Implement thousand-digit grouping under THND feature. #453

changes/3.0.0-rc.4.md

@@ -2,4 +2,5 @@
  * Add large brackets (U+239B ... U+23AD) and extensible integral symbols (U+2320, U+2321, U+23AE).
  * Add arrow U+21DE, U+21DF, U+2908, U+2909.
  * Add logical symbol U+22A9, U+22AA, U+22AB, U+22AE, U+22AF.
- * Cancelled ligation around regex look-around.
+ * Cancelled ligation around regex look-around.
+ * Implement thousand-digit grouping under `THND` feature.

glyphs/autobuild-transformed.ptl

@@ -536,3 +536,25 @@ glyph-block Autobuild-Transformed : begin
 		list 0x225F "equal" {"question"}
 	if [not recursive] : createAccentedEquals 8 0.3 : list
 		list 0x225d "equal" {"d" "e" "f"}
+
+	define [createGroupedDigits shrink crowd numberEntries] : begin
+		define numberGlyphIDs {}
+		foreach [gid : items-of numberEntries] : if glyphs.(gid) : begin
+			numberGlyphIDs.push gid
+			if glyphs.(gid).featureSelector : begin
+				foreach [{k v} : pairs-of glyphs.(gid).featureSelector] : begin
+					numberGlyphIDs.push v
+
+		local derivedFont : Thinner numberGlyphIDs shrink crowd
+		foreach [nd : items-of {0 1 2 3 4 5 6}]
+			foreach [gid : items-of numberGlyphIDs] : create-glyph (gid + ".nd" + nd) : glyph-construction
+				include glyphs.(gid)
+				define underlineExt : WIDTH * 0.4
+				if (nd >= 3 && nd <= 5) : include : intersection
+					HBarBottom (MIDDLE - underlineExt) (MIDDLE + underlineExt) (DESCENDER * 0.75) [adviceBlackness 4]
+					begin glyphs.'denseShade.hwid'
+
+	if [not recursive] : createGroupedDigits 0.9 3.0 {
+		'zero.lnum' 'one.lnum' 'two.lnum' 'three.lnum' 'four.lnum'
+		'five.lnum' 'six.lnum' 'seven.lnum' 'eight.lnum' 'nine.lnum'
+	}

glyphs/common-shapes.ptl

@@ -667,8 +667,9 @@ glyph-block CommonShapes : begin
 			forkedPara.diversityM  = 1
 		return : Fork glyphs forkedPara
 
-	define [Thinner glyphs p] : begin
+	define [Thinner glyphs p crowd] : begin
 		local forkedPara : Object.create para
+		forkedPara.stroke = [adviceBlackness : fallback crowd 1]
 		forkedPara.width = WIDTH * p
 		forkedPara.accentx = ACCENTX * p
 		forkedPara.jut = JUT * p

glyphs/symbol-mosaic.ptl

@@ -345,6 +345,11 @@ glyph-block Symbol-Mosaic : begin
 				include : Shade 4 FillLight
 				save [MangleName 'lightShade'] [MangleUnicode 0x2591]
 
+			sketch # denseShade
+				set-width MosaicWidth
+				include : Shade 16 FillHeavy
+				save [MangleName 'denseShade']
+
 			define [MediumShade unicode bits] : sketch
 				set-width MosaicWidth
 				include : Shade 8 FillMedium : PatternPolygon22 bits

otl/gsub-thousands.ptl

@@ -0,0 +1,52 @@
+import [add-common-feature add-feature add-lookup ChainRuleBuilder] from "./table-util"
+
+define-operator "~>" 880 'right' : syntax-rules
+	`(@l ~> @r) `{.left @l .right @r}
+
+export : define [buildGsubThousands sink glyphs] : begin
+	define Thousand : add-feature sink 'THND'
+	define chain-rule : ChainRuleBuilder sink
+	define numberEntries {
+		'zero.lnum' 'one.lnum' 'two.lnum' 'three.lnum' 'four.lnum'
+		'five.lnum' 'six.lnum' 'seven.lnum' 'eight.lnum' 'nine.lnum'
+	}
+	define numberGlyphIDs {}
+	foreach [gid : items-of numberEntries] : if glyphs.(gid) : begin
+		numberGlyphIDs.push gid
+		if glyphs.(gid).featureSelector : begin
+			foreach [{k v} : pairs-of glyphs.(gid).featureSelector] : begin
+				numberGlyphIDs.push v
+
+	define [nd s] : numberGlyphIDs.map : lambda [x] "\(x).nd\(s)"
+
+	define lookupThousand1 : add-lookup sink : object
+		.type 'gsub_chaining'
+		.subtables : list
+			chain-rule ({'period'} ~> null) (numberGlyphIDs ~> [nd 2]) (numberGlyphIDs ~> null) (numberGlyphIDs ~> null)
+			chain-rule ([nd 2] ~> null) (numberGlyphIDs ~> [nd 1])
+			chain-rule ([nd 1] ~> null) (numberGlyphIDs ~> [nd 6])
+			chain-rule ([nd 6] ~> null) (numberGlyphIDs ~> [nd 5])
+			chain-rule ([nd 5] ~> null) (numberGlyphIDs ~> [nd 4])
+			chain-rule ([nd 4] ~> null) (numberGlyphIDs ~> [nd 3])
+			chain-rule ([nd 3] ~> null) (numberGlyphIDs ~> [nd 2])
+
+	define lookupThousand2 : add-lookup sink : object
+		.type 'gsub_chaining'
+		.subtables : list
+			chain-rule (numberGlyphIDs ~> [nd 0]) (numberGlyphIDs ~> null) (numberGlyphIDs ~> null) (numberGlyphIDs ~> null)
+			chain-rule ([nd 0] ~> null) (numberGlyphIDs ~> [nd 0])
+
+	define lookupThousand3 : add-lookup sink : object
+		.type 'gsub_reverse'
+		.subtables : list
+			object [match {[nd 0] [nd 0]}] [to [nd 1]] [inputIndex 0]
+			object [match {[nd 0] [nd 1]}] [to [nd 2]] [inputIndex 0]
+			object [match {[nd 0] [nd 2]}] [to [nd 3]] [inputIndex 0]
+			object [match {[nd 0] [nd 3]}] [to [nd 4]] [inputIndex 0]
+			object [match {[nd 0] [nd 4]}] [to [nd 5]] [inputIndex 0]
+			object [match {[nd 0] [nd 5]}] [to [nd 6]] [inputIndex 0]
+			object [match {[nd 0] [nd 6]}] [to [nd 1]] [inputIndex 0]
+
+
+	Thousand.lookups.push lookupThousand1 lookupThousand2 lookupThousand3
+	add-common-feature sink Thousand

otl/index.ptl

@@ -10,6 +10,7 @@ import [buildCCMP] from './gsub-ccmp'
 import [buildPairFeature] from './gsub-pairing'
 import [buildCVSS] from './gsub-cv-ss'
 import [buildLOCL] from './gsub-locl'
+import [buildGsubThousands] from './gsub-thousands'
 import [buildMarkMkmk] from "./gpos-mark-mkmk"
 import [BuildCompatLigatures] from './compat-ligature'
 
@@ -39,6 +40,7 @@ define [buildGSUB para glyphs glyphList markGlyphs] : begin
 		buildLigations gsub plm glyphs
 
 	buildCVSS gsub para glyphList
+	buildGsubThousands gsub glyphs
 
 	set gsub.lookupOrder : topsort gsub.lookupDep
 	return gsub