Color blending

4 files changed, 39 insertions, 0 deletions

diff --git a/drw/drw.go b/drw/drw.go
index a0b3579..e5a16c2 100644
--- a/drw/drw.go
+++ b/drw/drw.go
@@ -7,6 +7,7 @@ import (
 	"hhvn.uk/hbspbar/config"
 
 	"github.com/jezek/xgbutil/xgraphics"
+	col "github.com/lucasb-eyer/go-colorful"
 	"github.com/BurntSushi/freetype-go/freetype"
 )
 
@@ -52,3 +53,20 @@ func AddImg(dst *image.RGBA, x, w int, src *image.RGBA) {
 	r := image.Rect(x, 0, x + w, int(config.H))
 	draw.Draw(dst, r, src, image.Pt(0,0), draw.Src)
 }
+
+func Blend3(a, b, c uint32, percent int) uint32 {
+	if percent <= 50 {
+		return Blend(a, b, percent * 2)
+	} else {
+		return Blend(b, c, (percent - 50) * 2)
+	}
+}
+
+// Conversion hell, I know
+func Blend(a, b uint32, percent int) uint32 {
+	ac, _ := col.MakeColor(int2rgb(a))
+	bc, _ := col.MakeColor(int2rgb(b))
+
+
+	return rgb2int(ac.BlendHcl(bc, float64(percent) / 100).Clamped())
+}
diff --git a/drw/x.go b/drw/x.go
index 1806410..c004d78 100644
--- a/drw/x.go
+++ b/drw/x.go
@@ -77,6 +77,24 @@ func int2rgb(argb uint32) (color.RGBA) {
 		A: uint8((argb & 0xff000000) >> 24) }
 }
 
+func rgb2int(c color.Color) uint32 {
+	r, g, b, a := c.RGBA()
+
+	r /= 256
+	g /= 256
+	b /= 256
+	a /= 256
+
+	var ret uint32 = 0
+
+	ret |= (a << 24)
+	ret |= (r << 16)
+	ret |= (g << 8)
+	ret |=  b
+
+	return ret
+}
+
 type Window struct {
 	id xproto.Window
 }
diff --git a/go.mod b/go.mod
index 283b859..b969cff 100644
--- a/go.mod
+++ b/go.mod
@@ -7,4 +7,5 @@ require (
 	github.com/BurntSushi/graphics-go v0.0.0-20160129215708-b43f31a4a966 // indirect
 	github.com/jezek/xgb v1.1.0 // indirect
 	github.com/jezek/xgbutil v0.0.0-20230603163917-04188eb39cf0 // indirect
+	github.com/lucasb-eyer/go-colorful v1.2.0 // indirect
 )
diff --git a/go.sum b/go.sum
index 9e49f1c..07541f2 100644
--- a/go.sum
+++ b/go.sum
@@ -6,3 +6,5 @@ github.com/jezek/xgb v1.1.0 h1:wnpxJzP1+rkbGclEkmwpVFQWpuE2PUGNUzP8SbfFobk=
 github.com/jezek/xgb v1.1.0/go.mod h1:nrhwO0FX/enq75I7Y7G8iN1ubpSGZEiA3v9e9GyRFlk=
 github.com/jezek/xgbutil v0.0.0-20230603163917-04188eb39cf0 h1:Pf/0BAbppEOq4azPH6fnvUX2dycAwZdGkdxFn25j44c=
 github.com/jezek/xgbutil v0.0.0-20230603163917-04188eb39cf0/go.mod h1:AHecLyFNy6AN9f/+0AH/h1MI7X1+JL5bmCz4XlVZk7Y=
+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=