Make sure strips have valid size

components/nifbullet/bulletnifloader.cpp

@@ -63,7 +63,7 @@ void fillTriangleMeshWithTransform(btTriangleMesh& mesh, const Nif::NiTriStripsD
 
     // Assume every strip has the same size
     const int singleStripSize = static_cast<int>(strips[0].size());
-    // Can't make a triangle from 2 vertices or less.
+    // Can't make a triangle from less than three vertices.
     if (singleStripSize < 3)
         return;
 

components/nifosg/nifloader.cpp

@@ -1128,6 +1128,10 @@ namespace NifOsg
             {
                 for (const std::vector<unsigned short>& strip : data->strips)
                 {
+                    // Can't make a triangle from less than three vertices.
+                    // All strips have the same size.
+                    if (strip.size() < 3)
+                        break;
                     geometry->addPrimitiveSet(new osg::DrawElementsUShort(osg::PrimitiveSet::TRIANGLE_STRIP, 
                                                                             strip.size(), (unsigned short*)strip.data()));
                 }