A particle emitter with GPU sprites on certain settings will shake violently as they collide with the ground. This requires there to be a strong Const Acceleration module and Collision with low resilience.
Yes, this issue doesn't occur in 4.11.2 Binary CL 2946394
I also tested on Main CL 3066218 and the issue doesn't occur
(To save time you can download attached project.)
#Open editor (blank project)
#Make a Material and Particle System
#Open Material> Set to Translucent
#Make a radial gradient exponential node> Plug into emissive and opacity
#Open Particle Sytem> Set the material in required module to the one you just made
#Set particle data type to GPU Particle
#Click Bounds drop down and click Set Fixed Bounds
#Add Const Acceleration Module> Set z value to -3000
#Add Collision Module> Set resilience to 0.2
#Set Lifetime to 3 on both min and max and Spawn Rate to 1
#Drag particle system into level and put it slightly above ground to allow particles to fall and bounce
Particles shake violently when landing on ground until they finally die.
Particles bounce lightly and then slide across ground without shaking.
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