05-17-2007, 03:01 PM
Hi everybody
I've been having some issues getting subframe sampling to work correctly when loading FFX data into a particle flow system.
Essentially, when the particles are generated by the FumeFX Birth operator they don't seem to be subframe sampling and I get little 'puffs' of particles on each frame.
I've tried a bunch of different ideas to get more smooth particle birth with varying levels of success. Probably the most time consuming and what I thought would be the "most likely to succeed" approach was to run the FFX sim with the steps set to 4 so it would calculate the velocities every 1/4 frame. Then in PF, I set the Integration Step to 1/4 frame in hopes that it would utilize the additional subframe data. This idea had no success. It took 4x longer to sim and 4x longer to render the exact same "puffy" result.
A more 'brute force' approach was to make use of a speed operator and an age test to fire the particles out in random directions for one frame after they are born and then feed them to the Fume Follow operator. This was more successful in the sense that I only needed to use the single step simulation and it resolved the 'puffy' emission problem, however all the really cool swirling FFX motion starts to get lost/fuzzed out by the random speed.
Anyway, I can probably send a sample scene if that would help. It's basically an elongated sphere that's spinning and traveling on a path while it emits smoke. I simulate it with velocity and temperature added to the exported channels. Then using FumeBirth and FumeFollow operators in PFlow, I load particles and render them.
Thanks
- Conrad
I've been having some issues getting subframe sampling to work correctly when loading FFX data into a particle flow system.
Essentially, when the particles are generated by the FumeFX Birth operator they don't seem to be subframe sampling and I get little 'puffs' of particles on each frame.
I've tried a bunch of different ideas to get more smooth particle birth with varying levels of success. Probably the most time consuming and what I thought would be the "most likely to succeed" approach was to run the FFX sim with the steps set to 4 so it would calculate the velocities every 1/4 frame. Then in PF, I set the Integration Step to 1/4 frame in hopes that it would utilize the additional subframe data. This idea had no success. It took 4x longer to sim and 4x longer to render the exact same "puffy" result.
A more 'brute force' approach was to make use of a speed operator and an age test to fire the particles out in random directions for one frame after they are born and then feed them to the Fume Follow operator. This was more successful in the sense that I only needed to use the single step simulation and it resolved the 'puffy' emission problem, however all the really cool swirling FFX motion starts to get lost/fuzzed out by the random speed.
Anyway, I can probably send a sample scene if that would help. It's basically an elongated sphere that's spinning and traveling on a path while it emits smoke. I simulate it with velocity and temperature added to the exported channels. Then using FumeBirth and FumeFollow operators in PFlow, I load particles and render them.
Thanks
- Conrad
I moved here from Canada, and they think I'm slow, eh.