I have an OpenGL scene in which the user can rotate the camera. I have some two dimensional shapes that I would like to always face the user. I do have the forward facing vector, and I do have the screen point at which the component should be drawn. I’m not sure the best way to approach this problem – should I be rotating the shape to the forward vector (which I’m not entirely sure how to do correctly)? Or is there another way I can just draw in two dimensions and ignore the rotation of the camera (maybe by using an orthographic projection)? Any sample code for helping with this would be appreciated.
PS – I’m doing this in Java, but the language is irrelevant here (it is just OpenGL specific).
I already answered it in Inverting rotation in 3D, to make an object always face the camera?