Local coordinates are always considered relative to the last point that was used, created or selected. The Utilities -> Id command allows you to make a reference to one point (see Id). Then, to define points using local coordinates referring to the same point, use Options and Fixed Relative when entering each point. The last point selected or created before using this will be the origin of the local coordinate system. It is also possible to enter this central point by its coordinates.
The following are valid examples of defining points using local coordinates:
Example (1):
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