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 #define GLYPH_CACHE_MAX 1000
  42 #define BITMAP_CACHE_MAX_SIZE 30 * 1048576
  43
  44 typedef struct {
  45     double xMin;
  46     double xMax;
  47     double yMin;
  48     double yMax;
  49 } DBBox;
  50
  51 typedef struct {
  52     double x;
  53     double y;
  54 } DVector;
  55
  56 typedef struct free_list {
  57     void *object;
  58     struct free_list *next;
  59 } FreeList;
  60
  61 typedef struct {
  62     int frame_width;
  63     int frame_height;
  64     double font_size_coeff;     // font size multiplier
  65     double line_spacing;        // additional line spacing (in frame pixels)
  66     int top_margin;             // height of top margin. Everything except toptitles is shifted down by top_margin.
  67     int bottom_margin;          // height of bottom margin. (frame_height - top_margin - bottom_margin) is original video height.
  68     int left_margin;
  69     int right_margin;
  70     int use_margins;            // 0 - place all subtitles inside original frame
  71     // 1 - use margins for placing toptitles and subtitles
  72     double aspect;              // frame aspect ratio, d_width / d_height.
  73     double storage_aspect;      // pixel ratio of the source image
  74     ASS_Hinting hinting;
  75
  76     char *default_font;
  77     char *default_family;
  78 } ASS_Settings;
  79
  80 // a rendered event
  81 typedef struct {
  82     ASS_Image *imgs;
  83     int top, height, left, width;
  84     int detect_collisions;
  85     int shift_direction;
  86     ASS_Event *event;
  87 } EventImages;
  88
  89 typedef enum {
  90     EF_NONE = 0,
  91     EF_KARAOKE,
  92     EF_KARAOKE_KF,
  93     EF_KARAOKE_KO
  94 } Effect;
  95
  96 // describes a glyph
  97 // GlyphInfo and TextInfo are used for text centering and word-wrapping operations
  98 typedef struct {
  99     unsigned symbol;
 100     unsigned skip;              // skip glyph when layouting text
 101     FT_Glyph glyph;
 102     FT_Glyph outline_glyph;
 103     Bitmap *bm;                 // glyph bitmap
 104     Bitmap *bm_o;               // outline bitmap
 105     Bitmap *bm_s;               // shadow bitmap
 106     FT_BBox bbox;
 107     FT_Vector pos;
 108     char linebreak;             // the first (leading) glyph of some line ?
 109     uint32_t c[4];              // colors
 110     FT_Vector advance;          // 26.6
 111     Effect effect_type;
 112     int effect_timing;          // time duration of current karaoke word
 113     // after process_karaoke_effects: distance in pixels from the glyph origin.
 114     // part of the glyph to the left of it is displayed in a different color.
 115     int effect_skip_timing;     // delay after the end of last karaoke word
 116     int asc, desc;              // font max ascender and descender
 117     int be;                     // blur edges
 118     double blur;                // gaussian blur
 119     double shadow_x;
 120     double shadow_y;
 121     double frx, fry, frz;       // rotation
 122     double fax, fay;            // text shearing
 123
 124     BitmapHashKey hash_key;
 125 } GlyphInfo;
 126
 127 typedef struct {
 128     double asc, desc;
 129 } LineInfo;
 130
 131 typedef struct {
 132     GlyphInfo *glyphs;
 133     int length;
 134     LineInfo *lines;
 135     int n_lines;
 136     double height;
 137     int max_glyphs;
 138     int max_lines;
 139 } TextInfo;
 140
 141 // Renderer state.
 142 // Values like current font face, color, screen position, clipping and so on are stored here.
