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  * Permission to use, copy, modify, and distribute this software for any
   8  * purpose with or without fee is hereby granted, provided that the above
   9  * copyright notice and this permission notice appear in all copies.
  10  *
  11  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
  12  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  13  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  14  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  15  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  16  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  17  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  18  */
  19
  20 #ifndef LIBASS_RENDER_H
  21 #define LIBASS_RENDER_H
  22
  23 #include <inttypes.h>
  24 #include <ft2build.h>
  25 #include FT_FREETYPE_H
  26 #include FT_STROKER_H
  27 #include FT_GLYPH_H
  28 #include FT_SYNTHESIS_H
  29
  30 #include "ass.h"
  31 #include "ass_font.h"
  32 #include "ass_bitmap.h"
  33 #include "ass_cache.h"
  34 #include "ass_utils.h"
  35 #include "ass_fontconfig.h"
  36 #include "ass_library.h"
  37 #include "ass_drawing.h"
  38
  39 #define GLYPH_CACHE_MAX 1000
  40 #define BITMAP_CACHE_MAX_SIZE 30 * 1048576
  41
  42 typedef struct {
  43     double xMin;
  44     double xMax;
  45     double yMin;
  46     double yMax;
  47 } DBBox;
  48
  49 typedef struct {
  50     double x;
  51     double y;
  52 } DVector;
  53
  54 typedef struct free_list {
  55     void *object;
  56     struct free_list *next;
  57 } FreeList;
  58
  59 typedef struct {
  60     int frame_width;
  61     int frame_height;
  62     double font_size_coeff;     // font size multiplier
  63     double line_spacing;        // additional line spacing (in frame pixels)
  64     int top_margin;             // height of top margin. Everything except toptitles is shifted down by top_margin.
  65     int bottom_margin;          // height of bottom margin. (frame_height - top_margin - bottom_margin) is original video height.
  66     int left_margin;
  67     int right_margin;
  68     int use_margins;            // 0 - place all subtitles inside original frame
  69     // 1 - use margins for placing toptitles and subtitles
  70     double aspect;              // frame aspect ratio, d_width / d_height.
  71     double storage_aspect;      // pixel ratio of the source image
  72     ASS_Hinting hinting;
  73
  74     char *default_font;
  75     char *default_family;
  76 } ASS_Settings;
  77
  78 // a rendered event
  79 typedef struct {
  80     ASS_Image *imgs;
  81     int top, height, left, width;
  82     int detect_collisions;
  83     int shift_direction;
  84     ASS_Event *event;
  85 } EventImages;
  86
  87 typedef enum {
  88     EF_NONE = 0,
  89     EF_KARAOKE,
  90     EF_KARAOKE_KF,
  91     EF_KARAOKE_KO
  92 } Effect;
  93
  94 // describes a glyph
  95 // GlyphInfo and TextInfo are used for text centering and word-wrapping operations
  96 typedef struct {
  97     unsigned symbol;
  98     unsigned skip;              // skip glyph when layouting text
  99     FT_Glyph glyph;
 100     FT_Glyph outline_glyph;
 101     Bitmap *bm;                 // glyph bitmap
 102     Bitmap *bm_o;               // outline bitmap
 103     Bitmap *bm_s;               // shadow bitmap
 104     FT_BBox bbox;
 105     FT_Vector pos;
 106     char linebreak;             // the first (leading) glyph of some line ?
 107     uint32_t c[4];              // colors
 108     FT_Vector advance;          // 26.6
 109     Effect effect_type;
 110     int effect_timing;          // time duration of current karaoke word
 111     // after process_karaoke_effects: distance in pixels from the glyph origin.
 112     // part of the glyph to the left of it is displayed in a different color.
 113     int effect_skip_timing;     // delay after the end of last karaoke word
 114     int asc, desc;              // font max ascender and descender
 115     int be;                     // blur edges
 116     double blur;                // gaussian blur
 117     double shadow_x;
 118     double shadow_y;
 119     double frx, fry, frz;       // rotation
 120     double fax, fay;            // text shearing
 121
 122     BitmapHashKey hash_key;
 123 } GlyphInfo;
 124
 125 typedef struct {
 126     double asc, desc;
 127 } LineInfo;
 128
 129 typedef struct {
 130     GlyphInfo *glyphs;
 131     int length;
 132     LineInfo *lines;
 133     int n_lines;
 134     double height;
 135     int max_glyphs;
 136     int max_lines;
 137 } TextInfo;
 138
 139 // Renderer state.
 140 // Values like current font face, color, screen position, clipping and so on are stored here.
