1 /*
2 * Copyright © 2011 Google, Inc.
3 *
4 * This is part of HarfBuzz, a text shaping library.
5 *
6 * Permission is hereby granted, without written agreement and without
7 * license or royalty fees, to use, copy, modify, and distribute this
8 * software and its documentation for any purpose, provided that the
9 * above copyright notice and the following two paragraphs appear in
10 * all copies of this software.
11 *
12 * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
13 * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
14 * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
15 * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
16 * DAMAGE.
17 *
18 * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
19 * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
20 * FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS
21 * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
22 * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
23 *
24 * Google Author(s): Behdad Esfahbod
25 */
26
27 #include "view-cairo.hh"
28
29 void
get_surface_size(cairo_scaled_font_t * scaled_font,double * w,double * h)30 view_cairo_t::get_surface_size (cairo_scaled_font_t *scaled_font,
31 double *w, double *h)
32 {
33 cairo_font_extents_t font_extents;
34
35 cairo_scaled_font_extents (scaled_font, &font_extents);
36
37 bool vertical = HB_DIRECTION_IS_VERTICAL (direction);
38 (vertical ? *w : *h) = (int) lines->len * (font_extents.height + view_options.line_space) - view_options.line_space;
39 (vertical ? *h : *w) = 0;
40 for (unsigned int i = 0; i < lines->len; i++) {
41 helper_cairo_line_t &line = g_array_index (lines, helper_cairo_line_t, i);
42 double x_advance, y_advance;
43 line.get_advance (&x_advance, &y_advance);
44 if (vertical)
45 *h = MAX (*h, y_advance);
46 else
47 *w = MAX (*w, x_advance);
48 }
49
50 *w += view_options.margin.l + view_options.margin.r;
51 *h += view_options.margin.t + view_options.margin.b;
52 }
53
54 void
render(const font_options_t * font_opts)55 view_cairo_t::render (const font_options_t *font_opts)
56 {
57 cairo_scaled_font_t *scaled_font = helper_cairo_create_scaled_font (font_opts, view_options.font_size);
58 double w, h;
59 get_surface_size (scaled_font, &w, &h);
60 cairo_t *cr = helper_cairo_create_context (w, h, &view_options, &output_options);
61 cairo_set_scaled_font (cr, scaled_font);
62 cairo_scaled_font_destroy (scaled_font);
63
64 draw (cr);
65
66 helper_cairo_destroy_context (cr);
67 }
68
69 void
draw(cairo_t * cr)70 view_cairo_t::draw (cairo_t *cr)
71 {
72 cairo_save (cr);
73
74 bool vertical = HB_DIRECTION_IS_VERTICAL (direction);
75 int v = vertical ? 1 : 0;
76 int h = vertical ? 0 : 1;
77 cairo_font_extents_t font_extents;
78 cairo_font_extents (cr, &font_extents);
79 cairo_translate (cr, view_options.margin.l, view_options.margin.t);
80 double descent;
81 if (vertical)
82 descent = font_extents.height * (lines->len + .5);
83 else
84 descent = font_extents.height - font_extents.ascent;
85 cairo_translate (cr, v * descent, h * -descent);
86 for (unsigned int i = 0; i < lines->len; i++)
87 {
88 helper_cairo_line_t &l = g_array_index (lines, helper_cairo_line_t, i);
89
90 if (i)
91 cairo_translate (cr, v * -view_options.line_space, h * view_options.line_space);
92
93 cairo_translate (cr, v * -font_extents.height, h * font_extents.height);
94
95 if (view_options.annotate) {
96 cairo_save (cr);
97
98 /* Draw actual glyph origins */
99 cairo_set_source_rgba (cr, 1., 0., 0., .5);
100 cairo_set_line_width (cr, 5);
101 cairo_set_line_cap (cr, CAIRO_LINE_CAP_ROUND);
102 for (unsigned i = 0; i < l.num_glyphs; i++) {
103 cairo_move_to (cr, l.glyphs[i].x, l.glyphs[i].y);
104 cairo_rel_line_to (cr, 0, 0);
105 }
106 cairo_stroke (cr);
107
108 cairo_restore (cr);
109 }
110
111 if (0 && cairo_surface_get_type (cairo_get_target (cr)) == CAIRO_SURFACE_TYPE_IMAGE) {
112 /* cairo_show_glyphs() doesn't support subpixel positioning */
113 cairo_glyph_path (cr, l.glyphs, l.num_glyphs);
114 cairo_fill (cr);
115 } else if (l.num_clusters)
116 cairo_show_text_glyphs (cr,
117 l.utf8, l.utf8_len,
118 l.glyphs, l.num_glyphs,
119 l.clusters, l.num_clusters,
120 l.cluster_flags);
121 else
122 cairo_show_glyphs (cr, l.glyphs, l.num_glyphs);
123 }
124
125 cairo_restore (cr);
126 }
127