Reflection probes

Introduction

Spatial Material, objects can show reflected or diffuse light. Reflection probes are used as a source of reflected and ambient light for objects inside their area of influence. blur. This is used to simulate roughness in materials, as well as ambient lighting. While these probes are an efficient way of storing reflections, they have a few shortcomings:

• They are efficient to render, but expensive to compute. This leads to a default behavior where they only capture on scene load.
• They work best for rectangular shaped rooms or places, otherwise the reflections shown are not as faithful (especially when roughness is 0).

  Setting up

  Create a ReflectionProbe node and wrap it around the area where you want to have reflections: This should result in immediate local reflections. If you are using a Sky texture, reflections are by default blended with it. “Box Correct” property. This setting changes the reflection from an infinite skybox to reflecting a box the size of the probe: Adjusting the box walls may help improve the reflection a bit, but it will always look best in box shaped rooms. The probe captures the surrounding from the center of the gizmo. If, for some reason, the room shape or contents occlude the center, it can be displaced to an empty place by moving the handles in the center: Enable Shadow setting: Cull Mask setting:

  Interior vs exterior

  Interior property be enabled. This stops the probe from rendering the sky and also allows custom ambient lighting settings. Interior, custom constant ambient lighting can be specified per probe. Just choose a color and an energy. Ambient Contribution property (0.0 means pure ambient color, while 1.0 means pure diffuse capture).

  Blending

  Multiple reflection probes can be used, and Godot will blend them where they overlap using a smart algorithm: As you can see, this blending is never perfect (after all, these are box reflections, not real reflections), but these artifacts are only visible when using perfectly mirrored reflections. Normally, scenes have normal mapping and varying levels of roughness, which can hide this. Alternatively, Reflection Probes work well blended together with Screen Space Reflections to solve these problems. Combining them makes local reflections appear more faithful, while probes are only used as a fallback when no screen-space information is found: exterior (so it will get sky reflections) while on the inside, it can be interior.

  Reflection atlas

  In the current renderer implementation, all probes are the same size and are fit into a Reflection Atlas. The size and amount of probes can be customized in Project Settings -> Quality -> Reflections The default setting of Atlas Subdiv: 8 will allow up to 16 reflection probes in a scene. This value needs to be increased if you need more reflection probes.