Freezing a Sim for Clouds

[tommygdawg]

Hey all,

Would seem to be a fairly simple question that I'm having a hard time finding a good answer to. I want to do clouds and nebulae, what would be the best way to do this? I've read that simulating fluids and then animating the time scale would work for changing the speed, but would animating to 0 effectively freeze the sim at whatever frame I'm at? Any thoughts would be appreciated!

Thanks,
- Tommy

[Ivaylo Katev]

just use "direct frame" input mode and set the direct frame index parameter

[tommygdawg]

Woah, this changed my life, and it's so simple! Thank you so much!

[möbius]

btw, this might be a noob question but dos the phoenix grid actually need to simulate to make the voxels visible? let's say i emit particles into the grid and just want phoenix to render static voxels around every particle within a defined radius without producing any simulation data.

[Svetlin.Nikolov]

Well, you've got to simulate at least a little even in that case Drop the conservation quality to 1, steps per frame to 1 (both of these to make the simulation faster), use a source in brush mode with 100 discharge to print the particle volume into the grid and use a radius on the particles or attach some geometry to them. Also, you need to choose "particle shape" at the bottom of the PHX source, if you have geometry attached to each particle, or otherwise if you need just spheres, use "use size, sphere".

This setup will do if you simulate just one frame. If you simulate many, make sure in the Dynamics tab you set the 'smoke dissipation' to the max, so the smoke from the previous frame will disappear completely.

To make more interesting clouds, especially if you don't want to see them moving, you can then use the Displacement options in the Rendering panel, but beware that the rendering may slow down significanlty.

[möbius]

Cool Thanks! I tried it this way and here is the result. I think it looks quite decent:



This is a screenshot from the GPU preview in the Viewport btw, thank you guys for that, too

[Svetlin.Nikolov]

Wow, nice! Great job

[magilla]

looks great

[möbius]

Thank's guys.