lightmap calculation speed

that''s something you have to live with. and a minute for lighting a whole level really isn''t much. You can make it faster with optimizing, and using an octree or bsp structure for your world, so you don''t have to test a ray against every face. but it will always take some time. and if you add radiosity to it, it will surely take more than a few hours to light a level.

btw. go to gollum.flipcode.com. he made a renderfarm just to compute lightmaps. so radiosity is slow enough to build a render farm for it.

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Cache your raytraces. Ex.: chances are, if a lumel is shadowed by a triangle X, its neighboor will also be. Test X in priority, then do your standard algorithm.

Y.

i think i know why mines is slow, i did:

for allights
  for allfaces
  next
next
 

should be

for allfaces
  for alllights
  next
next
 

(i dont use VB, i use vc++, but i still like basic:D)

what''s the difference, except for maybe some more efficient cach use?

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use a form of bsp, or you''ll die before your trace is done on large objects
esp if you do radiosity
With a octree, you can expect 100000 rays/s on a 100000 triangle mesh.

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think that theres 100000 triangles, 100lights

for allights
  for allfaces
    if(bLightCanTravelToFace)
      calclights()
  next
next
  

you''ll have to loop the 100000 triangles 100 times

should be

for allfaces
  for alllights
    if(bLightCanTravelToFace)
      calclights()
  next
next
  

you''ll have to loop the 100000 triangles 1 time

Yeah, but if you''ve got one hundred lights, you still execute the inner code 100*10000 times. You might have acceleration structures which work better that way round, but the code you posted has equivalent time complexity