From 990d5a9a887802b2f2490f946f5d6aac4e2fff5f Mon Sep 17 00:00:00 2001
From: Belleve Invis <belleve@typeof.net>
Date: Wed, 27 May 2020 03:33:41 -0700
Subject: [PATCH] Add `f` with straight tail (`v-f-straight-tailed`, `VXAD`,
 #519).

---
 changes/3.1.0.md                 |  3 +-
 glyphs/letters-unified-basic.ptl |  7 +++++
 otl/gsub-ccmp.ptl                |  7 ++++-
 otl/gsub-cv-ss.ptl               |  6 +++-
 otl/gsub-ligation.ptl            |  4 ++-
 otl/gsub-locl.ptl                | 12 +++++---
 otl/gsub-pairing.ptl             |  5 +++-
 otl/gsub-thousands.ptl           |  7 +++--
 otl/index.ptl                    | 15 ++++++++--
 otl/table-util.ptl               | 47 ++++++++++++++++++++++----------
 variants.toml                    | 12 ++++++--
 11 files changed, 94 insertions(+), 31 deletions(-)

diff --git a/changes/3.1.0.md b/changes/3.1.0.md
index d723b10644..7f24330eea 100644
--- a/changes/3.1.0.md
+++ b/changes/3.1.0.md
@@ -14,4 +14,5 @@
  * Fix broken long ligature at beginning of line in macOS TextEdit (#548).
  * Add `v-eszet-longs-s-lig` (#455).
  * Make `cv##` and `ss##` features work on enclosed/braced/superscript/subscript letters (#516).
- * Add playback symbols.
\ No newline at end of file
+ * Add playback symbols.
+ * Add `f` with straight tail (`v-f-straight-tailed`, `VXAD`, #519).
diff --git a/glyphs/letters-unified-basic.ptl b/glyphs/letters-unified-basic.ptl
index 8b2a15de61..83a8f6bdf2 100644
--- a/glyphs/letters-unified-basic.ptl
+++ b/glyphs/letters-unified-basic.ptl
@@ -4074,6 +4074,7 @@ glyph-block LetterUnified-Basic : begin
 		sketch # f.straight
 			local fovershoot2 (O * 2)
 			include MarkSet.b
+
 			local barleft : [mix SB RightSB 0.35] - Stroke * 0.25 * HVContrast
 			include : dispiro
 				widths.lhs
@@ -4099,6 +4100,11 @@ glyph-block LetterUnified-Basic : begin
 						curl ([mix SB RightSB 0.875] + HalfStroke * TanSlope) 0
 					save 'f.serifed'
 
+				branch
+					include MarkSet.if
+					include : VBarLeft barleft 0 (Descender * 0.9)
+					save 'f.straightTailed'
+
 			branch
 				include : dispiro
 					widths.rhs
@@ -4144,6 +4150,7 @@ glyph-block LetterUnified-Basic : begin
 
 		turned 'turnf.straight' nothing 'f.straight' Middle (XH / 2) MarkSet.p
 		turned 'turnf.serifed' nothing 'f.serifed' Middle (XH / 2) MarkSet.p
+		turned 'turnf.straightTailed' nothing 'f.straightTailed' Middle (XH / 2) MarkSet.p
 		turned 'turnf.narrow' nothing 'f.narrow' dfNarrowF.middle (XH / 2) dfNarrowF.markSet.p
 		turned 'turnf.tailed' nothing 'f.tailed' Middle (XH / 2) MarkSet.p
 		select-variant 'turnf' 0x25F (follow -- 'f')
diff --git a/otl/gsub-ccmp.ptl b/otl/gsub-ccmp.ptl
index 122e15db26..0e5db895a9 100644
--- a/otl/gsub-ccmp.ptl
+++ b/otl/gsub-ccmp.ptl
@@ -1,10 +1,13 @@
-import [add-common-feature add-feature add-lookup ChainRuleBuilder] from "./table-util"
+import [add-common-feature add-feature add-lookup ChainRuleBuilder BeginLookupBlock EndLookupBlock] from "./table-util"
 import [Dotless] from "../support/gr"
+extern Set
 
 define-operator "~>" 880 'right' : syntax-rules
 	`(@l ~> @r) `{.left @l .right @r}
 
 export : define [buildCCMP sink glyphs markGlyphs] : begin
+	local rec : BeginLookupBlock sink
+
 	define ccmp : add-feature sink 'ccmp'
 	define {chain-rule} : ChainRuleBuilder sink
 
