API Reference — dna/layers/JointBehaviorMetadataReader

class DNAAPI JointBehaviorMetadataReader : public virtual DefinitionReader

Read how each joint's translation, rotation and scale are represented internally when the rig is evaluated at runtime.

When to use this

Reach for this interface when you need to read the representation contract for specific joints — for example, to mirror the rig runtime's evaluation strategy in a custom solver or to validate that DNA joint metadata matches your expected configuration. Use the paired writer interface when you need to assign these values rather than read them.

Example

// reader is a fully loaded Reader* obtained from BinaryStreamReader::create()
const JointBehaviorMetadataReader* meta = reader;

std::uint16_t jointIndex = 0u;  // must be < reader->getJointCount()

TranslationRepresentation  txRep  = meta->getJointTranslationRepresentation(jointIndex);
RotationRepresentation     rotRep = meta->getJointRotationRepresentation(jointIndex);
ScaleRepresentation        sclRep = meta->getJointScaleRepresentation(jointIndex);
// txRep, rotRep, sclRep now carry the representation enums used by the rig evaluator

Parameters

Name Type Description
jointIndex std::uint16_t required. A joint's position in the zero-indexed array of joints. Must be less than the value returned by getJointCount.

Returns

  • getJointTranslationRepresentation → TranslationRepresentation — the internal representation used for this joint's translation component during evaluation.
  • getJointRotationRepresentation → RotationRepresentation — the internal representation used for this joint's rotation component during evaluation.
  • getJointScaleRepresentation → ScaleRepresentation — the internal representation used for this joint's scale component during evaluation.

Constraints

  • jointIndex must be less than the value returned by getJointCount.

Watch out for

  • Implementors should inherit from Reader itself and not this class.
  • This metadata affects how joints are calculated, as the given representation is used internally by the implementation that evaluates them.
  • jointIndex must be strictly less than getJointCount(). The interface does not guard against out-of-range indices; passing an invalid index produces undefined behavior.
  • Do not subclass JointBehaviorMetadataReader directly. Implementations must inherit from Reader itself; this class is an accessor mixin only.