PopcornFX is a great tool for realtime applications in that it brings to developers a ready-to-integrate particle system which can be used to author sophisticated effects in a nodal/visual style akin to Houdini, ICE etc. I find it much more intuitive than Niagara while easily being as powerful, and it’s integration into After Effects brings those users a level of sophistication with particle effects they simply haven’t had access to before. That said, when I push the limits it understandably can’t chew through the millions of particles Houdini can handle.
For example in PKFX this frost-like propagation effect, which is admittedly computationally expensive, tops out in usefulness at about 50,000 particles. The in-editor framerates are still good (relatively speaking) at 220 ms, comfortable enough for cinematography work in After Effects for example. But when you push the number of particles up beyond that times go up exponentially. By 100k particles (for this particular task, which involves getting neighboring particle information) the editor becomes increasingly likely to crash.
But to be fair this kind of propagation effect is waaay beyond what most realtime engines are engineered to handle. Other effects in PopcornFX can get into the realm of millions of particles without too much trouble, which means those After Effects users have a system which lets them perform most particle effects they are likely to need extremely efficiently… and only need to go to a package like Houdini for the really intensive stuff.
And at the moment these computations are only on the CPU as PKFX is still implementing its GPU support. There is a lot of improvement on the near horizon for these kinds of intensive effects… we may see sph fluids and the like running realtime soon enough.
(It’s also worth mentioning that there is a LOT of room to optimize the effect as built, both with regular settings and as one of the PopcornFX devs points out massive increases in efficiency should be possible by only performing spatial queries on the particles changing values and depositing stable values into a static layer.)
It’s significant that those integrating PopcornFX into realtime tools get a system sophisticated enough that a comparison with Houdini is even possible.
In all, I’m pretty impressed with PKFX and as an effects guy would welcome jobs where it’s integrated into custom pipelines dealing with realtime media even over Niagara and certainly over Unity’s particle system. It is elegant to use without sacrificing power, and it’s universal nature means one day artists might be able to share and use particle assets across multiple engines and custom pipelines.