@@ -187,3 +190,5 @@ export : define [buildCCMP sink glyphs markGlyphs] : begin
 	sink.lookupDep.push {lookupCcmp-ToneSandhiStart lookupCcmp-ToneSandhiMid}
 	sink.lookupDep.push {lookupCcmp-ToneSandhiMid lookupCcmp-ToneSandhiEnd}
 	add-common-feature sink ccmp
+
+	EndLookupBlock rec sink
\ No newline at end of file
diff --git a/otl/gsub-cv-ss.ptl b/otl/gsub-cv-ss.ptl
index 603b675847..9bb966dabd 100644
--- a/otl/gsub-cv-ss.ptl
+++ b/otl/gsub-cv-ss.ptl
@@ -1,4 +1,4 @@
-import [add-common-feature pick-feature add-feature-lookup pick-lookup] from "./table-util"
+import [add-common-feature pick-feature add-feature-lookup pick-lookup BeginLookupBlock EndLookupBlock] from "./table-util"
 import [AnyCv] from "../support/gr"
 
 define [FeatureName tag] : tag + '_cvss'
@@ -7,6 +7,8 @@ define [LookupName tag]  : 'lookup_cvss_' + tag
 export : define [buildCVSS sink para glyphList] : begin
 	if [not para.enableCvSs] : return nothing
 
+	local rec : BeginLookupBlock sink
+
 	# cvxx
 	foreach [glyph : items-of glyphList]
 		foreach [gr : items-of : AnyCv.query glyph] : if gr.tag : begin
@@ -27,3 +29,5 @@ export : define [buildCVSS sink para glyphList] : begin
 
 			foreach [{ch tag} : pairs-of composition.__cvmap]
 				add-feature-lookup feature [LookupName tag]
+
+	EndLookupBlock rec sink
diff --git a/otl/gsub-ligation.ptl b/otl/gsub-ligation.ptl
index eae5ffb6f9..acfff571fd 100644
--- a/otl/gsub-ligation.ptl
+++ b/otl/gsub-ligation.ptl
@@ -1,4 +1,4 @@
-import [add-common-feature add-feature ChainRuleBuilder query-related-glyphs] from "./table-util"
+import [add-common-feature add-feature ChainRuleBuilder query-related-glyphs BeginLookupBlock EndLookupBlock] from "./table-util"
 
 extern Set
 
@@ -12,8 +12,10 @@ define preserved null
 define advance : lambda [t] : t.map : lambda [x] x
 
 export : define [buildLigations sink para plm glyphs] : begin
+	local rec : BeginLookupBlock sink
 	local rankedLookups {}
 	foreach [ {featureName mappedFeature} : pairs-of plm] : buildLigationsImpl sink para glyphs featureName mappedFeature rankedLookups
+	EndLookupBlock rec sink
 
 define [buildLigationsImpl sink para glyphs featureName mappedFeature rankedLookups] : begin
 	define {chain-rule reverse-rule} : ChainRuleBuilder sink
diff --git a/otl/gsub-locl.ptl b/otl/gsub-locl.ptl
index 73ef8cd0d8..4c4560afea 100644
--- a/otl/gsub-locl.ptl
+++ b/otl/gsub-locl.ptl
@@ -1,6 +1,8 @@
-import [copy-language add-feature add-lookup] from "./table-util"
+import [copy-language add-feature add-lookup BeginLookupBlock EndLookupBlock] from "./table-util"
 
