I’m having some issues with applying new textures to an instanced buffer geometry.

I create an instanced buffer geometry, copied from a PlaneBufferGeometry, currently with 6448 instances. I have different textures to be applied to the geometry so I create additional groups using addGroup.

However, the maximum number of groups I need is 1612 ( 6448 / 4), but only a single triangle of the plane geometry is being rendered. At 806 groups, the planes are rendered correctly with both triangles making up each plane being rendered.

So, I was wondering if there is some form of limit to how many groups there can be on a buffer or instanced buffer geometry? Or if not, then why would I be having the issue I am having as the number of groups increases?

Thanks.