OpenUSD Data Types

The OpenUSD API Documentation has a list of USD Basic Data Types that are used for Attribute types. Type Name are provided by the Sdf.ValueTypeNames module, which is a useful resource for reference.

In order to pass a valid value for the type for the CreateAttribute(name, type) function, it needs to be a reference to a Sdf.ValueTypeNames.TypeName object. There are three ways of getting these:

1. Using Python Objects

The current values and how to construct an object that will function as that value are in a table here for convenience, please refer to the USD Basic Data Types page for an explanation on explicit definitions. The Value Type Token column denotes how each Type Name appears in a .usda file.

Tip

Gf.Vec3d/f/h instances below can be constructed with just a (float, float, float) tuple (and Vec2d/f/h ``, ``Vec4d/f/h as well), but the explicit declaration is passed below for completeness.

Note

[] denotes a list of types. The left column of this list was generated with the method from 1) above.

Type Name	Value Type Token	Python Constructor
Asset	asset	string
AssetArray	asset[]	[string]
Bool	bool	bool
BoolArray	bool[]	[bool]
Color3d	color3d	Gf.Vec3d(float, float, float)
Color3dArray	color3d[]	[Gf.Vec3d(float, float, float)]
Color3f	color3f	Gf.Vec3f(float, float, float)
Color3fArray	color3f[]	[Gf.Vec3f(float, float, float)]
Color3h	color3h	Gf.Vec3h(float, float, float)
Color3hArray	color3h[]	[Gf.Vec3h(float, float, float)]
Color4d	color4d	Gf.Vec4d(float, float, float, float)
Color4dArray	color4d[]	[Gf.Vec4d(float, float, float, float)]
Color4f	color4f	Gf.Vec4f(float, float, float, float)
Color4fArray	color4f[]	[Gf.Vec4f(float, float, float, float)]
Color4h	color4h	Gf.Vec4h(float, float, float, float)
Color4hArray	color4h[]	[Gf.Vec4h(float, float, float, float)]
Double	double	float
Double2	double2	(float, float)
Double2Array	double2[]	[(float, float)]
Double3	double3	(float, float, float)
Double3Array	double3[]	[(float, float, float)]
Double4	double4	(float, float, float, float)
Double4Array	double4[]	[(float, float, float, float)]
DoubleArray	double[]	[float]
Float	float	float
Float2	float2	(float, float)
Float2Array	float2[]	[(float, float)]
Float3	float3	(float, float, float)
Float3Array	float3[]	[(float, float, float)]
Float4	float4	(float, float, float, float)
Float4Array	float4[]	[(float, float, float, float)]
FloatArray	float[]	[float]
Frame4d	frame4d	float, float, float, float, float, float, float, float, float, float, float, float, float, float, float, float
Frame4dArray	frame4d[]	[Gf.Matrix4d(float, float, float, float, float, float, float, float, float, float, float, float, float, float, float, float)]
Half	half	float
Half2	half2	(float, float)
Half2Array	half2[]	[(float, float)]
Half3	half3	(float, float, float)
Half3Array	half3[]	[(float, float, float)]
Half4	half4	(float, float, float, float)
Half4Array	half4[]	[(float, float, float, float)]
HalfArray	half[]	[float]
Int	int	int
Int2	int2	(int, int)
Int2Array	int2[]	[(int, int)]
Int3	int3	(int, int, int)
Int3Array	int3[]	[(int, int, int)]
Int4	int4	(int, int, int, int)
Int4Array	int4[]	[(int, int, int, int)]
Int64	int64	int (long in Python2)
Int64Array	int64[]	[int] ([long] in Python2)
IntArray	int[]	[int]
Matrix2d	matrix2d	float, float, float, float
Matrix2dArray	matrix2d[]	[Gf.Matrix2d(float, float, float, float)]
Matrix3d	matrix3d	float, float, float, float, float, float, float, float, float
Matrix3dArray	matrx3d[]	[Gf.Matrix3d(float, float, float, float, float, float, float, float, float)]
Matrix4d	matrix4d	float, float, float, float, float, float, float, float, float, float, float, float, float, float, float, float
Matrix4dArray	matrix4d[]	[Gf.Matrix4d(float, float, float, float, float, float, float, float, float, float, float, float, float, float, float, float)]
Normal3d	normal3d	Gf.Vec3d(float, float, float)
Normal3dArray	normal3d[]	[Gf.Vec3d(float, float, float)]
Normal3f	normal3f	Gf.Vec3f(float, float, float)
Normal3fArray	normal3f[]	[Gf.Vec3f(float, float, float)]
Normal3h	normal3h	Gf.Vec3h(float, float, float)
Normal3hArray	normal3h[]	[Gf.Vec3h(float, float, float)]
Point3d	point3d	Gf.Vec3d(float, float, float)
Point3dArray	point3d[]	[Gf.Vec3d(float, float, float)]
Point3f	point3f	Gf.Vec3f(float, float, float)
Point3fArray	point3f[]	[Gf.Vec3f(float, float, float)]
Point3h	point3h	Gf.Vec3h(float, float, float)
Point3hArray	point3h[]	[Gf.Vec3h(float, float, float)]
Quatd	quatd	Gf.Quatd(float, Gf.Vec3d(float, float, float))
QuatdArray	quatd[]	[Gf.Quatd(float, Gf.Vec3d(float, float, float))]
Quatf	quatf	Gf.Quatf(float, Gf.Vec3f(float, float, float))
QuatfArray	quatf[]	[Gf.Quatf(float, Gf.Vec3f(float, float, float))]
Quath	quath	Gf.Quath(float, Gf.Vec3h(float, float, float))
QuathArray	quath[]	[Gf.Quath(float, Gf.Vec3h(float, float, float))]
String	string	str
StringArray	string[]	[str]
TexCoord2d	texCoord2d	Gf.Vec2d(float, float)
TexCoord2dArray	texCoord2d[]	[Gf.Vec2d(float, float)]
TexCoord2f	texCoord2f	Gf.Vec2f(float, float)
TexCoord2fArray	texCoord2f[]	[Gf.Vec2f(float, float)]
TexCoord2h	texCoord2h	Gf.Vec2h(float, float)
TexCoord2hArray	texCoord2h[]	[Gf.Vec2h(float, float)]
TexCoord3d	texCoord3d	Gf.Vec3d(float, float, float)
TexCoord3dArray	texCoord3d[]	[Gf.Vec3d(float, float, float)]
TexCoord3f	texCoord3f	Gf.Vec3f(float, float, float)
TexCoord3fArray	texCoord3f[]	[Gf.Vec3f(float, float, float)]
TexCoord3h	texCoord3h	Gf.Vec3h(float, float, float)
TexCoord3hArray	texCoord3h[]	[Gf.Vec3h(float, float, float)]
TimeCode	timecode	float
TimeCodeArray	timecode[]	[float]
Token	token	str
TokenArray	token[]	string
UChar	uchar	ord(char) (where char is a single letter string)
UCharArray	uchar[]	[ord(char)] (where char is a single letter string)
UInt	uint	int
UInt64	uint64	int (long in Python2)
UInt64Array	uint64[]	[int] ([long] in Python2)
UIntArray	uint[]	[int]
Vector3d	vector3d	Gf.Vec3d(float, float, float)
Vector3dArray	vector3d[]	[Gf.Vec3d(float, float, float)]
Vector3f	vector3f	Gf.Vec3f(float, float, float)
Vector3fArray	vector3f[]	[Gf.Vec3f(float, float, float)]
Vector3h	vector3h	Gf.Vec3h(float, float, float)
Vector3hArray	vector3h[]	[Gf.Vec3h(float, float, float)]

