Add South-East Asian shaper
Handles Tai Tham, Cham, and New Tai Lue for now.
diff --git a/src/hb-ot-shape-complex-indic.cc b/src/hb-ot-shape-complex-indic.cc
index 9c704fb..fe62783 100644
--- a/src/hb-ot-shape-complex-indic.cc
+++ b/src/hb-ot-shape-complex-indic.cc
@@ -27,6 +27,245 @@
#include "hb-ot-shape-complex-indic-private.hh"
#include "hb-ot-layout-private.hh"
+/* buffer var allocations */
+#define indic_category() complex_var_u8_0() /* indic_category_t */
+#define indic_position() complex_var_u8_1() /* indic_position_t */
+
+
+/*
+ * Indic shaper.
+ */
+
+
+#define IN_HALF_BLOCK(u, Base) (((u) & ~0x7F) == (Base))
+
+#define IS_DEVA(u) (IN_HALF_BLOCK (u, 0x0900))
+#define IS_BENG(u) (IN_HALF_BLOCK (u, 0x0980))
+#define IS_GURU(u) (IN_HALF_BLOCK (u, 0x0A00))
+#define IS_GUJR(u) (IN_HALF_BLOCK (u, 0x0A80))
+#define IS_ORYA(u) (IN_HALF_BLOCK (u, 0x0B00))
+#define IS_TAML(u) (IN_HALF_BLOCK (u, 0x0B80))
+#define IS_TELU(u) (IN_HALF_BLOCK (u, 0x0C00))
+#define IS_KNDA(u) (IN_HALF_BLOCK (u, 0x0C80))
+#define IS_MLYM(u) (IN_HALF_BLOCK (u, 0x0D00))
+#define IS_SINH(u) (IN_HALF_BLOCK (u, 0x0D80))
+#define IS_KHMR(u) (IN_HALF_BLOCK (u, 0x1780))
+
+
+#define MATRA_POS_LEFT(u) POS_PRE_M
+#define MATRA_POS_RIGHT(u) ( \
+ IS_DEVA(u) ? POS_AFTER_SUB : \
+ IS_BENG(u) ? POS_AFTER_POST : \
+ IS_GURU(u) ? POS_AFTER_POST : \
+ IS_GUJR(u) ? POS_AFTER_POST : \
+ IS_ORYA(u) ? POS_AFTER_POST : \
+ IS_TAML(u) ? POS_AFTER_POST : \
+ IS_TELU(u) ? (u <= 0x0C42 ? POS_BEFORE_SUB : POS_AFTER_SUB) : \
+ IS_KNDA(u) ? (u < 0x0CC3 || u > 0xCD6 ? POS_BEFORE_SUB : POS_AFTER_SUB) : \
+ IS_MLYM(u) ? POS_AFTER_POST : \
+ IS_SINH(u) ? POS_AFTER_SUB : \
+ IS_KHMR(u) ? POS_AFTER_POST : \
+ /*default*/ POS_AFTER_SUB \
+ )
+#define MATRA_POS_TOP(u) ( /* BENG and MLYM don't have top matras. */ \
+ IS_DEVA(u) ? POS_AFTER_SUB : \
+ IS_GURU(u) ? POS_AFTER_POST : /* Deviate from spec */ \
+ IS_GUJR(u) ? POS_AFTER_SUB : \
+ IS_ORYA(u) ? POS_AFTER_MAIN : \
+ IS_TAML(u) ? POS_AFTER_SUB : \
+ IS_TELU(u) ? POS_BEFORE_SUB : \
+ IS_KNDA(u) ? POS_BEFORE_SUB : \
+ IS_SINH(u) ? POS_AFTER_SUB : \
+ IS_KHMR(u) ? POS_AFTER_POST : \
+ /*default*/ POS_AFTER_SUB \
+ )
+#define MATRA_POS_BOTTOM(u) ( \
+ IS_DEVA(u) ? POS_AFTER_SUB : \
+ IS_BENG(u) ? POS_AFTER_SUB : \
+ IS_GURU(u) ? POS_AFTER_POST : \
+ IS_GUJR(u) ? POS_AFTER_POST : \
+ IS_ORYA(u) ? POS_AFTER_SUB : \
+ IS_TAML(u) ? POS_AFTER_POST : \
+ IS_TELU(u) ? POS_BEFORE_SUB : \
+ IS_KNDA(u) ? POS_BEFORE_SUB : \
+ IS_MLYM(u) ? POS_AFTER_POST : \
+ IS_SINH(u) ? POS_AFTER_SUB : \
+ IS_KHMR(u) ? POS_AFTER_POST : \
+ /*default*/ POS_AFTER_SUB \
+ )
+
+static inline indic_position_t
+matra_position (hb_codepoint_t u, indic_position_t side)
+{
+ switch ((int) side)
+ {
+ case POS_PRE_C: return MATRA_POS_LEFT (u);
+ case POS_POST_C: return MATRA_POS_RIGHT (u);
+ case POS_ABOVE_C: return MATRA_POS_TOP (u);
+ case POS_BELOW_C: return MATRA_POS_BOTTOM (u);
+ };
+ return side;
+}
+
+/* XXX
+ * This is a hack for now. We should move this data into the main Indic table.
+ * Or completely remove it and just check in the tables.
