Fix incorrect soft volume normal export.

The soft volumes were previously in aproximately the correct location
but the exported normals were not unit vectors. This seems to have made
the resulting soft volumes not function as intended.

korman/properties/modifiers/region.py

@@ -278,11 +278,19 @@ class PlasmaSoftVolume(idprops.IDPropMixin, PlasmaModifierProperties):
         # Initialize the plVolumeIsect. Currently, we only support convex isects. If you want parallel
         # isects from empties, be my guest...
         with TemporaryObject(bo.to_mesh(bpy.context.scene, True, "RENDER", calc_tessface=False), bpy.data.meshes.remove) as mesh:
-            mesh.transform(bo.matrix_world)
+            matrix = bo.matrix_world
+            #l2w = utils.matrix44(matrix)
+            xform = matrix.inverted()
+            xform.transpose()
 
             isect = plConvexIsect()
-            for i in mesh.vertices:
-                isect.addPlane(hsVector3(*i.normal), hsVector3(*i.co))
+            for ngon in mesh.polygons:
+                normal = xform * ngon.normal * -1
+                normal.normalize()
+                normal = hsVector3(*normal)
+                for vertex in (mesh.vertices[i] for i in ngon.vertices):
+                    pos = matrix * vertex.co
+                    isect.addPlane(normal, hsVector3(*pos))
             sv.volume = isect
 
     def _export_sv_nodes(self, exporter, bo, so):