 143 typedef struct {
 144     ASS_Event *event;
 145     ASS_Style *style;
 146
 147     ASS_Font *font;
 148     char *font_path;
 149     double font_size;
 150     int flags;                  // decoration flags (underline/strike-through)
 151
 152     FT_Stroker stroker;
 153     int alignment;              // alignment overrides go here; if zero, style value will be used
 154     double frx, fry, frz;
 155     double fax, fay;            // text shearing
 156     enum {
 157         EVENT_NORMAL,           // "normal" top-, sub- or mid- title
 158         EVENT_POSITIONED,       // happens after pos(,), margins are ignored
 159         EVENT_HSCROLL,          // "Banner" transition effect, text_width is unlimited
 160         EVENT_VSCROLL           // "Scroll up", "Scroll down" transition effects
 161     } evt_type;
 162     double pos_x, pos_y;        // position
 163     double org_x, org_y;        // origin
 164     char have_origin;           // origin is explicitly defined; if 0, get_base_point() is used
 165     double scale_x, scale_y;
 166     double hspacing;            // distance between letters, in pixels
 167     double border_x;            // outline width
 168     double border_y;
 169     uint32_t c[4];              // colors(Primary, Secondary, so on) in RGBA
 170     int clip_x0, clip_y0, clip_x1, clip_y1;
 171     char clip_mode;             // 1 = iclip
 172     char detect_collisions;
 173     uint32_t fade;              // alpha from \fad
 174     char be;                    // blur edges
 175     double blur;                // gaussian blur
 176     double shadow_x;
 177     double shadow_y;
 178     int drawing_mode;           // not implemented; when != 0 text is discarded, except for style override tags
 179     ASS_Drawing *drawing;       // current drawing
 180     ASS_Drawing *clip_drawing;  // clip vector
 181     int clip_drawing_mode;      // 0 = regular clip, 1 = inverse clip
 182
 183     Effect effect_type;
 184     int effect_timing;
 185     int effect_skip_timing;
 186
 187     enum {
 188         SCROLL_LR,              // left-to-right
 189         SCROLL_RL,
 190         SCROLL_TB,              // top-to-bottom
 191         SCROLL_BT
 192     } scroll_direction;         // for EVENT_HSCROLL, EVENT_VSCROLL
 193     int scroll_shift;
 194
 195     // face properties
 196     char *family;
 197     unsigned bold;
 198     unsigned italic;
 199     int treat_family_as_pattern;
 200     int wrap_style;
 201 } RenderContext;
 202
 203 typedef struct {
 204     Hashmap *font_cache;
 205     Hashmap *glyph_cache;
 206     Hashmap *bitmap_cache;
 207     Hashmap *composite_cache;
 208     size_t glyph_max;
 209     size_t bitmap_max_size;
 210 } CacheStore;
 211
 212 struct ass_renderer {
 213     ASS_Library *library;
 214     FT_Library ftlibrary;
 215     FCInstance *fontconfig_priv;
 216     ASS_Settings settings;
 217     int render_id;
 218     ASS_SynthPriv *synth_priv;
 219
 220     ASS_Image *images_root;     // rendering result is stored here
 221     ASS_Image *prev_images_root;
 222
 223     EventImages *eimg;          // temporary buffer for sorting rendered events
 224     int eimg_size;              // allocated buffer size
 225
 226     // frame-global data
 227     int width, height;          // screen dimensions
 228     int orig_height;            // frame height ( = screen height - margins )
 229     int orig_width;             // frame width ( = screen width - margins )
 230     int orig_height_nocrop;     // frame height ( = screen height - margins + cropheight)
 231     int orig_width_nocrop;      // frame width ( = screen width - margins + cropwidth)
 232     ASS_Track *track;
 233     long long time;             // frame's timestamp, ms
 234     double font_scale;
 235     double font_scale_x;        // x scale applied to all glyphs to preserve text aspect ratio
 236     double border_scale;
 237
 238     RenderContext state;
 239     TextInfo text_info;
 240     CacheStore cache;
 241
 242     FreeList *free_head;
 243     FreeList *free_tail;
 244 };
 245
 246 typedef struct render_priv {
 247     int top, height, left, width;
 248     int render_id;
 249 } RenderPriv;
 250
 251 typedef struct {
 252     int x0;
 253     int y0;
 254     int x1;
 255     int y1;
 256 } Rect;
 257
 258 typedef struct {
 259     int a, b;                   // top and height
 260     int ha, hb;                 // left and width
 261 } Segment;
 262
 263 void reset_render_context(ASS_Renderer *render_priv);
 264 void ass_free_images(ASS_Image *img);
 265
 266 #endif /* LIBASS_RENDER_H */