diff --git a/pitfall/fontkit/gsub-processor.rkt b/pitfall/fontkit/gsub-processor.rkt index 67889ffb..1a93da6a 100644 --- a/pitfall/fontkit/gsub-processor.rkt +++ b/pitfall/fontkit/gsub-processor.rkt @@ -83,33 +83,6 @@ https://github.com/mbutterick/fontkit/blob/master/src/opentype/GSUBProcessor.js (set-field! isLigated ligatureGlyph #t) (set-field! substituted ligatureGlyph #t) - ;; From Harfbuzz: - ;; - If it *is* a mark ligature, we don't allocate a new ligature id, and leave - ;; the ligature to keep its old ligature id. This will allow it to attach to - ;; a base ligature in GPOS. Eg. if the sequence is: LAM,LAM,SHADDA,FATHA,HEH, - ;; and LAM,LAM,HEH for a ligature, they will leave SHADDA and FATHA with a - ;; ligature id and component value of 2. Then if SHADDA,FATHA form a ligature - ;; later, we don't want them to lose their ligature id/component, otherwise - ;; GPOS will fail to correctly position the mark ligature on top of the - ;; LAM,LAM,HEH ligature. See https://bugzilla.gnome.org/show_bug.cgi?id=676343 - ;; - ;; - If a ligature is formed of components that some of which are also ligatures - ;; themselves, and those ligature components had marks attached to *their* - ;; components, we have to attach the marks to the new ligature component - ;; positions! Now *that*'s tricky! And these marks may be following the - ;; last component of the whole sequence, so we should loop forward looking - ;; for them and update them. - ;; - ;; Eg. the sequence is LAM,LAM,SHADDA,FATHA,HEH, and the font first forms a - ;; 'calt' ligature of LAM,HEH, leaving the SHADDA and FATHA with a ligature - ;; id and component == 1. Now, during 'liga', the LAM and the LAM-HEH ligature - ;; form a LAM-LAM-HEH ligature. We need to reassign the SHADDA and FATHA to - ;; the new ligature with a component value of 2. - ;; - ;; This in fact happened to a font... See - ;; https://bugzilla.gnome.org/show_bug.cgi?id=437633 - - (define isMarkLigature (and (· curGlyph isMark) (for/and ([match-idx (in-list matched)]) @@ -158,5 +131,11 @@ https://github.com/mbutterick/fontkit/blob/master/src/opentype/GSUBProcessor.js (report* (for/list ([g (· this glyphs)]) (· g id)) (· this glyphIterator index)) #t)] [else #f])] + [(5) ;; Contextual Substitution + (send this applyContext table)] + [(6) ;; Chaining Contextual Substitution + (send this applyChainingContext table)] + [(7) ;; Extension Substitution + (send this applyLookup (· table lookupType) (· table extension))] [else (error 'unimplemented-gsub-lookup)]))) diff --git a/pitfall/fontkit/ot-processor.rkt b/pitfall/fontkit/ot-processor.rkt index c564d00b..25b91a1c 100644 --- a/pitfall/fontkit/ot-processor.rkt +++ b/pitfall/fontkit/ot-processor.rkt @@ -33,7 +33,7 @@ https://github.com/mbutterick/fontkit/blob/master/src/opentype/OTProcessor.js (for*/first ([entry (in-list (· this table scriptList))] [s (in-list scripts)] #:when (eq? (· entry tag) s)) - entry)))) + entry)))) (define/public (selectScript [script #f] [language #f]) @@ -57,9 +57,9 @@ https://github.com/mbutterick/fontkit/blob/master/src/opentype/OTProcessor.js (when (and (not language) (not (equal? language (· this languageTag)))) (for/first ([lang (in-list (· this script langSysRecords))] #:when (equal? (· lang tag) language)) - (set-field! language this (· lang langSys)) - (set-field! languageTag this (· lang tag)) - (set! changed #t))) + (set-field! language this (· lang langSys)) + (set-field! languageTag this (· lang tag)) + (set! changed #t))) (when (not (· this language)) (set-field! language this (· this script defaultLangSys))) @@ -69,8 +69,8 @@ https://github.com/mbutterick/fontkit/blob/master/src/opentype/OTProcessor.js (set-field! features this (mhash)) (when (· this language) (for ([featureIndex (in-list (· this language featureIndexes))]) - (define record (list-ref (· this table featureList) featureIndex)) - (dict-set! (· this features) (· record