Why does my Niagara Stage with Fixed Iteration produce no output?

Iteration Count is zero or Stage Source isn't set. Configure: Stage Source = Particles, Iteration Count > 0. Stage runs that many times per tick.

Custom processing pass beyond Spawn/Update. Useful for spatial hashing, simulation passes, pre-process before particle update.

Stage Source = Direct Set?

Stage operates on a Direct Set data buffer rather than Particles. Useful for grid-style simulations where each iteration writes to a unique cell.

Fix: Niagara Stage Fixed Iteration Outputs Nothing

Quick answer: Stage Source = Particles. Iteration Count > 0. Direct Set source for grid-style sims.

Custom Niagara Stage runs but produces no visible effect. Iteration Count was 0 by default.

The Fix

Niagara Stage:
  Stage Source:               Particles
  Iteration Count:            10
  Disable Reset:              false
  Enabled:                    true

Stage modules:
  + Custom HLSL or Set Attribute
  Process per particle

Iteration Count multiplies the work per tick. Stage Source defines what data the stage walks (particles or fixed buffer).

Verifying

Stage runs visibly. Niagara Debugger shows iteration count, modules executed.

“Source set. Count up. Stage runs.”

Related Issues

For Niagara Data Channels, see data channels. For Stateless emitter, see stateless.

Source. Count. Stage runs.