Study Figure 17-4 to locate these points: (0,0); (-2,2); (6,2); (6,3);

 

(10,0); (6,-3); (6,-2); (-2,-2); (0,0). Draw a straight line between each

 

point in the order listed. (You should have drawn an arrow.) This is a

 

simple demonstration of defining a vector image when in HP-GL/2

 

mode.

 

 

 

 

Note

To specify a point when programming an application, you must

 

always give a complete X,Y coordinate pair; the X coordinate is first

 

and the Y coordinate second. This manual shows coordinate pairs

 

in parentheses (X,Y) for clarity. Do not use parentheses in your

 

command sequence.

 

Using the default HP-GL/2 coordinate system, the origin is in the

 

 

lower left corner of the PCL Picture Frame, as shown in Figure 17-5.

 

Using the IP or IR commands, you can move the origin to other

 

locations. Then, using the SC command, you can define practically

 

any unit coordinate system. (This process is discussed in more

 

detail later in this chapter under “Scaling,” and also in Chapter 19.)

 

 

 

 

 

 

 

 

Figure 17-5 The Default HP-GL/2 Coordinate System

17-16An Introduction to HP-GL/2 Vector Graphics

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HP 5961-0509 manual Mode, Parentheses X,Y for clarity. Do not use parentheses in your