I have a very basic setup of a cube as a floor, and a niagara upwardmesh burst system configured to look like coins bursting and falling to ground. they work fine, hit the ground and bounce around before settling. I can use this setup in many different levels and I have already. I’m working on a new level that has a bunch of stuff already, I add the coin burst niagara and it falls through every mesh i put in its way. I also have another niagara system for bullets that have impact vfx when the bullet collides with the wall. again this works in every level i can try it in, ones ive made, ones ive downloaded from market. then i try it in my current level i am working on and the bullets just go through the walls. its as if niagara collision isnt working in this level that i need it to. but I have not done anything different setting this level up than my previous levels. collision is enabled, ive checked all the meshes, I can copy paste the cube floor and niagaras to a new blank level and they just work the coins hit the ground, the bullets impact the walls. but in my main level the same exact setups are not colliding. same meshes same niagaras…im lost.
There are a few possibilities, so the best I can do is list many. You’ll need to check what may or may not be active for your project. See the Google results below:
Niagara particles might fail to collide with walls in UE5 due to incorrect collision modules, missing global distance fields, or faulty emitter bounds. To fix it, ensure your Collision module is the last node before Solve Forces and Velocity, enable Distance Fields in your project settings, and tweak particle size. [1]
How to Fix Niagara Particle Collisions
1. Module Placement (Order of Operations)
The order of modules in the Particle Update stage heavily influences collision accuracy. [1]
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Open your Niagara System and go to the Particle Update stage.
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Click the
+icon and add the Collision module. -
Drag the Collision module so that it is positioned immediately before the Solve Forces and Velocity module. These should ideally be the very last modules in your Particle Update stack.
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Inside the Collision module, set your collision mode (e.g., Distance Field for GPU or World Ray Tracing for CPU). [1, 2, 3, 5]
2. Enable Mesh Distance Fields (For GPU Particles)
If you are using GPU-simulated particles (common for heavy effects), collisions will not work against your walls unless Global Distance Fields are enabled in your project. [1]
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Navigate to Edit > Project Settings.
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Search for Generate Mesh Distance Fields (found under
Engine - Rendering>Lighting) and ensure the box is checked. -
Note: You will need to restart the editor for this to fully apply.
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To improve collision accuracy, you can also increase the Collision Radius Scale slightly in your Niagara Collision module to prevent fast particles from phasing directly through thin walls. [1]
3. Adjust Emitter Fixed Bounds
If your particles are suddenly passing through walls or disappearing when looking away from them, your Emitter Bounds might be too restrictive. [1, 3]
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Select the Emitter in the Niagara viewport and check the Emitter Properties panel.
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Ensure your Sim Target is set correctly for your setup (CPU vs GPU).
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Under Fixed Bounds, increase the size of the box. You can view the bounds by enabling Show System Bounds in the Debug/View options to make sure it covers the entire path of your wall collisions. [1, 2, 3]
4. Check Wall Physics Settings
If the particles collide but bounce off erratically or phase through at high speeds, physics variables might be the culprit: []
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Select your wall static mesh in the Level Viewport.
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Check its Collision Complexity. Set it to Use Complex Collision As Simple (or make sure you have an appropriate custom collision box built around the wall) to prevent gaps in the collision volume.
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Inside the Niagara Collision module, adjust Damping and Friction under the Collision Response settings to control how the particles behave upon impact.