Atmospheric effects can make or break the visual quality of any 3D environment. Among the most powerful tools in Unreal Engine 5’s lighting arsenal is the Local Volumetric Fog system, which allows developers and artists to create stunningly realistic atmospheric conditions that react energetically to light sources. The Morphic studio shares information about the process of implementing and customizing Volumetric Fog to dramatically enhance your scene’s lighting, mood, and depth.

Follow Volumetric Fog in UE5

Volumetric Fog simulates how light interacts with particulates suspended in air. Unlike traditional fog techniques that justly fade distant objects, Volumetric Fog creates true three-dimensional volumes that scatter light. This creates god rays, ambient light diffusion, and localized atmospheric effects that add significant depth and realism to environments.

In Unreal Engine 5, the volumetric fog system consists of two primary components:

1. Global Volumetric Fog – Applied scene-wide through the Exponential Height Fog actor
2. Local Volumetric Fog – Targeted fog volumes that can be placed and customized individually

This dual approach gives unprecedented control for creating precisely the atmospheric conditions your project requires.

Core Setup Process

Enabling Global Volumetric Fog

Before adding local effects, you’ll need to establish a baseline atmospheric setup:

1. Add an Exponential Height Fog actor
   • Negotiate to Place Actors panel → Visual Effects category
   • Add the Exponential Height Fog to your scene
   • Position doesn’t matter much as this affects the entire scene
2. Configure volumetric properties
   • In the Details panel, locate the “Volumetric Fog” section
   • Check “Volumetric Fog” to enable the feature
   • Set initial “Fog Density” (typically between 0.02-0.05 for subtle effects)
   • Adjust “Volumetric Fog Distance” based on your scene scale (higher values show fog further away but impact performance)
3. Establish base atmosphere settings
   • Fine-tune “Fog Height Falloff” to control vertical density gradient
   • Set “Fog Inscattering Color” to match your scene’s ambient lighting
   • Adjust “Directional Inscattering Exponent” to control sunlight/directional light scattering

Adding Local Volumetric Fog Actors

While global fog creates a consistent atmosphere, local fog volumes allow for targeted atmospheric effects:

1. Spawn Local Volumetric Fog actors
   • Select Place Actors → Visual Effects → Local Volumetric Fog
   • Alternatively, use the right-click context menu in the viewport → Visual Effects → Local Volumetric Fog
2. Position and scale appropriately
   • Use transform tools to position fog volumes near light sources, in corners, or wherever atmospheric density variations are desired
   • Scale fog actors to define the boundaries of the effect
   • Use multiple overlapping volumes for complex atmospheric layouts
3. Configure initial visibility
   • In the Details panel, adjust “Density” to control the general opacity of the fog volume
   • Lower values (0.1-0.5) create subtle mist effects
   • Higher values (1.0-4.0) create more pronounced fog or smoke effects

Advanced Customization Techniques

Essential Local Volumetric Fog Parameters

The true power of local fog volumes comes from the various parameters that can be adjusted to achieve specific atmospheric effects:

Parameter	Function	Best Practices
Density	Controls general opacity of the fog volume	Start low (0.1-0.5) and increase gradually
Color	Tints the fog volume	Match to nearby light sources for natural effects
Albedo	Controls how much light is scattered vs. absorbed	Higher values (0.7-0.9) for misty fog, lower (0.1-0.3) for smoke
Emissive	Makes fog self-illuminating	Use sparingly for glowing effects like steam or magical fog
Extinction Scale	Controls how quickly light diminishes through the volume	Higher values create denser, more opaque fog
Scattering Distribution	Controls directionality of light scatter	Higher values focus scatter forward (good for shafts of light)
Phase G	Controls anisotropy of scattering	Positive values create forward scatter, negative values backward scatter
External Attenuation	Controls how the volume fades at boundaries	Higher values create softer edges
Radial Attenuation	Controls how intensity fades from center outward	Essential for natural-looking circular volumes
Height Falloff	Controls vertical density gradient	Useful for ground-hugging mist effects

