Loading Large Models - Unity 5 Occlusion Culling?

Hello my name is Michael,

Firstly, I must apologise if this has been answered elsewhere, I have looked around and not found an answer to this that works. I have also asked on the Vuforia Forums (Here: https://developer.vuforia.com/forum/vuforia-40/loading-large-models-unity-5-occlusion-culling) but that was a few days ago and I have not had a single reply.

Anyway, I am making a project in Unity 5 with Vuforia 4, the project requires very large models to be rendered on a tablet, that the person holding the tablet can then walk around. The models are very detailed and so, in turn, are very difficult for the tablet to load.

My first thoughts on how to fix this were to use Unity 5's Occlusion Culling technique, which works to a point. If the tablet is zoomed in on the model (in this case, a car) then everything outside of the camera is not loaded and so the tablet runs fine. However, if the tablet zooms out of the model, the tablet can't take it. Due to the size of the model, the tablet lags etc. Now, I have put into play Occlusion Culling with the hope that the outsides of the model will block the insides of the model and so prevent them from being loaded. For instance, the chassis of the car preventing the seats, steering wheel, engine etc from being loaded. Unfortunately, it seems that no matter what I do with the occlusion culling, it will not work like this. I believe it is supposed to (according to the Unity documentation and what else I have read, it is). I assumed that it is something to do with my smallest occluder in the Unity Occlusion window, alas I cannot make it smaller than 5 as the model refuses to bake if I do.

To give an example of the amount of data etc the tablet has to load with just the model car on scene its 1.7m Tris and 1.2m Verts. Nothing can be done to reduce model size, it has to be these models.

Thanks in advance for any help.

Have fun

Michael