HP PCL/PJL reference (PCL 5 Printer Language) - Technical Reference Manual Part II

21-14 The Polygon Group EN
Figure 21-9 Filling Polygons: Non-Zero Winding Fill Method
Drawing Circles in Polygon Mode
Polygon mode interprets the Circle (CI) command differently than the
other HP-GL/2 commands. The printer treats a circle as a complete
subpolygon. The printer automatically closes the first polygon (if any)
before starting the circle, and uses the first coordinates (if any) after
the circle is drawn to start a new subpolygon.
If you did not close your first polygon completely before sending the
CI command, the printer automatically closes the polygon by adding
a point (at the starting point of the previous subpolygon). This can
change your current pen location and the placement of the circle in
your polygon, resulting in an inaccurate polygon.
`Approximating Polygon Buffer Use
You can use the following formula to estimate how much buffer space
a polygon consumes. Each point in a polygon uses 8 bytes. For
example, the minimum number of points the printer will hold is 512.