Provisional bidi and shaping support

Adds fully working bidirectional text and simple shaping support.
The following works:
- bidirectional text according to the Unicode Bidirectional Algorithm
- simple shaper for mirrored forms (brackets, etc.) according to
  rule L4 of the Unicode Bidirectional Algorithm
- reordering into visual order with correct line wrapping

However, the implementation certainly needs efficiency improvements
(caching, less malloc'ing), a proper shaper (HarfBuzz) needs to be
hooked up and various bugs with karaoke and positioning need to be
fixed.

1 files changed, 28 insertions, 0 deletions

diff --git a/libass/ass_shaper.h b/libass/ass_shaper.h
new file mode 100644
index 0000000..7dc2f27
--- /dev/null
+++ b/libass/ass_shaper.h
@@ -0,0 +1,28 @@
+/*
+ * Copyright (C) 2011 Grigori Goronzy <greg@chown.ath.cx>
+ *
+ * This file is part of libass.
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#ifndef ASS_SHAPER_H
+#define ASS_SHAPER_H
+
+#include <fribidi/fribidi.h>
+
+void ass_shaper_shape(TextInfo *text_info, FriBidiCharType *ctypes,
+                      FriBidiLevel *emblevels);
+void ass_shaper_reorder(TextInfo *text_info, FriBidiCharType *ctypes,
+                        FriBidiLevel *emblevels, FriBidiStrIndex *cmap);
+#endif