Clean up bitmap combining

Now pre- and post-combining operations are clearly separated,
many parameters in cache keys are no longer necessary due to that.
Also an ambiguous (in case of multiple fonts) text string is replaced
with a list of direct bitmap references in composite cache key.

Fixes #153.
Fixes #82.

1 files changed, 18 insertions, 2 deletions

diff --git a/libass/ass_cache.h b/libass/ass_cache.h
index 0600142..af814ac 100644
--- a/libass/ass_cache.h
+++ b/libass/ass_cache.h
@@ -31,14 +31,12 @@ typedef struct cache Cache;
 typedef struct {
     Bitmap *bm;               // the actual bitmaps
     Bitmap *bm_o;
-    Bitmap *bm_s;
 } BitmapHashValue;
 
 typedef struct {
     Bitmap *bm;
     Bitmap *bm_o;
     Bitmap *bm_s;
-    FT_Vector pos;
 } CompositeHashValue;
 
 typedef struct {
@@ -87,6 +85,24 @@ typedef struct bitmap_hash_key {
     } u;
 } BitmapHashKey;
 
+typedef struct {
+    BitmapHashValue *image;
+    int x, y;
+} BitmapRef;
+
+enum {
+    FILTER_BORDER_STYLE_3 = 1,
+    FILTER_NONZERO_BORDER = 2,
+    FILTER_NONZERO_SHADOW = 4,
+    FILTER_DRAW_SHADOW    = 8,  // VSFilter compatibility
+};
+
+typedef struct {
+    FilterDesc filter;
+    size_t bitmap_count;
+    BitmapRef *bitmaps;
+} CompositeHashKey;
+
 Cache *ass_cache_create(HashFunction hash_func, HashCompare compare_func,
                         CacheItemDestructor destruct_func, ItemSize size_func,
                         size_t key_size, size_t value_size);