voplot issues

[Nilesh Urunkar]

Dear Gerard,

You can install VOPlot on a server for the purpose of using it in a web
based fashion. Section d under clause 3 of the license which describes the
limitations of use, allows redistribution of VOPlot (binaries) if it is
being used as 3rd party tool. Using VOPlot in a web based fashion should be
viewed as usage of VOPlot as 3rd party tool and hence is perfectly legal.
Section 3a only restricts the use of the Program, Source Code and
Documentation in any other fashion except the usage allowed by section 3d.

At present there are limitations on redistribution of modified VOPlot
binaries and source code, since we would like to vet all the changes and
then integrate them into the main codebase for VOPlot with due credit to the
contributors. This will help us support VOPlot and related queries in a
better fashion going forward. In case, if any user modifies the source code
to implement one or more features in VOPlot, then we would like the user to
send us the modified source code so that we can review it and merge it with
main code branch so as to integrate the changes into VOPlot.

As for providing the functionality of creating a filter based on selected
set of points, we will be adding this in the next version of VOPlot.

Thanks & Regards,
Nilesh Urunkar

-----------------------------------------------
Senior Member of Technical Staff (VO-India)
Persistent Systems Pvt. Ltd.,
Bhageerath, 402 Senapati Bapat Road,
Pune - 411016, India.
Phone: + 91 (20) 25678900
Visit us at www.persistentsys.com


----- Original Message ----- 
From: "Gerard Lemson" <gerard.lemson at mpe.mpg.de>
To: <voindia at vo.iucaa.ernet.in>
Cc: "Gerard Lemson" <gerard.lemson at mpe.mpg.de>; <apps at ivoa.net>
Sent: Thursday, February 09, 2006 3:37 PM
Subject: voplot issues


> To whom it may concern
>
> I have been using VOPlot succesfully in a few use cases, which revealed
> some issues about which I want to ask some questions and give some
comments.
>
> 1.
> I have made the VOPlot applet available in web applications that allow
> querying of a relational database online.
> The user can select to have the result set plotted in a VOPlot applet.
> See http://www.g-vo.org/mpasims/QueryManager? for an example.
> This is excellent for quick evaluation of the result set online and is
great
> for
> demonstrations. However, referring to a recent email from Alex Szalay on
the
> IVOA
> on the ivoa mailing list, about the VOPlot licensing,
>
> "
> To me 3a means that a system manager cannot install this on
> a server -- rather every user has to download and install
> directly from India.
>
> I did not read this until now, but this will make it difficult
> to incorporate and use VOPlot broadly, like making it part of
> an archive interface external to VO India -- if this licence
> really means what it says.
> "
>
> I am no expert in reading license documents, so please can you let me know
> whether my use of the applet this way is legal ?
>
> 2.
> I noticed that a potentially very useful feature is absent in version
> 1.2 of VOPlot, as well as in the 1.2.1 source version.
> This feature is that, when one selects a subset of points in the plot,
> showing say column A vs column B, the same points will still be
highlighted
> when I switch to viewing say column C against column D.
> In the latest version of VOPlot the points are deselected.
> I have investigated the source code version (thanks very much for
providing
> this btw !)
> and found that a simple code change in the drawPlot(boolean, boolean)
method
> in
> com.jvbt.applets.PlotVOApplet seems to correct this.
> I have tested this out on users of private versions of the web based
> querying tool and they are enthousiastic about this feature. It is an
> example
> of a feature that is very hard to emulate for example in IDL.
>
> I understand there may be issues with such code changes and making them
> available
> to other users. What are these ? Could you create a version of the tool
that
> (again ?) incorporates this feature ?
>
> I will send you my updated version of this applet in a separate email.
>
> 3.
> Finally a question following up on the previous comment.
> Is it already possible, or would it be possible to add the capability
> to a future version, to use a set of selected points to define a filter?
>
> Thanks
>
> Gerard Lemson
>
>
> --
> * Gerard Lemson                       * Tel: +49 (0)89 30000-3316
> *
> * MPI fuer extraterrestische Physik   * Fax: +49 (0)89 30000-3569
> *
> * Giessenbachstrasse                  *
> *
> * Postfach 1312                       *
> *
> * D-85741 Garching, GERMANY           * email: gerard.lemson at mpe.mpg.de
> *
>