GLSL Area Lights (w/ texture)

I extended my realtime area light algorithm to support texture mapping. Now you can use them as if they were a texture projector, but:
-Only polygons facing the light get the projection, the projected image behaves correctly with normal mapping, specular mapping, etc.
-Colors soften with distance. This is achieved using interpolation between mipmap levels, so it is very fast.
-You get specular reflection, with the shape and colors of the area.

Texture mapped area lights are only a bit slower than a typical spotlight (they need 3 texture fetches per pixel: 1 for specular and 2 for diffuse). They ARE NOT physically correct but they LOOK correct. You could use several of them in a single scene without too much overhead.

Think of a cathedral interior with the stained glasses casting soft dynamic lighting on everything and reflecting on the floor, walls, etc. That is possible with just two area lights (each one covering all windows on each wall).

Some other effects are present in the video: HDR with tonemapping, SSAO, motion blur.
My next work is trying to get really soft shadows from these lights.

Category:

Science & Technology

Tags:

• area
• light
• glsl
• opengl
• 3D
• realtime
• texture
• map
• mapped
• colors
• stained
• glass
• lighting
• phong
• bdrf

[navyseai]

thats awesome... what is the engine name ? thats just opengl ?

[arkano22]

@navyseai

Thanks :). The engine is called Hopp, however it is pretty small so it can be considered just opengl ;).

[KRIGSSV1N]

very nice, any implementation tips?

[arkano22]

I think i´m going to write a small paper about this, including sample code. I will let you know when it is finished.

[shakemyass9878]

Framerate?

[yoyonel1808]

Very nice ! Good work !

Your approximation is interesting: 1 area-light ~= 1 spot + 1 directionnal + 1 omni.

There is a analytic solution for this case,

using the form factor between a receiver point and a polygonal light emitter (line, triangle, quad, etc ...).

I can't explain here with more details,

but i will try to do a sample for this solution.

Sorry for my english :p

YoYoOoOOoOOo

ps: very nice the (Gauss) SSAO effect (i saw yours vidz about this, very interesting !)

[KlimovArtem1]

where are the shadows? :D

[Spikecb]

@KRIGSSV1N let me know too ;) I would like to read it. Beautiful work ;)

[darkgaze]

Awesome, darling.

[Independentsoul85]

thats awesome hope devs of blender implent it