Mental Ray parti_volume not real volume?


#1

I’m filling some arbitrary geo shapes volumetric shading. I’ve never had good results with mental rays parti_volume and it’s not any better this time.

It doesn’t look like it’s a true volume.

I applied it to a cube and textured the scatter to test and I would expect to see actual volume inside the cube as if it was a fluid container. The result i get is almost identical to applying a 3d texture to the transparency of a lambert. It’s only visible on the outside edges of the volume.

It’s done the same thing when I tried light rays for another project, but I was able to get away it. Putting the camera inside the volume makes the effect even worse.


#2

Hi!

Unfortunately I’m about to rush out the door, but I did a bunch of tests recently around parti volume and even the old Maya volume primitives and it is possible to get it working properly, it’s just not intuitive. There’s a magic step which I think is turning on depth jitter on the shape node or something. Then suddenly it will work as expected.

If you can’t get it working I’ll reply again tonight!

EDIT: I said volume jitter but I meant depth jitter.


#3

ahh, good to know! Thanks! I’ll give it a shot.