 export : define [buildLOCL sink para] : begin
+	local rec : BeginLookupBlock sink
+
 	define cyrlSRB  : copy-language sink 'cyrl_SRB ' 'cyrl_DFLT'
 	define cyrlMKD  : copy-language sink 'cyrl_MKD ' 'cyrl_DFLT'
 	define cyrlBGR  : copy-language sink 'cyrl_BGR ' 'cyrl_DFLT'
@@ -9,7 +11,7 @@ export : define [buildLOCL sink para] : begin
 	define loclSRB : add-feature sink 'locl'
 	cyrlSRB.features.unshift loclSRB.name
 	cyrlMKD.features.unshift loclSRB.name
-	loclSRB.lookups.push : add-lookup.front sink : object
+	loclSRB.lookups.push : add-lookup sink : object
 		type 'gsub_single'
 		subtables : list : if para.isItalic
 			object
@@ -24,7 +26,7 @@ export : define [buildLOCL sink para] : begin
 	# BGR
 	define loclBGR : add-feature sink 'locl'
 	cyrlBGR.features.unshift loclBGR.name
-	loclBGR.lookups.push : add-lookup.front sink : object
+	loclBGR.lookups.push : add-lookup sink : object
 		type 'gsub_single'
 		subtables : list : object
 			cyrve     'cyrve.BGR'
@@ -42,4 +44,6 @@ export : define [buildLOCL sink para] : begin
 			cyrsha    'cyrsha.italic'
 			cyrshcha  'cyrshcha.italic'
 			cyryu     'cyryu.BGR'
-			cyrtse    'cyrtse.italic'
\ No newline at end of file
+			cyrtse    'cyrtse.italic'
+
+	EndLookupBlock.Front rec sink
\ No newline at end of file
diff --git a/otl/gsub-pairing.ptl b/otl/gsub-pairing.ptl
index 6bc8272972..2ab342caeb 100644
--- a/otl/gsub-pairing.ptl
+++ b/otl/gsub-pairing.ptl
@@ -1,7 +1,9 @@
-import [add-common-feature add-feature add-lookup] from "./table-util"
+import [add-common-feature add-feature add-lookup BeginLookupBlock EndLookupBlock] from "./table-util"
 
 # Name-driven feature pairs
 export : define [buildPairFeature sink tag1 tag2 glyphs glyphList] : begin
+	local rec : BeginLookupBlock sink
+
 	local mapTag2 {.}
 	local mapTag1 {.}
 	define reHidden : regex "^\\."
@@ -23,3 +25,4 @@ export : define [buildPairFeature sink tag1 tag2 glyphs glyphList] : begin
 
 	add-common-feature sink feature1
 	add-common-feature sink feature2
+	EndLookupBlock rec sink
diff --git a/otl/gsub-thousands.ptl b/otl/gsub-thousands.ptl
index 2acc5b6a21..db8c5b739e 100644
--- a/otl/gsub-thousands.ptl
+++ b/otl/gsub-thousands.ptl
@@ -1,9 +1,11 @@
-import [add-common-feature add-feature add-lookup ChainRuleBuilder query-related-glyphs] from "./table-util"
+import [add-common-feature add-feature add-lookup ChainRuleBuilder query-related-glyphs BeginLookupBlock EndLookupBlock] from "./table-util"
 
 define-operator "~>" 880 'right' : syntax-rules
 	`(@l ~> @r) `{.left @l .right @r}
 
 export : define [buildGsubThousands sink para glyphs] : begin
+	local rec : BeginLookupBlock sink
+
 	define Thousand : add-feature sink 'THND'
 	define {chain-rule reverse-rule} : ChainRuleBuilder sink
 	define numberGlyphIDs : query-related-glyphs glyphs para {
@@ -43,4 +45,5 @@ export : define [buildGsubThousands sink para glyphs] : begin
 
