kyphur
02-03-2003, 03:23 AM
I need to get paint FX to show up in PRMan and there was a deal on High End 3D that Pixar points to for this problem:
URL: http://www.highend3d.com/maya/tutorials/paintfxqa/b.3d
Transferring Paint Effects to RenderMan
Q: Is there some kind of RenderPass (ala Fur) that happens in the renderer..(and here’s the real reason for the question..will any instanced geometry pass over to say RenderMan?)
A: The render method is similar to fur. It is a zbuffer based post process. For hair, vines and such, the tubes are never kept in memory, but rendered or drawn(in model view) on the fly. If you wish, you can create a mel function to output the positions of the generated tubes(along with color, transparency, etc) to a file. The brushnode has 2 mel callbacks you can set: creation and runtime. The runtime function gets called for every segment of the tube, and gets passed in the segment location, width and shading info. Your script might be a little work to set up, however. For simple brushstrokes the path curve is identical to the drawn tube, and so you could use this curve's data directly. You can also render separate paint effects passes for compositing. For the best quality composite, you could load in a depth and rgb render( from RenderMan ) as a background imageplane in Maya and render the paint effects onto this. In particular volumetric and glow shading effects will work better using this method.
So what I would like to know is if anyone knows if anyone has a similar mel script for download or am I going to have to write my own (I'm not great at code).
If anyone knows where I can get this or wants to help me out with writing the code and testing it please let me know.
Kyph
URL: http://www.highend3d.com/maya/tutorials/paintfxqa/b.3d
Transferring Paint Effects to RenderMan
Q: Is there some kind of RenderPass (ala Fur) that happens in the renderer..(and here’s the real reason for the question..will any instanced geometry pass over to say RenderMan?)
A: The render method is similar to fur. It is a zbuffer based post process. For hair, vines and such, the tubes are never kept in memory, but rendered or drawn(in model view) on the fly. If you wish, you can create a mel function to output the positions of the generated tubes(along with color, transparency, etc) to a file. The brushnode has 2 mel callbacks you can set: creation and runtime. The runtime function gets called for every segment of the tube, and gets passed in the segment location, width and shading info. Your script might be a little work to set up, however. For simple brushstrokes the path curve is identical to the drawn tube, and so you could use this curve's data directly. You can also render separate paint effects passes for compositing. For the best quality composite, you could load in a depth and rgb render( from RenderMan ) as a background imageplane in Maya and render the paint effects onto this. In particular volumetric and glow shading effects will work better using this method.
So what I would like to know is if anyone knows if anyone has a similar mel script for download or am I going to have to write my own (I'm not great at code).
If anyone knows where I can get this or wants to help me out with writing the code and testing it please let me know.
Kyph