1/*
2 * Copyright © 2022 Matthias Clasen
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
25#ifndef HB_PAINT_HH
26#define HB_PAINT_HH
27
28#include "hb.hh"
29#include "hb-face.hh"
30#include "hb-font.hh"
31
32#define HB_PAINT_FUNCS_IMPLEMENT_CALLBACKS \
33 HB_PAINT_FUNC_IMPLEMENT (push_transform) \
34 HB_PAINT_FUNC_IMPLEMENT (pop_transform) \
35 HB_PAINT_FUNC_IMPLEMENT (push_clip_glyph) \
36 HB_PAINT_FUNC_IMPLEMENT (push_clip_rectangle) \
37 HB_PAINT_FUNC_IMPLEMENT (pop_clip) \
38 HB_PAINT_FUNC_IMPLEMENT (color) \
39 HB_PAINT_FUNC_IMPLEMENT (image) \
40 HB_PAINT_FUNC_IMPLEMENT (linear_gradient) \
41 HB_PAINT_FUNC_IMPLEMENT (radial_gradient) \
42 HB_PAINT_FUNC_IMPLEMENT (sweep_gradient) \
43 HB_PAINT_FUNC_IMPLEMENT (push_group) \
44 HB_PAINT_FUNC_IMPLEMENT (pop_group) \
45 HB_PAINT_FUNC_IMPLEMENT (custom_palette_color) \
46 /* ^--- Add new callbacks here */
47
48struct hb_paint_funcs_t
49{
50 hb_object_header_t header;
51
52 struct {
53#define HB_PAINT_FUNC_IMPLEMENT(name) hb_paint_##name##_func_t name;
54 HB_PAINT_FUNCS_IMPLEMENT_CALLBACKS
55#undef HB_PAINT_FUNC_IMPLEMENT
56 } func;
57
58 struct {
59#define HB_PAINT_FUNC_IMPLEMENT(name) void *name;
60 HB_PAINT_FUNCS_IMPLEMENT_CALLBACKS
61#undef HB_PAINT_FUNC_IMPLEMENT
62 } *user_data;
63
64 struct {
65#define HB_PAINT_FUNC_IMPLEMENT(name) hb_destroy_func_t name;
66 HB_PAINT_FUNCS_IMPLEMENT_CALLBACKS
67#undef HB_PAINT_FUNC_IMPLEMENT
68 } *destroy;
69
70 void push_transform (void *paint_data,
71 float xx, float yx,
72 float xy, float yy,
73 float dx, float dy)
74 { func.push_transform (this, paint_data,
75 xx, yx, xy, yy, dx, dy,
76 !user_data ? nullptr : user_data->push_transform); }
77 void pop_transform (void *paint_data)
78 { func.pop_transform (this, paint_data,
79 !user_data ? nullptr : user_data->pop_transform); }
80 void push_clip_glyph (void *paint_data,
81 hb_codepoint_t glyph,
82 hb_font_t *font)
83 { func.push_clip_glyph (this, paint_data,
84 glyph,
85 font,
86 !user_data ? nullptr : user_data->push_clip_glyph); }
87 void push_clip_rectangle (void *paint_data,
88 float xmin, float ymin, float xmax, float ymax)
89 { func.push_clip_rectangle (this, paint_data,
90 xmin, ymin, xmax, ymax,
91 !user_data ? nullptr : user_data->push_clip_rectangle); }
92 void pop_clip (void *paint_data)
93 { func.pop_clip (this, paint_data,
94 !user_data ? nullptr : user_data->pop_clip); }
95 void color (void *paint_data,
96 hb_bool_t is_foreground,
97 hb_color_t color)
98 { func.color (this, paint_data,
99 is_foreground, color,
100 !user_data ? nullptr : user_data->color); }
101 bool image (void *paint_data,
102 hb_blob_t *image,
103 unsigned width, unsigned height,
104 hb_tag_t format,
105 float slant,
106 hb_glyph_extents_t *extents)
107 { return func.image (this, paint_data,
108 image, width, height, format, slant, extents,
109 !user_data ? nullptr : user_data->image); }
110 void linear_gradient (void *paint_data,
111 hb_color_line_t *color_line,
112 float x0, float y0,
113 float x1, float y1,
114 float x2, float y2)
115 { func.linear_gradient (this, paint_data,
