[openbeos] Re: The Scientific Method aka Bresenham NewsletterArticle
- From: "Alexander G. M. Smith" <agmsmith@xxxxxxxxxx>
- To: openbeos@xxxxxxxxxxxxx
- Date: Mon, 09 Jun 2003 20:39:48 -0400 EDT
Michael Phipps wrote on Mon, 09 Jun 2003 19:01:31 -0400:
> I didn't consider this. Given the 80 bit nature of the FPU and the (fairly)
> small numbers that we are using, it wouldn't seem like it could ever be a
> more than 1 pixel error. I did see differences between the two algorithms,
> but I really had/have no real way to prove error.
That sort of rounding problem shows up as gaps between polygons in 3D systems,
since the edges are usually placed using a line drawing algorithm. You want
the line to be exactly the same, no matter what the order of the endpoints is.
It's a bit trickier since the vertices are floating point numbers until the
very last transformation step. Takes a lot of care to get it "pixel perfect".
- Alex
Other related posts:
