[quelsolaar]

You can do it in SO many ways! You can have one vertex buffer or double buffer it, or you can run the entire simulation on the GPU too. In general, uploading data to the GPU can be the slowest part. OpenGL, and more modern Graphics APIs have evolved in the direction of minimizing the communication between CPU and GPU since it is almost always a big bottle neck. Modern GPUs are designed to manage themselves with work queues, local data and sometimes even local storage to avoid the need to interact with the CPU.