I don't really know either why this happens...

When I draw the wireframe model, I can see some 'defects' inside the model that I believe shouldn't actually be there.

When rendered normally (no wireframe), the model shows up normally on the emulator but on the phone it will have missing triangles (holes basically).

I fixed this problem for now by using Object3D#forceGeometryIndices() which doesn't give any problem with the rendering of the model. (but the wireframe model is actually still messed up)

EDIT:

https://www.dropbox.com/s/kxyeu61vz9s8nht/bug.png?dl=0 Here's the messy model I was talking about (radius = 0.5f). It's not just these two lines, there's much more (also shorter ones)...

Whenever I check for the distances between all vertices before calling Object3D#addTriangle(), it does not show me any signs of vertices having distances to other vertices that are about the length of these defect lines. In fact the min and max lengths between vertices is: min:0.034591455 max:0.041302014

While I'd estimate that these defect lines are bigger that the radius of 0.5f... Weird..?