Jae-Joon Lee wrote: > I think it is a good idea to add such a feature in mpl, and I guess it > would better to have some general way to provide backend specific > options. > Also note that this specific functionality isn't backend-specific. PDF files, for example, also have the ability to have clickable links. So any design we come up with should be seen as "general functionality which only some backends implement when the format supports it" rather than a "backend-specific hack". In this case, simply ignoring the url is a reasonable thing to do for backends that can't support it. > Actually, I have been using a modified version of mpl which enables to > set the individual ID of the patches (this is only meaningful in case > of the svg backend) in a very similar way that Andrew described. The > purpose of setting ID is to do some postprocessing of the resulting > svg file. A small post about this can be found at > > http://abitofpythonabitofastronomy.blogspot.com/2008/10/svg.html > This is a very cool example -- and presents another great feature to add in the future (filtering). Again, it's conceivable that future versions of PDF may have similar functionality, so we should think about generic ways to do it. But that's probably another discussion... > And my approach was also to use GCs. Although I don't quite like this > approach, it seems to be the easiest way because, as far as I know, > the backends in mpl does not know about the artists. > You're right, the high-level artists that are exposed to the end user of matplotlib are somewhat removed from the low-level graphics primitives that are passed to the backends, and that may be problematic. But adding this to the GC of an artist is the cleanest way I can think of to add these extra properties that need to be passed to the backends, as we wouldn't have to change the backend API.
Since the creation of the gc for each drawing call happens mainly in base classes (Patch, Text, Collection), there shouldn't be too many places to update to add these extra attributes to the gc. We could handle these new attributes in Artist.draw and have Patch.draw, Text.draw, Collection.draw etc. delegate to that to reduce code duplication. > I think we may introduce a new dictionary property to the GC class and > also in the Artist. And modifies draw() methods of Patch and others so > that it use these properties to pass any optioanl information ( > "url"or "id") to the backends. > Are you suggesting an extra dictionary in the gc to which arbitrary key/value pairs can be added? I don't like that very much. I think if we're going to support hyperlinks, we should create a true API for them that could be used across all backends (even if most backends can't support the functionality). > But I'm not sure is if it is a good idea to expose this option (or > "url" in the Andrew's original post) to the functions in the axes.py. > We can just grab the return value of the "bar" command (which is a > list of patches) and set some backend specific options for each > patches. > For the same reasons above, I don't see this as backend-specific, so I don't have a problem adding it as an Artist setter/kwarg that would be available on any method where Artist kwargs are supported. (And probably analogously have a list of urls for Collections). In the specific case of bar(), one may still be forced to manually set urls on each Rectangle if one wants those urls to be different. But this is no different than the current situation wrt facecolor or any other attribute, since bar is not written on top of Collection. Anyway, I like where this is going. I think this will be a great addition. Cheers, Mike > > On Wed, Oct 29, 2008 at 6:06 PM, Andrew Stock > <[EMAIL PROTECTED]> wrote: > >> Hi, >> >> I have a requirement to make clickable bar charts using the SVG output >> (rather than html maps). >> >> An initial look has suggested that the following changes would be required: >> >> backend_bases.py: Add a url property to GraphicsContextBase >> (defaulting to None, so it's all backwards compatible) >> axes.py: Add a url option to the bar function and pass this on to the >> constructor of the Rectangle object >> patches.py: Pass the url option in the constructor for the Patch >> object to the GraphicsContextBase object created in the draw function >> backends/backend_svg.py: Add check to _draw_svg_element for url set in >> gc. If it is, write out SVG code for xlink. >> >> I can make these changes and (if people think it would be useful) >> contribute the changes back. However, before I do this, I wanted to >> check whether this is the right approach to take - I'm not experienced >> with the internals of matplotlib and so if there's a better way of >> doing it, I'd be grateful for the advice. >> >> Once I got the bar charts working, I would be interested in possibly >> extending this to other chart types. >> >> Regards >> >> Andrew >> >> ------------------------------------------------------------------------- >> This SF.Net email is sponsored by the Moblin Your Move Developer's challenge >> Build the coolest Linux based applications with Moblin SDK & win great prizes >> Grand prize is a trip for two to an Open Source event anywhere in the world >> http://moblin-contest.org/redirect.php?banner_id=100&url=/ >> _______________________________________________ >> Matplotlib-devel mailing list >> Matplotlib-devel@lists.sourceforge.net >> https://lists.sourceforge.net/lists/listinfo/matplotlib-devel >> >> > > ------------------------------------------------------------------------- > This SF.Net email is sponsored by the Moblin Your Move Developer's challenge > Build the coolest Linux based applications with Moblin SDK & win great prizes > Grand prize is a trip for two to an Open Source event anywhere in the world > http://moblin-contest.org/redirect.php?banner_id=100&url=/ > _______________________________________________ > Matplotlib-devel mailing list > Matplotlib-devel@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/matplotlib-devel > -- Michael Droettboom Science Software Branch Operations and Engineering Division Space Telescope Science Institute Operated by AURA for NASA ------------------------------------------------------------------------- This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK & win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100&url=/ _______________________________________________ Matplotlib-devel mailing list Matplotlib-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-devel
