HdSampledDataSource Class Referenceabstract

A datasource representing time-sampled values. More...

+ Inheritance diagram for HdSampledDataSource:

Public Types

using Time = float
 

Public Member Functions

 HD_DECLARE_DATASOURCE_ABSTRACT (HdSampledDataSource)
 
virtual VtValue GetValue (Time shutterOffset)=0
 Returns the value of this data source at frame-relative time shutterOffset. More...
 
virtual bool GetContributingSampleTimesForInterval (Time startTime, Time endTime, std::vector< Time > *outSampleTimes)=0
 Given a shutter window of interest (startTime and endTime relative to the current frame), return a list of sample times for the caller to query with GetValue such that the caller can reconstruct the signal over the shutter window. More...
 

Detailed Description

A datasource representing time-sampled values.

Note that implementations are responsible for providing cache invalidation, if necessary.

Definition at line 161 of file dataSource.h.

Member Function Documentation

◆ GetContributingSampleTimesForInterval()

virtual bool GetContributingSampleTimesForInterval ( Time  startTime,
Time  endTime,
std::vector< Time > *  outSampleTimes 
)
pure virtual

Given a shutter window of interest (startTime and endTime relative to the current frame), return a list of sample times for the caller to query with GetValue such that the caller can reconstruct the signal over the shutter window.

For a sample-based attribute, this might be a list of times when samples are defined. For a procedural scene, this might be a generated distribution. Note that the returned samples don't need to be within startTime and endTime; if a boundary sample is outside of the window, implementers can return it, and callers should expect it and interpolate to startTime or endTime accordingly. If this call returns true, the caller is expected to pass the list of outSampleTimes to GetValue. If this call returns false, this value is uniform across the shutter window and the caller should call GetValue(0) to get that uniform value.

Implemented in UsdImagingDataSourceXformMatrix, UsdImagingDataSourceXformResetXformStack, HdRetainedTypedSampledDataSource< T >, UsdImagingDataSourceExtentCoordinate, HdRetainedSampledDataSource, UsdImagingDataSourcePointInstancerMask, UsdImagingDataSourceRelationship, and UsdImagingDataSourcePointInstancerXforms.

◆ GetValue()

virtual VtValue GetValue ( Time  shutterOffset)
pure virtual

Returns the value of this data source at frame-relative time shutterOffset.

The caller does not track the frame; the scene index producing this datasource is responsible for that, if applicable. Note that, although this call returns a VtValue for each shutter offset, the type of the held value is expected to be the same across all shutter offsets. This call is expected to be threadsafe.

Implemented in UsdImagingDataSourceXformMatrix, UsdImagingDataSourceXformResetXformStack, HdRetainedTypedSampledDataSource< T >, HdRetainedSampledDataSource, UsdImagingDataSourceExtentCoordinate, UsdImagingDataSourcePointInstancerMask, UsdImagingDataSourcePointInstancerXforms, and UsdImagingDataSourceRelationship.


The documentation for this class was generated from the following file: