[PATCH 6/7] dwrite: Implement chaining contextual substitution of format 1.
Nikolay Sivov
nsivov at codeweavers.com
Fri May 29 11:01:08 CDT 2020
Signed-off-by: Nikolay Sivov <nsivov at codeweavers.com>
---
dlls/dwrite/opentype.c | 63 ++++++++++++++++++++++++++++++++++++++++--
1 file changed, 60 insertions(+), 3 deletions(-)
diff --git a/dlls/dwrite/opentype.c b/dlls/dwrite/opentype.c
index 198da43f2cd..5114e900df6 100644
--- a/dlls/dwrite/opentype.c
+++ b/dlls/dwrite/opentype.c
@@ -618,6 +618,12 @@ struct ot_gsub_chaincontext_subst_format1
UINT16 rulesets[1];
};
+struct ot_gsub_ruleset
+{
+ UINT16 count;
+ UINT16 offsets[1];
+};
+
struct ot_feature
{
WORD feature_params;
@@ -3525,6 +3531,11 @@ struct ot_gdef_mark_glyph_sets
DWORD offsets[1];
};
+static BOOL opentype_match_glyph_func(UINT16 glyph, UINT16 glyph_data, const struct match_data *data)
+{
+ return glyph == glyph_data;
+}
+
static BOOL opentype_match_coverage_func(UINT16 glyph, UINT16 glyph_data, const struct match_data *data)
{
const struct match_context *mc = data->mc;
@@ -5139,7 +5150,9 @@ static BOOL opentype_layout_apply_gsub_chain_context_substitution(struct scripts
{
struct match_context mc = { .context = context, .mask = lookup->mask };
const struct dwrite_fonttable *table = &context->table->table;
- unsigned int coverage_index = GLYPH_NOT_COVERED;
+ unsigned int i, coverage_index = GLYPH_NOT_COVERED, count, offset;
+ unsigned int backtrack_count, input_count, lookahead_count, lookup_count;
+ const UINT16 *backtrack, *lookahead, *input, *lookup_records;
UINT16 glyph, format, coverage;
BOOL ret = FALSE;
@@ -5149,6 +5162,8 @@ static BOOL opentype_layout_apply_gsub_chain_context_substitution(struct scripts
if (format == 1)
{
+ const struct ot_gsub_ruleset *ruleset;
+
coverage = table_read_be_word(table, subtable_offset +
FIELD_OFFSET(struct ot_gsub_chaincontext_subst_format1, coverage));
@@ -5156,7 +5171,49 @@ static BOOL opentype_layout_apply_gsub_chain_context_substitution(struct scripts
if (coverage_index == GLYPH_NOT_COVERED)
return FALSE;
- WARN("Chaining contextual substitution (1) is not supported.\n");
+ count = table_read_be_word(table, subtable_offset + FIELD_OFFSET(struct ot_gsub_chaincontext_subst_format1,
+ ruleset_count));
+ if (coverage_index >= count)
+ return FALSE;
+
+ offset = table_read_be_word(table, subtable_offset + FIELD_OFFSET(struct ot_gsub_chaincontext_subst_format1,
+ rulesets[coverage_index]));
+ offset += subtable_offset;
+
+ count = table_read_be_word(table, offset);
+ ruleset = table_read_ensure(table, offset, count * sizeof(ruleset->offsets));
+
+ mc.match_func = opentype_match_glyph_func;
+ for (i = 0; i < count; ++i)
+ {
+ unsigned int rule_offset = offset + GET_BE_WORD(ruleset->offsets[i]);
+
+ backtrack_count = table_read_be_word(table, rule_offset);
+ rule_offset += 2;
+ backtrack = table_read_ensure(table, rule_offset, backtrack_count * sizeof(*backtrack));
+ rule_offset += backtrack_count * sizeof(*backtrack);
+
+ input_count = table_read_be_word(table, rule_offset);
+ rule_offset += 2;
+ input = table_read_ensure(table, rule_offset, input_count * sizeof(*input));
+ rule_offset += input_count * sizeof(*input);
+
+ lookahead_count = table_read_be_word(table, rule_offset);
+ rule_offset += 2;
+ lookahead = table_read_ensure(table, rule_offset, lookahead_count * sizeof(*lookahead));
+ rule_offset += lookahead_count * sizeof(*lookahead);
+
+ lookup_count = table_read_be_word(table, rule_offset);
+ rule_offset += 2;
+ lookup_records = table_read_ensure(table, rule_offset, lookup_count * 2 * sizeof(*lookup_records));
+
+ /* First applicable rule is used. */
+ if (opentype_layout_apply_gsub_chain_context_lookup(backtrack_count, backtrack, input_count, input, lookahead_count,
+ lookahead, lookup_count, lookup_records, &mc))
+ {
+ return TRUE;
+ }
+ }
}
else if (format == 2)
{
@@ -5174,7 +5231,7 @@ static BOOL opentype_layout_apply_gsub_chain_context_substitution(struct scripts
unsigned int backtrack_count, input_count, lookahead_count, lookup_count;
const UINT16 *backtrack, *lookahead, *input, *lookup_records;
- unsigned int offset = subtable_offset + 2 /* format */;
+ offset = subtable_offset + 2 /* format */;
backtrack_count = table_read_be_word(table, offset);
offset += 2;
--
2.26.2
More information about the wine-devel
mailing list