Recreate the Starter Content Smoke Effect in Niagara

The Starter Content for Unreal Engine 4 (UE4) includes a smoke particle effect created in Cascade. In this how-to, you will learn how to recreate this Cascade smoke effect in Niagara. This example will help you move from Cascade to Niagara.

Create System and Emitter

Unlike in Cascade, Niagara emitters and systems are independent. The current recommended workflow is to create a system from existing emitters or emitter templates. However, since you are duplicating an existing emitter, the process will be slightly different.

1. Create a new folder for this How-To in the Content folder for your project.

2. Make a copy of the FX_Smoke emitter you created in Create a Sprite Particle Effect in Niagara.

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3. Drag this duplicate emitter to the folder you created in step 1. In the popup context menu, select Move.

4. Rename the copied emitter FX_DarkSmoke. This distinguishes it from the smoke effect created in the Create a Sprite Particle Effect in Niagara How-To.

5. Right-click on your new smoke emitter, and select Create Niagara System.

   There are multiple ways to create new Niagara systems. Because you are starting with an emitter you have already created, the method used here quickly creates a system containing that emitter. However, as you saw in the Create a Sprite Particle Effect how-to, there are emitter and system wizards that give you many other options for creating and setting up a Niagara system.

6. Name the system DarkSmoke. This is to distinguish it from the smoke effect created in the Create a Sprite Particle Effect in Niagara How-To.

7. Double-click the FX_DarkSmoke emitter to open it in the Niagara Editor. After you have edited the settings in the emitter, you will need to save the DarkSmoke system also.

8. Drag the DarkSmoke system into your Level, so you can preview the changes in the context of your project's world.
   

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   When you make a particle effect, it is always a good idea to drag your system into your Level. This gives you a chance to see every change and edit in context. Any changes you make to the system automatically propagate to the instance of the system in your Level.

Edit the Emitter Update Settings

First you will edit the modules in the Emitter Update group. These are behaviors that apply to the emitter itself, and that update each frame.

1. In the System Overview, click the Emitter Update group to open it in the Selection panel.

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2. Expand the Emitter State module. This module controls time and scalability for this emitter. Because you used the Simple Sprite Burst template, the Life Cycle Mode is set to Self. Normally this is used for complete customization of emitter life cycle logic for this specific emitter, but it is not needed for this effect. Click the dropdown and set the Life Cycle Mode to System. This enables your system to calculate life cycle settings, which usually optimizes performance. By default, the system loops infinitely on a 5 second interval.

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3. Open the Spawn Rate module. Set the Spawn Rate to 25.

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Edit the Particle Spawn Settings

Next, you will edit the modules in the Particle Spawn group. These are behaviors that apply to particles when they first spawn.

1. In the System Overview, click the Particle Spawn group to open it in the Selection panel.

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2. Open the Initialize Particle module. Under Point Attributes, expand Lifetime. The Lifetime parameter determines how long particles will display before they disappear. Change the Minimum and Maximum values to the following.
   

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   Parameter	Value
   Minimum	3.0
   Maximum	5.0

3. Expand Color. Change the RGB values to the following:

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   Parameter	Value
   Red	.208
   Green	.208
   Blue	.208

4. Under Sprite Attributes, expand Sprite Size. Change the Minimum and Maximum values to the following:

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   Parameter	Value
   Minimum	50
   Maximum	90

5. Open the Add Velocity module. Change the Velocity Minimum and Maximum values to the following:

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   Parameter	Value
   Minimum	X: 12, Y: 0, Z: 5
   Maximum	X: 32, Y: 0, Z: 7

6. Open the Sphere Location module. Change the Sphere Radius value to 30.

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Edit the Particle Update Settings

Now you will edit the modules in the Particle Update group. These behaviors apply to an emitter's particles and update each frame.

1. In the System Overview, click the Particle Update group to open it in the Selection panel.

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2. Open the Acceleration Force module. Set the Acceleration Z value to 20.

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3. Open the Scale Color module. Add a third key to the Scale Alpha curve by right-clicking the curve line and selecting Add Key to Curve.

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4. Set the three keys to the following values.

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   Key Number	Time	Value
   1	.08	.3
   2	.16	1.0
   3	.68	.3

End Result

After following these steps, the Smoke system in your level will produce a smoke effect similar to the one in the video below. In the video, you can see the Cascade particle system on the right, and the Niagara equivalent on the left.