Re: grouping available terminals together

[Ethan A M. <merritt@u.washington.edu>]

On Thursday 08 February 2007 23:53, Timoth=E9e Lecomte wrote:
> Maybe we should change the terminal API to:
> * rgb colors
> * dash patterns
>=20
> and the default linetypes would be handled by the core.
> On a screen terminal:
> -lt 1 would be red
> -lt 2 would be blue
> ...
> On a print-oriented terminal:
> -lt 1 would be red/solid
> -lt 2 would be blue/dash

Isn't that exactly what we have now?

I am speculating, since the decision must date back to=20
the origins of gnuplot. But I think that the reason there
was no mechanism for specifying particular colors, and=20
still is no mechanism for specifying particular dot/dash
patterns, is that these were unchangeable properties of
the physical devices.  On a pen plotter you could request
pen #1, pen #2 or pen #3, but it was up to the operator to
choose the pen physically sitting in slot #1.  A slightly
more recent generation of printers offered a small number
of dot/dash patterns for line drawing, but gave you no
mechanism for defining new ones.  So the control program,
gnuplot in this case, can do no better than select=20
#1, #2, and so on.=20

=2D-=20
Ethan A Merritt
Biomolecular Structure Center
University of Washington, Seattle 98195-7742