Real-Time Caustics for Unreal Engine

Bring physically-inspired caustics to Unreal Engine in real time - no Path Tracer, no complex setup, and no special UE branch required.

Video: Soon Tutorial: Soon Documentation

PRISMIX Caustics creates dynamic light patterns from glass, lenses, and other transparent objects using hardware ray tracing.

Made for cinematic artists, product visualization, archviz, and real-time rendering.

Free to download and use.

✨ Why PRISMIX Caustics?

• No Path Tracer required - works in normal real-time / UE rendering

• Easy to use with many exposed settings

• Control caustic intensity, color, softness, and more per each object / light

• Dynamic caustics that react to scene changes

• Colored caustics based on material color and spectral dispersion

• Any types and amounts of lights supported

• Supports both Translucent and Masked materials

• Roughness support for softer, more natural caustics

• Projected & Layered caustic modes

• Designed to stay lightweight and practical for real-time use

🎬 Made for Artists

Get the kind of refractive lighting normally associated with offline rendering, directly inside Unreal Engine.

Great for:

• Glass bottles and glasses

• Lenses and optical objects

• Liquids and containers

• Product visualization

• Cinematics

• Architectural visualization

• Look development

• Creative lighting

Move your objects, change your lights, change your materials - the caustics update automatically.

⚡ How It Works

PRISMIX traces photons through refractive geometry using hardware ray tracing, then reconstructs the light on surfaces as a real-time caustic effect.

It includes physically-inspired effects such as:

• Refraction

• Fresnel reflection

• Total internal reflection

• Absorption

• Spectral dispersion

• Roughness

Hardware Ray Tracing / DXR is required.

🔧 Projection Modes

• Projected: Sharp caustics on a single receiver plane. Best for the highest quality and simplest setups.

• Layered: Multiple depth layers allow caustics to appear across different depths inside the volume.

🚀 Performance

PRISMIX uses GPU ray tracing and compute shaders for tracing, accumulation, filtering, and reconstruction.

Performance depends on your GPU, photon count, resolution, depth layers, lights, and scene complexity.

It is designed primarily for real-time and cinematic workflows.

📋 Requirements

• Unreal Engine 5.8

• Windows or Linux

• Hardware Ray Tracing / DXR-capable GPU

⚠️ Known Limitations

PRISMIX is still a Beta plugin.

• Skeletal meshes are not currently supported

• Nanite may require a fallback mesh

• Masked materials are approximated as fully refractive

• Translucent surfaces currently do not receive caustics

• Each caustic volume uses one receiver orientation

• You can have only 1 volume per level

• Works best with planes / simple surfaces on which caustics are cast

🧪 Beta Notice

This is my first C++ rendering plugin, built for a technically demanding part of Unreal Engine.

It is working and usable, but bugs, crashes, visual issues, or unexpected behavior may still happen.

Please treat PRISMIX Caustics as a Beta experimental rendering tool, not as a replacement for mature Unreal rendering features such as Lumen or RTX Translucency.

There may be future updates, but they are not guaranteed.

I made PRISMIX because I wanted an easy way to create caustics in Unreal - and I wanted to give other artists the same option.

Whether you want to reproduce an offline-rendered look or create something completely new, I hope it helps.

If you find a bug, have a question, or have an idea, please leave a comment here or under the showcase video.

I'll do my best to help. Let's make it better together. ❤️