Local Rotation
Rotation in 3D space can be represented using two vectors. Local rotation is a way to represent the rotation of an object relative to its own axes. This is in contrast to global rotation, which is relative to the world axes.
Axis representation
The game uses the X axis and the Z axis to represent the local rotation of an object. The Y axis is not used, as it is calculated from the X and Z axes.
The index of the axis is represented by an integer value. The following table shows the mapping between the integer value and the axis:
| Value | Vector (XYZ) | Axis |
|---|---|---|
-3 | ( 0, 0, -1) | Negative Z axis |
-2 | ( 0, -1, 0) | Negative Y axis |
-1 | (-1, 0, 0) | Negative X axis |
1 | ( 1, 0, 0) | Positive X axis |
2 | ( 0, 1, 0) | Positive Y axis |
3 | ( 0, 0, 1) | Positive Z axis |
Any other value is invalid.
Both blueprints and certain network packets use this representation to store the local rotation of an object.
Default rotation
The default rotation of a shape has an X axis of (1, 0, 0) and a Z axis of (0, 0, 1). This means that the X axis of the shape aligns with the X axis of its body, and the Z axis aligns with the Z axis of its body.
Blocks always have the default rotation, while parts and joints can have any local rotation.