Code 104 sets device-specific information. The param array must be a one dimensional INTEGER array. The number of elements required depends on the device driver. Conventionally, it contains two elements. The first element is the operation number and the second element is the value associated with that operation. See the documentation for each driver for information on any GESCAPE 104 operations supported by that driver.
For the HPGL plotter driver, this code is used to enable HPGL/2 capabilities. When HPGL/2 is used, polygons are sent to the plotter for rendering. With many plotting devices, this allows the polygons to be filled. When generating an HPGL file for import into other programs, it is often more desirable for the polygon to import as a single unit, rather than a series of lines. To enable HPGL/2, use the following code. Substitute the ISC for the HPGL plotter in place of ISC in line 40.
10 INTEGER Param(1)
20 Param(0)=1 ! HPGL Operation Number: 1 = HPGL/2 Flag
