I'm a new Houdini Indie user, I'm coming from C4D + After Effects and want to exchange those two applications with Houdini, Fusion (and at a later time add Substance and a motion tracker to this workflow).
My problem right now is how to set up several render passes/ extra image planes correctly.
I have a scene with an object that disintegrates into particles and those particles make a new object. After searching for several days I have a setup that works for this particular project but I know that this won't be sufficient for future work and also I want to learn it correctly.
Right now I have three mantra nodes. One for my objects, one for my particles and one for the ground shadow matte. All render out the several channels to create a beauty pass and direct shadows. The ground has the Shadow Matte material applied. I tried doing it with no material assigned and simply use the direct shadow pass but it never worked properly.
Mantra seems to render the shadows into the Alpha Channel which I can use in Fusion but I can't change the colour of the shadows. If I use the direct Shadow pass Fusion won't use this correctly.
What I would like is having the objects and particles separate (It doesn't need to be separate files, could also be by using mattes) and a separate pass with all shadows. That way I can change the colour of the particles in Fusion and add different backgrounds. Basically what I have with the Shadow matte material except that I can manipulate the shadows more than transparency.
Every hint in the right direction would be appreciated. I tried reading the manual, searched through 10 years of Forums but couldn't find something that worked for me yet. (Maybe it's because I don't understand all the terminology of Houdini yet)
If I didn't make it clear about what I'm talking, or if this is simply a problem from Fusion or you don't have an answer to this particular problem, I still would love to hear how you set up your renders and what you use to composite.
I attached some screenshots so you get a better understanding of my scene.
Thank you all!
Edit 1: I believe I have found a way by using the Alpha or the shadow map as an alpha for a background in Fusion which I can then change the colour of. Nevertheless I'm still not sure if this is a “good” workflow or if I'm complicating things or increasing the render time unnecessary.