line_width (cr);
  79     cairo_rectangle (cr,
  80                      x + extents.x_bearing - line_width / 2,
  81                      y + extents.y_bearing - line_width / 2,
  82                      extents.width  + line_width,
  83                      extents.height + line_width);
  84     cairo_stroke (cr);
  85
  86     cairo_move_to (cr, x, y);
  87     cairo_show_text (cr, utf8);
  88
  89     cairo_restore (cr);
  90
  91     return CAIRO_TEST_SUCCESS;
  92 }
  93
  94 static cairo_test_status_t
  95 draw (cairo_t *cr, int width, int height)
  96 {
  97     const cairo_test_context_t *ctx = cairo_test_get_context (cr);
  98     cairo_test_status_t status;
  99     cairo_text_extents_t extents;
 100     cairo_matrix_t matrix;
 101
 102     cairo_set_source_rgb (cr, 1.0, 1.0, 1.0); /* white */
 103     cairo_paint (cr);
 104
 105     cairo_select_font_face (cr, "Bitstream Vera Sans",
 106                             CAIRO_FONT_SLANT_NORMAL,
 107                             CAIRO_FONT_WEIGHT_NORMAL);
 108     cairo_set_font_size (cr, TEXT_SIZE);
 109
 110     cairo_translate (cr, PAD, PAD);
 111     cairo_set_line_width (cr, 1.0);
 112
 113     cairo_text_extents (cr, TEXT, &extents);
 114
 115     /* Draw text and bounding box */
 116     cairo_set_source_rgb (cr, 0, 0, 0); /* black */
 117     status = box_text (ctx, cr, TEXT, 0, - extents.y_bearing);
 118     if (status)
 119         return status;
 120
 121     /* Then draw again with the same coordinates, but with a font
 122      * matrix to position the text below and shifted a bit to the
 123      * right. */
 124     cairo_matrix_init_translate (&matrix, TEXT_SIZE / 2, TEXT_SIZE + PAD);
 125     cairo_matrix_scale (&matrix, TEXT_SIZE, TEXT_SIZE);
 126     cairo_set_font_matrix (cr, &matrix);
 127
 128     cairo_set_source_rgb (cr, 0, 0, 1); /* blue */
 129     status = box_text (ctx, cr, TEXT, 0, - extents.y_bearing);
 130     if (status)
 131         return status;
 132
 133     return CAIRO_TEST_SUCCESS;
 134 }
 135
 136 CAIRO_TEST (font_matrix_translation,
 137             "Test that translation in a font matrix can be used to offset a string",
 138             "font", /* keywords */
 139             NULL, /* requirements */
 140             38, 34,
 141             NULL, draw)