| Since | 18.0 |
<type> usd_primvarelement(<stage>stage, string primpath, string name, int index)
<type> usd_primvarelement(<stage>stage, string primpath, string name, int index, float timecode)
This function returns a value of an element in given array primvar on a given primitive.
<stage>
When running in the context of a node (such as a wrangle LOP), this argument can be an integer representing the input number (starting at 0) to read the stage from. The integer is equivalent to the string form referencing a particular input, e.g., “opinput:0”.
You can also use this argument to refer to a USD file (e.g., “/path/to/file.usd”), or to another LOP node’s cooked stage using the op: as the path prefix (e.g., “op:/stage/lop_node”).
primpath
The path to the primitive.
name
Primvar name (without namespace).
index
The index into the array.
timecode
The USD time code at which to evaluate the attribute. A USD time code roughly corresponds to a frame in Houdini. If not given, the time code corresponding to the current frame is used.
Returns
The value of an element in an existing array primvar, or zero/empty value if the primvar does not exist. Use usd_isprimvar if you want to check whether the primvar exists.
Examples ¶
// Get the value of some primvars on the cube primitive. float value = usd_primvarelement(0, "/geo/cube", "primvar_name", 3); v@element_2_at_current_frame = usd_primvarelement(0, "/geo/sphere", "foo", 2); v@element_2_at_frame_8 = usd_primvarelement(0, "/geo/sphere", "foo", 2, 8.0);
| See also | |
| usd | |
| usd_primvar |
|