libass/ass_render.h

   1 /*
   2  * Copyright (C) 2006 Evgeniy Stepanov <eugeni.stepanov@gmail.com>
   3  * Copyright (C) 2009 Grigori Goronzy <greg@geekmind.org>
   4  *
   5  * This file is part of libass.
   6  *
   7  * libass is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation; either version 2 of the License, or
  10  * (at your option) any later version.
  11  *
  12  * libass is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License along
  18  * with libass; if not, write to the Free Software Foundation, Inc.,
  19  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  20  */
  21
  22 #ifndef LIBASS_RENDER_H
  23 #define LIBASS_RENDER_H
  24
  25 #include <inttypes.h>
  26 #include <ft2build.h>
  27 #include FT_FREETYPE_H
  28 #include FT_STROKER_H
  29 #include FT_GLYPH_H
  30 #include FT_SYNTHESIS_H
  31
  32 #include "ass.h"
  33 #include "ass_font.h"
  34 #include "ass_bitmap.h"
  35 #include "ass_cache.h"
  36 #include "ass_utils.h"
  37 #include "ass_fontconfig.h"
  38 #include "ass_library.h"
  39 #include "ass_drawing.h"
  40
  41 typedef struct {
  42     double xMin;
  43     double xMax;
  44     double yMin;
  45     double yMax;
  46 } DBBox;
  47
  48 typedef struct {
  49     double x;
  50     double y;
  51 } DVector;
  52
  53 typedef struct free_list {
  54     void *object;
  55     struct free_list *next;
  56 } FreeList;
  57
  58 typedef struct {
  59     int frame_width;
  60     int frame_height;
  61     double font_size_coeff;     // font size multiplier
  62     double line_spacing;        // additional line spacing (in frame pixels)
  63     int top_margin;             // height of top margin. Everything except toptitles is shifted down by top_margin.
  64     int bottom_margin;          // height of bottom margin. (frame_height - top_margin - bottom_margin) is original video height.
  65     int left_margin;
  66     int right_margin;
  67     int use_margins;            // 0 - place all subtitles inside original frame
  68     // 1 - use margins for placing toptitles and subtitles
  69     double aspect;              // frame aspect ratio, d_width / d_height.
  70     double storage_aspect;      // pixel ratio of the source image
  71     ASS_Hinting hinting;
  72
  73     char *default_font;
  74     char *default_family;
  75 } ASS_Settings;
  76
  77 // a rendered event
  78 typedef struct {
  79     ASS_Image *imgs;
  80     int top, height, left, width;
  81     int detect_collisions;
  82     int shift_direction;
  83     ASS_Event *event;
  84 } EventImages;
  85
  86 typedef enum {
  87     EF_NONE = 0,
  88     EF_KARAOKE,
  89     EF_KARAOKE_KF,
  90     EF_KARAOKE_KO
  91 } Effect;
  92
  93 // describes a glyph
  94 // GlyphInfo and TextInfo are used for text centering and word-wrapping operations
  95 typedef struct {
  96     unsigned symbol;
  97     unsigned skip;              // skip glyph when layouting text
  98     FT_Glyph glyph;
  99     FT_Glyph outline_glyph;
 100     Bitmap *bm;                 // glyph bitmap
 101     Bitmap *bm_o;               // outline bitmap
 102     Bitmap *bm_s;               // shadow bitmap
 103     FT_BBox bbox;
 104     FT_Vector pos;
 105     char linebreak;             // the first (leading) glyph of some line ?
 106     uint32_t c[4];              // colors
 107     FT_Vector advance;          // 26.6
 108     Effect effect_type;
 109     int effect_timing;          // time duration of current karaoke word
 110     // after process_karaoke_effects: distance in pixels from the glyph origin.
 111     // part of the glyph to the left of it is displayed in a different color.
 112     int effect_skip_timing;     // delay after the end of last karaoke word
 113     int asc, desc;              // font max ascender and descender
 114     int be;                     // blur edges
 115     double blur;                // gaussian blur
 116     double shadow_x;
 117     double shadow_y;
 118     double frx, fry, frz;       // rotation
 119     double fax, fay;            // text shearing
 120
 121     BitmapHashKey hash_key;
 122 } GlyphInfo;
 123
 124 typedef struct {
 125     double asc, desc;
 126 } LineInfo;
 127
 128 typedef struct {
 129     GlyphInfo *glyphs;
 130     int length;
 131     LineInfo *lines;
 132     int n_lines;
 133     double height;
 134     int max_glyphs;
 135     int max_lines;
 136 } TextInfo;
 137
 138 // Renderer state.
 139 // Values like current font face, color, screen position, clipping and so on are stored here.
