diff options
| -rw-r--r-- | ChangeLog | 18 | ||||
| -rw-r--r-- | pango/pangocairo-fcfont.c | 111 |
2 files changed, 129 insertions, 0 deletions
@@ -1,3 +1,21 @@ +2005-11-04 Federico Mena Quintero <federico@ximian.com> + + Fixes #320665: + + * pango/pangocairo-fcfont.c: Use a simple, fixed-size cache to map + gunichars to glyph indices within the font. The cache is + described in detail here: + http://primates.ximian.com/~federico/news-2005-10.html#gtkfilechooser-profile-5 + (GlyphCacheEntry): new structure to hold a gunichar and a PangoGlyph. + (struct _PangoCairoFcFont): Add a char_to_glyph_cache field. + (pango_cairo_fc_font_get_glyph): Allocate the char_to_glyph_cache + if needed. We do it on demand because while many fonts will be + alive at any one time (in order to cover the whole Unicode space), + only very few of them will be actually accessed for glyph lookups. + (pango_cairo_fc_font_get_glyph): Look up the gunichar in the + cache, and replace the cache entry if necessary. + (pango_cairo_fc_font_finalize): Free the char_to_glyph_cache. + 2005-11-04 Behdad Esfahbod <behdad@gnome.org> * pango/pangocairo-fontmap.c: Use quarks for GObject data to improve diff --git a/pango/pangocairo-fcfont.c b/pango/pangocairo-fcfont.c index eb6825ef..156ff988 100644 --- a/pango/pangocairo-fcfont.c +++ b/pango/pangocairo-fcfont.c @@ -44,6 +44,32 @@ typedef struct _PangoCairoFcFont PangoCairoFcFont; typedef struct _PangoCairoFcFontClass PangoCairoFcFontClass; typedef struct _PangoCairoFcGlyphInfo PangoCairoFcGlyphInfo; +#undef PROFILE_GLYPH_CACHE +#ifdef PROFILE_GLYPH_CACHE +static long num_cairo_fc_fonts; +static long max_cairo_fc_fonts; +static long num_glyph_caches; +static long max_glyph_caches; +static long num_glyph_cache_hits; +static long num_glyph_cache_misses; +#endif + +#define GLYPH_CACHE_NUM_ENTRIES 256 +#define GLYPH_CACHE_MASK 0x000000ff + +/* An entry in the fixed-size cache for the gunichar -> glyph mapping. The + * cache is indexed by the lower N bits of the gunichar (see + * GLYPH_CACHE_NUM_ENTRIES and GLYPH_CACHE_MASK above). For scripts with few + * code points, this should provide pretty much instant lookups. + * + * The "ch" field is zero if that cache entry is invalid. + */ +typedef struct +{ + gunichar ch; + PangoGlyph glyph; +} GlyphCacheEntry; + struct _PangoCairoFcFont { PangoFcFont font; @@ -55,6 +81,8 @@ struct _PangoCairoFcFont cairo_font_options_t *options; GHashTable *glyph_info; + + GlyphCacheEntry *char_to_glyph_cache; }; struct _PangoCairoFcFontClass @@ -161,7 +189,21 @@ pango_cairo_fc_font_finalize (GObject *object) g_hash_table_destroy (cffont->glyph_info); + if (cffont->char_to_glyph_cache) + { + g_free (cffont->char_to_glyph_cache); +#ifdef PROFILE_GLYPH_CACHE + num_glyph_caches--; + g_assert (num_glyph_caches >= 0); +#endif + } + G_OBJECT_CLASS (pango_cairo_fc_font_parent_class)->finalize (object); + +#ifdef PROFILE_GLYPH_CACHE + num_cairo_fc_fonts--; + g_assert (num_cairo_fc_fonts >= 0); +#endif } static void @@ -313,6 +355,52 @@ pango_cairo_fc_font_unlock_face (PangoFcFont *font) } static PangoGlyph +pango_cairo_fc_font_get_glyph (PangoFcFont *font, + gunichar wc) +{ + PangoCairoFcFont *cffont = (PangoCairoFcFont *)font; + guint idx; + GlyphCacheEntry *entry; + + /* We create the cache dynamically because although we'll have a lot of + * PangoCairoFcFont structures (one per font in the fontset, as many as needed + * to cover the whole Unicode space), we'll only end up using a few of them + * for the user's actual text. + */ + if (cffont->char_to_glyph_cache == NULL) + { + cffont->char_to_glyph_cache = g_new0 (GlyphCacheEntry, GLYPH_CACHE_NUM_ENTRIES); +#ifdef PROFILE_GLYPH_CACHE + num_glyph_caches++; + if (num_glyph_caches > max_glyph_caches) + max_glyph_caches = num_glyph_caches; +#endif + } + + idx = wc & GLYPH_CACHE_MASK; + entry = cffont->char_to_glyph_cache + idx; + + if (entry->ch != wc || wc == 0) + { +#ifdef PROFILE_GLYPH_CACHE + num_glyph_cache_misses++; +/* printf ("cache MISS: cffont %p, gunichar %x = '%c'\n", cffont, wc, (wc < 128) ? wc : 0); */ +#endif + entry->ch = wc; + entry->glyph = ((PangoFcFontClass *) pango_cairo_fc_font_parent_class)->get_glyph (font, wc); + } + else + { +#ifdef PROFILE_GLYPH_CACHE + num_glyph_cache_hits++; +/* printf ("cache HIT: cffont %p, gunichar %x = '%c'\n", cffont, wc, (wc < 128) ? wc : 0); */ +#endif + } + + return entry->glyph; +} + +static PangoGlyph pango_cairo_fc_font_real_get_unknown_glyph (PangoFcFont *font, gunichar wc) { @@ -335,6 +423,18 @@ pango_cairo_fc_font_shutdown (PangoFcFont *fcfont) } } +#ifdef PROFILE_GLYPH_CACHE +static void +profile_glyph_cache_exit_cb (void) +{ + printf ("Maximum number of PangoCairoFcFont objects: %ld\n", max_cairo_fc_fonts); + printf ("Maximum number of glyph caches created: %ld (%ld KB)\n", max_glyph_caches, (max_glyph_caches * sizeof (GlyphCacheEntry) * GLYPH_CACHE_NUM_ENTRIES) / 1024); + printf ("Glyph cache hits: %ld\n", num_glyph_cache_hits); + printf ("Glyph cache misses: %ld\n", num_glyph_cache_misses); + printf ("Glyph cache miss rate: %f%%\n", 100.0 * (double) num_glyph_cache_misses / (num_glyph_cache_misses + num_glyph_cache_hits)); +} +#endif + static void pango_cairo_fc_font_class_init (PangoCairoFcFontClass *class) { @@ -349,8 +449,13 @@ pango_cairo_fc_font_class_init (PangoCairoFcFontClass *class) fc_font_class->lock_face = pango_cairo_fc_font_lock_face; fc_font_class->unlock_face = pango_cairo_fc_font_unlock_face; + fc_font_class->get_glyph = pango_cairo_fc_font_get_glyph; fc_font_class->get_unknown_glyph = pango_cairo_fc_font_real_get_unknown_glyph; fc_font_class->shutdown = pango_cairo_fc_font_shutdown; + +#ifdef PROFILE_GLYPH_CACHE + atexit (profile_glyph_cache_exit_cb); +#endif } static void @@ -360,6 +465,12 @@ pango_cairo_fc_font_init (PangoCairoFcFont *cffont) NULL, NULL, (GDestroyNotify)g_free); + +#ifdef PROFILE_GLYPH_CACHE + num_cairo_fc_fonts++; + if (num_cairo_fc_fonts > max_cairo_fc_fonts) + max_cairo_fc_fonts = num_cairo_fc_fonts; +#endif } /******************** |