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Coordinate System

The coordinate system in Alloverse has the following properties:

  1. One unit is 1 meter
  2. Coordinate system is right-handed. This implies…
  3. Negative X is left/west, positive X is right/east.
  4. Negative Y is down, positive Y is up.
  5. Negative Z is forward/north, positive Z is back/south.
  6. Positive rotation is counterclockwise about the axis of rotation.
  7. Rotations are always represented in radians.
  8. Y=0 is floor level in model space
  9. The neutral pose of all models, avatars, app UIs etc should should face towards positive Z, with “right” being positive X and “up” being positive Y.
  10. For textures, UV 0,0 is bottom-left, with positive U towards the right, and positive V upwards.
  11. The origin of an entity should be in its middle.

Rotation about Y axis is counterclockwise

Representation

Transforms are always represented using a 16-element transformation matrix. Such a 4x4 matrix is represented in data models with a column-major 16-element list of numbers.