(graphics) Calculate offset in a moder controlable way

Author: ahyangyi

agrf/graphics/sprites/map.py

@@ -11,11 +11,13 @@ def __init__(self, a, f, name, xofs=0, yofs=0):
         if not isinstance(a, tuple):
             a = (a,)
         super().__init__(
-            a[0].w, a[0].h, zoom=a[0].zoom, xofs=a[0].xofs + xofs, yofs=a[0].yofs + yofs, bpp=a[0].bpp, crop=a[0].crop
+            a[0].w, a[0].h, zoom=a[0].zoom, xofs=a[0].xofs, yofs=a[0].yofs, bpp=a[0].bpp, crop=a[0].crop
         )
         self.a = a
         self.f = f
         self._fname = name
+        self._relative_xofs = xofs
+        self._relative_yofs = yofs
 
     def get_fingerprint(self):
         return {"a": [x.get_fingerprint() for x in self.a], "name": self._fname}
@@ -28,4 +30,7 @@ def get_data_layers(self, context):
         fa = self.f([LayeredImage.from_sprite(x).copy() for x in self.a])
         timer.count_composing()
 
+        self.xofs = fa.xofs + self._relative_xofs
+        self.yofs = fa.yofs + self._relative_yofs
+
         return fa.w, fa.h, fa.rgb, fa.alpha, fa.mask