Fastest way to find world -> screen mapping

[Robert Skinner]

In article <1991Jun4.032014.18721 at resmel.bhp.com.au>, tim at merlin.resmel.bhp.com.au (Tim Monks,,) writes:
|> To unask the question: I want to draw an object of fixed
|> screen dimensions at (x,y,z) in world coodinates. I can't
|> see how to use matrix ops. to do this.
|> --
|> Dr Tim Monks                                
|> Image Processing & Data Analysis Group | (direct)   (+61-3)566-7448
|> BHP Research - Melbourne Laboratories  | (switch)   (+61-3)560-7066
|> 245 Wellington Rd, Mulgrave, 3170,     | (fax)      (+61-3)561-6709
|> AUSTRALIA                              | (internet) tim at resmel.bhp.com.au


why can't you simply replace the viewing matrix with one appropriate
to draw your screenspace object, then just draw it?  

Its not really clear if you have any other requirements you haven't
stated, but this seems to be the easy way to draw something in screen
space.  

-- 
Robert Skinner
robert at sgi.com

	"... friends get free access to private members."

				- Ira Pohl