Re: OS X help needed

[John W. Eaton]

On 10/27/2016 01:49 PM, Sebastian Schöps wrote:
> John W. Eaton wrote
> > We have the following code to get the number of bits per pixel for the
> > current display on OS X systems:
> >
> > [...]
> >
> > But now I see that the function CGDisplayModeCopyPixelEncoding has been
> > deprecated for OS X 10.11.  Is there a replacement?  It doesn't have to
> > be a direct replacement for this function, we just need some way to get
> > a value for the number of bits per pixel for the display.
> >
> > jwe
>
> I am not much help w.r.t. GUI programming but are you aware of the
> discussion at https://savannah.gnu.org/bugs/?49053 ? or let me ask
> differently: could one use qt for this?

Not really, as we still want to be able to get the info for the root 
figure object even if not using Qt.

But, just to see what Qt provides and how it works, I looked and there 
is the function

http://doc.qt.io/qt-4.8/qpaintdevice.html#metric

along with an enum value to get the display depth, as well as

http://doc.qt.io/qt-4.8/qpaintdevice.html#depth

to get the display depth directly (I think that's just a wrapper around 
the metric function).  Anyway, for OS X systems, Qt 4.8 simply returns 
32 unconditionally, and for Qt 5, it returns 24.

I suppose we could do the same if the functions to get the value from 
the OS are not available.

jwe