 
 	Thousand.lookups.push lookupThousand1 lookupThousand2 lookupThousand3
-	add-common-feature sink Thousand
\ No newline at end of file
+	add-common-feature sink Thousand
+	EndLookupBlock rec sink
diff --git a/otl/index.ptl b/otl/index.ptl
index 82ad08a2c3..3d494ae331 100644
--- a/otl/index.ptl
+++ b/otl/index.ptl
@@ -3,7 +3,7 @@ import 'object-assign' as objectAssign
 import '../support/glyph' as Glyph
 import '../support/transform' as Transform
 
-import [CreateEmptyTable] from "./table-util"
+import [CreateEmptyTable finalizeTable MoveBackUtilityLookups] from "./table-util"
 
 import [buildLigations] from './gsub-ligation'
 import [buildCCMP] from './gsub-ccmp'
@@ -23,11 +23,14 @@ define [buildGSUB para glyphs glyphList markGlyphs] : begin
 	define gsub : CreateEmptyTable
 	set gsub.lookupDep {}
 
+	# lnum / onum
 	buildPairFeature gsub 'lnum' 'onum' glyphs glyphList
+
+	# NWID / WWID
 	if (!para.forceMonospace || para.spacing > 0) : begin
 		buildPairFeature gsub 'NWID' 'WWID' glyphs glyphList
 
-	# CCMP
+	# ccmp
 	buildCCMP gsub glyphs markGlyphs
 
 	# Ligation
@@ -37,18 +40,26 @@ define [buildGSUB para glyphs glyphList markGlyphs] : begin
 			set plm.calt para.ligation.caltBuildup
 		buildLigations gsub para plm glyphs
 
+	# cv##, ss##
 	buildCVSS gsub para glyphList
+
+	# THND
 	buildGsubThousands gsub para glyphs
 
+	# locl
+	# Builds last, but the lookups are added into the beginning of the lookup list
 	buildLOCL gsub para
 
+	MoveBackUtilityLookups gsub
 	set gsub.lookupOrder : topsort gsub.lookupDep
+	finalizeTable gsub
 	return gsub
 
 # GPOS
 define [buildGPOS para glyphs glyphList markGlyphs] : begin
 	define gpos : CreateEmptyTable
 	buildMarkMkmk gpos glyphList
+	finalizeTable gpos
 	return gpos
 
 # GDEF
diff --git a/otl/table-util.ptl b/otl/table-util.ptl
index 0d74899d88..f0051b6697 100644
--- a/otl/table-util.ptl
+++ b/otl/table-util.ptl
@@ -48,17 +48,6 @@ export : define [add-lookup sink data _prefix] : begin
 			return (prefix + n)
 		set n : n + 1
 
-set add-lookup.front : lambda [sink data _prefix] : begin
-	local prefix : _prefix || '_lut_'
-	local n 0
-	while true : begin
-		if [not sink.lookups.(prefix + n)] : begin
-			if sink.lookupDep : foreach [{key lookup} : pairs-of sink.lookups] : begin
-				sink.lookupDep.push {(prefix + n) key}
-			set sink.lookups.(prefix + n) data
-			return (prefix + n)
-		set n : n + 1
-
 export : define [pick-lookup sink name fallback] : begin
 	if sink.lookups.(name) : return sink.lookups.(name)
 	set sink.lookups.(name) fallback
@@ -77,13 +66,37 @@ export : define [add-common-feature sink fea] : begin
 
 	return fea
 
-export : define [ChainRuleBuilder sink] : begin
-	define utilityLookupPrefix '.utility-single.'
+define UtilityLookupPrefix '.utility-single.'
+
+export : define [BeginLookupBlock sink] : begin
+	return : object
+		existingLookupNames : new Set : Object.keys sink.lookups
+
+define [IsUtilityLookupId name] : [name.slice 0 UtilityLookupPrefix.length] === UtilityLookupPrefix
+
+export : define [EndLookupBlock rec sink] : begin
+	local currentLookupNames : new Set : Object.keys sink.lookups
+	foreach existing rec.existingLookupNames : foreach current currentLookupNames
+		if (![IsUtilityLookupId existing] && ![IsUtilityLookupId current] && ![rec.existingLookupNames.has current])
+			sink.lookupDep.push { existing current }
 
