Method

RT Mirror Reflection is the fastest raytracing reflections node with only a single, sharp ray traced bounce supported.
This can be used to simulate mirrors, reflections and specular on any raytracing enabled specular material/surface. Rough reflections can be approximated using the blurring properties.

As it only uses one bounce, secondary bounces such as a mirror reflecting another mirror will not work. This node is best-used for scenes that need to run more optimally at higher framerates.

A scene using RT Mirror Reflections
A scene using RT Mirror Reflections

Sample

RT Mirror Reflection node

RT_MirrorReflection.dfx

This sample uses light-baked assets in the scene.

RT Mirror Reflection example nodegraph

Attributes

Name Description
Path Tracer Shader Import a shader source code file as a resource.
Denoising / Refinement Toggles on and off denoising / refinement.
Ray Bias Sets the bias of the rays.
Sample clamp Clamps the reflectiveness of the rays.
Run at Reduced Resolution (Faster) Halves the rays used in ray tracing, dramatically increasing performance in some scenes.

Blur

Name Description
Blur Reflections When enabled, Notch will attempt to generate approximate reflections using a post blur pass on the mirror reflections.
Blur Quality Increases the number of samples taken for the post blur.
Blur Scale Adjusts the scale of the blur. Best used to correct the blur pass for scene scale.

Environment Map

Name Description
Environment Brightness The brightness of the environment map.
Environment Specular Toggles on and off environment specular.
Environment Filtering Toggles on and off environment filtering.

Inputs

Name Description Typical Node Input
Object Nodes Only reflect particular objects in the scene. Great for making vampires. 3D Object
Fast-Path Specular Sky Lights Sky lights linked to this input will have their specular component traced by the RT Mirror Reflection node as a mirror reflection ray, instead of in the Sky Light’s direct illumination pass. This allows the result to be post-blurred with the RT Mirror Reflection’s blur pass, and is also faster as less rays need to be cast. Sky Lights

Outputs

All nodes connected to this node are treated as if flowing to the parent node, and inherits any transformation changes along the chain.