How can I display objects in a 3D perspective projection that look like as if their size does not change, despite of the camera's position? I am using DirectX 9.0. I know of PositionTransformed declaration usage, but I was thinking of scaling the objects in every frame as the camera zooms in/out to achieve this. Is there a way to know the "scale" of a perspective projection?
An example usage would be to show lines with constant width. E.g. roads on a map.
Update, I've found the solution
check the accepted answer.