I finally figured out how to deal with hooks.

buildglyphs.patel

@@ -21,6 +21,7 @@ define [bilinear x0 x1 y0 y1 z00 z01 z10 z11 x y] : linreg
 	* y1
 	linreg x0 z01 x1 z11 x
 	* y
+define [clamp l h x] : if (x < l) l : if (x > h) h x
 
 define [fallback] : for [local j 0] (j < arguments.length) [inc j] : if (arguments.(j) !== nothing) : return arguments.(j)
 
@@ -167,7 +168,7 @@ define [buildFont para recursive] : begin
 	define OPERATORSTROKE : adviceBlackness 3.2
 	define SHOULDERFINE : [adviceBlackness 4] / 2
 	
-	define [adviceSSmooth y sign] : y * 0.20 + STROKE * 0.25 + 0.0583 * (RIGHTSB - SB) + sign * globalTransform.yx * para.smoothadjust
+	define [adviceSSmooth y sign] : y * 0.22 + STROKE * 0.22 + 0.0583 * (RIGHTSB - SB) + sign * globalTransform.yx * para.smoothadjust
 	define [adviceGlottalStopSmooth y sign] : ((y - STROKE) * 0.25 + STROKE / 2) + sign * globalTransform.yx * para.smoothadjust
 	define [shoulderMidSlope _fine _stroke _dir] : 0.5 * CORRECTION_HX * ([fallback _stroke STROKE] - [fallback _fine SHOULDERFINE]) / [fallback _stroke STROKE] + [fallback _dir 1] * globalTransform.yx
 	

glyphs/autobuilds.patel

@@ -122,7 +122,7 @@ define [subParts parts] : begin
 	foreach p [items-of parts] : if [isAboveMark p] : set hasMarkAbove true
 	
 	# replace dotted-i and dotted-j with dotless equalivents
-	if ((parts.0 === glyphs.i || parts.0 === glyphs.cyrUkraniani) && hasMarkAbove) : parts.0 = glyphs.dotlessi
+	if ((parts.0 === glyphs.i || parts.0 === glyphs.cyrUkrainiani) && hasMarkAbove) : parts.0 = glyphs.dotlessi
 	if (parts.0 === glyphs.j && hasMarkAbove) : parts.0 = glyphs.dotlessj
 	
 	# replace below marks with trailing marks

glyphs/common-shapes.patel

@@ -290,50 +290,59 @@ define [FlipAround x y sx sy] : glyph-construction
 	apply-transform : Italify
 
