- Abstract things that need tracking, e.g. characters, props, stage sets, scenes, sequences, shots.
- Reference Asset
- Data files and physical props that are associated with Entities.
- 3D Stereo, for left and right eyes. Its better to call it stereo than 3d, since so much of the rest of the VFX pipeline is already has a meaning for 3D.
- A string consisting of only letters and numbers (no spaces or punctuation). Unicode not supported. Something that is a word could end up as a file-name, so it needs to be a fairly neutral, unix/windows friendly string.
- A list of any characters, could be unicode.
- A string representing a distance, should include units. e.g. 50mm 3.5'
- Whole numbers
- numbers including fractional digits.