UE4/Class PopcornFXEmitter

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! IMPORTANT ! This is a PopcornFX v1 page. PopcornFX v2 UE4 plugin documentation can be found here

(last edit version: v1.0.0-preview-5)

Class PopcornFXEmitter

A PopcornFXEmitter is an actor that will spawn an instance of a PopcornFXEffect.

They are updated and rendered in a PopcornFXScene, allowing group control over emitters.

PopcornFX Emitter Actor

  • If you drag and drop a PopcornFXEffect in the scene, a PopcornFXEmitterActor will be automaticaly created.
  • When selecting an emitter actor in the world outliner, you will be able to edit its properties

Ue-drag-and-drop.gif Ue-emitter.png

Emitter properties

  • Emitter Actions : Lets you respectively Start/Stop/Restart this PopcornFXEmitter
  • Effect Actions : Lets you either Reload or Reimport the PopcornFXEffect
  • Effect : The PopcornFXEffect to spawn with the current emitter
  • Enable Updates : When checked, the PopcornFXEffect transforms will be affected by your current PopcornFXEmitter
  • Play on Load : To start this PopcornFXEmitter if it is loaded in the scene
  • Scene Name : The PopcornFXScene in which this PopcornFXEmitter should render and be updated

Attributes properties

This part of the emitter's details panel lists the effect attributes and and attribute samplers.

You will be able to tweak each attributes depending on their type.


An attribute description tooltip is displayed if you hover an attribute.

Quick Tip: Disable Editor's throttle

The Unreal Editor sometimes blocks viewport updates when Slate events occur (changing a values, clicking buttons, ...)

This results in blocking the viewport update when tweaking attribute values, and can be annoying for fine tuning.

To disable this, enter the following command:

  • Slate.bAllowThrottling 0



To manually create a PopcornFX emitter, you can:

  • Create a blueprint that inherits from PopcornFXEmitter
  • Add a PopcornFXEmitterComponent inside an existing blueprint
  • Spawn an emitter with PopcornFX functions, fire and forget (see below)

Different functions are available on emitters

Ue-blueprint-graph-emitter.png Ue-blueprint-graph-attributes.png

Emitter Functions

These functions allow you to modify the emitter state and create new instances.

  • Copy and Start Emitter at Location : Creates a copy of your emitter, and spawn it at a specific location and rotation (fire and forget)
  • Copy and Start Emitter Attached : Creates a copy of your emitter, and spawn it at a specific location and rotation, attached to a specific parent (fire and forget)
  • IsEmitter Alive / Emitting / Started : Helper functions to determine the current status of the emitter
  • Restart Emitter : Restarts the emitter (Terminate + Start)
  • Set Effect : Changes the source PopcornFXEffect of the emitter
  • Spawn Emitter Attached : Spawns an emitter at a specific location and rotation, attached to the specified parent (fire and forget)
  • Start Emitter / Stop Emitter : Respectively starts and stops the emitter
  • Terminate effect : Stops emission and unregisters the emitter
  • Toggle Effect : Starts or stops the emitter, depending on the given parameter

Here is an example of how to spawn an emitter (fire and forget):


Attributes Functions

These functions allow you to manipulate the emitter attributes.

  • Find Attribute Index : Returns you the index of a specific attribute name
  • Get Attribute : Generic function to retrieve an attribute value
  • Reset Attributes to Default / Reset to Default Value : Reset your emitter attributes to their default values
  • Set Attribute : Generic function to modify an attribute value

Here are examples to Get / Set an attribute value

Ue-bpgraph-attributes-functions-1.jpg Ue-bpgraph-attributes-functions-2.jpg