Re: Should 'dashlength' affect only builtin or also custom dash patterns?

[sfeam <sf...@us...>]

On Monday, 02 June 2014 11:18:08 AM Christoph Bersch wrote:
> 
> Zitat von sfeam <sf...@us...>:
> 
> > On Sunday, 01 June 2014 07:34:53 PM Christoph Bersch wrote:
> >
> >> I've seen, that different terminals handle the `dashlength` option
> >> differently:
> >>
> >> set termoption dashlength 1
> >> plot x dt 2, 2*x dt '.-'
> >> pause -1
> >>
> >> set termoption dashlength 3
> >> replot
> >>
> >> `qt`: dashlength affects only the custom dash pattern
> >> `wxt`: both patterns are stretched
> >> `post`: only the builtin patterns are affected
> >>
> >> This behaviour should be equal for all terminals.
> >
> > Good point.
> 
> I've had a quick look at the Qt-documentation, but I couldn't find an  
> option to change the dash length for the builtin patterns.

Correct.

> Another thing I've seen is, that for some terminals the dash pattern  
> length depends on the linewidth, e.g. for the `qt` terminal. For  
> others, like the `wxt` terminal it doesn't.

Qt docs:  "the dash pattern is specified in units of the pens width"

> [...] we should try to have similar  
> behavior across the terminals, or at least try to.

For output devices that really do provide their own dash types
we can't do much other than use them as provided.  
But we can aim for consistent behavior of the new "custom"
dashtypes.  I kind of like the Qt approach of scaling the
dashlength with the line width.  I'm not certain that would
work for all terminal types but it's something to think about.

	Ethan