 141 typedef struct {
 142     ASS_Event *event;
 143     ASS_Style *style;
 144
 145     ASS_Font *font;
 146     char *font_path;
 147     double font_size;
 148     int flags;                  // decoration flags (underline/strike-through)
 149
 150     FT_Stroker stroker;
 151     int alignment;              // alignment overrides go here; if zero, style value will be used
 152     double frx, fry, frz;
 153     double fax, fay;            // text shearing
 154     enum {
 155         EVENT_NORMAL,           // "normal" top-, sub- or mid- title
 156         EVENT_POSITIONED,       // happens after pos(,), margins are ignored
 157         EVENT_HSCROLL,          // "Banner" transition effect, text_width is unlimited
 158         EVENT_VSCROLL           // "Scroll up", "Scroll down" transition effects
 159     } evt_type;
 160     double pos_x, pos_y;        // position
 161     double org_x, org_y;        // origin
 162     char have_origin;           // origin is explicitly defined; if 0, get_base_point() is used
 163     double scale_x, scale_y;
 164     double hspacing;            // distance between letters, in pixels
 165     double border_x;            // outline width
 166     double border_y;
 167     uint32_t c[4];              // colors(Primary, Secondary, so on) in RGBA
 168     int clip_x0, clip_y0, clip_x1, clip_y1;
 169     char clip_mode;             // 1 = iclip
 170     char detect_collisions;
 171     uint32_t fade;              // alpha from \fad
 172     char be;                    // blur edges
 173     double blur;                // gaussian blur
 174     double shadow_x;
 175     double shadow_y;
 176     int drawing_mode;           // not implemented; when != 0 text is discarded, except for style override tags
 177     ASS_Drawing *drawing;       // current drawing
 178     ASS_Drawing *clip_drawing;  // clip vector
 179     int clip_drawing_mode;      // 0 = regular clip, 1 = inverse clip
 180
 181     Effect effect_type;
 182     int effect_timing;
 183     int effect_skip_timing;
 184
 185     enum {
 186         SCROLL_LR,              // left-to-right
 187         SCROLL_RL,
 188         SCROLL_TB,              // top-to-bottom
 189         SCROLL_BT
 190     } scroll_direction;         // for EVENT_HSCROLL, EVENT_VSCROLL
 191     int scroll_shift;
 192
 193     // face properties
 194     char *family;
 195     unsigned bold;
 196     unsigned italic;
 197     int treat_family_as_pattern;
 198     int wrap_style;
 199 } RenderContext;
 200
 201 typedef struct {
 202     Hashmap *font_cache;
 203     Hashmap *glyph_cache;
 204     Hashmap *bitmap_cache;
 205     Hashmap *composite_cache;
 206     size_t glyph_max;
 207     size_t bitmap_max_size;
 208 } CacheStore;
 209
 210 struct ass_renderer {
 211     ASS_Library *library;
 212     FT_Library ftlibrary;
 213     FCInstance *fontconfig_priv;
 214     ASS_Settings settings;
 215     int render_id;
 216     ASS_SynthPriv *synth_priv;
 217
 218     ASS_Image *images_root;     // rendering result is stored here
 219     ASS_Image *prev_images_root;
 220
 221     EventImages *eimg;          // temporary buffer for sorting rendered events
 222     int eimg_size;              // allocated buffer size
 223
 224     // frame-global data
 225     int width, height;          // screen dimensions
 226     int orig_height;            // frame height ( = screen height - margins )
 227     int orig_width;             // frame width ( = screen width - margins )
 228     int orig_height_nocrop;     // frame height ( = screen height - margins + cropheight)
 229     int orig_width_nocrop;      // frame width ( = screen width - margins + cropwidth)
 230     ASS_Track *track;
 231     long long time;             // frame's timestamp, ms
 232     double font_scale;
 233     double font_scale_x;        // x scale applied to all glyphs to preserve text aspect ratio
 234     double border_scale;
 235
 236     RenderContext state;
 237     TextInfo text_info;
 238     CacheStore cache;
 239
 240     FreeList *free_head;
 241     FreeList *free_tail;
 242 };
 243
 244 typedef struct render_priv {
 245     int top, height, left, width;
 246     int render_id;
 247 } RenderPriv;
 248
 249 typedef struct {
 250     int x0;
 251     int y0;
 252     int x1;
 253     int y1;
 254 } Rect;
 255
 256 typedef struct {
 257     int a, b;                   // top and height
 258     int ha, hb;                 // left and width
 259 } Segment;
 260
 261 void reset_render_context(ASS_Renderer *render_priv);
 262 void ass_free_images(ASS_Image *img);
 263
 264 #endif /* LIBASS_RENDER_H */