This may be more of a general programming question. I'm currently batching all of my sprites' vertices in one giant, interleaved vertex array. I don't use VBOs for this right now since I am supporting OpenGL ES 2.0, and data is likely to change frequently bit over time. Since I'm drawing everything in one draw call, I'll need to have my vertices sorted within the array in a back-to-forward fashion. All of my vertices are in stored in an STL vector. I'm trying to figure out an efficient way of doing this, though. Whenever I add a sprite to my batch, I can just insert the sprites based on depth, but what if I had to move 4 vertices making up one of my sprites back 8 vertices? Should I just insert a copy of my sprite's vertices, then erase the original copy from the vector?