+set EndLookupBlock.Front : lambda [rec sink] : begin
+	local currentLookupNames : new Set : Object.keys sink.lookups
+	foreach existing rec.existingLookupNames : foreach current currentLookupNames
+		if (![IsUtilityLookupId existing] && ![IsUtilityLookupId current] && ![rec.existingLookupNames.has current])
+			sink.lookupDep.push { current existing }
+
+export : define [MoveBackUtilityLookups sink] : begin
+	local lns : new Set : Object.keys sink.lookups
+	foreach [front lns] : foreach [rear lns]
+		if (![IsUtilityLookupId front] && [IsUtilityLookupId rear])
+			sink.lookupDep.push { front rear }
+
+export : define [ChainRuleBuilder sink] : begin
 	define [createNewLookup f t] : begin
 		local subtable {.}
 		foreach [j : range 0 f.length] : set subtable.(f.(j)) t.(j)
-		return : add-lookup sink {.type 'gsub_single' .subtables {subtable}} utilityLookupPrefix
+		return : add-lookup sink {.type 'gsub_single' .subtables {subtable}} UtilityLookupPrefix
 
 	define [getSubLookup left right] : piecewise
 		[not right] null
@@ -95,7 +108,7 @@ export : define [ChainRuleBuilder sink] : begin
 			local lookupKeys : [Object.keys sink.lookups].reverse
 			foreach [name : items-of lookupKeys] : begin
 				local st sink.lookups.(name).subtables.0
-				if ([name.slice 0 utilityLookupPrefix.length] === utilityLookupPrefix) : begin
+				if [IsUtilityLookupId name] : begin
 					local compatible true
 					local matchCount 0
 					foreach [j : range 0 left.length] : begin
@@ -165,3 +178,7 @@ export : define [query-related-glyphs glyphs para entries] : begin
 		if para.enableCvSs : foreach [gr : items-of : AnyCv.query glyphs.(gid)] : begin
 			sink.push : gr.get glyphs.(gid)
 	return sink
+
+export : define [finalizeTable table] : begin
+	foreach [{key lang} : pairs-of table.languages] : begin
+		if lang.features : lang.features.sort
diff --git a/variants.toml b/variants.toml
index 661f5606f8..dad050ab2f 100644
--- a/variants.toml
+++ b/variants.toml
@@ -93,6 +93,12 @@ sampler = 'f'
 description = '`f` with bottom serif'
 f = "serifed"
 
+[simple.v-f-straight-tailed]
+tag = "VXAD"
+sampler = 'f'
+description = '`f` with straight tail'
+f = "straightTailed"
+
 [simple.v-g-singlestorey]
 tag = 'cv12'
 sampler = 'g'
@@ -148,7 +154,7 @@ description = "Tailed `i`"
 dotlessi = 'tailed'
 
 [simple.v-i-hookybottom]
-tag = "CVAA"
+tag = "VXAA"
 sampler = 'i'
 description = "`i` with a straight tail"
 dotlessi = 'hookybottom'
@@ -364,7 +370,7 @@ description = 'A more modern, beta-like Eszet'
 eszet = 'sulzbacher'
 
 [simple.v-eszet-longs-s-lig]
-tag = 'CVAC'
+tag = 'VXAC'
 sampler = 'ß'
 description = 'A more modern, beta-like Eszet'
 eszet = 'longsslig'
@@ -406,7 +412,7 @@ description = 'Reverse-slashed `0`'
 zero = 'reverse-slashed'
 
 [simple.v-zero-long-dotted]
-tag = 'CVAB'
+tag = 'VXAB'
 sampler = '0'
 description = 'Long-dotted Zero `0` like Hack'
 zero = 'longDotted'