cmd

pkg/hex.go

@@ -0,0 +1,32 @@
+package imageutils
+
+import (
+	"fmt"
+	"image/color"
+	"errors"
+)
+
+var ParseHexColorErr = errors.New("invalid length, must be 7 or 4")
+
+func ParseHexColor(s string) (c color.RGBA, err error) {
+	c.A = 0xff
+	switch len(s) {
+	case 7:
+		_, err = fmt.Sscanf(s, "#%02x%02x%02x", &c.R, &c.G, &c.B)
+	case 4:
+		_, err = fmt.Sscanf(s, "#%1x%1x%1x", &c.R, &c.G, &c.B)
+		// Double the hex digits:
+		c.R *= 17
+		c.G *= 17
+		c.B *= 17
+	default:
+		err = ParseHexColorErr
+
+	}
+	return
+}
+
+func ColorToHex(c color.Color) string {
+	r, g, b, _ := color.NRGBAModel.Convert(c).RGBA()
+	return fmt.Sprintf("#%02x%02x%02x", byte(r), byte(g), byte(b))
+}