How to Make a Blinking Light in Unreal Engine

How to Make a Blinking Light in Unreal Engine

by

This guide teaches you how to make a blinking light in Unreal Engine using Blueprints, materials, and timeline nodes. Perfect for game developers of all levels, it covers multiple methods with clear instructions.

Key Takeaways

  • Use Blueprints for dynamic control: Unreal Engine’s Blueprint system lets you create blinking lights without coding, using visual scripting.
  • Leverage the Timeline node: The Timeline node is ideal for smooth, repeatable blinking effects with customizable timing.
  • Adjust light intensity and color: You can make lights blink by changing brightness, color, or both for more realistic effects.
  • Apply materials for emissive blinking: Use material parameters and scalar values to make surfaces glow and blink over time.
  • Optimize performance: Avoid overusing tick events; use timers or timelines to reduce CPU load.
  • Test in different lighting conditions: Always preview your blinking light in various environments to ensure visibility and realism.
  • Combine methods for complex effects: Mix Blueprint logic with material animations for advanced blinking patterns like strobes or pulses.

Introduction: Why Blinking Lights Matter in Game Design

Lights are more than just visual effects in games—they set mood, guide players, and add realism. A blinking light can signal danger, indicate a power surge, or simply make a scene feel alive. Whether you’re building a sci-fi spaceship, a haunted house, or a city street at night, knowing how to make a blinking light in Unreal Engine is a valuable skill.

In this guide, you’ll learn multiple ways to create blinking lights using Unreal Engine’s powerful tools. We’ll cover Blueprint scripting, material editing, and timeline animations—all without needing to write a single line of C++ code. By the end, you’ll be able to add dynamic, eye-catching lighting to any project.

This tutorial is designed for beginners and intermediate users. You don’t need prior experience with Unreal Engine, though basic familiarity with the interface helps. We’ll walk through each step carefully, with tips and troubleshooting advice along the way.

Let’s get started!

Method 1: Blinking Light Using Blueprints and Timeline

How to Make a Blinking Light in Unreal Engine

Visual guide about How to Make a Blinking Light in Unreal Engine

Image source: i.ytimg.com

The most flexible way to create a blinking light is by using Blueprints and the Timeline node. This method gives you full control over timing, intensity, and repetition.

Step 1: Add a Point Light to Your Scene

First, place a light in your level.

  • Open your Unreal Engine project.
  • In the Modes panel (top-left), go to the Place tab.
  • Search for “Point Light” and drag it into your scene.
  • Position it where you want the blinking effect—like a ceiling fixture or warning beacon.

Once placed, select the light and look at its details in the Details panel. You’ll see properties like Intensity, Light Color, and Attenuation Radius. We’ll modify these later.

Step 2: Create a Blueprint for the Light

Instead of editing the light directly, we’ll use a Blueprint to control it.

  • Right-click in the Content Browser.
  • Choose Blueprint Class.
  • Select Actor as the parent class.
  • Name it “BP_BlinkingLight” and double-click to open it.

Now, inside the Blueprint editor, we’ll add the light as a component.

  • Click Add Component and search for “Point Light”.
  • Name it “BlinkingLight”.
  • With the component selected, go to the Details panel and check Visible and Cast Shadow if needed.

Step 3: Add a Timeline Node

The Timeline node lets us animate values over time—perfect for blinking.

  • In the Event Graph, right-click and search for “Timeline”.
  • Add a Timeline node.
  • Double-click the Timeline to open its editor.

In the Timeline editor:

  • Click Add Float Track and name it “IntensityTrack”.
  • Set the length to 1.0 second (this will be one blink cycle).
  • Add two keyframes:
    • At time 0.0, set value to 0.0 (light off).
    • At time 0.5, set value to 1.0 (light on).
    • At time 1.0, set value back to 0.0 (light off).

This creates a smooth blink: off → on → off in one second.

Step 4: Connect the Timeline to Light Intensity

Now, link the Timeline output to the light’s intensity.

  • Close the Timeline editor.
  • Drag from the “IntensityTrack” output pin.
  • Search for “Set Intensity” and connect it to the BlinkingLight component.
  • Right-click the “Intensity” input and choose Promote to Variable.
  • Name it “BaseIntensity” and set its default value (e.g., 5000 lumens).

Now, multiply the Timeline value by BaseIntensity:

  • Drag from the “IntensityTrack” output.
  • Search for “Multiply (Float)”.
  • Connect the BaseIntensity variable to the second input.
  • Connect the multiply output to the “Intensity” input of “Set Intensity”.

Step 5: Start the Timeline on Begin Play

We need the blink to start when the level loads.

  • Right-click in the Event Graph and add an Event BeginPlay node.
  • Drag from its execution pin and connect it to the Play input of the Timeline.

Step 6: Test Your Blinking Light

Save and compile the Blueprint, then return to your level.

  • Drag your “BP_BlinkingLight” into the scene.
  • Press Play to test.

You should see the light blink on and off every second. If it’s too fast or slow, go back to the Timeline and adjust the keyframe times.

Method 2: Blinking Light Using Material Parameters

Sometimes, you want a surface—like a screen or sign—to blink. For that, we use materials with emissive properties.

