Why do we need normalized coordinate system? Options
- by jcyang
Hi,
I have problem understand following sentences in my textbook
Computer Graphics with OpenGL.
"To make viewing process independent
of the requirements of any output
device,graphic system convert object
descriptions to normalized
coordinates and apply the clipping
routines."
Why normalized coordinates could make viewing process independent
of the requirements of any output devices?
Isn't the projection coordinates already independent of output
device?We only need to first scale and then translate the projection
coordinate then we will get device coordinate.
So why do we need first
convert the projection coordinate to normalized coordinate first?
"Clipping is usually performed in
normlized coordinates.This allows us
to reduce computations by first
concatenating the various
transformation matrices"
Why clipping is usually performed in normlized coordinates? What
kind of transformation concatenated?
thanks.
jcyang.