dflplot 0.01

[Eldar Insafutdinov]

When I saw David's announcement this morning, I remembered that he brought up this topic
sometime ago(about half-year I think) and I promised to have a look at wrapping Qwt (http://
qwt.sourceforge.net/) as a part of QtD after we make next release. We never released the next
version of QtD (as usual due to the lack of manpower and time), but we are still working on
it and hopefully we'll make it soon. I decided not to wait until the release, and try to wrap
Qwt with the development version of QtD. And it worked pretty well! I'm writing about it not
to belittle David's fantastic work, which was written from scratch and for sure deserves
admiration, but rather to do what I promised and I hope it will be useful.

So far I haven't ported all classes from the library, but the most difficult part of wrapping
is done, and binding the rest of the classes should be easy, which I will complete shortly. I
ported one of the Qwt examples from C++ to D to give a feel on how to use the binding, which
is available here: http://dsource.org/projects/qtd/browser/examples/qwt/simpleplot . Also,
screencapture of this little program in action: http://img13.imageshack.us/img13/6600/
simpleplot.png .

The binding is cross-platform, I tested it on Linux and Windows. For the latter, there are
pre-built packages which can be downloaded from http://dsource.org/projects/qtd/wiki/
Packages . For linux it should not be difficult to build them from sources, most of the
distributions contain Qwt. From what I read in the thread there is a problem with saving the
plots, which isn't solved yet. With Qt there are no such problems, any QWidget can be saved
to the pixmap object which you can manipulate as you wish.

There is at least one problem, the mentioned example crashes after you close the application.
This problem is known and has nothing to do with Qwt, it's a QtD bug, which is currently
being worked on and hopefully we'll resolve the issue.

This is just a result of my one-day experiment. Both dfl+dflplot and QtD+Qwt have their
advantages. dfl has nicer API(I must admit I never used it), dflplot has also more Dish feel,
while Qt and Qwt are more mature and I think more powerful. In the end, we are in the good
position, because we have a choice.