UsdGeometry
Overview
UsdGeometry generates geometry loaded from a USD file.
Attribute Reference
Curve attributes
base_width_factor
Float
default: 1.0
Multiplier for the radius of the base of curves
curves_subtype
Int enum
0 = “ray_facing” (default)
1 = “round”
Set the style that curve primitives are rendered in
radius_mult
Float
default: 1.0
Multiplier for the radius of points and curves
tip_width_factor
Float
default: 1.0
Multiplier for the radius of the tip of curves
Curves attributes
tessellation_rate
Int
default: 4
Number of segments to split curve spans into
Geometry attributes
reverse_normals
Bool
default: False
enable to reverse the normals in the geometry
side_type
Int enum
0 = “force two-sided” (default)
1 = “force single-sided”
2 = “use mesh sidedness”
set single sidedness of the mesh, will affect the visibility of the mesh based on normal direction
Labels attributes
label
String
default:
label used in material aov expresssions
shadow_receiver_label
String
default:
Label used to associate Geometry objects into sets. Then, using the ["shadow_exclusion_mappings"] attribute, shadows from specified geometry parts can be suppressed from casting onto specified sets.
Mesh attributes
adaptive_error
Float
default: 0.0
The maximum allowable difference in pixels for subdivison mesh adaptive tessellation (each final tessellated edge won't be longer than n pixels if adaptive error is set to n).A value of 0 disables adaptive tessellation, reverting to uniform tessellation, which sometimes is more stable in animation.Adaptive tessellation is not supported for instances.
mesh_resolution
Float
default: 2.0
The maximum resolution to tessellate a mesh. An edge on input face will be tessellated to at most n segments when "mesh resolution" is set to n. If "adaptive error" is set to 0, every edge on input face will be uniformly tessellated to "mesh resolution". Otherwise renderer will adaptively tessellate mesh based on camera information
smooth_normal
Bool
default: True
Generates smooth shading normals when rendering a PolygonMesh and the mesh doesn't provide shading normal itself
subd_type
Int enum
0 = “use mesh type” (default)
1 = “force polygon mesh”
2 = “force subdivision mesh”
PolygonMesh/SubdivisionMesh prim type to create.
"use mesh type" will use the type the Mesh prim specifies.
"force polygon mesh" will always resolve to PolygonMesh.
"force subdivision mesh" will always resolve to SubdivisionMesh.
Motion Blur attributes
curved_motion_blur_sample_count
Int
default: 10
Number of time samples generated along each curve when using curved motion blur
motion_blur_type
Int enum
-1 = “best” (default)
0 = “static”
1 = “velocity”
2 = “frame delta”
3 = “acceleration”
4 = “hermite”
Motion blur type for PolygonMesh/Points/Curves in alembic file.
"static" will treat the mesh as static.
"velocity" will blur using the supplied vertex positions and velocities.
"frame delta" will interpolate between the two supplied vertex positions.
"acceleration" will blur using the supplied vertex positions, velocities and accelerations.
"hermite" will use supplied pair of positions and pair of velocities to interpolate along a cubic Hermite curve.
"best" will use choose the method which provides the highest quality given the available data.
primitive_attribute_frame
Int enum
0 = “first motion step”
1 = “second motion step”
2 = “both motion steps” (default)
Which frame(s) do we take the primitive attributes from?
O : first motion step
1 : second motion step
2 : both motion steps
use_rotation_motion_blur
Bool
default: False
If "xform" is time varying and motion blur is turned on, this toggle can generate better rotation trail. Turning on this will disable adaptive tessellation
Ray Tracing attributes
ray_epsilon
Float
default: 0.0
When a secondary ray is fired, anything within this distance of the intersection point will be ignored. Instead, it is considered part of the current intersection's geometry. If zero, an automatically calculated epsilon will be used.
shadow_ray_epsilon
Float
default: 0.0
When a shadow ray is fired, anything within this distance of the intersection point will be ignored. If this value is less than "ray_epsilon", then it has no additional effect.
Time attributes
evaluation_frame
Float
default: 1.0
Evaluates geometry at the specified frame instead of SceneVariables frame
use_evaluation_frame
Bool
default: False
Uses "evaluation frame" instead of SceneVariables frame
USD attributes
prim_path
String
default:
The geometry Prim to load from the USD Stage
stage
String filename
default:
USD Stage to load
use_master_xform
Bool
default: False
If the prim is an instance proxy, use the xform from the master Prim during geometry creation
use_prim_xform
Bool
default: True
Include the xform from the Prim during geometry creation
use_stage_cache
Bool
default: False
Load the entire stage and use StageCache to share it among all UsdGeometry objects.
If this is false, load a stage masked to the prim path just for this UsdGeometry.
For large stages with thousands of unique assets, it is faster to enable the stage cache
User Data attributes
part_list
StringVector
default: {}
Ordered list of part names. The length of the
list should match the length of any "part" rate primitive attribute
primitive_attributes
UserData Vector
default: {}
A list of UserData scene objects specifying arbitrary primitive attributes
Visibility attributes
visible_diffuse_reflection
Bool
default: True
whether the geometry is visible in diffuse reflection
visible_diffuse_transmission
Bool
default: True
whether the geometry is visible in diffuse transmission
visible_glossy_reflection
Bool
default: True
whether the geometry is visible in glossy reflection.
visible_glossy_transmission
Bool
default: True
whether the geometry is visible in glossy transmission (refraction).
visible_in_camera
Bool
default: True
whether the geometry is visible to camera rays
visible_mirror_reflection
Bool
default: True
whether the geometry is visible in miror reflection.
visible_mirror_transmission
Bool
default: True
whether the geometry is visible in miror transmission (refraction).
visible_shadow
Bool
default: True
whether the geometry casts shadows
visible_volume
Bool
default: True
whether the geometry is visible in indirect volume rays
General attributes
contains_camera
Bool
default: False
Specifies whether the geometry contains the camera and should be used for IOR tracking. This should not be changed by the user -- they should instead attach the relevant geometry to the camera, which will then flag this geometry.
dicing_camera
SceneObject
default: None
Alternate camera that is used for adaptive tessellation. This is useful if you want adaptive tessellation to behave consistently in a sequence, regardless of what the main camera is doing
node_xform
Mat4d blurrable
default: [ [ 1, 0, 0, 0 ], [ 0, 1, 0, 0 ], [ 0, 0, 1, 0 ], [ 0, 0, 0, 1 ] ]
The 4x4 matrix describing the transformation from local space to world space.
references
Geometry Vector
default: {}
list of geometries that geometry procedural can reference during procedural generate/update stages. For example, an instancer geometry procedural can instance primitives generated by the reference geometry procedural.
shadow_exclusion_mappings
String
default:
List of mappings of the form A:B where:
A is a list of names of parts to be mapped, or asterisk to map the whole geometry
B is a list of labels corresponding to the sets corresponding to distinct values of ["shadow_receiver_label"], or asterisk to map to all such sets.
static
Bool
default: True
disable if the geometry will be updated between frames