qt4backend zoom-to-rect box is drawn incorrectly on OSX

[efiring]

Only on OSX:

import matplotlib
matplotlib.use("qt4agg")
import matplotlib.pyplot as plt
plt.plot([1,2,3])
plt.show()

Now click zoom-to-rect; instead of a solid rectangle outline, I get a dotted L-shape.

This is with mpl v1.2.x, 7f5b005, pyqt 4.9.4 from homebrew, OS X 10.8.

[dmcdougall]

I can't recreate this. I'm on OS X 10.7 with pyqt4 4.9.4 using current master: 3bee65c.

[dmcdougall]

Update: I can't recreate it even with the same commit as yours: 7f5b005.

[efiring]

@dmcdougall It looks like this may be a problem with OS X 10.8 then, and/or specifically on machines with the retina display. Or qt version. I was on 4.8.2; now I am downloading and building 4.8.3. It will take some time...

[dmcdougall]

I'm using Qt 4.8.3.

The retina display seems like a very likely candidate, given that the edges of the rectangle could technically lie on 'subpixels'. Have you tried making several zoom rectangles? And dragging in every direction? Are there any circumstances where you can get a square and not an 'L'?

[dmcdougall]

@efiring Sorry, I misread your initial bug report. I get a dotted zoom rectangle, not a solid rectangle. However, I do not get an 'L'.

[efiring]

So far, in today's testing, I have never gotten the rectangle, only the L. I only noticed this today, and I only updated to 10.8 a few days ago, so I suspect it is the 10.7->10.8 change that did it.

[efiring]

Now with qt4.8.3 and recompiled pyqt: no change, still a dotted-L, always with the apex in the lower left.

I don't think this is anything likely to be dealt with at the mpl level. Fortunately, it is fairly minor.

[dmcdougall]

Thanks for confirming. I wonder if any of the other mac people on 10.8 without retina displays see the 'L'.

I'm surprised it didn't take you long to compile qt4. It takes me several hours...

[efiring]

I did a "brew upgrade", which seems to have unpacked a pre-compiled tarball.

[dmcdougall]

I use MacPorts, though they have recently started unpacking pre-compiled tarballs as well. It is now far less painful than it used to be.

[tacaswell]

@efiring @dmcdougall Has this been magically fixed?

[efiring]

@tacaswell, the problem persists on OSX 10.8. I haven't tried 10.9.

[tacaswell]

@efiring Did the qt5 related refactor and/or general system upgrades magically fix this?

[efiring]

I don't see it now with 1.4.3 or 1.5.x using anaconda, on the same machine as before, but with OSX 10.9 rather than 10.8. So something fixed it.