Compute the transform from user coordinates to
Scaled coordinates in 2D:
Compute the transform from
Scaled to user coordinates:
Compute the transform from user coordinates to
Scaled coordinates in 3D:
Compute the transform from
Scaled to user coordinates:
Transform from user coordinates to
Scaled coordinates with a particular
PlotRange:
Specify the disk in user coordinates and the circle in
Scaled coordinates:
Compute the model view transform for OpenGL, using the

axis pointing out from the screen: