HP LaserJet 4100 HP PCL/PJL reference (PCL 5 Printer Language) - Technical Ref - Page 141

z If the end point is the same as the current pen location, a circle is drawn, with its diameter being the distance between the current pen position and the intermediate point. z If the current pen position, intermediate point, and end point are collinear, a straight line is drawn. z If the intermediate point does not lie between the current pen location and the end point, and the three points are collinear, two lines are drawn, one from the current pen location and the other from the end point, leaving a gap between them. Refer to the following illustration. Both lines extend to the PCL Picture Frame limits or current window. Figure 20-21 Table 20-31 Example: Using the RT Command (Relative Arc Three Point) ECE Reset the printer. EC%ØB Enter HP-GL/2 mode. IN; Initialize HP-GL/2 mode. EN RT, Relative Arc Three Point 20-49