[vtk-developers] Interactor freezing on OS X Cocoa

[Sean McBride]

On Mon, 23 Dec 2013 10:58:45 -0700, David Gobbi said:

>The Cocoa Event Handling Guide describes this "event filter" technique
>as the "The Mouse-Tracking Loop Approach" because the mouse
>essentially takes over the tracking loop until the drag is complete.
>It says explicitly that, in order to work well, there has to be some
>added logic to figure out whether filtered events are delayed or
>simply discarded.  Personally, I think it is just the wrong approach
>altogether.  On all other systems (X, Win32, Carbon) all events are
>simply passed through to VTK... no filtering is performed.  Would
>anyone object if I modified the Cocoa code so that it does the same?
>Having VTK receive the events out-of-order simply seems wrong.

I've always preferred what they call "The Three-Method Approach" myself.  I'm not sure why VTK is the way it is (it wasn't me that did that).  There may me some good reason we're not aware of.

I assume you're proposing we switch to the 'The Three-Method Approach' technique?  I'd be in favour of that, probably better do merge in after 6.1, as there are compatibility issues here.  (Since vtkCocoaGLView is a class users likely subclass, changing it will affect subclassers, and so we'd need to document this well, etc.)

Also, I fear your work will conflict with this:
<http://review.source.kitware.com/#/c/12200/>

Which I guess I should have gotten around to merging in! :) Perhaps you could branch your work off that?  Or maybe it's ready to merge before 6.1....

Cheers,

-- 
____________________________________________________________
Sean McBride, B. Eng                 sean at rogue-research.com
Rogue Research                        www.rogue-research.com 
Mac Software Developer              Montréal, Québec, Canada