Class OccluderInstance3D
- Namespace
- Godot
- Assembly
- GodotSharp.dll
Occlusion culling can improve rendering performance in closed/semi-open areas by hiding geometry that is occluded by other objects.
The occlusion culling system is mostly static. OccluderInstance3Ds can be moved or hidden at run-time, but doing so will trigger a background recomputation that can take several frames. It is recommended to only move OccluderInstance3Ds sporadically (e.g. for procedural generation purposes), rather than doing so every frame.
The occlusion culling system works by rendering the occluders on the CPU in parallel using Embree, drawing the result to a low-resolution buffer then using this to cull 3D nodes individually. In the 3D editor, you can preview the occlusion culling buffer by choosing Perspective > Debug Advanced... > Occlusion Culling Buffer in the top-left corner of the 3D viewport. The occlusion culling buffer quality can be adjusted in the Project Settings.
Baking: Select an OccluderInstance3D node, then use the Bake Occluders button at the top of the 3D editor. Only opaque materials will be taken into account; transparent materials (alpha-blended or alpha-tested) will be ignored by the occluder generation.
Note: Occlusion culling is only effective if ProjectSettings.rendering/occlusion_culling/use_occlusion_culling is true. Enabling occlusion culling has a cost on the CPU. Only enable occlusion culling if you actually plan to use it. Large open scenes with few or no objects blocking the view will generally not benefit much from occlusion culling. Large open scenes generally benefit more from mesh LOD and visibility ranges (VisibilityRangeBegin and VisibilityRangeEnd) compared to occlusion culling.
Note: Due to memory constraints, occlusion culling is not supported by default in Web export templates. It can be enabled by compiling custom Web export templates with module_raycast_enabled=yes.
public class OccluderInstance3D : Node3D, IDisposable- Inheritance
-
OccluderInstance3D
- Implements
- Inherited Members
Constructors
OccluderInstance3D()
public OccluderInstance3D()Properties
BakeMask
The visual layers to account for when baking for occluders. Only MeshInstance3Ds whose Layers match with this BakeMask will be included in the generated occluder mesh. By default, all objects with opaque materials are taken into account for the occluder baking.
To improve performance and avoid artifacts, it is recommended to exclude dynamic objects, small objects and fixtures from the baking process by moving them to a separate visual layer and excluding this layer in BakeMask.
public uint BakeMask { get; set; }Property Value
BakeSimplificationDistance
The simplification distance to use for simplifying the generated occluder polygon (in 3D units). Higher values result in a less detailed occluder mesh, which improves performance but reduces culling accuracy.
The occluder geometry is rendered on the CPU, so it is important to keep its geometry as simple as possible. Since the buffer is rendered at a low resolution, less detailed occluder meshes generally still work well. The default value is fairly aggressive, so you may have to decrease it if you run into false negatives (objects being occluded even though they are visible by the camera). A value of 0.01 will act conservatively, and will keep geometry perceptually unaffected in the occlusion culling buffer. Depending on the scene, a value of 0.01 may still simplify the mesh noticeably compared to disabling simplification entirely.
Setting this to 0.0 disables simplification entirely, but vertices in the exact same position will still be merged. The mesh will also be re-indexed to reduce both the number of vertices and indices.
Note: This uses the meshoptimizer library under the hood, similar to LOD generation.
public float BakeSimplificationDistance { get; set; }Property Value
Occluder
The occluder resource for this OccluderInstance3D. You can generate an occluder resource by selecting an OccluderInstance3D node then using the Bake Occluders button at the top of the editor.
You can also draw your own 2D occluder polygon by adding a new PolygonOccluder3D resource to the Occluder property in the Inspector.
Alternatively, you can select a primitive occluder to use: QuadOccluder3D, BoxOccluder3D or SphereOccluder3D.
public Occluder3D Occluder { get; set; }Property Value
Methods
GetBakeMaskValue(int)
Returns whether or not the specified layer of the BakeMask is enabled, given a layerNumber between 1 and 32.
public bool GetBakeMaskValue(int layerNumber)Parameters
layerNumberint
Returns
HasGodotClassMethod(in godot_string_name)
Check if the type contains a method with the given name. This method is used by Godot to check if a method exists before invoking it. Do not call or override this method.
protected override bool HasGodotClassMethod(in godot_string_name method)Parameters
methodgodot_string_nameName of the method to check for.
Returns
HasGodotClassSignal(in godot_string_name)
Check if the type contains a signal with the given name. This method is used by Godot to check if a signal exists before raising it. Do not call or override this method.
protected override bool HasGodotClassSignal(in godot_string_name signal)Parameters
signalgodot_string_nameName of the signal to check for.
Returns
InvokeGodotClassMethod(in godot_string_name, NativeVariantPtrArgs, out godot_variant)
Invokes the method with the given name, using the given arguments. This method is used by Godot to invoke methods from the engine side. Do not call or override this method.
protected override bool InvokeGodotClassMethod(in godot_string_name method, NativeVariantPtrArgs args, out godot_variant ret)Parameters
methodgodot_string_nameName of the method to invoke.
argsNativeVariantPtrArgsArguments to use with the invoked method.
retgodot_variantValue returned by the invoked method.
Returns
SetBakeMaskValue(int, bool)
Based on value, enables or disables the specified layer in the BakeMask, given a layerNumber between 1 and 32.
public void SetBakeMaskValue(int layerNumber, bool value)