[SDL] