Fix mesh manager chicken/egg problem.

korman/exporter/convert.py

@@ -58,7 +58,7 @@ class Exporter:
             self.image = image.ImageCache(self)
             self.locman = locman.LocalizationConverter(self)
             self.decal = decal.DecalConverter(self)
-            self.oven = etlight.LightBaker(self.report)
+            self.oven = etlight.LightBaker(mesh=self.mesh, report=self.report)
 
             # Step 0.8: Init the progress mgr
             self.mesh.add_progress_presteps(self.report)

korman/exporter/etlight.py

@@ -25,10 +25,10 @@ from ..helpers import *
 
 _NUM_RENDER_LAYERS = 20
 
-class LightBaker(_MeshManager):
+class LightBaker:
     """ExportTime Lighting"""
 
-    def __init__(self, report=None, *, verbose=False):
+    def __init__(self, *, mesh=None, report=None, verbose=False):
         self._lightgroups = {}
         if report is None:
             self._report = ExportVerboseLogger() if verbose else ExportProgressLogger()
@@ -38,7 +38,11 @@ class LightBaker(_MeshManager):
         else:
             self._report = report
             self._own_report = False
-        super().__init__(self._report)
+
+        # This used to be the base class, but due to the need to access the export state
+        # which may be stored in the exporter's mesh manager, we've changed from is-a to has-a
+        # semantics. Sorry for this confusion!
+        self._mesh = _MeshManager(self._report) if mesh is None else mesh
 
         self.vcol_layer_name = "autocolor"
         self.lightmap_name = "{}_LIGHTMAPGEN.png"
@@ -52,6 +56,13 @@ class LightBaker(_MeshManager):
         if self._own_report:
             self._report.progress_end()
 
+    def __enter__(self):
+        self._mesh.__enter__()
+        return self
+
+    def __exit__(self, *exc_info):
+        self._mesh.__exit__(*exc_info)
+
     @staticmethod
     def add_progress_steps(report, add_base=False):
         if add_base:
@@ -385,8 +396,10 @@ class LightBaker(_MeshManager):
 
             # Meshes with modifiers need to have islands packed to prevent generated vertices
             # from sharing UVs. Sigh.
-            if self.is_collapsed(bo):
+            if self._mesh.is_collapsed(bo):
-                self._report.warn("'{}': packing islands in UV Texture '{}' due to modifier collapse", bo.name, uv_base.name)
+                # Danger: uv_base.name -> UnicodeDecodeError (wtf? another blender bug?)
+                self._report.warn("'{}': packing islands in UV Texture '{}' due to modifier collapse",
+                                  bo.name, modifier.uv_map, indent=2)
                 with self._set_mode("EDIT"):
                     bpy.ops.mesh.select_all(action="SELECT")
                     bpy.ops.uv.pack_islands(margin=0.01)
@@ -441,7 +454,7 @@ class LightBaker(_MeshManager):
         # future exports as an optimization. We won't reach this point if there is already an
         # autocolor layer (gulp).
         if not self.force and needs_vcol_layer:
-            self.context_stack.enter_context(TemporaryObject(vcol_layer, vcols.remove))
+            self._mesh.context_stack.enter_context(TemporaryObject(vcol_layer, vcols.remove))
 
         # Indicate we should bake
         return True

korman/exporter/mesh.py

@@ -167,6 +167,7 @@ class _MeshManager:
         self.context_stack = ExitStack()
         if report is not None:
             self._report = report
+        self._entered = False
         self._overrides = {}
 
     @staticmethod
@@ -183,6 +184,9 @@ class _MeshManager:
         return props
 
     def __enter__(self):
+        assert self._entered is False, "_MeshManager is not reentrant"
+        self._entered = True
+
         self.context_stack.__enter__()
 
         scene = bpy.context.scene
@@ -231,6 +235,7 @@ class _MeshManager:
                         if key in {"name", "type"} or (cached_mod["type"], key) in readonly_attributes:
                             continue
                         setattr(mod, key, value)
+            self._entered = False
 
     def is_collapsed(self, bo) -> bool:
         return bo.name in self._overrides