2. Get Reference From a String

   Use Sdf.ValueTypeNames.Find(string) to get the reference from a string (valid inputs are the left column in the table above)

3. Exact Value

Look up the exact value for TypeName in the Sdf.ValueTypeNames module ( Sdf.ValueTypeNames.Color3h for example is valid):

from pxr import Sdf

print(dir(Sdf.ValueTypeNames))

# output is: ['Asset', 'AssetArray', 'Bool', 'BoolArray', 'Color3d', 'Color3dArray', 'Color3f', 'Color3fArray', 'Color3h', 'Color3hArray', 'Color4d', 'Color4dArray', 'Color4f', ... snipped ]

Working with Attributes

You can call the prim_ref.CreateAttribute(name, type) function to create the attribute, and we can use the information above to select a valid type. It returns a reference to the attribute created, which we can set with attribute_ref.Set(value), and again we can construct a valid value by looking up the constructor above.

from pxr import Usd, UsdGeom

stage_ref = Usd.Stage.Open('stage.usda')

# get a reference to the Xform instance, this works fine since it is also a Usd.Prim
xform_ref = UsdGeom.Xform.Define(stage, '/XformPrim')

# create an attribute reference, using an explicit reference to the type
weight_attr = xform_ref.CreateAttribute('weight', Sdf.ValueTypeNames.Float)

print(weight_attr.Get()) # prints empty string for default Float values, not 0!

print(weight_attr.Get() == None) # prints "True"
print(weight_attr.Get() == 0) # prints "False"

# to set an attribute we use the attribute_ref.Set(value) function
weight_attr.Set(42.3)

print(weight_attr.Get()) # prints "42.3"

# also, you can chain calls like so
print(xform_ref.GetPrim().GetAttribute('weight').Get()) # prints "42.3"