Re: [PATCH] Implement SVG plotting

[Bill Allombert <Bill.Allombert@math.u-bordeaux.fr>]

On Wed, Jan 18, 2017 at 04:34:43PM +0000, Jeroen Demeyer wrote:
> On 2017-01-18 16:28, Bill Allombert wrote:
> >The #define ENABLE_PLOT_xxx are not needed.
> >Since only one is linked anyway, all engine should define the same symbol
> 
> I disagree because I think that it should be possible to link multiple
> plotting engines. My patch allows multiple plotting engines in the PARI
> library, so it would be an artificial restriction that only one plotting
> engine can be linked in the gp program.
> 
> Actually allowing multiple plotting engines would require some non-trivial
> changes to the config system, that is why I did not do that.

The set of plotting engine linked to libpari must not depend on
Configure and must not incurr dependency on other libraries.
Otherwise the libpari ABI become a nightmare.

So we should add plotps and plotsvg to libpari but not the others.

The reason we support several plotting engines is because we wanted
to support plateforms where the available plotting engines did not
work.

For example plotfltk was added for non-X platforms (MacOS, windows
before plotwin32 was added), plotQt was added for Qt-based hand-held
device, plotps was added for MacOS when plotfltk failed to work anymore.

There is little purpose for GP to provide both X and fltk at the same time.

Cheers,
Bill.