The QUAD directive in a coordinate system definition is used to set the orientation of the coordinate system.
This directive takes an integer value from -4 to 4. 0 or 1 indicate the normal right-handed Cartesian system, where X increases to the east, and Y increases to the north. This is the default quadrant.
Quadrants are numbered counterclockwise:
2 |
1 |
3 |
4 |
A negative value will cause the axes to be swapped after the appropriate quadrant is applied.