 140 typedef struct {
 141     ASS_Event *event;
 142     ASS_Style *style;
 143
 144     ASS_Font *font;
 145     char *font_path;
 146     double font_size;
 147     int flags;                  // decoration flags (underline/strike-through)
 148
 149     FT_Stroker stroker;
 150     int alignment;              // alignment overrides go here; if zero, style value will be used
 151     double frx, fry, frz;
 152     double fax, fay;            // text shearing
 153     enum {
 154         EVENT_NORMAL,           // "normal" top-, sub- or mid- title
 155         EVENT_POSITIONED,       // happens after pos(,), margins are ignored
 156         EVENT_HSCROLL,          // "Banner" transition effect, text_width is unlimited
 157         EVENT_VSCROLL           // "Scroll up", "Scroll down" transition effects
 158     } evt_type;
 159     double pos_x, pos_y;        // position
 160     double org_x, org_y;        // origin
 161     char have_origin;           // origin is explicitly defined; if 0, get_base_point() is used
 162     double scale_x, scale_y;
 163     double hspacing;            // distance between letters, in pixels
 164     double border_x;            // outline width
 165     double border_y;
 166     uint32_t c[4];              // colors(Primary, Secondary, so on) in RGBA
 167     int clip_x0, clip_y0, clip_x1, clip_y1;
 168     char clip_mode;             // 1 = iclip
 169     char detect_collisions;
 170     uint32_t fade;              // alpha from \fad
 171     char be;                    // blur edges
 172     double blur;                // gaussian blur
 173     double shadow_x;
 174     double shadow_y;
 175     int drawing_mode;           // not implemented; when != 0 text is discarded, except for style override tags
 176     ASS_Drawing *drawing;       // current drawing
 177     ASS_Drawing *clip_drawing;  // clip vector
 178     int clip_drawing_mode;      // 0 = regular clip, 1 = inverse clip
 179
 180     Effect effect_type;
 181     int effect_timing;
 182     int effect_skip_timing;
 183
 184     enum {
 185         SCROLL_LR,              // left-to-right
 186         SCROLL_RL,
 187         SCROLL_TB,              // top-to-bottom
 188         SCROLL_BT
 189     } scroll_direction;         // for EVENT_HSCROLL, EVENT_VSCROLL
 190     int scroll_shift;
 191
 192     // face properties
 193     char *family;
 194     unsigned bold;
 195     unsigned italic;
 196     int treat_family_as_pattern;
 197     int wrap_style;
 198 } RenderContext;
 199
 200 typedef struct {
 201     Hashmap *font_cache;
 202     Hashmap *glyph_cache;
 203     Hashmap *bitmap_cache;
 204     Hashmap *composite_cache;
 205     size_t glyph_max;
 206     size_t bitmap_max_size;
 207 } CacheStore;
 208
 209 struct ass_renderer {
 210     ASS_Library *library;
 211     FT_Library ftlibrary;
 212     FCInstance *fontconfig_priv;
 213     ASS_Settings settings;
 214     int render_id;
 215     ASS_SynthPriv *synth_priv;
 216
 217     ASS_Image *images_root;     // rendering result is stored here
 218     ASS_Image *prev_images_root;
 219
 220     EventImages *eimg;          // temporary buffer for sorting rendered events
 221     int eimg_size;              // allocated buffer size
 222
 223     // frame-global data
 224     int width, height;          // screen dimensions
 225     int orig_height;            // frame height ( = screen height - margins )
 226     int orig_width;             // frame width ( = screen width - margins )
 227     int orig_height_nocrop;     // frame height ( = screen height - margins + cropheight)
 228     int orig_width_nocrop;      // frame width ( = screen width - margins + cropwidth)
 229     ASS_Track *track;
 230     long long time;             // frame's timestamp, ms
 231     double font_scale;
 232     double font_scale_x;        // x scale applied to all glyphs to preserve text aspect ratio
 233     double border_scale;
 234
 235     RenderContext state;
 236     TextInfo text_info;
 237     CacheStore cache;
 238
 239     FreeList *free_head;
 240     FreeList *free_tail;
 241 };
 242
 243 typedef struct render_priv {
 244     int top, height, left, width;
 245     int render_id;
 246 } RenderPriv;
 247
 248 typedef struct {
 249     int x0;
 250     int y0;
 251     int x1;
 252     int y1;
 253 } Rect;
 254
 255 typedef struct {
 256     int a, b;                   // top and height
 257     int ha, hb;                 // left and width
 258 } Segment;
 259
 260 void reset_render_context(ASS_Renderer *render_priv);
 261
 262 #endif /* LIBASS_RENDER_H */