Reducing number of divisions for polygon mappers – part 2 March 24, 2008
Posted by winden in coding, demoscene.trackback
NOTE: moving to my new winden homepage
The software rendering world
trackback
-
winden google shared items- An error has occurred; the feed is probably down. Try again later.
1 my other pages
2 my scene productions
- 01 – Distortions
- 02 – Supportro
- 03 – Metroparty
- 04 – Birthday
- 05 – No More Lies
- 06 – Trashcan 3 Spanish
- 07 – Trashcan 3 English
- 08 – Euskal Party 5 Invitation Demo
- 09 – Trashcan 4 Spanish
- 10 – Trashcan 4 English
- 11 – Synthesis
- 12 – Daripper-demo
- 13 – Trashcan 5 English
- 14 – Crossing the Deadline
- 15 – Follow Me
- 16 – Ravanatro
- 17 – Deadpixel Controversy
- 18 – newschool amiga demos presentation slides
3 colegas
4 scene sites
Categories
Archives
- May 2009 (1)
- November 2008 (2)
- October 2008 (2)
- September 2008 (2)
- August 2008 (2)
- July 2008 (1)
- June 2008 (2)
- May 2008 (3)
- April 2008 (1)
- March 2008 (5)
- January 2008 (6)
- December 2007 (4)
- November 2007 (2)
- October 2007 (1)
- September 2007 (3)
- August 2007 (10)
- July 2007 (6)
- June 2007 (2)
- May 2007 (1)
- April 2007 (6)
- March 2007 (5)
- February 2007 (1)
- December 2006 (3)
- November 2006 (4)
- October 2006 (3)
- September 2006 (5)
- August 2006 (1)
- July 2006 (4)
- May 2006 (5)
- April 2006 (1)
- February 2006 (3)
- January 2006 (2)
- November 2005 (2)
- October 2005 (1)
- September 2005 (2)
- August 2005 (3)
- July 2005 (1)
- April 2005 (2)
- March 2005 (1)
- February 2005 (2)
- December 2004 (1)
- November 2004 (2)
- October 2004 (1)
- September 2004 (1)
- August 2004 (5)
So this mean you can back-face-cull _before_ projection… Nice. Ah, 1/(zzz*zzz) is always positive so it will not change the sign of “area” (so only need to do the division when the back face test actually passes)
Yes, not doing any divide if it is back-facing is nice :)
Interesting, though using the original 3d coordinates for back face culling instead of the projected ones produces little problems like polygons disappearing before their time, but those problems are mostly happening if you try to render a glenz cube and have different color for back and front, not for solid objects.