I want to create a particle system that spawns a single particle that scales from zero size to a constant size over the first two seconds, then holds that size indefinitely. Unfortunately, if I want to create a particle with infinite lifetime, I have to set lifetime to 0. This means I can’t use size by life, since the age of the particle is always 0. I could set the lifetime to a very large number, which would work, but then I can’t use size by life, since it maps 0-1 to the birth and death of the particle.
So I’d like to use something like a “size by time” module, where I can set it to scale over a fixed time, rather than the particle lifetime.
Sadly by time has been removed when bringing cascade from UDK over to UE4.
So all you can do is hope that they bring it back once niagara becomes available.
What you can do however, is duplicate your particle, and give it a delay of two seconds.
so particle 1: lifetime of two seconds, grows to X size.
Particle 2 spawns the moment particle 1 dies, takes over its place infinitely timewise.
Hm. That’s what I’ve done for now, but it’s not ideal, since I want these to be randomly-tumbling mesh spheres. I could probably work around this with seeded rotation, and possibly with a warmup module.