change float64 to float32 in colorToRGBA

util.go

@@ -3,11 +3,11 @@ package pixel
 import "image/color"
 
 // colorToRGBA converts a color from image/color to RGBA components in interval [0, 1].
-func colorToRGBA(c color.Color) (r, g, b, a float64) {
+func colorToRGBA(c color.Color) (r, g, b, a float32) {
 	ri, gi, bi, ai := c.RGBA()
-	r = float64(ri) / 0xffff
-	g = float64(gi) / 0xffff
-	b = float64(bi) / 0xffff
-	a = float64(ai) / 0xffff
+	r = float32(ri) / 0xffff
+	g = float32(gi) / 0xffff
+	b = float32(bi) / 0xffff
+	a = float32(ai) / 0xffff
 	return
 }