The [ReflectionProbe] is used to create high-quality reflections at a low performance cost (when [member update_mode] is [constant UPDATE_ONCE]). [ReflectionProbe]s can be blended together and with the rest of the scene smoothly. [ReflectionProbe]s can also be combined with [VoxelGI], SDFGI ([member Environment.sdfgi_enabled]) and screen-space reflections ([member Environment.ssr_enabled]) to get more accurate reflections in specific areas. [ReflectionProbe]s render all objects within their [member cull_mask], so updating them can be quite expensive. It is best to update them once with the important static objects and then leave them as-is.
[b]Note:[/b] Unlike [VoxelGI] and SDFGI, [ReflectionProbe]s only source their environment from a [WorldEnvironment] node. If you specify an [Environment] resource within a [Camera3D] node, it will be ignored by the [ReflectionProbe]. This can lead to incorrect lighting within the [ReflectionProbe].
[b]Note:[/b] Reflection probes are only supported in the Forward+ and Mobile rendering methods, not Compatibility. When using the Mobile rendering method, only 8 reflection probes can be displayed on each mesh resource. Attempting to display more than 8 reflection probes on a single mesh resource will result in reflection probes flickering in and out as the camera moves.
[b]Note:[/b] When using the Mobile rendering method, reflection probes will only correctly affect meshes whose visibility AABB intersects with the reflection probe's AABB. If using a shader to deform the mesh in a way that makes it go outside its AABB, [member GeometryInstance3D.extra_cull_margin] must be increased on the mesh. Otherwise, the reflection probe may not be visible on the mesh.
The custom ambient color to use within the [ReflectionProbe]'s box defined by its [member size]. Only effective if [member ambient_mode] is [constant AMBIENT_COLOR].
The custom ambient color energy to use within the [ReflectionProbe]'s box defined by its [member size]. Only effective if [member ambient_mode] is [constant AMBIENT_COLOR].
The ambient color to use within the [ReflectionProbe]'s box defined by its [member size]. The ambient color will smoothly blend with other [ReflectionProbe]s and the rest of the scene (outside the [ReflectionProbe]'s box defined by its [member size]).
If [code]true[/code], enables box projection. This makes reflections look more correct in rectangle-shaped rooms by offsetting the reflection center depending on the camera's location.
Sets the cull mask which determines what objects are drawn by this probe. Every [VisualInstance3D] with a layer included in this cull mask will be rendered by the probe. To improve performance, it is best to only include large objects which are likely to take up a lot of space in the reflection.
If [code]true[/code], computes shadows in the reflection probe. This makes the reflection probe slower to render; you may want to disable this if using the [constant UPDATE_ALWAYS] [member update_mode].
The maximum distance away from the [ReflectionProbe] an object can be before it is culled. Decrease this to improve performance, especially when using the [constant UPDATE_ALWAYS] [member update_mode].
[b]Note:[/b] The maximum reflection distance is always at least equal to the probe's extents. This means that decreasing [member max_distance] will not always cull objects from reflections, especially if the reflection probe's box defined by its [member size] is already large.
The automatic LOD bias to use for meshes rendered within the [ReflectionProbe] (this is analog to [member Viewport.mesh_lod_threshold]). Higher values will use less detailed versions of meshes that have LOD variations generated. If set to [code]0.0[/code], automatic LOD is disabled. Increase [member mesh_lod_threshold] to improve performance at the cost of geometry detail, especially when using the [constant UPDATE_ALWAYS] [member update_mode].
[b]Note:[/b] [member mesh_lod_threshold] does not affect [GeometryInstance3D] visibility ranges (also known as "manual" LOD or hierarchical LOD).
Sets the origin offset to be used when this [ReflectionProbe] is in [member box_projection] mode. This can be set to a non-zero value to ensure a reflection fits a rectangle-shaped room, while reducing the number of objects that "get in the way" of the reflection.
The size of the reflection probe. The larger the size, the more space covered by the probe, which will lower the perceived resolution. It is best to keep the size only as large as you need it.
[b]Note:[/b] To better fit areas that are not aligned to the grid, you can rotate the [ReflectionProbe] node.
Update the probe once on the next frame (recommended for most objects). The corresponding radiance map will be generated over the following six frames. This takes more time to update than [constant UPDATE_ALWAYS], but it has a lower performance cost and can result in higher-quality reflections. The ReflectionProbe is updated when its transform changes, but not when nearby geometry changes. You can force a [ReflectionProbe] update by moving the [ReflectionProbe] slightly in any direction.
Update the probe every frame. This provides better results for fast-moving dynamic objects (such as cars). However, it has a significant performance cost. Due to the cost, it's recommended to only use one ReflectionProbe with [constant UPDATE_ALWAYS] at most per scene. For all other use cases, use [constant UPDATE_ONCE].
Apply custom ambient lighting inside the [ReflectionProbe]'s box defined by its [member size]. See [member ambient_color] and [member ambient_color_energy].
