Wednesday, April 28, 2010

Water treatment by John Moncrief

1 comment:

  1. Josh and I started off using Real Flow 4, but as the R&D progressed we were able to move the simulations into Maya to optimize the back and forth in the pipeline.

    This allowed us to develop a set of tools that gives the animation team real time interaction with the water surface as the characters move.

    We are using Reanderman which does not render Maya fluids by default, so we are developing a system that ties dynamically ties a poly mesh to the fluid surface. This way using either a pre-render script or a custom switch in the chan box the lighting and rendering dept. can switch off the Maya fluids and see the poly surface on demand.

    Another great discovery was that Renderman WILL render sprites, points, multi-points... all the particle types that Maya requires hardware rendering for. This means we don't have to composite in the spray post render, how cool it that!

    There was also an issue with particle collisions and Maya's pond wake emitter. Basically it doesn't exist!

    To solve the issue we developed an expression that would evaluate the emitters proximity in Y to the pond surface and only spit out the spray when the object is in contact with the pond. (Special thanks to Duncan Brinsmead at Autodesk for giving us a push in the right direction... man that guy is smart!)

    This also gave us the ability to adjust and key frame the collision distance and emission rate of the emitter. If you want some trailing drops of spray to "drip off the object as it pops out of the water... just turn up the collision distance and the object will keep making spray even though it is out of the water a bit.

    Keep in mind these are just some prelim test renders. We'll update the renders as we progress.