First VFX workflow Q

Hello good people,

Im working on my first effect and ran in to workflow problem. Effect is pretty common, “Spike trail” like Lurker attack from Starcraft 2 or anub’arak skill shot in heroes of the storm.

My workflow:

  1. Modelled and painted the spike
  2. Animated and simulated spike braking through the ground in Houdini.
  3. ?

Based on recent tutorials I can actually use simulated geometry from Houdini in UE4, but I could not plug it in to Particle emitter, because it is mesh with skeleton and animation.
Am I missing something or better use simulated geometry just as reference and try to replicate it with mesh emitters?
How would you recommend approaching this?

As always with this kind of thing there’s lots of ways to approach this and various advantages and disadvantages of such:

1, Export a Mesh for the Spike then manually keyframe the movement and secondary effects in Cascade - basically the most ‘old-school’ method, not what i’d do for a modern UE4 game but probably what represents what most in-house engines would be doing. Time consuming with lots of hard coded duplication.

2, Set up the Mesh and Ground Pieces to use Vertex Animation instead of Skeletal Animation (this will involve baking the Vertex movement to a texture) - this then means you can use a Mesh Emitter in Cascade and drive the timing of the animation with a Dynamic Parameter. This will give you a better quality animation but takes additional time in the setup.

3, Set up a single Spike effect using either of the above methods and then use a Blueprint to trigger off as many as you want with an offset. This adds a bit of complexity but also gives the Designers much more freedom to iterate and saves you time editing the effect if things like the Length change, due to balancing changes or in game upgrades etc.

4, Similar to the Blueprint above but actually just animate the Spike in Blueprints (either with a Static Mesh and a Timeline or with a Skeletal Mesh) and just use Cascade for the supporting effects - I’m a big fan of this sort of combined approach - its a bit more work to set up but the advantages make it worth it imo.

Hope that helps - if you’re just starting out learning then I’d maybe recommend trying all the methods out and seeing for yourself what sort of benefits each offers.

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