Archived

This topic is now archived and is closed to further replies.

fatherjohn666

octrees and lighting

Recommended Posts

fatherjohn666    122
I am looking at octrees and stuff. IF I draw 500 lights in an opengl scene and use an octree to provide me with surface culling does this mean that since the lights wont be drawn for some parts, that openGL wont count them against the max 8 lights on screen tally? does this make sense? on a large map done in 3d max, I could then draw 40 lights and activate the lot couldn''t I? as long as the culling restricts my lights to 8 or less DRAWN on screen at one time, I should be ok yeah? How has this been done to restrict lighting in a game when lighting plays such an important part in some scenes (if on a level I could count 90 lights, is the culling the only thing stopping open gl from crashing out due to too many lights????) Im just a beginner!!! http://www.actsofgord.com

Share this post


Link to post
Share on other sites
Ingenu    1629
8 lights isn''t the maximum, you must ask the driver to know what it is, however it''s the common light coount (or minimum, don''t remember).

Anyway most 3D accelerators have a hard time using many lights, where many is > 1 ^^

So yes, you must only activate a numbre of lights < max number at any time during the drawing, however you''d better not use more than 2 or 3.

GF2 and 3 I beleive take something like 25% hit when using 2 lights, and 33% or more using 3.


-* So many things to do, so little time to spend. *-

Share this post


Link to post
Share on other sites
zedzeek    528
see the new screenshot in the kea link below.
50 lights onscreen. (not gl lights but dot3 textures)
but the principle is the same each vertice in the scene prolly only receives lighting from 3-4 lights.
ie the 8 lights restriction (some hardware can do 24 btw) is per vertex thus u dont wanna enable a light + draw an object when its over on the other side of the screen cause A performance will suck B/ visually it will make bugger all difference


http://uk.geocities.com/sloppyturds/kea/kea.html
http://uk.geocities.com/sloppyturds/gotterdammerung.html

Share this post


Link to post
Share on other sites