unreal.MeshNaniteSettings

class unreal.MeshNaniteSettings(enabled: bool = False, preserve_area: bool = False, explicit_tangents: bool = False, lerp_u_vs: bool = False, position_precision: int = 0, normal_precision: int = 0, tangent_precision: int = 0, keep_percent_triangles: float = 0.0, trim_relative_error: float = 0.0, fallback_target: NaniteFallbackTarget = Ellipsis, fallback_percent_triangles: float = 0.0, fallback_relative_error: float = 0.0, max_edge_length_factor: float = 0.0, displacement_uv_channel: int = 0)

Bases: StructBase

Settings applied when building Nanite data.

C++ Source:

• Module: Engine

• File: EngineTypes.h

Editor Properties: (see get_editor_property/set_editor_property)

• displacement_maps (Array[MeshDisplacementMap]): [Read-Write]

• displacement_uv_channel (int32): [Read-Write] UV channel used to sample displacement maps

• enabled (bool): [Read-Write] If true, Nanite data will be generated.

• explicit_tangents (bool): [Read-Write] Whether to store explicit tangents instead of using the implicitly derived ones.

• fallback_percent_triangles (float): [Read-Write] Percentage of triangles to keep from source mesh for fallback. 1.0 = no reduction, 0.0 = no triangles.

• fallback_relative_error (float): [Read-Write] Reduce until at least this amount of error is reached relative to size of the mesh

• fallback_target (NaniteFallbackTarget): [Read-Write] Which heuristic to use when generating the fallback mesh.

• keep_percent_triangles (float): [Read-Write] Percentage of triangles to keep from source mesh. 1.0 = no reduction, 0.0 = no triangles.

• lerp_u_vs (bool): [Read-Write] Whether to interpolate UVs when simplifying. Should be enabled whenever possible. For real UV coordinates this allows calculating the lowest error optimal UVs for new vertices when simplifying, assuming the UVs are used as normal texture coordinates and will interpolate across the face of the triangles.

  Disable if data stored in UVs isn’t valid to interpolate, for example if indexes are stored in UVs. Lerping an index doesn’t make sense and would break the shader trying to use it. Note: If disabled, error from UVs is no longer accounted for when Nanite selects the LOD to render because error due to arbitary vertex attributes that aren’t interpolatable can’t be generally reasoned about.

• max_edge_length_factor (float): [Read-Write] Controls the maximum distance allowed between each vertex of the mesh on screen. Can be used to prevent oversimplification of meshes that are intended to be deformed (e.g. animation using World Position Offset, Spline Mesh Component, etc.). Should be left at default of 0 unless explicitly needed to fix oversimplification issues.

• normal_precision (int32): [Read-Write] Normal Precision in bits. -1 is auto.

• position_precision (int32): [Read-Write] Position Precision. Step size is 2^(-PositionPrecision) cm. MIN_int32 is auto.

• preserve_area (bool): [Read-Write] Whether to try and maintain the same surface area at all distances. Useful for foliage that thins out otherwise.

• tangent_precision (int32): [Read-Write] Tangent Precision in bits. -1 is auto.

• target_minimum_residency_in_kb (uint32): [Read-Write] How much of the resource should always be resident (In KB). Approximate due to paging. 0: Minimum size (single page). MAX_uint32: Entire mesh.

• trim_relative_error (float): [Read-Write] Reduce until at least this amount of error is reached relative to size of the mesh

property displacement_uv_channel: int

[Read-Write] UV channel used to sample displacement maps

Type:

(int32)

property enabled: bool

[Read-Write] If true, Nanite data will be generated.

Type:

(bool)

property explicit_tangents: bool

[Read-Write] Whether to store explicit tangents instead of using the implicitly derived ones.

Type:

(bool)

property fallback_percent_triangles: float

[Read-Write] Percentage of triangles to keep from source mesh for fallback. 1.0 = no reduction, 0.0 = no triangles.

Type:

(float)

property fallback_relative_error: float

[Read-Write] Reduce until at least this amount of error is reached relative to size of the mesh

Type:

(float)

property fallback_target: NaniteFallbackTarget

[Read-Write] Which heuristic to use when generating the fallback mesh.

Type:

(NaniteFallbackTarget)

property keep_percent_triangles: float

[Read-Write] Percentage of triangles to keep from source mesh. 1.0 = no reduction, 0.0 = no triangles.

Type:

(float)

property lerp_u_vs: bool

[Read-Write] Whether to interpolate UVs when simplifying. Should be enabled whenever possible. For real UV coordinates this allows calculating the lowest error optimal UVs for new vertices when simplifying, assuming the UVs are used as normal texture coordinates and will interpolate across the face of the triangles.

Disable if data stored in UVs isn’t valid to interpolate, for example if indexes are stored in UVs. Lerping an index doesn’t make sense and would break the shader trying to use it. Note: If disabled, error from UVs is no longer accounted for when Nanite selects the LOD to render because error due to arbitary vertex attributes that aren’t interpolatable can’t be generally reasoned about.

Type:

(bool)

property max_edge_length_factor: float

[Read-Write] Controls the maximum distance allowed between each vertex of the mesh on screen. Can be used to prevent oversimplification of meshes that are intended to be deformed (e.g. animation using World Position Offset, Spline Mesh Component, etc.). Should be left at default of 0 unless explicitly needed to fix oversimplification issues.

Type:

(float)

property normal_precision: int

[Read-Write] Normal Precision in bits. -1 is auto.

Type:

(int32)

property position_precision: int

[Read-Write] Position Precision. Step size is 2^(-PositionPrecision) cm. MIN_int32 is auto.

Type:

(int32)

property preserve_area: bool

[Read-Write] Whether to try and maintain the same surface area at all distances. Useful for foliage that thins out otherwise.

Type:

(bool)

property tangent_precision: int

[Read-Write] Tangent Precision in bits. -1 is auto.

Type:

(int32)

property trim_relative_error: float

[Read-Write] Reduce until at least this amount of error is reached relative to size of the mesh

Type:

(float)