Re: [Maxima-discuss] draw2d: transparent background in allocated plots

[Mario R. <bio...@te...>]

El 17/03/15 a las 22:48, Nijso Beishuizen escribió:
> Dear all,
>
> I tried the maxima code for multiplots from here:
> http://riotorto.users.sourceforge.net/gnuplot/multiplots/index.html
>
> Specifically, this code for putting a graph on top of another graph:
>
>
> load(draw);
> draw(
>      columns=2,
>      gr2d(explicit(sin(x), x, -1, 1)),
>      gr2d(allocation = [[0.1,0.25], [0.3,0.5]],
>           color = red,
>           explicit(x^2, x, -1, 1)),
>      gr2d(explicit(cos(x), x, -1, 1)),
>      gr2d(allocation = [[0.6,0.2], [0.3,0.3]],
>           color = black,
>           parametric(u*cos(u),u*sin(u), u, 0, 25)) )$
>
> But the top graph has a solid white background instead of the
> transparent background as shown on the riotorto site.

This example was created with Gnuplot 4.4. Later, Gnuplot 4.6 introduced 
some changes which were not compatible with previous versions and some 
changes had to be made in Maxima so that background color could work again.

>
> The gnuplot code for these figures show that a rectangular region with a
> solid white background is created for both figures:
>
> set obj 1 rectangle behind from screen 0.0,0.0 to screen 1.0,1.0
> set style rectangle fillcolor rgb '#ffffff' fs solid 1.0 noborder

This is the workaround I found to allow background colors. In fact, it 
was suggested to me by one of the Gnuplot developers, if I recall correctly.

> What I expected to see is something like "set style rectangle fillstyle
> empty". It seems that "fs solid" is hardcoded in maxima (and changing to
> "fs empty" is sufficient to make it work), or is there another way to
> trigger the background transparency?
In its current state, background is set to white by default and 
transparency is lost. At first sight, it shouldn't be hard to change 
this behavior. I'll take a look at it.

>
>
> Best,
> Nijso
>
>
>
>

Thanks for reporting this bug.

--
Mario