Add ligation set for chaining number signs (#894).

changes/5.1.0.md

@@ -0,0 +1 @@
+ * Add ligation set for chaining number signs (#894).

font-src/glyphs/symbol/punctuation.ptl

@@ -1061,52 +1061,74 @@ glyph-block Symbol-Punctuation-Slashes-And-Number-Sign : begin
 		define nsBot : mix SymbolMid ParenBot 0.85
 		define fine : AdviceStroke 3.5
 
-		define pFineOpen (1 / 8)
+		define [HspT l r] : ((r - l) - (fine * 2 * HVContrast)) * 0.3
-		define l : SB - fine / 2
-		define r : RightSB + fine / 2
-		define hsp : ((r - l) - (fine * 2 * HVContrast)) * 0.3
 
-		define [UprightHBars] : union
+		define [UprightHBars lx l r p] : union
-			HBar l r [mix nsTop nsBot 0.3]
+			HBar lx r [mix nsTop nsBot 0.3]
-			HBar l r [mix nsTop nsBot 0.7]
+			HBar lx r [mix nsTop nsBot 0.7]
-		define [UprightVBars p] : union
-			VBarLeft  (l + hsp + p * fine) nsBot nsTop fine
-			VBarRight (r - hsp - p * fine) nsBot nsTop fine
 
+		define [UprightHBarsOpen lx l r p] : begin
+			define hsp : HspT l r
+			return : difference
+				UprightHBars lx l r p
+				Rect nsTop nsBot
+					l + hsp + fine * (0.5 + p)
+					r - hsp - fine * (0.5 + p)
 
-		create-glyph 'numberSign.upright' : union
+		define [UprightVBars lx l r p] : begin
-			UprightHBars
+			define hsp : HspT l r
-			UprightVBars 0
+			return : union
+				VBarLeft  (l + hsp + p * fine) nsBot nsTop fine
+				VBarRight (r - hsp - p * fine) nsBot nsTop fine
 
-		create-glyph 'numberSign.uprightOpen' : union
+		define [SlantedDim l r] : begin
-			UprightVBars pFineOpen
+			define hsp : HspT l r
-			difference
+			define x : hsp + fine / 2 * HVContrast
-				UprightHBars
+			define w : (r - l) * 0.15
-				Rect nsTop nsBot (l + hsp + fine * (0.5 + pFineOpen)) (r - hsp - fine * (0.5 + pFineOpen))
+			define shift : w / 3
+			return : object hsp x w shift
 
-		define x : hsp + fine / 2 * HVContrast
+		define [SlantedHBars lx l r p] : begin
-		define w : (r - l) * 0.15
+			define [object shift] : SlantedDim l r
-		define shift : w / 3
+			return : union
-		define [SlantedHBars] : union
+				HBar (lx + shift) (r + shift) [mix nsTop nsBot 0.3]
-			HBar (l + shift) (r + shift) [mix nsTop nsBot 0.3]
+				HBar (lx - shift) (r - shift) [mix nsTop nsBot 0.7]
-			HBar (l - shift) (r - shift) [mix nsTop nsBot 0.7]
+		define [SlantedHBarsOpen lx l r p] : begin
-		define [SlantedVBars p] : union
+			define [object x w] : SlantedDim l r
-			SlashShape (l + x - w + p * fine) (l + x + w + p * fine) nsTop nsBot fine
+			return : difference
-			SlashShape (r - x - w - p * fine) (r - x + w - p * fine) nsTop nsBot fine
+				SlantedHBars lx l r p
-
-		create-glyph 'numberSign.slanted' : union [SlantedHBars] [SlantedVBars 0]
-		create-glyph 'numberSign.slantedOpen' : union
-			SlantedVBars pFineOpen
-			difference
-				SlantedHBars
 				spiro-outline
-					corner (l + x + w + pFineOpen * fine) nsTop
+					corner (l + x + w + p * fine) nsTop
-					corner (r - x + w - pFineOpen * fine) nsTop
+					corner (r - x + w - p * fine) nsTop
-					corner (r - x - w - pFineOpen * fine) nsBot
+					corner (r - x - w - p * fine) nsBot
-					corner (l + x - w + pFineOpen * fine) nsBot
+					corner (l + x - w + p * fine) nsBot
+		define [SlantedVBars lx l r p] : begin
+			define [object x w] : SlantedDim l r
+			return : union
+				SlashShape (l + x - w + p * fine) (l + x + w + p * fine) nsTop nsBot fine
+				SlashShape (r - x - w - p * fine) (r - x + w - p * fine) nsTop nsBot fine
 
