title: OpenGL - add vertices
body: <p>I have a subfunction that reads a data stream and creates an array of vertex data based on that. The main function calls this subfunction repeatedly and updates the vertex data array, which is then bound to a buffer and drawn. So far, so good. However, I cannot figure out how to add vertices. C++ does not let you reassign or resize entire arrays. I can't use vectors because the OpenGL functions take in arrays, not vectors.</p>