tag) (· record feature))))))) + (define record (list-ref (· this table featureList) featureIndex)) + (dict-set! (· this features) (· record tag) (· record feature))))))) (define/public (lookupsForFeatures [userFeatures empty] [exclude #f]) @@ -80,10 +80,10 @@ https://github.com/mbutterick/fontkit/blob/master/src/opentype/OTProcessor.js #:when feature [lookupIndex (in-list (· feature lookupListIndexes))] #:unless (and exclude (index-of exclude lookupIndex))) - #;(report*/file tag lookupIndex) - (mhasheq 'feature tag - 'index lookupIndex - 'lookup (send (· this table lookupList) get lookupIndex))) + #;(report*/file tag lookupIndex) + (mhasheq 'feature tag + 'index lookupIndex + 'lookup (send (· this table lookupList) get lookupIndex))) < #:key (λ (i) (· i index)))) @@ -103,29 +103,29 @@ https://github.com/mbutterick/fontkit/blob/master/src/opentype/OTProcessor.js (set-field! glyphIterator this (+GlyphIterator glyphs)) (for* ([lookup-entry (in-list lookups)]) - (define feature (· lookup-entry feature)) - (define lookup (· lookup-entry lookup)) + (define feature (· lookup-entry feature)) + (define lookup (· lookup-entry lookup)) (report 'resetting-iterator) - (send (· this glyphIterator) reset (· lookup flags)) + (send (· this glyphIterator) reset (· lookup flags)) - (while (< (or (· this glyphIterator index) 0) (length (· this glyphs))) - (report 'start-while++++++++++++++++++) - (report (length (· this glyphs)) 'glyphs-length-top) - (report (for/list ([g (· this glyphs)]) (· g id)) 'gids-top) - (report (· this glyphIterator index) giterator-idx-top) - (report* feature (· this glyphIterator cur id) (· this glyphIterator cur features)) - (report (dict-has-key? (· this glyphIterator cur features) feature)) - (cond - [(not (dict-has-key? (· this glyphIterator cur features) feature)) - (send (· this glyphIterator) next)] - [else - (report/file 'start-lookup-branch=================) - (report* (for/list ([g (· this glyphs)]) (· g id)) (for/list ([g (· this glyphIterator glyphs)]) (· g id)) (for/list ([g glyphs]) (· g id)) (· this glyphIterator index) (· this glyphIterator cur id) (· this glyphIterator peekIndex)) - (for/or ([table (in-list (· lookup subTables))]) - (send this applyLookup (· lookup lookupType) table)) - (report 'incrementing-iterator-at-bottom) - (send (· this glyphIterator) next) - (report* (· this glyphIterator cur) (· this glyphIterator index))])))) + (while (< (or (· this glyphIterator index) 0) (length (· this glyphs))) + (report 'start-while++++++++++++++++++) + (report (length (· this glyphs)) 'glyphs-length-top) + (report (for/list ([g (· this glyphs)]) (· g id)) 'gids-top) + (report (· this glyphIterator index) giterator-idx-top) + (report* feature (· this glyphIterator cur id) (· this glyphIterator cur features)) + (report (dict-has-key? (· this glyphIterator cur features) feature)) + (cond + [(not (dict-has-key? (· this glyphIterator cur features) feature)) + (send (· this glyphIterator) next)] + [else + (report/file 'start-lookup-branch=================) + (report* (for/list ([g (· this glyphs)]) (· g id)) (for/list ([g (· this glyphIterator glyphs)]) (· g id)) (for/list ([g glyphs]) (· g id)) (· this glyphIterator index) (· this glyphIterator cur id) (· this glyphIterator peekIndex)) + (for/or ([table (in-list (· lookup subTables))]) + (send this applyLookup (· lookup lookupType) table)) + (report 'incrementing-iterator-at-bottom) + (send (· this glyphIterator) next) + (report* (· this glyphIterator cur) (· this glyphIterator index))])))) (abstract applyLookup) @@ -139,14 +139,14 @@ https://github.com/mbutterick/fontkit/blob/master/src/opentype/OTProcessor.js [(1) (index-of (· coverage glyphs) glyph)] [(2) (for/first ([range (in-list (· coverage rangeRecords))] #:when (<= (· range start) glyph (· range end))) - (+ (· range startCoverageIndex) glyph (- (· range start))))] + (+ (· range startCoverageIndex) glyph (- (· range start))))] [else #f]) -1)) (define/public (match sequenceIndex sequence fn [matched #f]) (define pos (· this glyphIterator index)) (define glyph (send (· this glyphIterator) increment sequenceIndex)) (define idx 0) - (report* (list-ref sequence idx) (· glyph id)) + (report*/file (list-ref sequence idx) glyph (· glyph id)) (while (and (< idx (length sequence)) glyph (fn (list-ref sequence idx) (· glyph id))) (report* 'in-match-loop idx (· glyph id)) @@ -163,6 +163,9 @@ https://github.com/mbutterick/fontkit/blob/master/src/opentype/OTProcessor.js (define/public (sequenceMatchIndices sequenceIndex sequence) (send this match sequenceIndex sequence (λ (component glyph) (= component glyph)) empty)) + (define/public (coverageSequenceMatches sequenceIndex sequence) + (send this match sequenceIndex sequence (λ (coverage glyph) (>= (send this coverageIndex coverage glyph) 0)))) + (define/public (getClassID glyph classDef) (or (case (· classDef version) @@ -174,6 +177,70 @@ https://github.com/mbutterick/fontkit/blob/master/src/opentype/OTProcessor.js [(2) (for/first ([range (in-list (· classDef classRangeRecord))] #:when (<= (· range start) glyph (· range end))) - (· range class))]) - 0))) + (· range class))]) + 0)) + + (define/public (applyContext table) + (report/file 'otproc:applyContext) + (case (· table version) + [(1) (define index (send this coverageIndex (· table coverage))) + (cond + [(= index -1) #f] + [else (define set (list-ref (· table ruleSets) index)) + (for/first ([rule (in-list set)] + #:when (send this sequenceMatches 1 (· rule input))) + (send this applyLookupList (· rule lookupRecords)))])] + [(2) (cond + [(= (send this coverageIndex (· table coverage)) -1) #f] + [else (define index + (send this getClassID (· this glyphIterator cur id) (· table classDef))) + (cond + [(- index -1) #f] + [else (define set (list-ref (· table classSet) index)) + (for/first ([rule (in-list set)] + #:when (send this sequenceMatches 1 (· rule classes) (· table classDef))) + (send this applyLookupList (· rule lookupRecords)))])])] + + [(3) (and (send this coverageSequenceMatches 0 (· table coverages)) + (send this applyLookupList (· table lookupRecords)))] + [else #f])) + +(define/public (applyChainingContext table) + (report/file 'otproc:applyChainingContext) + (case (· table version) + [(1) + (report 'case-1) + (define index (send this coverageIndex (· table coverage))) + (cond + [(= index -1) #f] + [else (define set (list-ref (· table chainRuleSets) index)) + (for/first ([rule (in-list set)] + #:when (and (send this sequenceMatches (- (length (· rule backtrack)) (· rule backtrack))) + (send this sequenceMatches 1 (· rule input)) + (send this sequenceMatches (add1 (length (· rule input))) (· rule lookahead)))) + (send this applyLookupList (· rule lookupRecords)))])] + [(2) + (report 'case-2) + (cond + [(= -1 (send this coverageIndex (· table coverage))) #f] + [else (define index (send this getClassID (· this glyphIterator cur id) (· table inputClassDef))) + (define rules (list-ref (· table chainClassSet) index)) + (cond + [(not rules) #f] + [else (for/first ([rule (in-list rules)] + #:when (and (send this classSequenceMatches (- (length (· rule backtrack)) (· rule backtrack) (· table backtrackClassDef))) + (send this classSequenceMatches 1 (· rule input) (· table inputClassDef)) + (send this classSequenceMatches (add1 (length (· rule input))) (· rule lookahead) (· table lookaheadClassDef)))) + (send this applyLookupList (· rule lookupRecords)))])])] + [(3) + (report 'case-3) + (and + (send this coverageSequenceMatches (- (· table backtrackGlyphCount)) (· table backtrackCoverage)) + (send this coverageSequenceMatches 0 (· table inputCoverage)) + (send this coverageSequenceMatches (· table inputGlyphCount) (· table lookaheadCoverage)) + (send this applyLookupList (· table lookupRecords)))] + [else #f])) + + ) + \ No newline at end of file