How to do tracks in dirt, mud, snow, and tire marks?

3D4Eva

What are the current methods to accomplish tracks in dirt, mud, snow, and even tire marks on roads? I can only think about using particles to displace the terrain geometry underneath by using the actual geometry of the tire tread to drive it, and maybe a trailing graphic but I'm really unsure how generally this is done?

I have access to Maya and Houdini.

poopipe

In a game you'll basically drop a trail of particles or a ribbon behind the tyre with a picture of the tread on it and use that to displace/affect color etc. 

For close up film work I imagine you'll be using a metric shit ton of particles

Eric Chadwick

Some vids in here that might help.
https://polycount.com/discussion/221349/terrain-animation

3D4Eva

Thank you!

RN

On snow and sand there are these techniques some games have tried (edit: well, tried and succeeded!), but they are very complicated:

• Effects Techniques Used in Uncharted 3: Drake’s Deception (page 49)
• Deformable Snow Rendering in Batman™: Arkham Origins (page 10)

3D4Eva

What is the main technique for film?

RN

For VFX I think that's either an animated displacement map, or particles that react to an animated surface or object, but if you search for how to do that in Maya or the program you're using, you'll definitely find it.

This is a couple screengrabs from this page here, note how they only laid out particles on the region that the actors would go through. No need for the whole ground to be made of dynamic particles.

3D4Eva

Thank you!