+ */
+static const hb_codepoint_t ra_chars[] = {
+ 0x0930, /* Devanagari */
+ 0x09B0, /* Bengali */
+ 0x09F0, /* Bengali */
+ 0x0A30, /* Gurmukhi */ /* No Reph */
+ 0x0AB0, /* Gujarati */
+ 0x0B30, /* Oriya */
+ 0x0BB0, /* Tamil */ /* No Reph */
+ 0x0C30, /* Telugu */ /* Reph formed only with ZWJ */
+ 0x0CB0, /* Kannada */
+ 0x0D30, /* Malayalam */ /* No Reph, Logical Repha */
+
+ 0x0DBB, /* Sinhala */ /* Reph formed only with ZWJ */
+
+ 0x179A, /* Khmer */ /* No Reph, Visual Repha */
+};
+
+static inline indic_position_t
+consonant_position (hb_codepoint_t u)
+{
+ if ((u & ~0x007F) == 0x1780)
+ return POS_BELOW_C; /* In Khmer coeng model, post and below forms should not be reordered. */
+ return POS_BASE_C; /* Will recategorize later based on font lookups. */
+}
+
+static inline bool
+is_ra (hb_codepoint_t u)
+{
+ for (unsigned int i = 0; i < ARRAY_LENGTH (ra_chars); i++)
+ if (u == ra_chars[i])
+ return true;
+ return false;
+}
+
+static inline bool
+is_one_of (const hb_glyph_info_t &info, unsigned int flags)
+{
+ /* If it ligated, all bets are off. */
+ if (is_a_ligature (info)) return false;
+ return !!(FLAG (info.indic_category()) & flags);
+}
+
+#define JOINER_FLAGS (FLAG (OT_ZWJ) | FLAG (OT_ZWNJ))
+static inline bool
+is_joiner (const hb_glyph_info_t &info)
+{
+ return is_one_of (info, JOINER_FLAGS);
+}
+
+/* Note:
+ *
+ * We treat Vowels and placeholders as if they were consonants. This is safe because Vowels
+ * cannot happen in a consonant syllable. The plus side however is, we can call the
+ * consonant syllable logic from the vowel syllable function and get it all right! */
+#define CONSONANT_FLAGS (FLAG (OT_C) | FLAG (OT_CM) | FLAG (OT_Ra) | FLAG (OT_V) | FLAG (OT_NBSP) | FLAG (OT_DOTTEDCIRCLE))
+static inline bool
+is_consonant (const hb_glyph_info_t &info)
+{
+ return is_one_of (info, CONSONANT_FLAGS);
+}
+
+#define HALANT_OR_COENG_FLAGS (FLAG (OT_H) | FLAG (OT_Coeng))
+static inline bool
+is_halant_or_coeng (const hb_glyph_info_t &info)
+{
+ return is_one_of (info, HALANT_OR_COENG_FLAGS);
+}
+
+static inline void
+set_indic_properties (hb_glyph_info_t &info)
+{
+ hb_codepoint_t u = info.codepoint;
+ unsigned int type = hb_indic_get_categories (u);
+ indic_category_t cat = (indic_category_t) (type & 0x7F);
+ indic_position_t pos = (indic_position_t) (type >> 8);
+
+
+ /*
+ * Re-assign category
+ */
+
+
+ /* The spec says U+0952 is OT_A. However, testing shows that Uniscribe
+ * treats U+0951..U+0952 all as OT_VD.
+ * TESTS:
+ * U+092E,U+0947,U+0952
+ * U+092E,U+0952,U+0947
+ * U+092E,U+0947,U+0951
+ * U+092E,U+0951,U+0947
+ * */
+ if (unlikely (hb_in_range<hb_codepoint_t> (u, 0x0951, 0x0954)))
+ cat = OT_VD;
+
+ if (unlikely (u == 0x17D1))
+ cat = OT_X;
+ if (cat == OT_X &&
+ unlikely (hb_in_range<hb_codepoint_t> (u, 0x17CB, 0x17D3))) /* Khmer Various signs */
+ {
+ /* These are like Top Matras. */
+ cat = OT_M;
+ pos = POS_ABOVE_C;
+ }
+ if (u == 0x17C6) /* Khmer Bindu doesn't like to be repositioned. */
+ cat = OT_N;
+
+ if (unlikely (u == 0x17D2)) cat = OT_Coeng; /* Khmer coeng */
+ else if (unlikely (u == 0x200C)) cat = OT_ZWNJ;
+ else if (unlikely (u == 0x200D)) cat = OT_ZWJ;
+ else if (unlikely (u == 0x25CC)) cat = OT_DOTTEDCIRCLE;
+ else if (unlikely (u == 0x0A71)) cat = OT_SM; /* GURMUKHI ADDAK. More like consonant medial. like 0A75. */
+
+ if (cat == OT_Repha) {
+ /* There are two kinds of characters marked as Repha:
+ * - The ones that are GenCat=Mn are already positioned visually, ie. after base. (eg. Khmer)
+ * - The ones that are GenCat=Lo is encoded logically, ie. beginning of syllable. (eg. Malayalam)
+ *
+ * We recategorize the first kind to look like a Nukta and attached to the base directly.
+ */
+ if (_hb_glyph_info_get_general_category (&info) == HB_UNICODE_GENERAL_CATEGORY_NON_SPACING_MARK)
+ cat = OT_N;
+ }
+
+
+
+ /*
+ * Re-assign position.
+ */
+
+ if ((FLAG (cat) & CONSONANT_FLAGS))
+ {
+ pos = consonant_position (u);
+ if (is_ra (u))
+ cat = OT_Ra;
+ }
+ else if (cat == OT_M)
+ {
+ pos = matra_position (u, pos);
+ }
+ else if (cat == OT_SM || cat == OT_VD)
+ {
+ pos = POS_SMVD;
+ }
+
+ if (unlikely (u == 0x0B01)) pos = POS_BEFORE_SUB; /* Oriya Bindu is BeforeSub in the spec. */
+
+
+
+ info.indic_category() = cat;
+ info.indic_position() = pos;
+}
+
+/*
+ * Things above this line should ideally be moved to the Indic table itself.
+ */
+
/*
* Global Indic shaper options.
