| From: | Robert Kihl |
| Date: | 11 Aug 2001 at 04:12:54 |
| Subject: | Re: [3DWorld] Displaying FullScreen pictures. |
On 07-Aug-01, you wrote:
> I thought that it's because when drawing transparent faces GFX chip
> have to cut a one pixel from the right to eliminate everleaping faces
> (its it done this way?) so this is from the grid comes. But When
> a tile is even 0% transparent (blending disabled) this grid apears.
No I don't think it's done that way. Since 3D hardware renders with subpixel
accuracy there is no overlaping.
Consider two triangles that share one edge. If the x value of that edge at
one scanline is for example 10.3 the triangle to the left will render 'till
x = 10 and the triangle to the right will start rendering at x = 11.
So only pixels that are "inside" the triangle gets drawn, since a pixel only
can be at one side of an edge it will only get drawn for one of the
triangles that share the edge.
Hmm I hope that makes some sense :) if not, have a look at this article.
http://freespace.virgin.net/hugo.elias/graphics/x_polysc.htm
Cya