Glad I'm not the only one...
well, I did some more investigation. I get that slowdown too, and it
seems potentially related. the slowdown is happening in the call
im.resize(int(widthDisplay+0.5), int(heightDisplay+0.5),
norm=self._filternorm, radius=self._filterrad)
near line 162 in image.py
as you zoom, the time it takes to execute that line grows
exponentially. this is where it heads into compiled dll land as resize
is impemented in _image.cpp
see here:
http://matplotlib.svn.sourceforge.net/viewvc/matplotlib/trunk/matplotlib/src/_image.cpp?view=markup
I don't have a build setup for matplotlib, so I am holding off on doing
some printf investigations on _image.cpp, but perhaps this can help
track it down? Since it is independent of interpolation, shouldn't it
be something going on between lines 328 and 445 of _image.cpp?
t
Eric Firing wrote:
> I have verified this behavior briefly on a Linux machine. In
> addition, the redraw after zoom gets extremely slow. I have never
> worked with the image internals and I don't have any idea where the
> problem is coming from.
>
> Eric
>
> Tim Hirzel wrote:
>> To the fantastic matplotlib developers,
>> I am having a strange behavior when using zooming. I have tried it
>> with WX, Wxagg, and TKagg, and with Numeric and numpy. It occurs in
>> multiple interpolation types as well. The best way to see this
>> behavior is to use the image_interp.py example. If you zoom in
>> enough, the image starts to fade to white, and then turn completely
>> white. If you zoom in to about where the zoom the axes area spans
>> 0.1 units, it should still look fine, but then a span of 0.01 unit
>> will be all white. If you zoom in slowly to where the color is
>> starting to wash out to white, then resize the window, you will see
>> more strange whitening behavior (the color fluctuates between white
>> and the correct color as you change the window size). This is on a
>> windows machine with Python 2.4.
>> Another clue. if I save the white appearing axes to a png, it looks
>> fine.
>> the way it fades out almost seems like something going wrong with an
>> alpha value somewhere...
>> any thoughts?
>>
>> thanks,
>> Tim
>
>
-------------------------------------------------------------------------
Take Surveys. Earn Cash. Influence the Future of IT
Join SourceForge.net's Techsay panel and you'll get the chance to share your
opinions on IT & business topics through brief surveys - and earn cash
http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV
_______________________________________________
Matplotlib-devel mailing list
Matplotlib-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/matplotlib-devel
