Re: [Matplotlib-users] ANN: matplotlib-0.90.0

[Christopher B. <Chr...@no...>]

Werner F. Bruhin wrote:
> Great to see a new release, will put some time aside to test it with 
> wxPython early next week.

looking forward to your reports.

> which versions of wxPython are supported?

I haven't tried the new one, but the last release worked well with 
wxPython2.6.3, but had some issues with 2.8.* -- I don't think anyone 
has addressed those yet.

> Well, we haven't built any binaries yet.  We pushed a source release
> fast to try to get it into Feisty.  Sorry Chris!

well, I've been chattering on about this for awhile, but haven't 
contributed anything yet...

 > With wx2.8 out now
> and this being a major release, we definitely need to rethink wx
> builds.  We stuck with unicode for 0.87 to avoid confusion.  I would
> be happy to hear what wx users think/want.

I think it's time to just all unicode, all the way, but I mostly deal 
with English anyway.

> For me the ideal would be not to be depended on a particular release of 
> wxPython - big surprise no :-)

That would be nice.

> If I understand it correctly the dependency came in for performance 
> optimization, does 2.8 change something for this.

Perhaps. 2.8 has methods for directly setting the data in wxBitmaps. 
Before that, you needed to create a wxImage, then convert that to a bitmap.

However, to do that right, you'd need to be able to get the Agg bitmap 
as a Python buffer object that is in the binary form required by the 
platform. I think the majors need RGB and/or RGBA, but I'm not totally 
sure about that (maybe OS-X is ARGB?)

> - If yes, I would not see a problem with 0.9 requiring as a minimum 
> 2.8.0.1 but going forward I could use any 2.8.x or newer release.

That would be a good way to go, or have fallback on the older methods 
for less than 2.8 -- so instead of saying "you need 2.8 to use the wx 
backend" we can say: "you'll get better performance with wx if you use > 
2.8"

> - If no, then I guess we have to live with having a "fixed" dependency, 
> e.g. 0.87 is wxPython 2.6.x, 0.90 is wxPython 2.8.x, but it should 
> through at least a warning if one tries to use it with another wxPython 
> release.

Yes, it should. I've also started a patch for the build system that 
tries harder to make sure that you are building against the same wx that 
you are running -- that will at least help people built it themselves 
more easily.

NOTE: I took a look at the wx backend code a while ago, and it looks 
like even without the new Bitmap handlers in 2.8, it could be faster 
with straight Python code. Key is that a wxImage can be created from a 
Python buffer object without copying the data. So if we can expose the 
Agg buffer as a Python buffer, as RGB, then we should be able to get 
decent performance with pure python. You'd still need to do the 
wxBitmapFromImage thing, but the accelerated back-end does that too.

Look for a thread on this list a while back, with my and Ken's name on it.

-Chris



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