X backend properly converts image data

x/window.go

@@ -184,8 +184,12 @@ func (this *window) SetIcon (sizes ...canvas.Texture) {
 
 	for _, icon := range sizes {
 		// TODO we use textures now. make this better
-		width  := icon.Bounds().Max.X
-		height := icon.Bounds().Max.Y
+		icon, ok := icon.(*xcanvas.Texture)
+		if !ok { continue }
+		
+		bounds := icon.Bounds()
+		width  := bounds.Dx()
+		height := bounds.Dy()
 		wmIcon := ewmh.WmIcon {
 			Width:  uint(width),
 			Height: uint(height),
@@ -195,18 +199,14 @@ func (this *window) SetIcon (sizes ...canvas.Texture) {
 		// manually convert image data beacuse of course we have to do
 		// this
 		index := 0
-		for y := 0; y < height; y ++ {
-		for x := 0; x < width;  x ++ {
-			r, g, b, a := icon.At(x, y).RGBA()
-			r >>= 8
-			g >>= 8
-			b >>= 8
-			a >>= 8
+		for y := bounds.Min.Y; y < bounds.Max.Y; y ++ {
+		for x := bounds.Min.X; x < bounds.Max.X; x ++ {
+			pixel := icon.BGRAAt(x, y)
 			wmIcon.Data[index] =
-				(uint(a) << 24) |
-				(uint(r) << 16) |
-				(uint(g) << 8)  |
-				(uint(b) << 0)
+				(uint(pixel.A) << 24) |
+				(uint(pixel.R) << 16) |
+				(uint(pixel.G) << 8)  |
+				(uint(pixel.B) << 0)
 			index ++
 		}}