Step 1: Create or Edit a Material

  • In the Content Browser, right-click and choose Material.
  • Name it “M_BlinkingEmissive” and open it.

In the Material Editor:

  • Set Shading Model to Unlit (so it glows without lighting).
  • Set Blend Mode to Translucent if you want transparency.

Step 2: Add a Scalar Parameter for Emissive Intensity

  • Right-click and add a Scalar Parameter.
  • Name it “EmissiveIntensity”.
  • Set its default value to 1.0.

Connect this parameter to the Emissive Color input. You can multiply it by a color (e.g., red for a warning light).

Step 3: Animate the Parameter in a Material Instance

Materials themselves can’t animate, but Material Instances can.

  • Right-click “M_BlinkingEmissive” and choose Create Material Instance.
  • Name it “MI_BlinkingRed” and open it.
  • Check the box next to “EmissiveIntensity” to make it editable.

Now, we’ll animate this value using a Blueprint.

Step 4: Create a Blueprint to Control the Material

  • Create a new Blueprint (Actor class), name it “BP_EmissiveBlinker”.
  • Add a Static Mesh component (e.g., a plane or cube).
  • Assign “MI_BlinkingRed” to its material.

In the Event Graph:

  • Add a Timeline node.
  • Create a float track named “EmissiveBlink”.
  • Set length to 1.0 second.
  • Add keyframes: 0.0 → 0.0, 0.5 → 1.0, 1.0 → 0.0.

Now, update the material parameter:

  • Drag from the “EmissiveBlink” output.
  • Search for “Set Scalar Parameter Value”.
  • Set the parameter name to “EmissiveIntensity”.
  • Connect the Timeline value to the “Value” input.
  • Connect the Static Mesh component to the “Target” input.

Finally, start the Timeline on Begin Play.

Test in the editor—your mesh should now blink with a glowing effect.

Method 3: Simple Blink Using Timers

If you prefer a simpler approach without Timelines, use timers.

Step 1: Set Up the Blueprint

  • Create a new Blueprint (Actor).
  • Add a Point Light component.
  • Name it “BlinkingLight”.

Step 2: Use a Timer to Toggle Light

In the Event Graph:

  • Add an Event BeginPlay node.
  • Drag from it and search for “Set Timer by Function Name”.
  • Name the function “ToggleLight”.
  • Set the time to 0.5 seconds (for a blink every half-second).
  • Check “Looping”.

Now, create the “ToggleLight” function:

  • Click the + next to Functions in the My Blueprint panel.
  • Name it “ToggleLight”.
  • Add a Boolean variable called “IsOn” (default: false).

Inside the function:

  • Add a Branch node.
  • Connect “IsOn” to the condition.
  • If true, set light intensity to 0 and set “IsOn” to false.
  • If false, set intensity to 5000 and set “IsOn” to true.

This creates a basic on/off blink.

Tips for Better Blinking Lights

Use Realistic Timing

Not all blinks are equal. A warning light might blink every 0.3 seconds, while a heartbeat monitor pulses slowly. Adjust your Timeline or timer to match the mood.

Add Fade Effects

Instead of instant on/off, use curves in the Timeline for smooth fade-in and fade-out. This looks more natural.

Change Colors

Modify the light’s color over time. For example, a police light can alternate between red and blue using a Timeline with two color tracks.

Use Sound Cues

Pair your blinking light with a beep or buzz using Audio Components triggered by the same Timeline.

Troubleshooting Common Issues

Light Doesn’t Blink

  • Check if the Timeline is connected to BeginPlay.
  • Ensure the light component is properly referenced.
  • Verify the Blueprint is placed in the level.

Blink Is Too Fast or Slow

  • Adjust the Timeline length or timer interval.
  • Use decimal values (e.g., 0.25 seconds) for faster blinks.

Performance Issues

  • Avoid using Event Tick for blinking—it runs every frame.
  • Use Timelines or timers instead for better performance.

Light Doesn’t Show in Game

  • Check if the light is inside a mesh or blocked by geometry.
  • Increase the Attenuation Radius.
  • Ensure the light is not set to “Stationary” if you’re changing its properties at runtime.

Advanced: Creating a Strobe Light Effect

For a dramatic strobe (like in a horror game), combine rapid blinking with sound and camera shake.

  • Use a Timeline with very short intervals (0.1 seconds).
  • Add a random delay between blinks for unpredictability.
  • Trigger a Camera Shake Blueprint on each blink.
  • Play a sharp sound cue (e.g., a spark or zap).

This creates an intense, immersive effect.

Conclusion: Master the Art of Blinking Lights

You now know how to make a blinking light in Unreal Engine using three powerful methods: Blueprints with Timelines, material animations, and timers. Each approach has its strengths—Timelines offer smooth control, materials work great for surfaces, and timers are simple and effective.

Blinking lights are more than just eye candy. They guide players, signal danger, and bring your world to life. With the skills from this guide, you can create everything from subtle ambient pulses to dramatic emergency strobes.

Remember to test your lights in different environments and optimize for performance. And don’t be afraid to experiment—mix colors, sounds, and timing to create unique effects.

Now go light up your game!