change colors to work in uint32 and Rgba type

convertions.go

@@ -14,20 +14,28 @@ func ConvertStringUint32(s string) (uint32, error) {
 	return uint32(v), err
 }
 
-func ConvertStringToRgb(str string) ([3]uint8, error) {
-	parts := strings.SplitN(str, ",", 4)
-	if len(parts) != 3 {
-		return [3]uint8{}, fmt.Errorf("invalid rgb")
+func ConvertStringToRgba(str string) (*Rgba, error) {
+	parts := strings.SplitN(str, ",", 5)
+	if len(parts) != 4 {
+		return nil, fmt.Errorf("invalid rgba")
 	}
-	var rgb [3]uint8
+	rgba := &Rgba{}
 	for i, p := range parts {
 		n, err := strconv.ParseUint(strings.TrimSpace(p), 10, 8)
 		if err != nil {
-			return [3]uint8{}, fmt.Errorf("invalid component %d: %w", i, err)
+			return nil, fmt.Errorf("invalid component %d: %w", i, err)
 		}
-		rgb[i] = uint8(n)
+		rgba[i] = uint8(n)
 	}
-	return rgb, nil
+	return rgba, nil
+}
+
+func RgbaToUint32(r *Rgba) uint32 {
+	return uint32(r[0])<<24 | uint32(r[1])<<16 | uint32(r[2])<<8 | uint32(r[3])
+}
+
+func Uint32ToRgba(v uint32) *Rgba {
+	return &Rgba{uint8(v >> 24), uint8(v >> 16), uint8(v >> 8), uint8(v)}
 }
 
 func ConvertStringUuid(str string) (uuid.UUID, error) {