[Scilab-Dev] plotframe obsoleted

[Serge Steer]

Stéphane Mottelet a écrit :
> François Vogel a écrit :
>> mottelet at dma.utc.fr said on 28/06/2008 10:57:
>>> maybe you can create an empty axes and then turn on everything
>>> at hand
>>
>> Yes, this is working, thanks.
>>
>>> Now I am an expert of the new graphics :-) (I've almost
>>> finsished porting the plotlib).
>>
>> Just for my education, why is the plotlib still needed with the
>> current Scilab5 graphics?
>>
>> I have used it extensively from Scilab 2.7 to Scilab 4. Shame on me,
>> I never took the time to thank you for having made it available, so
>> let's state it now: this saved me a LOT of time in the past, many
>> thanks.
>>
>> I'm now in the process of converting my scripts so that they can work
>> with Scilab 5 and the new graphics. This is... well, not so easy due
>> to numerous graphics bugs (but IMO this is largely due to java, not
>> the new graphics scheme itself). However I must admit that, once
>> you've bought your driving license, new graphics are easier/clearer
>> to use than the old graphics. I've been using the plotlib mainly
>> because I could not achieve what I wanted with the old graphics. With
>> the new graphics any calls to the plotlib have found a Scilab-only
>> replacement. Just wondering.
>>
>> Francois
> You are (mostly) right, but, like a (dead) friend  of mine used to say
> : the devil is in the details. The new
> "object-oriented" structure was missing in the old graphics and I have
> to say that porting the plotlib
> has been sometimes just replacing numerous lines of code by one line
> or even nothing at all.
>
> Some reasons for which the plotlib is still needed (at least for my
> own usage) :
>
> -In Scilab, having default colors, e.g. obtained in a default entity
> handle like gda()
> given by indices making only sense with respect to a default colormap
> of the
> default entity gdf(), is (to me) completely useless once you need to
> plot nice
> shaded plots and still control the colors of line plots, foreground,
> background...
> What it really still missing is a decent colormap handling. Having one
> colormap for the whole figure is
> a real problem when you have shaded  plots (like pcolor, surf,...) 
> together with line plots. In the
> plotlib the colormap for shaded objects is handled separately. This
> also allows to have a "caxis"
> macro like in Matlab.
> The big deal is, in fact, when will Scilab switch to truecolor ?
planned for a future release
> -Another point : legends and colorbars are in no way linked to  the
> axes they belong to. For
> example, once you have plotted the legend, you can do it again and
> again, the new entity
> will never replace the previous one. Legends should be handled like
> (x,y,z) labels and title.
> Of course, this is only needed for people using Scilab like a
> calculator (i.e. writing a lot
> of stuff directly on the command line)... but there are still many !
> Same thing for
> the colorbar.
I am currently working on the legend, more specifically i extend the
Legend graphic object. You can try it with the tomorrow version. There
are still some details/bugs to be fixed...
But please let me know your criticism and advices...

> -Last point, many users have complained about XMLlab using the old
> graphics; I thought
> it was easier for me to port the plotlib instead of modifying the XSL
> stylesheets to generate  all
> the needed stuff. I was right. But this adds additionnal bottlenecks,
> and as a result everything is
> slower than before. Hopefully it is possible to speed up things, e.g.
> by directly modifying
> the "data" field in order to make fast animations.
>
Of course animations should be done in quite different manner (e.g. by
directly modifying
the "data" field instead of rebuiling the objects) with the new graphic
to be efficient and to avoid allocating a lot of memory.
> S.
>
>