 # Spiro shapes
-define [sband sw rtl _tension _tangle _compression] : return {.type 'interpolate' .af [lambda [before after] : begin \\
+define [determineMixR w v] : piecewise
-	local tension : fallback _tension 0.7
+	(w <= v) 0.5
-	local compression : fallback _compression 1
+	true     ((w * w - [Math.sqrt : (2 * w - v) * v * w * w]) / ((v - w) * (v - w)))
-	local tensionw 0
+define [calculateHook u w v p] : begin
-	local minangle : -para.italicangle / 180 * Math.PI
+	if (w <= v) : return {0.5, 0}
-	local maxangle : Math.atan2 (after.x - before.x) ([mix after.y before.y tension] - [mix before.y after.y tension])
+	local mixr : determineMixR w v
-	set maxangle : Math.atan2 ([Math.sin maxangle] * compression) [Math.cos maxangle]
+	local mixrRho : clamp 0.97 1 (1 + (1 - w / (u * mixr)) / 15)
-	local p : fallback _tangle 0.25
+	local k : w * (mixr - 1) / (mixr * [Math.sqrt : 2 * mixr - 1] * u)
-	local pts {}
+	local deltay : STROKE / [Math.sqrt : 1 + k * k]
-	local samples 32
+	local deltax : k * deltay
-	foreach j [range 1 samples] : begin
+	local winner (w - STROKE)
-		local t : j / samples
+	local vinner (v - STROKE + deltay)
-		local angle : mix minangle maxangle [bez3 0 p 1 1 : if (t < 1/2) (2 * t) (2 * (1 - t))]
+	if (winner <= 0 || vinner <= 0 || winner <= vinner) : return {[fallback p (mixrRho * mixr)], 0}
-		local k : bez3 0 tensionw (1 - tensionw) 1 t
+	local mixrinner : determineMixR winner vinner
-		if rtl : k = 1 - k
+	local skew : 1 / STROKE * (u * mixr - ((u - STROKE * CORRECTION_HX + deltax) * mixrinner + STROKE * CORRECTION_HX)) + globalTransform.yx
-		pts.push : g2 [mix before.x after.x [bez3 0 0 1 1 t]] [mix before.y after.y [bez3 0 tension (1 - tension) 1 t]] [widths.heading ((1 - k) * STROKE) (k * STROKE) {.x [Math.cos angle] .y [Math.sin angle]}]
+	return {[fallback p (mixrRho * mixr)], skew}
-	# throw 'w'
+
-	return pts
+define [hookstart y p] : return {.type 'interpolate' .af [lambda [before after] : begin \\
-]}
-define [determineMixR w v] : if (w == v) 0.5 ((w * w - [Math.sqrt : (2 * w - v) * v * w * w]) / ((v - w) * (v - w)))
-define [hookstart y p f] : return {.type 'interpolate' .af [lambda [before after] : begin \\
 	local atBottom : after.y > y
 	local ltr : after.x > before.x
 	before.x = before.x - OXHOOK * [if ltr (-1) 1]
-	local hv : archv
+	
-	local mixr : determineMixR (after.y - y) (before.y - y)
+	local w : Math.abs (after.y - y)
+	local v : Math.abs (before.y - y)
+	local u : Math.abs (after.x - before.x)
+	local {mixr, skew} : calculateHook u w v p
 	local mx ([mix after.x before.x mixr] + [if atBottom 1 (-1)] * CORRECTION_OMIDS)
+	local hv : archv
 	return : list
-		g4.[if ltr "right" "left"].mid mx y f
+		g4.[if ltr "right" "left"].mid mx y [heading {
+			.y [if ltr 1 (-1)] 
+			.x (skew * [if atBottom (-1) (1)]) }]
 		hv.af.call this {.x mx .y y} after hv
 ]}
-define [hookend y p f dontextend] : return {.type 'interpolate' .af [lambda [before after] : begin \\
+define [hookend y p] : return {.type 'interpolate' .af [lambda [before after] : begin \\
 	local atBottom : before.y > y
 	local ltr : after.x > before.x
 	after.x = after.x + OXHOOK * [if ltr (-1) 1]
-	local vh : arcvh
+
-	local mixr : determineMixR (before.y - y) (after.y - y)
+	local w : Math.abs (before.y - y)
+	local v : Math.abs (after.y - y)
+	local u : Math.abs (after.x - before.x)
+	local {mixr, skew} : calculateHook u w v p
 	local mx ([mix before.x after.x mixr] + [if atBottom 1 (-1)] * CORRECTION_OMIDS)
-	if (!dontextend && atBottom && ltr) : begin
+	if (atBottom && ltr) : begin
 		after.x = after.x + TAILADJX * globalTransform.yx
 		after.y = after.y - TAILADJY * globalTransform.yx
+	local vh : arcvh
 	return : list
 		vh.af.call this before {.x mx .y y} vh
-		g4.[if ltr "right" "left"].mid mx y f
+		g4.[if ltr "right" "left"].mid mx y [heading {
+			.y [if ltr 1 (-1)] 
+			.x (skew * [if atBottom 1 (-1)]) }]
 ]}
 
 # Derived subfonts

glyphs/latin-basic-lower.patel

@@ -136,7 +136,7 @@ define [SmallEShape top stroke barpos curly] : glyph-construction
 		flat.ai (SB + O) (top - SMALLSMOOTHA)
 		curl.ai (SB + O) (0 + SMALLSMOOTHB)
 		hookend O
-		g4 (RIGHTSB - O) HOOK
+		g4 (RIGHTSB - O) AHOOK
 	include : HBarBottom (SB + (stroke / 2)) (RIGHTSB - (stroke / 2)) barbottom stroke
 
 create-glyph 'e' : glyph-construction

glyphs/latin-extend-basis.patel

@@ -729,7 +729,7 @@ define [RevSmallEShape top stroke barpos] : glyph-construction
 		flat (RIGHTSB - O) (top - SMALLSMOOTHB)
 		curl (RIGHTSB - O) SMALLSMOOTHA
 		hookend O
-		g4 (SB + O) HOOK
+		g4 (SB + O) AHOOK
 	include : HBarBottom (SB + (stroke / 2)) (RIGHTSB - (stroke / 2)) barbottom stroke
 
 create-glyph 'reve' : glyph-construction

parameters.toml

@@ -1,7 +1,7 @@
 [iosevka]
 family = 'Iosevka'
-version = '1.0-beta4'
+version = '1.0-beta5'
-codename = 'Yamanashi'
+codename = 'Nekojishi'
 copyright = 'Copyright (c) 2015 Belleve Invis.'
 licence = '''This font software is licenced under the SIL Open Font Licence, Version 1.1. This is licence is avaliable with a FAQ at: http://scripts.sil.org/OFL. This font software is distributes on an 'AS IS' basis, without warranties or conditions of any kind, either express or implied. See the SIL Open Font licence fot the specific language, premissions and limitations governing your use of this font software.'''
 
@@ -28,9 +28,9 @@ fivebarpos = 0.55
 
 lllcrowdedness = 3.33333333
 
-hook = 145
+hook = 155
 ahook = 130
-shook = 90
+shook = 130
 jhook = 135
 fhook = 120
 rhook = 100