Opengl vbo recommendations

Question

I have a model developed in Blender that I am going to make in my game engine built using opengl after exporting to collada. The model in the blender is divided into groups. These groups contain versal normals and textures with their own index. is it a good thing if I present each group as a separate vbo or should it display the whole model as a single vbo?

Answer 1

Thumb rules:

• always makes as few openGL state changes as possible;
• always talk with OpenGL as little as possible.

The main reason is that talking to the GPU is expensive. The GPU is much happier if you give it something that takes a long time, and then don’t worry while it is running. Thus, it is likely that one VBO will be the best solution, unless it leads to a significant increase in the amount of storage that you need to use, and therefore work against caching elsewhere.