+		define NumberSignConfig : object
+			upright     { UprightHBars     UprightVBars  0      }
+			uprightOpen { UprightHBarsOpen UprightVBars (1 / 8) }
+			slanted     { SlantedHBars     SlantedVBars  0      }
+			slantedOpen { SlantedHBarsOpen SlantedVBars (1 / 8) }
+
+		foreach { suffix { FHBars FVBars p } } [Object.entries NumberSignConfig] : do
+
+			define l : SB - fine / 2
+			define r : RightSB + fine / 2
+
+			create-glyph "numberSign.\(suffix)" : union
+				FHBars l l r p
+				FVBars l l r p
+
+			create-glyph "numberSign.jr.\(suffix)" : union
+				FHBars (r - Width) l r p
+				FVBars (r - Width) l r p
 
 		select-variant 'numberSign' '#'
+		select-variant 'numberSign.jr' (follow -- 'numberSign')
 
 
 glyph-block Symbol-Punctuation-Dashes : begin

font-src/otl/gsub-ligation.ptl

@@ -42,10 +42,7 @@ define [buildLigationsImpl sink para featureName mappedFeature rankedLookups] :
 	define regexLookAround [less.concat hyphen equal exclam greater anyBar]
 
 	define [acops]  {'less' 'greater' 'hyphen' 'equal' 'plus'}
-	define [acskip] {
+	define [acskip] {'slash' 'bar' 'at' 'ampersand' 'percent' 'numberSign'}
-		'slash' 'bar' 'at' 'ampersand' 'percent'
-		'numberSign' 'numberSign.upright' 'numberSign.slanted'
-	}
 
 	local ligationLookupName : 'lig_' + featureName + '{' + mappedFeature + '}'
 
@@ -276,6 +273,12 @@ define [buildLigationsImpl sink para featureName mappedFeature rankedLookups] :
 				{'underscore' 'underscore.jr'} ~> look-around
 				{'underscore'} ~> {'underscore.jr'}
 
+	do "Number sign chains" : if [hasLG 'connected-number-sign'] : begin
+		CreateLigationLookup : list
+			chain-rule
+				{'numberSign' 'numberSign.jr'} ~> look-around
+				{'numberSign'} ~> {'numberSign.jr'}
+
 	do "triangles" : if [hasLG 'trig'] : begin
 		CreateLigationLookup : list
 			chain-rule # <|

params/ligation-set.toml

@@ -120,7 +120,7 @@ desc = 'Enable ligation for `<!--` and `<!---`'
 
 [simple.colon-greater-as-colon-arrow]
 ligGroup = "colon-greater"
-desc = 'Transform `:>` into `:` and a narrow arrow.'
+desc = 'Transform `:>` into `:` and a narrow arrow'
 
 [simple.brace-bar]
 ligGroup = 'brace-bar'
@@ -134,6 +134,10 @@ desc = 'Enable ligation for `[|` and `|]`'
 ligGroup = 'connected-underscore'
 desc = 'Make contiguous underscores (like `__`) connected'
 
+[simple.connected-number-sign]
+ligGroup = 'connected-number-sign'
+desc = 'Make contiguous number signs (like `##`) connected'
+
 ###################################################################################################
 
 # This feature is on by default by many software
@@ -146,7 +150,7 @@ readmeDesc = 'Inherit default ligation set'
 
 [composite.dlig]
 tag     = 'dlig'
-buildup = ['center-ops', 'arrow', 'html-comment', 'trig', 'arrow2', 'llgg', 'eqeq', 'exeq', 'ineq', 'ltgt-diamond', 'plusplus', 'kern-dotty', 'dot-as-operator', 'logic', 'brst', 'brace-bar', 'brack-bar', 'connected-underscore']
+buildup = ['center-ops', 'arrow', 'html-comment', 'trig', 'arrow2', 'llgg', 'eqeq', 'exeq', 'ineq', 'ltgt-diamond', 'plusplus', 'kern-dotty', 'dot-as-operator', 'logic', 'brst', 'brace-bar', 'brack-bar', 'connected-underscore', 'connected-number-sign']
 brief   = 'Discretionary'
 desc    = 'Discretionary ligatures'