Re: wxt terminal - questions

[Chris K <gnu...@li...>]

Ethan A Merritt wrote:
> Two questions
> 
> (1) 
> I've been poking about in the code, and so far as I can
> see the code assumes that character strings passed to Pango
> will be interpreted as UTF-8.  E.g. the following comment:
> 
>   /* pango needs a string encoded in utf-8. We use g_convert from glib.
>    * gp_cairo_get_encoding() gives the encoding set via 'set enconding'
>    * memory allocated for enhanced_text_utf8 is freed at the end of 
>    * gp_cairo_enhanced_flush */
>   string_utf8 = g_convert(string, -1, "UTF-8", gp_cairo_get_encoding(plot), NULL, NULL, NULL);
> 
> But this doesn't happen. My machines are normally set to a UTF-8 locale,
> and all characters I type into gnuplot are UTF-8 encoded.  
> But the multibyte characters are mangled when displayed in the wxt plot window.
> The same strings are properly displayed in x11 (when set to multibyte mode)
> and in gd (which by default uses UTF-8).  So I know they are correctly
> stored inside gnuplot. What's going wrong in wxt?
> 
> (2)
> I happened across a page of sample plots from another plotting program,
> and was struck by how useful transparency can be in some cases.
> In particular in the case of overlapping histograms
>    http://sourceforge.net/project/screenshots.php?group_id=15494
> I think it would be possible to support this in gd.trm and svg.trm,
> but I'm not sure about any other terminals.   Do the Cairo graphics
> primitives support an alpha channel, so that wxt.trm could use this also?
> 
> 

The filled example here
http://sourceforge.net/project/screenshots.php?group_id=15494&ssid=8404
does look good.

Yes, Cairo is very very happy with RGBA for Alpha channel transparency
information. ( http://cairographics.org/samples/operator_atop.html )

I assume the trick is : how do you specify transparency with gnuplot?

-- 
Chris
#292 http://highclearing.com/index.php/archives/2006/04/07/4991#comment-8388