/* The glyph cache lock is always held when this function is called. */
static void
do_purge(fz_context *ctx)
{
fz_glyph_cache *cache = ctx->glyph_cache;
int i;
for (i = 0; i < GLYPH_HASH_LEN; i++)
{
while (cache->entry[i])
drop_glyph_cache_entry(ctx, cache->entry[i]);
}
cache->total = 0;
}
fz_glyph *
fz_render_glyph(fz_context *ctx, fz_font *font, int gid, fz_matrix *ctm, fz_colorspace *model, const fz_irect *scissor, int alpha)
{
fz_glyph_cache *cache;
fz_glyph_key key;
fz_matrix subpix_ctm;
fz_irect subpix_scissor;
float size;
fz_glyph *val;
int do_cache, locked, caching;
fz_glyph_cache_entry *entry;
unsigned hash;
fz_var(locked);
fz_var(caching);
fz_var(val);
memset(&key, 0, sizeof key);
size = fz_subpixel_adjust(ctx, ctm, &subpix_ctm, &key.e, &key.f);
if (size <= MAX_GLYPH_SIZE)
{
scissor = &fz_infinite_irect;
do_cache = 1;
}
else
{
if (font->ft_face)
return NULL;
subpix_scissor.x0 = scissor->x0 - floorf(ctm->e);
subpix_scissor.y0 = scissor->y0 - floorf(ctm->f);
subpix_scissor.x1 = scissor->x1 - floorf(ctm->e);
subpix_scissor.y1 = scissor->y1 - floorf(ctm->f);
scissor = &subpix_scissor;
do_cache = 0;
}
cache = ctx->glyph_cache;
key.font = font;
key.gid = gid;
key.a = subpix_ctm.a * 65536;
key.b = subpix_ctm.b * 65536;
key.c = subpix_ctm.c * 65536;
key.d = subpix_ctm.d * 65536;
key.aa = fz_text_aa_level(ctx);
hash = do_hash((unsigned char *)&key, sizeof(key)) % GLYPH_HASH_LEN;
fz_lock(ctx, FZ_LOCK_GLYPHCACHE);
entry = cache->entry[hash];
while (entry)
{
if (memcmp(&entry->key, &key, sizeof(key)) == 0)
{
move_to_front(cache, entry);
val = fz_keep_glyph(ctx, entry->val);
fz_unlock(ctx, FZ_LOCK_GLYPHCACHE);
return val;
}
entry = entry->bucket_next;
}
locked = 1;
caching = 0;
val = NULL;
fz_try(ctx)
{
if (font->ft_face)
{
val = fz_render_ft_glyph(ctx, font, gid, &subpix_ctm, key.aa);
}
else if (font->t3procs)
{
/* We drop the glyphcache here, and execute the t3
* glyph code. The danger here is that some other
* thread will come along, and want the same glyph
* too. If it does, we may both end up rendering
* pixmaps. We cope with this later on, by ensuring
* that only one gets inserted into the cache. If
* we insert ours to find one already there, we
* abandon ours, and use the one there already.
*/
fz_unlock(ctx, FZ_LOCK_GLYPHCACHE);
locked = 0;
val = fz_render_t3_glyph(ctx, font, gid, &subpix_ctm, model, scissor);
fz_lock(ctx, FZ_LOCK_GLYPHCACHE);
locked = 1;
}
else
{
fz_warn(ctx, "assert: uninitialized font structure");
}
if (val && do_cache)
{
if (val->w < MAX_GLYPH_SIZE && val->h < MAX_GLYPH_SIZE)
{
/* If we throw an exception whilst caching,
* just ignore the exception and carry on. */
caching = 1;
if (!font->ft_face)
{
/* We had to unlock. Someone else might
* have rendered in the meantime */
entry = cache->entry[hash];
while (entry)
{
if (memcmp(&entry->key, &key, sizeof(key)) == 0)
{
fz_drop_glyph(ctx, val);
move_to_front(cache, entry);
val = fz_keep_glyph(ctx, entry->val);
goto unlock_and_return_val;
}
entry = entry->bucket_next;
}
}
entry = fz_malloc_struct(ctx, fz_glyph_cache_entry);
entry->key = key;
entry->hash = hash;
entry->bucket_next = cache->entry[hash];
if (entry->bucket_next)
entry->bucket_next->bucket_prev = entry;
cache->entry[hash] = entry;
entry->val = fz_keep_glyph(ctx, val);
fz_keep_font(ctx, key.font);
entry->lru_next = cache->lru_head;
if (entry->lru_next)
entry->lru_next->lru_prev = entry;
else
cache->lru_tail = entry;
cache->lru_head = entry;
cache->total += fz_glyph_size(ctx, val);
while (cache->total > MAX_CACHE_SIZE)
{
#ifndef NDEBUG
cache->num_evictions++;
cache->evicted += fz_glyph_size(ctx, cache->lru_tail->val);
#endif
drop_glyph_cache_entry(ctx, cache->lru_tail);
}
}
}
unlock_and_return_val:
{
}
}
fz_always(ctx)
{
if (locked)
fz_unlock(ctx, FZ_LOCK_GLYPHCACHE);
}
fz_catch(ctx)
{
if (caching)
fz_warn(ctx, "cannot encache glyph; continuing");
else
fz_rethrow(ctx);
}
return val;
}
/*
Render a glyph and return a bitmap.
