View Full Version : Static shadows?

12-16-2002, 03:17 AM
I tried a game "Live For Speed". How are the shadows of trees in the roaddone?

12-16-2002, 04:33 AM
If you call them static shadows then most likely they're lightmaps (runs like h.ll & cheap to use). BTW I really like artwork in Hitman2 I have PII-350 (Overclocked to 434 3.5@124), 384MB RAM & GeForce2 GTS w 32VRAM & I havn't experienced any slowdowns for now. Only thing that isn't maxed out is env bumpmapings. And light+fog effects looks really great.

12-16-2002, 07:15 AM

Are lightmaps usually generated load time (is it heavy operation?) or are they ready get from file? What resolution (pixels per triangle)?

12-16-2002, 10:06 AM
Lightmaps are usually pregenerated (can be very compute intensive, radiosity and that kind of stuff) and packaged into the distribution files.

Typical resolution (wild guess) would be about 1/16th of base texture resolution (ie 1/4 in each dimension, one light map texel per 4x4 base map texels).

12-16-2002, 11:28 AM
I have used Crystal Space before, and that engine will calculate lightmaps on map load, if the lightmaps aren't cached already. They are really computation heavy, I suggest you either precalculate them or provide a mechanism for calculating and caching the 'maps, since you shouldn't expect them to change.

12-16-2002, 12:14 PM
But does this result in very many amount of lightmap textures? because every triangle in scene has its lightmap.
And thus lightmap texture coordinates cannot be per vertex, they must be per (face,corner).

This means I must render triangles separately, cannot use indexed trianglestrip (I can, but it doesn't help).

Am I right, or lacking something?