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Bulk particles

I play with the idea of ​​bulk particles. By “volumetric” I do not mean actually a three-dimensional model on a particle - it is usually more expensive and more difficult to mix with other particles. I mean 2D particles that will look as close to the volume as possible. We are currently trying to use particles with an additional local Z texture (for example, spherical), and we conduct alpha transparency according to the combination of alpha value and proximity on Z, which improves due to the fact that the particles do not have one flat Z I think that a cool addition will interact with lighting (and shadows), but here the question arises as to what the lighting formula looks like (taking into account transparency, suppose we are talking about smoke and dust / clouds and not adding a blend) - any suggestions will be welcome.

I also want to add a normal value so that I can compress everything in two textures:

  • Diffuse and alpha texture.
  • Normal and 256-channel Z-precision texture.

I ask this question to find out what other directions you might think about and get your ideas on the right lighting equation that can be used.

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graphics 3d effects
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It looks like you are requesting information on modeling techniques for participating media : “Participating media can absorb, emit and / or scatter light. The simplest participating medium absorbs light. This means that the light passing through the medium decays depending on the density of the medium.”

Here are some links to some sample images and to the freezwad, Christensen, Jensen SIGGRAPH 2007 ( including PDF ).

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Good paper for using spherical billboards to represent volume effects:

http://www.iit.bme.hu/~szirmay/firesmoke_link.htm

Does not handle composite media.

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See Volume Rendering and Voxel .

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