1 /****************************************************************************
2 *
3 * ftrender.h
4 *
5 * FreeType renderer modules public interface (specification).
6 *
7 * Copyright (C) 1996-2019 by
8 * David Turner, Robert Wilhelm, and Werner Lemberg.
9 *
10 * This file is part of the FreeType project, and may only be used,
11 * modified, and distributed under the terms of the FreeType project
12 * license, LICENSE.TXT. By continuing to use, modify, or distribute
13 * this file you indicate that you have read the license and
14 * understand and accept it fully.
15 *
16 */
17
18
19 #ifndef FTRENDER_H_
20 #define FTRENDER_H_
21
22
23 #include <ft2build.h>
24 #include FT_MODULE_H
25 #include FT_GLYPH_H
26
27
28 FT_BEGIN_HEADER
29
30
31 /**************************************************************************
32 *
33 * @section:
34 * module_management
35 *
36 */
37
38
39 /* create a new glyph object */
40 typedef FT_Error
41 (*FT_Glyph_InitFunc)( FT_Glyph glyph,
42 FT_GlyphSlot slot );
43
44 /* destroys a given glyph object */
45 typedef void
46 (*FT_Glyph_DoneFunc)( FT_Glyph glyph );
47
48 typedef void
49 (*FT_Glyph_TransformFunc)( FT_Glyph glyph,
50 const FT_Matrix* matrix,
51 const FT_Vector* delta );
52
53 typedef void
54 (*FT_Glyph_GetBBoxFunc)( FT_Glyph glyph,
55 FT_BBox* abbox );
56
57 typedef FT_Error
58 (*FT_Glyph_CopyFunc)( FT_Glyph source,
59 FT_Glyph target );
60
61 typedef FT_Error
62 (*FT_Glyph_PrepareFunc)( FT_Glyph glyph,
63 FT_GlyphSlot slot );
64
65 /* deprecated */
66 #define FT_Glyph_Init_Func FT_Glyph_InitFunc
67 #define FT_Glyph_Done_Func FT_Glyph_DoneFunc
68 #define FT_Glyph_Transform_Func FT_Glyph_TransformFunc
69 #define FT_Glyph_BBox_Func FT_Glyph_GetBBoxFunc
70 #define FT_Glyph_Copy_Func FT_Glyph_CopyFunc
71 #define FT_Glyph_Prepare_Func FT_Glyph_PrepareFunc
72
73
74 struct FT_Glyph_Class_
75 {
76 FT_Long glyph_size;
77 FT_Glyph_Format glyph_format;
78
79 FT_Glyph_InitFunc glyph_init;
80 FT_Glyph_DoneFunc glyph_done;
81 FT_Glyph_CopyFunc glyph_copy;
82 FT_Glyph_TransformFunc glyph_transform;
83 FT_Glyph_GetBBoxFunc glyph_bbox;
84 FT_Glyph_PrepareFunc glyph_prepare;
85 };
86
87
88 typedef FT_Error
89 (*FT_Renderer_RenderFunc)( FT_Renderer renderer,
90 FT_GlyphSlot slot,
91 FT_Render_Mode mode,
92 const FT_Vector* origin );
93
94 typedef FT_Error
95 (*FT_Renderer_TransformFunc)( FT_Renderer renderer,
96 FT_GlyphSlot slot,
97 const FT_Matrix* matrix,
98 const FT_Vector* delta );
99
100
101 typedef void
102 (*FT_Renderer_GetCBoxFunc)( FT_Renderer renderer,
103 FT_GlyphSlot slot,
104 FT_BBox* cbox );
105
106
107 typedef FT_Error
108 (*FT_Renderer_SetModeFunc)( FT_Renderer renderer,
109 FT_ULong mode_tag,
110 FT_Pointer mode_ptr );
111
112 /* deprecated identifiers */
113 #define FTRenderer_render FT_Renderer_RenderFunc
114 #define FTRenderer_transform FT_Renderer_TransformFunc
115 #define FTRenderer_getCBox FT_Renderer_GetCBoxFunc
116 #define FTRenderer_setMode FT_Renderer_SetModeFunc
117
118
119 /**************************************************************************
120 *
121 * @struct:
122 * FT_Renderer_Class
123 *
124 * @description:
125 * The renderer module class descriptor.
126 *
127 * @fields:
128 * root ::
129 * The root @FT_Module_Class fields.
130 *
131 * glyph_format ::
132 * The glyph image format this renderer handles.
133 *
134 * render_glyph ::
135 * A method used to render the image that is in a given glyph slot into
136 * a bitmap.
137 *
138 * transform_glyph ::
139 * A method used to transform the image that is in a given glyph slot.
140 *
141 * get_glyph_cbox ::
142 * A method used to access the glyph's cbox.
143 *
144 * set_mode ::
145 * A method used to pass additional parameters.
146 *
147 * raster_class ::
148 * For @FT_GLYPH_FORMAT_OUTLINE renderers only. This is a pointer to
149 * its raster's class.
150 */
151 typedef struct FT_Renderer_Class_
152 {
153 FT_Module_Class root;
154
155 FT_Glyph_Format glyph_format;
156
157 FT_Renderer_RenderFunc render_glyph;
158 FT_Renderer_TransformFunc transform_glyph;
159 FT_Renderer_GetCBoxFunc get_glyph_cbox;
160 FT_Renderer_SetModeFunc set_mode;
161
162 FT_Raster_Funcs* raster_class;
163
164 } FT_Renderer_Class;
165
166
167 /**************************************************************************
168 *
169 * @function:
170 * FT_Get_Renderer
171 *
172 * @description:
173 * Retrieve the current renderer for a given glyph format.
174 *
175 * @input:
176 * library ::
177 * A handle to the library object.
178 *
179 * format ::
180 * The glyph format.
181 *
182 * @return:
183 * A renderer handle. 0~if none found.
184 *
185 * @note:
186 * An error will be returned if a module already exists by that name, or
187 * if the module requires a version of FreeType that is too great.
188 *
189 * To add a new renderer, simply use @FT_Add_Module. To retrieve a
190 * renderer by its name, use @FT_Get_Module.
191 */
192 FT_EXPORT( FT_Renderer )
193 FT_Get_Renderer( FT_Library library,
194 FT_Glyph_Format format );
195
196
197 /**************************************************************************
198 *
199 * @function:
200 * FT_Set_Renderer
201 *
202 * @description:
203 * Set the current renderer to use, and set additional mode.
204 *
205 * @inout:
206 * library ::
207 * A handle to the library object.
208 *
209 * @input:
210 * renderer ::
211 * A handle to the renderer object.
212 *
213 * num_params ::
214 * The number of additional parameters.
215 *
216 * parameters ::
217 * Additional parameters.
218 *
219 * @return:
220 * FreeType error code. 0~means success.
221 *
222 * @note:
223 * In case of success, the renderer will be used to convert glyph images
224 * in the renderer's known format into bitmaps.
225 *
226 * This doesn't change the current renderer for other formats.
227 *
228 * Currently, no FreeType renderer module uses `parameters`; you should
229 * thus always pass `NULL` as the value.
230 */
231 FT_EXPORT( FT_Error )
232 FT_Set_Renderer( FT_Library library,
233 FT_Renderer renderer,
234 FT_UInt num_params,
235 FT_Parameter* parameters );
236
237 /* */
238
239
240 FT_END_HEADER
241
242 #endif /* FTRENDER_H_ */
243
244
245 /* END */