I’m trying to use OpenGL in rust using the gl crate and rust bindings to glfw. I’ve had some success with OpenGL in C, but for this project, I am just trying to port the “hello triangle” code from LearnOpenGL.com. Link To Source . Using the original vertices provided I noticed the triangle was not where it was supposed to be. At first I thought it was the viewport, but eventually I messed with the vertices themselves and the results are not what I would have expected. So I inserted calls to gl::GetBufferSubData to see if I would get back what I expect, and I don’t at all. I think there must be a basic memory/pointer error going on, or a bad typecast or something like that, but I really can’t figure it out. It’s also possible that my calls to gl::GetSubBufferData are wrong somehow too, but I would think they would be wrong in a similar way.