116 color_line, x0, y0, x1, y1, x2, y2,
117 !user_data ? nullptr : user_data->linear_gradient); }
118 void radial_gradient (void *paint_data,
119 hb_color_line_t *color_line,
120 float x0, float y0, float r0,
121 float x1, float y1, float r1)
122 { func.radial_gradient (this, paint_data,
123 color_line, x0, y0, r0, x1, y1, r1,
124 !user_data ? nullptr : user_data->radial_gradient); }
125 void sweep_gradient (void *paint_data,
126 hb_color_line_t *color_line,
127 float x0, float y0,
128 float start_angle,
129 float end_angle)
130 { func.sweep_gradient (this, paint_data,
131 color_line, x0, y0, start_angle, end_angle,
132 !user_data ? nullptr : user_data->sweep_gradient); }
133 void push_group (void *paint_data)
134 { func.push_group (this, paint_data,
135 !user_data ? nullptr : user_data->push_group); }
136 void pop_group (void *paint_data,
137 hb_paint_composite_mode_t mode)
138 { func.pop_group (this, paint_data,
139 mode,
140 !user_data ? nullptr : user_data->pop_group); }
141 bool custom_palette_color (void *paint_data,
142 unsigned int color_index,
143 hb_color_t *color)
144 { return func.custom_palette_color (this, paint_data,
145 color_index,
146 color,
147 !user_data ? nullptr : user_data->custom_palette_color); }
148
149
150 /* Internal specializations. */
151
152 void push_root_transform (void *paint_data,
153 const hb_font_t *font)
154 {
155 float upem = font->face->get_upem ();
156 int xscale = font->x_scale, yscale = font->y_scale;
157 float slant = font->slant_xy;
158
159 push_transform (paint_data,
160 xscale/upem, 0, slant * yscale/upem, yscale/upem, 0, 0);
161 }
162
163 void push_inverse_root_transform (void *paint_data,
164 hb_font_t *font)
165 {
166 float upem = font->face->get_upem ();
167 int xscale = font->x_scale ? font->x_scale : upem;
168 int yscale = font->y_scale ? font->y_scale : upem;
169 float slant = font->slant_xy;
170
171 push_transform (paint_data,
172 upem/xscale, 0, -slant * upem/xscale, upem/yscale, 0, 0);
173 }
174
175 HB_NODISCARD
176 bool push_translate (void *paint_data,
177 float dx, float dy)
178 {
179 if (!dx && !dy)
180 return false;
181
182 push_transform (paint_data,
183 1.f, 0.f, 0.f, 1.f, dx, dy);
184 return true;
185 }
186
187 HB_NODISCARD
188 bool push_scale (void *paint_data,
189 float sx, float sy)
190 {
191 if (sx == 1.f && sy == 1.f)
192 return false;
193
194 push_transform (paint_data,
195 sx, 0.f, 0.f, sy, 0.f, 0.f);
196 return true;
197 }
198
199 HB_NODISCARD
200 bool push_rotate (void *paint_data,
201 float a)
202 {
203 if (!a)
204 return false;
205
206 float cc = cosf (a * HB_PI);
207 float ss = sinf (a * HB_PI);
208 push_transform (paint_data, cc, ss, -ss, cc, 0.f, 0.f);
209 return true;
210 }
211
212 HB_NODISCARD
213 bool push_skew (void *paint_data,
214 float sx, float sy)
215 {
216 if (!sx && !sy)
217 return false;
218
219 float x = tanf (-sx * HB_PI);
220 float y = tanf (+sy * HB_PI);
221 push_transform (paint_data, 1.f, y, x, 1.f, 0.f, 0.f);
222 return true;
223 }
224};
225DECLARE_NULL_INSTANCE (hb_paint_funcs_t);
226
227
228#endif /* HB_PAINT_HH */
229