### Pen definition

A virtual pen is defined by its conventional number (0 to 15), and its attributes. Currently, the attributes can be

- COLOUR, an integer code for the colour. The integer can take values from 0 to 15 with undefined conventions, because the colour table is dynamically selectable on some devices. (e.g. ARGS). On a non-color device with default terminal settings, it corresponds to an intensity level. 0 is the brightest available intensity. Values 1 to 15 correspond to increasing intensities, scaled to cover the full range of available intensities on the current device. As most devices have three intensity levels, 1-5 will give the dimmest intensity, 6-10 the intermediate one and 11-15 the brightest (i.e. the same as 0).

- DASHED pattern, an integer from 1 to 7 with the following significance
  1. Solid line
  2. Short dashed line
  3. Dotted line
  4. Short dash - Dot line pattern
  5. Long dashed line
  6. Long dash - Dot
  7. Short dash - Long dash
  The first four attributes corresponds to the standard GKS (Graphic Kernel System) convention, and the hardware generation of the output device may be used. It is not used for the other ones.
- WEIGHT, an integer from 1 to 5 giving the thickening factor of the line. Hardware generation may be used.

A pen is loaded and defined by command PENCIL Ipen /DASHED Idash /WEIGHT Iweig /COLOUR IColo /DEFAULT
All subsequent plots will be done with this virtual pen, until a new command PENCIL is issued. If the attributes are not given, the previous ones (resulting from the last definition) are used. If a device has not the required capability, the code is ignored. The /DEFAULT option can be used to reset the default settings of the attributes which are not specified. If no pen number is specified, the /DEFAULT option reset all default attributes to every pen.