From 5d34164d98f04816aafaa0abfc44cd899c7d70b3 Mon Sep 17 00:00:00 2001 From: Behdad Esfahbod Date: Wed, 10 Oct 2018 18:14:41 -0400 Subject: [PATCH] [kern/kerx] Fix offset base Disable kern Format2. Fix kerx Format2. Manually tested this with Tamil MN font and it works: $ HB_OPTIONS=aat ./hb-shape Tamil\ MN.ttc -u 0B94,0B95 [tgv_au=0+3435|tgc_ka=1@-75,0+1517] HB_OPTIONS=aat ./hb-shape Tamil\ MN.ttc -u 0B94,0B95 --features=-kern [tgv_au=0+3510|tgc_ka=1+1592] --- src/hb-aat-layout-kerx-table.hh | 73 ++++++++++++++++++++------------- src/hb-ot-kern-table.hh | 7 ++++ 2 files changed, 52 insertions(+), 28 deletions(-) diff --git a/src/hb-aat-layout-kerx-table.hh b/src/hb-aat-layout-kerx-table.hh index f5540b6e9..2214265b5 100644 --- a/src/hb-aat-layout-kerx-table.hh +++ b/src/hb-aat-layout-kerx-table.hh @@ -44,6 +44,22 @@ namespace AAT { using namespace OT; +struct KerxSubTableHeader +{ + inline bool sanitize (hb_sanitize_context_t *c) const + { + TRACE_SANITIZE (this); + return_trace (likely (c->check_struct (this))); + } + + public: + HBUINT32 length; + HBUINT32 coverage; + HBUINT32 tupleCount; + public: + DEFINE_SIZE_STATIC (12); +}; + struct KerxSubTableFormat0 { inline int get_kerning (hb_codepoint_t left, hb_codepoint_t right) const @@ -76,10 +92,11 @@ struct KerxSubTableFormat0 } protected: + KerxSubTableHeader header; BinSearchArrayOf - pairs; /* Sorted kern records. */ + pairs; /* Sorted kern records. */ public: - DEFINE_SIZE_ARRAY (16, pairs); + DEFINE_SIZE_ARRAY (28, pairs); }; struct KerxSubTableFormat1 @@ -104,10 +121,11 @@ struct KerxSubTableFormat1 } protected: + KerxSubTableHeader header; StateTable stateHeader; LOffsetTo > valueTable; public: - DEFINE_SIZE_STATIC (20); + DEFINE_SIZE_STATIC (32); }; struct KerxSubTableFormat2 @@ -168,18 +186,18 @@ struct KerxSubTableFormat2 }; protected: - HBUINT32 rowWidth; /* The width, in bytes, of a row in the table. */ + KerxSubTableHeader header; + HBUINT32 rowWidth; /* The width, in bytes, of a row in the table. */ LOffsetTo > - leftClassTable; /* Offset from beginning of this subtable to - * left-hand class table. */ + leftClassTable; /* Offset from beginning of this subtable to + * left-hand class table. */ LOffsetTo > - rightClassTable;/* Offset from beginning of this subtable to - * right-hand class table. */ - LOffsetTo - array; /* Offset from beginning of this subtable to - * the start of the kerning array. */ + rightClassTable;/* Offset from beginning of this subtable to + * right-hand class table. */ + LOffsetTo array; /* Offset from beginning of this subtable to + * the start of the kerning array. */ public: - DEFINE_SIZE_STATIC (16); + DEFINE_SIZE_STATIC (28); }; struct KerxSubTableFormat4 @@ -202,8 +220,9 @@ struct KerxSubTableFormat4 } protected: + KerxSubTableHeader header; public: - DEFINE_SIZE_STATIC (1); + DEFINE_SIZE_STATIC (12); }; struct KerxSubTableFormat6 @@ -231,23 +250,24 @@ struct KerxSubTableFormat6 } protected: - HBUINT32 flags; - HBUINT16 rowCount; - HBUINT16 columnCount; + KerxSubTableHeader header; + HBUINT32 flags; + HBUINT16 rowCount; + HBUINT16 columnCount; LOffsetTo > rowIndexTable; LOffsetTo > columnIndexTable; LOffsetTo > kerningArray; LOffsetTo > kerningVector; public: - DEFINE_SIZE_STATIC (24); + DEFINE_SIZE_STATIC (36); }; struct KerxTable { friend struct kerx; - inline unsigned int get_size (void) const { return length; } - inline unsigned int get_type (void) const { return coverage & SubtableType; } + inline unsigned int get_size (void) const { return u.header.length; } + inline unsigned int get_type (void) const { return u.header.coverage & SubtableType; } enum Coverage { @@ -281,19 +301,16 @@ struct KerxTable inline bool sanitize (hb_sanitize_context_t *c) const { TRACE_SANITIZE (this); - if (!length.sanitize (c) || - length < min_size || - !c->check_range (this, length)) + if (!u.header.sanitize (c) || + !c->check_range (this, u.header.length)) return_trace (false); return_trace (dispatch (c)); } protected: - HBUINT32 length; - HBUINT32 coverage; - HBUINT32 tupleCount; union { + KerxSubTableHeader header; KerxSubTableFormat0 format0; KerxSubTableFormat1 format1; KerxSubTableFormat2 format2; @@ -324,14 +341,14 @@ struct kerx { bool reverse; - if (table->coverage & (KerxTable::CrossStream | KerxTable::Variation)) + if (table->u.header.coverage & (KerxTable::CrossStream | KerxTable::Variation)) goto skip; /* We do NOT handle cross-stream or variation kerning. */ if (HB_DIRECTION_IS_VERTICAL (c->buffer->props.direction) != - bool (table->coverage & KerxTable::Vertical)) + bool (table->u.header.coverage & KerxTable::Vertical)) goto skip; - reverse = bool (table->coverage & KerxTable::Backwards) != + reverse = bool (table->u.header.coverage & KerxTable::Backwards) != HB_DIRECTION_IS_BACKWARD (c->buffer->props.direction); if (!c->buffer->message (c->font, "start kerx subtable %d", c->lookup_index)) diff --git a/src/hb-ot-kern-table.hh b/src/hb-ot-kern-table.hh index ccb666e8c..dab7a805f 100644 --- a/src/hb-ot-kern-table.hh +++ b/src/hb-ot-kern-table.hh @@ -191,6 +191,12 @@ struct KernSubTableFormat2 { inline int get_kerning (hb_codepoint_t left, hb_codepoint_t right, const char *end) const { + /* This subtable is disabled. It's not cleaer to me *exactly* where the offests are + * based from. I *think* they should be based from beginning of kern subtable wrapper, + * *NOT* "this". Since we know of no fonts that use this subtable, we are disabling + * it. Someday fix it and re-enable. Better yet, find fonts that use it... Meh, + * Windows doesn't implement it. Maybe just remove... */ + return 0; unsigned int l = (this+leftClassTable).get_class (left); unsigned int r = (this+rightClassTable).get_class (right); unsigned int offset = l + r; @@ -204,6 +210,7 @@ struct KernSubTableFormat2 inline bool sanitize (hb_sanitize_context_t *c) const { TRACE_SANITIZE (this); + return_trace (true); /* Disabled. See above. */ return_trace (rowWidth.sanitize (c) && leftClassTable.sanitize (c, this) && rightClassTable.sanitize (c, this) &&