Re: dashes again

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

On Tuesday 16 February 2010 14:20:45 Petr Mikulik wrote:
> I raise questions about dash line patters from time to time (see e.g.
> messages "unified dashes"). Usually it happens when I try to do
> 	set term x11 dash
> 	plot x,-x,1,2,3
> and it comes out solid :-)
> 
> 1. It did not work in the morning, I had to find an older e-mail and
>    find there
>          xrdb -merge < Gnuplot.app-defaults
> 
> 1a. That seems to be a problem for ordinary users, because
>    file  Gnuplot.app-defaults  is not "make install"ed.

Yes it is.  There is some dispute, however, about whether there is a
standard place to install it. To resolve this, Christoph Junghans
added an explicit configuration option.  It is noted in the Changelog
as:
 
2010-02-07  Christoph Junghans (ottxor)
        * configure.in share/Makefile.am src/Makefile.am src/gplt_x11.c
        src/variable.c: Configurable X11 application resource path.
        Bug #2931287 #219323

> 1b. Further, gnuplot-x11 does not detect automatically that it cannot
>    draw dash lines because that xrdb command was not executed. Why it
>    does not help? 

Correction:  There is no requirement to run xrdb.  xrdb is one 
particular way you can modify the current X resource values from the
command line, but it is not the only way, not even the usual way.

>    It should write a warning when "gnuplot -dashed" or 
>    "set term x11 dash".

Gnuplot_x11 is not even running yet at the time you enter either of
these commands.  It is started up later, at the time of the first plot.

> 2. "dash" support was added into wxt terminal in June 2009, just after
>    4.4 branch separation. Shouldn't this be (back)ported to 4.4?

It is on my list of patches to apply after 4.4.0 is released.
I posted the full list the other day, but here it is again:
   winmain_va_copy      Allows building with Visual C
   wxt_dashed           set term wxt ... {dashed|solid} {dashlength <dl>}
   x11_mousewheel
   wxt_mousewheel
   pow_overflow         if i**j would cause integer overflow, return a float instead
   int_overflow         Check internal integer multiplications for overflow
   tikz                 remove conditional tests for version 4.3
   candle_width         optional 6th column containing box width
   rmargin              tweak left and right margins to be more like those prior to 4.2.4
   jw-refactor          clean up the execute-from-string operations lf_push/lf_pop
   cc-for-build         fix for building documentation during cross-compilation
   percent_s            support the "%s" format specifier in strftime()
   Kalinin_metapost     Fix inheritance of line thickness by text strings
   suppress_PDFMark     rearrange postscript prolog to allow customization
   timefmt              handle evaluated input values for time format "%s"
   init_func_points     initialize full coordinate structure for 2D functions

These are all non-trivial changes that were made subsequent to the code 
freeze for 4.4.0 (by "non-trivial" I mean "I was afraid they might possibly
break something).  During the -rc1 period I've only been applying bug fixes
and "trivial" changes to things like documentation.

> 3. Windows terminal supports solid, dash, dot-dash patterns via
>    its menu in the graph window, but it does not support
>       set term windows {solid|dashed}
>    Benjamin, can you please implement it?
> 
> 4. Should "all usual" terminals support both options
>       {solid|dash} {dashlength <dl>}  ?
>    Currently:
>      x11, svg: {solid|dash}
>      wxt, postscript: {dashed|solid} {dashlength <dl>}
>      png, pdf: {dashlength <dl>}

Not sure I understand your proposal.  Which terminals should be changed?

> and
>       set termoption {solid|dashed}

That would be tricky for postscript or pdf output if the file already
is open, since the setting is currently done in the file header.
But maybe it is possible.

	Ethan