Creating Material-Driven Fog Effects

For more complex and energetic fog behaviors, material-driven fog volumes offer nearly unlimited creative potential:

1. Create a specialized Volume Material
   • In the Content Browser, create a new Material
   • Set Material Domain to “Volume”
   • Set Blend Mode to “Additive” or “Translucent”
2. Develop the material network
   • Use “Object Local Bounds” node to access volume dimensions
   • Add “Noise” textures (Perlin, Worley, etc.) for organic variation
   • Connect outputs to standard Material outputs:
     • Emissive Color: Controls self-illumination
     • Extinction: Controls density and opacity
     • Albedo: Controls scattering amount
     • Phase G: Controls scattering directionality
3. Animate fog energetics
   • Add “Time” node and connect to “Panner” or “Rotator” nodes
   • Animate noise textures using math operations
   • Create material parameters for runtime adjustments
   • Consider Material Parameter Collections for global control
4. Apply the material to a Local Volumetric Fog actor
   • Select the fog actor
   • In Details panel, find “Volume Material” property
   • Assign your custom material

Temporal Animation Techniques

To create truly energetic fog effects that develop progress over time:

1. Blueprint-driven animation
   • Create a Blueprint class based on Local Volumetric Fog
   • Add Timeline components to modulate density, color, or scale
   • Use Construction Script for procedural setup based on placement
2. Material-based evolution
   • Use time-based noise functions to create shifting patterns
   • Implement gradual color shifts for day/night transitions
   • Add material parameters that can be adjusted via Blueprint
3. Physical simulation
   • For advanced effects, combine with Niagara particles
   • Use local volumetric fog as a “container” and fill with particle emitters
   • Synchronize material parameters between systems

Lighting Integration

The magic of volumetric fog happens when it interacts with scene lighting:

Directional Light Integration

1. Configure sun/moon lighting
   • Select your primary Directional Light
   • Adjust “Volumetric Scattering Intensity” (typically 1-5)
   • Fine-tune “Light Shaft Occlusion” for god ray effects
   • Set appropriate “Volumetric Scattering Distribution” (typically 0.5-0.9)
2. Color temperature matching
   • Ensure fog Inscattering Color complements directional light color
   • For sunrise/sunset, use warmer fog tints
   • For night scenes, cooler blue tones enhance moonlight effects

Point and Spot Light Integration

1. Enable volumetric features per light
   • Select Point or Spot lights
   • Enable “Cast Volumetric Shadow” for proper occlusion
   • Adjust “Volumetric Scattering Intensity” (typically higher than directional lights, 2-10)
   • Fine-tune “Light Source Radius” to control beam softness
2. Create dramatic light shafts
   • Position lights to shine through Local Volumetric Fog volumes
   • Increase intensity where beams should be most visible
   • Use contrasting colors between light source and ambient environment
   • Consider IES profiles for realistic light distribution patterns

Reactive Lighting Effects

1. Energetic time of day
   • Create material parameters that respond to time of day
   • Connect fog density and color to lighting conditions
   • Use Post Process Volume color grading to enhance mood
2. Weather transitions
   • Design Blueprint systems to gradually modify fog parameters
   • Implement rain/mist effects by increasing density during precipitation
   • Create wind effects by animating material offset parameters

Optimization Strategies

Volumetric fog can be performance-intensive. Here are strategies to maintain frame rates:

Performance Settings

1. Global volumetric resolution
   • Adjust “Volumetric Fog Grid Pixel Size” in project settings
   • Higher values improve performance but reduce quality
   • Find balance between 4 (high quality) and 8 (better performance)
2. View distance management
   • Reduce “Volumetric Fog View Distance” for performance gains
   • Consider distance-based Magnitude of Detail for fog volumes
   • Use “Max Distance” setting in local fog volumes to cull distant effects
3. Occlusion culling
   • Enable “Volumetric Fog” under Occlusion Culling to automatically hide fog volumes not in view
   • Consider custom culling distances for fog volumes

