Q:

Fastest way of doing transformations (Move, Rotate, Scale)

I was looking at this vector drawing application called Creative Docs .Net . I noticed that I can have hundreds of shapes and moving, rotating and scaling do not lag at all. Given that all verticies must be modified, how do applications generally do these transformations as quickly as possible?
Thanks

A:

One typical way to do it is to apply a 3x3 (or 3x2, or 2x3) affine transformation matrix to the coordinates, which can describe things like position, rotation, scale and shear.
If you use OpenGL or Direct3D you can use the graphics hardware to do the actual transformations for you.
If you do it in software, rasteration is probably going to be the bottleneck, not transforming the vertices.

