Any tips on rendering out Open CL fluids to disk? The file sizes of the cashed frames are all various sizes that are the correct size for a 1,000,000 particle sim. The card makes it all the way through but the playback does not move at all when I load itinto the playback. CPU renders work fine. 680 Gtx with 4 gigs of ram. The sim only used 800 mb of going memory while computing.

Asking just in case you don't know. You realize when you browse to the SIM files you still have to put $F4 or $F in the file name to instruct the node to playback each frame.

I use the default.

$HIP/sim/$HIPNAME.`opname(“..”)`.$SF.sim

It writes the files out and when I open the sim with a DOP network using playback simulation as “show sequence as one entry”. It will properly load the sim for whatever frame I am at. When I change frames though, the fluid sim does not update. The sim appears to be stuck on the one frame.

It works here on osX. Test a on very simple sim please.

I did a simple test on OSX.
Sphere –> Flip Fluid
Ground plane

CPU the particles bounce as expected. GPU. They stick to the ground.
I'm not getting normal behavior.

Flip doesn't bounce in either GPU or CPU. Particles do, but they aren't OpenCL accelerated.

Yes. Sorry. I get correct fluid with CPU. Once I check the OpenCL on the solver the fluid just lands on the ground as it it was stick on collision, with no interaction with itself.

Reading any cashed fluid sim on OpenCL results in instability and Houdini crashes if I delete a DOP solver reading the sim. You

Yes! deleting the DOP network like that does crash. Please send in a bug report to SideFx, using the Support menu above. Thanks!

BTW you can avoid the SIM files and render a .bgeo in the created SOP nodes. Quicker and smaller files

I guess I was mistaken the whole time. I though OpenCL could be used for viscous fluids. That is my problem.

That's quite interesting - the docs say ‘OpenCL support for viscous fluid simulations.’, the ‘projectnondivergent_viscosity’ & ‘gas viscosity’ has OpenCL promoted, though, the ‘enforce_side_boundaries_viscosity’ Dop must be waiting on some code, as the OpenCL checkbox is not promoted.

I managed to solve the problem. There were a few things wrong. Thanks for your help. It was just a weird thing that was set wrong on my PC. But the Mac is a different story. I don't think i can use the GPU.