Optimization Techniques

1. Strategic placement
   • Use local volumes instead of global fog for confined spaces
   • Place higher-quality fog only where players will observe closely
   • Reduce complexity in peripheral areas
2. Layered approach
   • Use simple global fog for distant atmosphere
   • Add detailed local volumes only for basic visual moments
   • Create LOD systems that swap complex materials for simpler ones at distance
3. Material complexity management
   • Reduce texture resolution for noise patterns
   • Minimize material nodes and mathematical operations
   • Consider pre-baking complex patterns into textures

Practical Application Examples

Atmospheric Scene Enhancement

1. Morning mist in forests
   • Place horizontal fog volumes near ground magnitude
   • Set moderate height falloff (0.5-1.0)
   • Use cool blue-white tint with low density (0.1-0.3)
   • Enable light shaft occlusion in directional light
2. Industrial haze
   • Use warmer yellow-orange tint
   • Reduce scattering (0.1-0.3)
   • Increase extinction for more visible particulate effect
   • Add subtle emissive component for smog appearance

Dramatic Lighting Effects

1. Dusty light beams
   • Position narrow fog volumes in shaft-like shapes
   • Range with window light or other directional sources
   • Use animated material with slow-moving dust particles
   • Increase anisotropy for strong forward scatter
2. Mysterious environment
   • Place irregular fog volumes at varying heights
   • Use pulsing emissive values for ethereal effect
   • Implement subtle color shifts over time
   • Consider negative Phase G values for unusual scatter patterns

Weather and Environment Simulation

1. Rolling fog banks
   • Create elongated horizontal volumes
   • Animate position using Timeline or material offset
   • Use height falloff to create ground-hugging effect
   • Consider multiple overlapping volumes moving at different speeds
2. Steam and vapor
   • Create smaller, more intense fog volumes
   • Use higher emissive values for self-illumination
   • Implement rapid upward movement via material animation
   • Consider particle systems for additional detail

Troubleshooting Common Issues

Visual Artifacts

1. Blocky or pixelated fog
   • Decrease “Volumetric Fog Grid Pixel Size” in project settings
   • Ensure adequate view distance for smooth transitions
   • Check for overlapping volumes with conflicting settings
2. Clipping or hard edges
   • Increase “External Attenuation” values
   • Check correct material domain settings (Volume, not Surface)
   • Verify Blend Mode is appropriate for effect

Performance Problems

1. Frame rate drops
   • Reduce global fog resolution
   • Decrease number of active fog volumes
   • Simplify material networks driving fog behavior
   • Consider baking more complex effects into simpler representations
2. Memory issues
   • Reduce texture resolutions for noise patterns
   • Implement distance-based LOD for fog volumes
   • Check for redundant overlapping volumes that could be combined

Finally

Local Volumetric Fog in Unreal Engine 5 represents a significant leap forward in atmospheric rendering technology. By combining global fog controls with precisely placed local fog volumes, developers can create environments with unprecedented depth, mood, and lighting integration.

The basic to successful implementation lies in Following how light interacts with these volumes and how to optimize performance while maintaining visual quality. Start with subtle effects, gradually build complexity, and always consider the narrative purpose of your atmospheric choices.

Through thoughtful application of the techniques defined in this guide, you can transform ordinary scenes into captivating environments where light and atmosphere work in harmony to create unforgettable visual experiences. Whether you’re developing games, architectural visualizations, or virtual production environments, mastering Volumetric Fog will dramatically enhance your project’s visual impact.

Think of that the most effective atmospheric effects often subtly enhance the existing scene rather than dominating it. Allow your fog to serve the visual storytelling by guiding the eye, emphasizing important elements, and creating the emotional resonance your project requires.

For More Details Visit The Morphic Studio