add Window.Color

pixelgl/window.go

@@ -397,3 +397,8 @@ func (w *Window) Smooth() bool {
 func (w *Window) Clear(c color.Color) {
 	w.canvas.Clear(c)
 }
+
+// Color returns the color of the pixel over the given position inside the Window.
+func (w *Window) Color(at pixel.Vec) pixel.NRGBA {
+	return w.canvas.Color(at)
+}