I have created a Niagara particle system meant to represent a jet of water spewing from a firehose. When I enable collision to make the particles splash against the surface they collide with, a strange behavior emerges around the spawn point of the particles: slightly above where most of the particles spawn, additional particles are launched at an offset or immediately fall down. The exact nature of this behavior depends on the angle at which the other particles collide with the distant surface. I am attaching two images demonstrating these extra particles coming from the source – note also that if I rotate the collision volume about the x axis (roll it so the particles glance off to the left or right), these extra streams that are coming from the source seem offset left or right by a small amount.
Editor Version: 5.0.0-19206456+++UE5+Release-5.0
