Hello, i am a little new to unreal engine got a good grasp of it. As of now, I have been trying to figure out if there is a way to reverse a particle effect in UE4?
This has the ability to pause the particles in place, but I was wondering if there was a way to reverse the particle effect \ spawn?
e.g. an explosion particle going from big burst to nothing instead of regular exploding
It’s possible, but it requires a bit of creative thinking.
A few tips to create an effect like this;
When animating alpha/color, you can simply just reverse the keys. Instead of alpha ending at 0, it starts at 0.
Likewise, scale by life is the same. Start small, end big.
Velocity is more tricky, as it depends on where the particles need to go. If the particles would originally spray out from a single point into all directions, what you can do is create a sphere as initial location (maybe have all the particles spawn on the surface of the sphere) and use an attractor to draw your particles to the center. To make them disappear at the center, you can use a small killbox to remove them once they get there.
Smoke trails are most tricky. I cannot think of anything that may create a “reverse” smoke trail, because your smoke will have to end up following the particle they follow. Hard to reverse that. Maybe in Niagara (Unreal 4.20) something like this is possible (for instance, maybe by having particles follow a spline, in which case you can simply reverse the starting point. Not sure if that’s possible though), but in regular Cascade I have no idea.
The way as I see it, you shouldn’t think of it as “reversing” an existing particle system. You should think of it as a different particle system, which just happens to go in reverse.