Merge branch 'fixemptycollisioncrash' into 'master'

Make empty collision shape for objects without any triangles.

Closes #7077

See merge request OpenMW/openmw!2871

CHANGELOG.md

@@ -41,6 +41,7 @@
     Bug #7044: Changing a class' services does not affect autocalculated NPCs
     Bug #7054: Quests aren't sorted by name
     Bug #7064: NPCs don't report crime if the player is casting offensive spells on them while sneaking
+    Bug #7077: OpenMW fails to load certain particle effects in .osgt format
     Bug #7084: Resurrecting an actor doesn't take into account base record changes
     Bug #7088: Deleting last save game of last character doesn't clear character name/details
     Bug #7092: BSA archives from higher priority directories don't take priority

components/resource/bulletshapemanager.cpp

@@ -74,7 +74,7 @@ namespace Resource
 
         osg::ref_ptr<BulletShape> getShape()
         {
-            if (!mTriangleMesh)
+            if (!mTriangleMesh || mTriangleMesh->getNumTriangles() == 0)
                 return osg::ref_ptr<BulletShape>();
 
             osg::ref_ptr<BulletShape> shape(new BulletShape);