Rendering dust - how to leave sections out of the render?

[Deflaminis]

I'm looking for a way to not render these circled red areas where the car tire never really touches and they don't have any speed or motion. I'm not really sure the best way to go about it. I tried density by speed but I'm a bit lost. Thanks for any tips.



Best Regards,
AJ

[Ivaylo Katev]

how the dust appeared in the red zones?

[Deflaminis]

Well I probably did this wrong but what I did was emit the dust off a plane at like 280 degrees temp and then ran the car through it hoping to raise some hell. What I didn't count on was the everywhere effect. I was trying to only really show something where there was tire contact, but I'm just not sure how to approach it. (I guess because it's dust instead of fire/smoke.)

I wonder if I could use a vray distance tex and select the tires and set it to a discharge map or something... maybe even vray dirt... as the area for emission as the car rolls by. Probably more accurate.

What would you do? Thanks!

[Ivaylo Katev]

the distance texture was exactly what i would suggest

[Deflaminis]

Thank you! Seems to be working great. Appreciate it!