Speed up drawing and experiment with using rotation on the draw operation to get the right coordinates

internal/conv/object.go

@@ -19,6 +19,7 @@ type Sprite struct {
 	Height int
 
 	Pic *pixel.PictureData
+	Spr *pixel.Sprite
 }
 
 type Object struct {
@@ -33,10 +34,12 @@ func ConvertObject(rawObj *data.Object, name string) *Object {
 	}
 
 	for i, rawSpr := range rawObj.Sprites {
+		pic := spriteToPic(rawSpr)
 		out.Sprites[i] = Sprite{
 			Width:  int(rawSpr.Width),
 			Height: int(rawSpr.Height),
-			Pic:    spriteToPic(rawSpr),
+			Pic:    pic,
+			Spr:    pixel.NewSprite(pic, pic.Bounds()),
 		}
 	}