1     Definition 2     Functional Requirements 3     Syntax
4     Semantics 5    Conformance Testing 6     Performance Assessment

1      Definition

The Pose Matrix Data Type expressing the position, orientation, and scale of an object in a Virtual Space through a homogeneous 4×4 transformation matrix thus providing an explicit and implementation‑neutral representation of rigid or
scaled transforms relative to a specified Reference Frame.

2      Functional Requirements

  • Transformation Encoding – The Data Type shall encode a 4×4 homogeneous matrix representing translation, rotation, and scale in row-major order.
  • Reference Frame Specification – The Data Type shall allow optional declaration of the coordinate system in which the matrix is expressed (e.g., UserView, World, Camera).
  • Numeric Precision Declaration – The Data Type shall allow an explicit indication of the precision of stored values (float32 or float64).
  • Extensibility – The format shall remain compatible with future extensions such as transform decompositions or hierarchical frame relationships.

3      Syntax

https://schemas.mpai.community/OSD/V1.5/data/PoseMatrix.json

4      Semantics

Table 1 provides the semantics of the components of Spatial Cue.

Table 1 – Semantics of the Spatial Cue

Label Description
Header Pose Matrix Header – Standard “OSD-PMX-Vx,y”.
MInstanceID ID of Virtual Space the cue refers to.
PoseMatrixID Identifier of Spatial Cue entry.
Matrix A homogeneous 4×4 transformation matrix (16 numbers) in row-major order. It encodes position, orientation, and scale of an object within the declared Reference Frame.
ReferenceFrame Optional name of the coordinate system in which the Matrix is defined (e.g., UserView, World, Camera). Used to disambiguate spatial interpretation.
Precision Declares the numeric precision of the matrix values. One of:
float32 – 32‑bit floating‑point representation
float64 – 64‑bit floating‑point representation
DataExchangeMetadata Metadata optionally supporting regulated exchange of Pose Matrix data as defined by AIF V3.0.
Trace Provenance information aligning with AIF V3.0, identifying the producing AIM and the time of generation.
DescrMetadata Descriptive metadata (maximum 2048 characters) providing human-readable notes or documentation associated with the pose.

5     Conformance Testing

A Data instance Conforms with V1.5 Pose Matrix (OSD-PMX) if:

  1. Its JSON Object validates against its JSON Schema.
  2. Any included  JSON Object validates against its JSON Schema.
  3. All Data in the JSON Object:
    1. Have the specified Data Types.
    2. Conform with the Qualifiers signaled in their JSON Schemas.

6     Performance Assessment