Hello, I'm trying to use near/far clipping planes on a camera to render a volume and comp something in the middle.. the problem is, when the far clipping plane is right in the middle of the volume (ie the front part of the fire), the far clipping plane is ignored. If the volume is hidden, I can get the front part right.
Right image is using the same far clipping plane as the left part, just with a hidden volume
I'm not sure if I have to do add something to the ROP in order to make it work ops:
I'm not sure how to solve your problem with clipping planes, a matte object will do that. Create a grid that's where you want the clipping to be, and make it large enough to completely cover the back part of your volume, and set that to be a Force Matte object on your Mantra ROP.
Yes, that also works. Thanks for the tip. I ended up using the ‘matte shading’ parameter in render tab of a grid object, so it is almost the same
I've found that this problem is triggered because there is no density field group in the bgeo file. Creating a new primitive named density and copying existing data will solve the issue. http://i.imgur.com/zrODQKX.png [i.imgur.com]
What node should I use to create an empty primitive in this volume object, name it and then copy existing primitive to this one?
edit: the proper way of compositing geometry in the middle of a volume is to use deep camera maps :roll:
ops: 
