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Basiror

Lightmaps: outdated or not?

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what do you think i think it is time to finish my map compiler and i can t decide whether i should use lightmaps or not what do you think? are they outdated and should i stick with realtime lightning?

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light maps look great. your scene is static. you would be waisting your time lighting it in real time and using shadow algorithms. you can do that for all your dynamic objects.

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Yep, I agree with the others. There''s still a lot of life left in lightmaps.

If the interaction between an object and a lightsource is only ever static, then you''re wasting processing/rendering time calculating it in realtime.

For static lighting, you can use complex global illumnination solutions to create your lightmaps, something that isn''t so easily done in realtime.

Even for certain dynamic object<->light interactions that are far away from the viewer, you might not want to do the lighting for those in realtime.



--
Simon O''Connor
ex -Creative Asylum
Programmer &
Microsoft MVP

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When someone comes up with something that works for both specular and diffuse light that can be used in real time and looks better then todays apps then lightmaps will be outdated. Before that theres nothing wrong with lightmaps besides it''s only for diffuse light.

/me is about to render some lightmaps in the near future for a game.

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ok you convinced me to use lightmaps

now another question

how large should i make a lightmap
16*16 32*32 or 64*64

i know it is dependent on the polygon size

lets say how big should the lightmap be when the polygon is as big as a human player model

? and

should i store RGB values or just liminace values?

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make it 256x256!

what you can do is store 10 different variations of the light map (sharp/blurry/arcs/spots/ etc), and you will add even more distinctiveness to the surface textures, all for teh price of 1 bind somewhere in the second or third texture coordinate..

No, no, we FIXED the glitch, the problem is solved on YOUR end

www.cppnow.com

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check this out... all you need to do is write down your tex coordinates for each type (just a sample here), and you will reuse the same texture over and over with a single bind..

Imagine all th possibilities of artwork you can use as part of your actual light map shapes!



256x256, grayscale if you want.

www.cppnow.com

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actually i am talking about the classical lightmap generation approach
and quite frankly i don t know what i should think about your suggestions

256*256 sounds big especially in scenes with more than 1.000.000 polygons

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Superdeveloper didn''t mean to use a 256x256 image on *every* face.

He suggested you use a single image, like that one he posted, as a lightmap for *all* faces.

Instead of rendering images per faces, you assign them the same lightmap and adjusts the texture coordinates so they map to different (small) areas in the big lightmap.

It''s tricky, but can save loads of VRAM.

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