remove unused codes

Author: mazznoer

go.mod

@@ -2,7 +2,4 @@ module github.com/mazznoer/colorgrad
 
 go 1.17
 
-require (
-	github.com/lucasb-eyer/go-colorful v1.2.0
-	github.com/mazznoer/csscolorparser v0.1.5-0.20240719031628-b1c13f071417
-)
+require github.com/mazznoer/csscolorparser v0.1.5-0.20240719031628-b1c13f071417

go.sum

@@ -1,8 +1,2 @@
-github.com/lucasb-eyer/go-colorful v1.2.0 h1:1nnpGOrhyZZuNyfu1QjKiUICQ74+3FNCN69Aj6K7nkY=
-github.com/lucasb-eyer/go-colorful v1.2.0/go.mod h1:R4dSotOR9KMtayYi1e77YzuveK+i7ruzyGqttikkLy0=
-github.com/mazznoer/csscolorparser v0.1.4 h1:1bAWPWdoMc5qdAXVlixS9rpZLw/vaq5InX/lj3tfRQQ=
-github.com/mazznoer/csscolorparser v0.1.4/go.mod h1:OQRVvgCyHDCAquR1YWfSwwaDcM0LhnSffGnlbOew/3I=
-github.com/mazznoer/csscolorparser v0.1.5-0.20240717073837-ced1c0227ecd h1:QD8NhwDjRqslqCti93tzxSjojvNUihcaYqQjGwdQAcM=
-github.com/mazznoer/csscolorparser v0.1.5-0.20240717073837-ced1c0227ecd/go.mod h1:OQRVvgCyHDCAquR1YWfSwwaDcM0LhnSffGnlbOew/3I=
 github.com/mazznoer/csscolorparser v0.1.5-0.20240719031628-b1c13f071417 h1:IdwaaP9b9TX6x7pMASy55IiksNPm73Z64ru71Nx22bw=
 github.com/mazznoer/csscolorparser v0.1.5-0.20240719031628-b1c13f071417/go.mod h1:OQRVvgCyHDCAquR1YWfSwwaDcM0LhnSffGnlbOew/3I=

util.go

@@ -4,8 +4,6 @@ import (
 	"math"
 	"strconv"
 	"strings"
-
-	"github.com/lucasb-eyer/go-colorful"
 )
 
 func linspace(min, max float64, n uint) []float64 {
@@ -126,11 +124,6 @@ func linearInterpolate(a, b [4]float64, t float64) (i, j, k, l float64) {
 	return
 }
 
-func interpAngle(a, b, t float64) float64 {
-	delta := math.Mod(((math.Mod(b-a, 360))+540), 360) - 180
-	return math.Mod((a + t*delta + 360), 360)
-}
-
 func blendRgb(a, b Color, t float64) Color {
 	return Color{
 		R: a.R + t*(b.R-a.R),
@@ -139,46 +132,3 @@ func blendRgb(a, b Color, t float64) Color {
 		A: a.A + t*(b.A-a.A),
 	}
 }
-
-func blendLrgb(a, b colorful.Color, t float64) colorful.Color {
-	r1, g1, b1 := a.LinearRgb()
-	r2, g2, b2 := b.LinearRgb()
-	return colorful.LinearRgb(
-		r1+t*(r2-r1),
-		g1+t*(g2-g1),
-		b1+t*(b2-b1),
-	)
-}
-
-func blendOklab(ca, cb colorful.Color, t float64) colorful.Color {
-	r1, g1, b1 := ca.LinearRgb()
-	r2, g2, b2 := cb.LinearRgb()
-	l1, a1, b1 := lrgbToOklab(r1, g1, b1)
-	l2, a2, b2 := lrgbToOklab(r2, g2, b2)
-	r, g, b := oklabToLrgb(
-		l1+t*(l2-l1),
-		a1+t*(a2-a1),
-		b1+t*(b2-b1),
-	)
-	return colorful.LinearRgb(r, g, b)
-}
-
-func lrgbToOklab(r, g, b float64) (L, A, B float64) {
-	l := math.Cbrt(0.4121656120*r + 0.5362752080*g + 0.0514575653*b)
-	m := math.Cbrt(0.2118591070*r + 0.6807189584*g + 0.1074065790*b)
-	s := math.Cbrt(0.0883097947*r + 0.2818474174*g + 0.6302613616*b)
-	L = 0.2104542553*l + 0.7936177850*m - 0.0040720468*s
-	A = 1.9779984951*l - 2.4285922050*m + 0.4505937099*s
-	B = 0.0259040371*l + 0.7827717662*m - 0.8086757660*s
-	return
-}
-
-func oklabToLrgb(l, a, b float64) (R, G, B float64) {
-	l_ := math.Pow(l+0.3963377774*a+0.2158037573*b, 3)
-	m_ := math.Pow(l-0.1055613458*a-0.0638541728*b, 3)
-	s_ := math.Pow(l-0.0894841775*a-1.2914855480*b, 3)
-	R = 4.0767245293*l_ - 3.3072168827*m_ + 0.2307590544*s_
-	G = -1.2681437731*l_ + 2.6093323231*m_ - 0.3411344290*s_
-	B = -0.0041119885*l_ - 0.7034763098*m_ + 1.7068625689*s_
-	return
-}