I'm a concept artist in the game industry looking to generate explosions & fire stills for use in my matte-paintings. Is there a way to streamline Houdini's workflow if I only need still frames instead of an animation sequence? The tutorials make calculation time seem like a real pitfall, but they're all making animation sequences instead of the stills I intend to make.


As a bit of background: I use a lot of 3d for my work [mattkohr.artstation.com], so I'm not concerned with the learning curve. Modo and Octane have spoiled me with fast rendering, so I'm accustomed to very little ‘waiting’ while I design. But Houdini's Pyro solver looks… amazing. Being able to light realistic smoke, move the camera, and render out a few .pngs….. that's something that photo reference will never compete with.

Thanks in advance for the help!

Sadly, the way a solver works (in a very simplified way) is by taking the previous frame and modifying it with the different parameters that you feed it, so no, there's no way that I know at least to use pyro to create explosion still frames without having to actually calculate all the frames before the one you want. Furthermore, in production plenty of times we find ourselves having to simulate on the “preroll” (frames that are outside of the shot range) to be able to get the starting frame of the shot to look how the client wants it.

You could however use other tools inside Houdini to manipulate a volume and make it look like what you're looking for, but the result of course wouldn't be the same.

Well, it depends. Houdini still needs to be able to calculate a fireball as it expands and travels even if you're only intending to render out a single frame of it. Basically it depends on where in the fireball lifecycle you would like to render from.

Calculations aren't terribly time consuming depending on the complexity that you need, but of course a fast machine helps.

I'm currently on a 4-core i7 6700k and I'm eager to update to a 10 core i9 soon to alleviate some of the issues.

if you do choose to go the Houdini Pyro route…realise that you could do what many of the studios do and write out a variety of sims to a library…that way if you needed some chimney smoke, you could bring is a sim from the library and pick the frame (every frame could be thought of as a different shape) you wanted > render to image and use that…etc.