Re: svg : gnuplot_plot_1

[Ethan A M. <sf...@us...>]

On Thursday, October 20, 2011 03:34:51 pm pl...@pi... wrote:
 
> I really don't see why the needs of the demo script should have any 
> impact on how the program functions.

My point was that I really don't know how the "typical user" operates.
The only experience I have to work from is my own, and my use has been
script-driven generation of web pages.  I only mentioned the demo set
because that is an example everyone has access to, not because it has
any particular importance on its own.

> The svg file is an automonmous file format , I would have thought the 
> viewing it in an svg viewer would have been the reference condition.

Maybe for some users it is.  So far everyone I've heard from has been
generating svg plots explicitly to embed them in some larger document.

> Why would anyone want to set the id , js_id or jsname at all ?

I have been trying to explain that.  If you are creating dynamic content
from a script, the script needs to create an svg (or HTML5 canvas) plot with
named tags, and then also create javascript code that acts on those named
tags.  So it needs to specify a non-redundant name for each plot, and that
name must be legal in both xml and javascript.  If gnuplot changes the
requested name to something else, it breaks the connection between the
plot and the associated javascript.

> >> I don't see right away where you could have multiple plots without an
> >> HTML wrapper
>
> > Christoph points out that the current scheme doesn't deal well with
> > multiplot mode.  All the plots in a multiplot get the same name.
> 
> See my reply to Christoph, they don't get the same value, one is wrong. 
> I found what looks like a simple slip up in the source.

I think you are misinterpreting something.  Try running "multiplt.dem"
in the demo set.  Each of the 4 graphs in the resulting svg file contains
plots named "multiplt_plot_1", "multiplot_plot_2", and so on.
So we end up with 4 copies of each, which is a problem.

The "gnuplot_canvas" identifier is attached to the top-level group that
bounds the whole document so that the mousing code can find it.  
Its name is purely arbitrary and has nothing to do with any of the
individual plots.

	Ethan