Relative coordinates VS. Absolute coordinates

Relative Coordinates (default in GstarCAD)

When we use Relative Coordinates, we type the X and Y coordinates relative to the last point, it’s always about the last point.

Absolute Coordinates

When we use Absolute Coordinates, we type X and Y coordinates on the current coordinate system to locate the point relative to the origin. It’s always about the origin, the absolute (0,0).

Draw a rectangle: First corner point coordinates (100,200), length 400, width 300

When using Relative Coordinates, we can execute Rectangle command and specify the first corner point by entering coordinates (100,200), and when prompted to specify other corner point, enter (400,300), as shown in the following picture,

But things are different when using Absolute Coordinates, if we still specify the first corner point (100,200) and then enter (400,300), we get a rectangle 300 by length and 100 by width.

The thing is the other corner point coordinates we enter are relative to the origin, not the last point any more, so here we should enter (500,500)

How to switch between using relative coordinates and absolute coordinates ?

As said, DYNPICOORDS is the system variable controls what you enter: relative coordinates or absolute coordinates.

When we enter DYNPICOORDS and press Enter key, we’ll get the following prompt showing the current DYNPICOORDS value and asking us to enter a new value, as shown in the following picture,

By default, the value for DYNPICOORDS is 0, which means we are using relative coordinates.

If we want to use absolute coordinates, just enter 1 and press Enter key.

To switch back to relative coordinates, enter 0.

A Quick Tip

If we are using absolute coordinates and we want to enter relative coordinates without changing the value for DYNPICOORDS, just add a “@” before the point coordinates (Format: @X,Y)