If the glyph is too large to fit the cache we have two choices:
1) Return NULL so the caller can draw the glyph using an outline.
Only supported for freetype fonts.
2) Render a clipped glyph by using the scissor rectangle.
Only supported for type 3 fonts.
This must not be inserted into the cache.
*/
fz_pixmap *
fz_render_glyph(fz_context *ctx, fz_font *font, int gid, const fz_matrix *ctm, fz_colorspace *model, fz_irect scissor)
{
fz_glyph_cache *cache;
fz_glyph_key key;
fz_pixmap *val;
float size = fz_matrix_expansion(ctm);
int do_cache, locked, caching;
fz_matrix local_ctm = *ctm;
fz_glyph_cache_entry *entry;
unsigned hash;
fz_var(locked);
fz_var(caching);
if (size <= MAX_GLYPH_SIZE)
{
scissor = fz_infinite_irect;
do_cache = 1;
}
else
{
/* SumatraPDF: don't break clipping by larger glyphs */
if (font->ft_face && size > 3000)
return NULL;
do_cache = 0;
}
cache = ctx->glyph_cache;
memset(&key, 0, sizeof key);
key.font = font;
key.gid = gid;
key.a = local_ctm.a * 65536;
key.b = local_ctm.b * 65536;
key.c = local_ctm.c * 65536;
key.d = local_ctm.d * 65536;
key.e = (local_ctm.e - floorf(local_ctm.e)) * 256;
key.f = (local_ctm.f - floorf(local_ctm.f)) * 256;
key.aa = fz_aa_level(ctx);
local_ctm.e = floorf(local_ctm.e) + key.e / 256.0f;
local_ctm.f = floorf(local_ctm.f) + key.f / 256.0f;
fz_lock(ctx, FZ_LOCK_GLYPHCACHE);
hash = do_hash((unsigned char *)&key, sizeof(key)) % GLYPH_HASH_LEN;
entry = cache->entry[hash];
while (entry)
{
if (memcmp(&entry->key, &key, sizeof(key)) == 0)
{
move_to_front(cache, entry);
val = fz_keep_pixmap(ctx, entry->val);
fz_unlock(ctx, FZ_LOCK_GLYPHCACHE);
return val;
}
entry = entry->bucket_next;
}
locked = 1;
caching = 0;
fz_try(ctx)
{
if (font->ft_face)
{
val = fz_render_ft_glyph(ctx, font, gid, &local_ctm, key.aa);
}
else if (font->t3procs)
{
/* We drop the glyphcache here, and execute the t3
* glyph code. The danger here is that some other
* thread will come along, and want the same glyph
* too. If it does, we may both end up rendering
* pixmaps. We cope with this later on, by ensuring
* that only one gets inserted into the cache. If
* we insert ours to find one already there, we
* abandon ours, and use the one there already.
*/
fz_unlock(ctx, FZ_LOCK_GLYPHCACHE);
locked = 0;
val = fz_render_t3_glyph(ctx, font, gid, &local_ctm, model, scissor);
fz_lock(ctx, FZ_LOCK_GLYPHCACHE);
locked = 1;
}
else
{
fz_warn(ctx, "assert: uninitialized font structure");
val = NULL;
}
if (val && do_cache)
{
if (val->w < MAX_GLYPH_SIZE && val->h < MAX_GLYPH_SIZE)
{
/* If we throw an exception whilst caching,
* just ignore the exception and carry on. */
caching = 1;
if (!font->ft_face)
{
/* We had to unlock. Someone else might
* have rendered in the meantime */
entry = cache->entry[hash];
while (entry)
{
if (memcmp(&entry->key, &key, sizeof(key)) == 0)
{
fz_drop_pixmap(ctx, val);
move_to_front(cache, entry);
val = fz_keep_pixmap(ctx, entry->val);
fz_unlock(ctx, FZ_LOCK_GLYPHCACHE);
return val;
}
entry = entry->bucket_next;
}
}
entry = fz_malloc_struct(ctx, fz_glyph_cache_entry);
entry->key = key;
entry->hash = hash;
entry->bucket_next = cache->entry[hash];
if (entry->bucket_next)
entry->bucket_next->bucket_prev = entry;
cache->entry[hash] = entry;
entry->val = fz_keep_pixmap(ctx, val);
fz_keep_font(ctx, key.font);
entry->lru_next = cache->lru_head;
if (entry->lru_next)
entry->lru_next->lru_prev = entry;
else
cache->lru_tail = entry;
cache->lru_head = entry;
cache->total += val->w * val->h;
while (cache->total > MAX_CACHE_SIZE)
{
drop_glyph_cache_entry(ctx, cache->lru_tail);
}
}
}
}
fz_always(ctx)
{
if (locked)
fz_unlock(ctx, FZ_LOCK_GLYPHCACHE);
}
fz_catch(ctx)
{
if (caching)
fz_warn(ctx, "cannot encache glyph; continuing");
else
fz_rethrow(ctx);
}
return val;
}
