Remove manual stack walking for bottom layers.

korman/exporter/material.py

@@ -1192,9 +1192,7 @@ class MaterialConverter:
         except IndexError:
             return None
         else:
-            while layer.underLay is not None:
-                layer = layer.underLay.object
-            return layer
+            return layer.bottomOfStack.object
 
     def get_bump_layer(self, bo):
         return self._bump_mats.get(bo, None)

korman/exporter/mesh.py

@@ -41,18 +41,12 @@ class _GeoSpan:
         """Determines the color all vertex colors should be multipled by in this span."""
         if self.geospan.props & plGeometrySpan.kDiffuseFoldedIn:
             color = bm.diffuse_color
-            base_layer = self._find_bottom_of_stack()
+            base_layer = self.geospan.material.object.layers[0].object.bottomOfStack.object
             return (color.r, color.b, color.g, base_layer.opacity)
         if not bo.plasma_modifiers.lighting.preshade:
             return (0.0, 0.0, 0.0, 0.0)
         return (1.0, 1.0, 1.0, 1.0)
 
-    def _find_bottom_of_stack(self) -> plLayerInterface:
-        base_layer = self.geospan.material.object.layers[0].object
-        while base_layer.underLay is not None:
-            base_layer = base_layer.underLay.object
-        return base_layer
-
 
 class _RenderLevel:
     MAJOR_OPAQUE = 0