Planar objects with opacity maps matteing out the fume smoke

[Suspensa]

I have a scene with steam coming out of a manhole with a series of planes in front of and behind the fume object, but not intersecting, with animated opacity maps to represent rain and also have a planar object along the road with animated opacity maps for running water that also dont intersect the fume grid (in 3 space anyways). When I render the scene, the fume smoke gets cut off by the planes. There is a visible line where it cuts it off. If i hide the rain and or water planes the smoke renders correctly. I've run into this problem before with objects with opacity maps. What causes this and how can I get around it?

Thanks,

Spencer

[Rif]

Hey spencer , what renderer are you using ?

I v ran into similar things using Raytracers with Fume and Opacity maps.. its normal exceptions with Max atmospherics .. In Fr , their is in general tab something to uncheck about Atmospherics and Gbuffer extracts witch solved alot of my problemes with hold outs and RE extracts and etc..

If your using streight Scanline renderer , i think i m missunderstanding your post then and i think the best thing to do is to post either here or on cgfluids a simple scene similar to what you have and will take a look at it no prob

cheers,

[Suspensa]

I'm using Final render R 2 with the adaptive QMC. I thought maybe it was something in the FR properties on the individual objects but didnt find anything to get it to work. I'll look into the check boxes about atmospherics to see what I can find.

Thanks,

Spencer

[Rif]

ok if you cant fix it , please post a scene and will take a look at it.. Joe , ari and me are in Fr as well ..
cheers,

[Suspensa]

I had no luck finding the right settings to make this go away so here is a link to a stripped down version of the file in question (Can't release the full file as you probably understand).

http://user.sancsoft.net/Steam01.zip

In the zip is included the maps used for opacity with the objects oriented the same as in the scene i'm having trouble with. There is also a folder with 2 frames of the fume sim to show what is happening. The total file size is 15 mb. Any help would be greatly appreciated.

thanks,

Spencer

[Rif]

ok a quick look at it seems to tell me that its might be a bug in fume.. heres a Scene that i striped down everything to the minimum with scanline renderer that shows the fluid looking behind the object in the render while been in front of it in the scene..Youll have to use your Fxd in the grid of course to see it


the scene is passed on to Kreso .. maybe i m missing something here..

[Suspensa]

Yeah I also thought I might be missing something, but I have yet to figure out what that something is. I've tried different mapping techniques, rendering settings, etc, but haven't been able to solve it. I can just composite the fume smoke in the meantime, but at this point I'm just curious to see what the solution is.

Thanks for the help,

Spencer

[sitnisati]

Hello,

For the Object "Steam_ConduitCollision" you have to set it to Shell, instead of Solid.
If it is solid, smoke cannot go anywhere. What you see is an expected results when you scrub the time slider after simulation.

Regards,

Kresimir

[Rif]

ok kreso , but what about the smoke beeing renderered behind the object in rendertime while in 3d clearly infront of it ?

[Suspensa]

If I render it without the rain planes it renders fine. The conduit collision object is already shelled so if i use "solid" it behaves the way it should. It seems like its some sort of matteing/ zbuffer issue.

Spencer

[Rif]

Spencer , open my scene and tell me if you get this result witch is not fine without the rain plane :

[Suspensa]

Sorry, the StreetWater object also mattes out the fume like in your file.

[sitnisati]

In matte material - did you try to change Apply Atmosphere at "Background Depth" ?

Kresimir

[Rif]

thats the probleme.. its not a matte material!
i m pretty sure their is something wrong somwhere..

[Suspensa]

Well i've tried using a blend material with the Transparent material as a matte/shadow and the opacity map as the mix map, but that also didnt work. I'm stumped.

[sitnisati]

thats the probleme.. its not a matte material!
i m pretty sure their is something wrong somwhere..

Rif, in your scene, it is a shadow/matte material.


It seems that object has Apply Atmosphere off !
You see that if you collapse it's modify stack.

[Rif]

ya i see it.. Spence , please dont ever uncheck that hock:

alright no bug their then .. thats most likely why you have your plane in front as well doing this ..

[Suspensa]

Thanks for all the help. It's usually something small and obvious that I stumble over. I must have unchecked it to keep the fog filtered out. Oops. Sorry for wasting so much of your time! BTW, Fume rocks! Keep up the good work!

thanks,
Spencer

[sitnisati]

You're welcome to post anyhing you find suspicious in FumeFX operation.
This time, it was a user error, but next time...