Optimize convex hull export.

Avoiding the context switches appears to be a huge boon for performance.
With 100 iterations on an arbitrary mesh, the improvement was 17s to
2.55s.

korman/exporter/physics.py

@@ -13,13 +13,15 @@
 #    You should have received a copy of the GNU General Public License
 #    along with Korman.  If not, see <http://www.gnu.org/licenses/>.
 
+import bmesh
 import bpy
+import itertools
 import mathutils
 from PyHSPlasma import *
 import weakref
 
 from .explosions import ExportError, ExportAssertionError
-from ..helpers import TemporaryObject
+from ..helpers import bmesh_from_object, TemporaryObject
 from . import utils
 
 def _set_phys_prop(prop, sim, phys, value=True):
@@ -58,18 +60,11 @@ class PhysicsConverter:
                 indices += (v[0], v[2], v[3],)
         return indices
 
-    def _convert_mesh_data(self, bo, physical, local_space, indices=True, mesh_func=None):
-        try:
-            mesh = bo.to_mesh(bpy.context.scene, True, "RENDER", calc_tessface=False)
-        except:
-            raise ExportError("Unable to convert object [{}] '{}' to a mesh. Make sure you didn't try to use this object as a region!",
-                              bo.type, bo.name)
+    def _convert_mesh_data(self, bo, physical, local_space, indices=True):
         mat = bo.matrix_world
 
+        mesh = bo.to_mesh(bpy.context.scene, True, "RENDER", calc_tessface=False)
         with TemporaryObject(mesh, bpy.data.meshes.remove):
-            if mesh_func is not None:
-                mesh_func(mesh)
-
             if local_space:
                 mesh.update(calc_tessface=indices)
                 physical.pos = hsVector3(*mat.to_translation())
@@ -264,21 +259,19 @@ class PhysicsConverter:
         # Only certain builds of libHSPlasma are able to take artist generated triangle soups and
         # bake them to convex hulls. Specifically, Windows 32-bit w/PhysX 2.6. Everything else just
         # needs to have us provide some friendlier data...
-        def _bake_hull(mesh):
-            # The bmesh API for doing this is trash, so we will link this temporary mesh to an
-            # even more temporary object so we can use the traditional operator.
-            # Unless you want to write some code to do this by hand...??? (not me)
-            bo = bpy.data.objects.new("BMeshSucks", mesh)
-            bpy.context.scene.objects.link(bo)
-            with TemporaryObject(bo, bpy.data.objects.remove):
-                bpy.context.scene.objects.active = bo
-                bpy.ops.object.mode_set(mode="EDIT")
-                bpy.ops.mesh.select_all(action="SELECT")
-                bpy.ops.mesh.convex_hull(use_existing_faces=False)
-                bpy.ops.object.mode_set(mode="OBJECT")
-
-        physical.verts = self._convert_mesh_data(bo, physical, local_space, indices=False,
-                                                 mesh_func=_bake_hull)
+        with bmesh_from_object(bo) as mesh:
+            mat = bo.matrix_world
+            if local_space:
+                physical.pos = hsVector3(*mat.to_translation())
+                physical.rot = utils.quaternion(mat.to_quaternion())
+                bmesh.ops.scale(mesh, vec=mat.to_scale(), verts=mesh.verts)
+            else:
+                mesh.transform(mat)
+
+            result = bmesh.ops.convex_hull(mesh, input=mesh.verts, use_existing_faces=False)
+            BMVert = bmesh.types.BMVert
+            verts = itertools.takewhile(lambda x: isinstance(x, BMVert), result["geom"])
+            physical.verts = [hsVector3(*i.co) for i in verts]
 
     def _export_sphere(self, bo, physical, local_space):
         """Exports sphere bounds based on the object"""

korman/helpers.py

@@ -13,9 +13,22 @@
 #    You should have received a copy of the GNU General Public License
 #    along with Korman.  If not, see <http://www.gnu.org/licenses/>.
 
+import bmesh
 import bpy
+from contextlib import contextmanager
 import math
 
+@contextmanager
+def bmesh_from_object(bl):
+    """Converts a Blender Object to a BMesh with modifiers applied."""
+    mesh = bmesh.new()
+    try:
+        # Empirical evidence indicates that this applies Blender Modifiers
+        mesh.from_object(bl, bpy.context.scene)
+        yield mesh
+    finally:
+        mesh.free()
+
 class GoodNeighbor:
     """Leave Things the Way You Found Them! (TM)"""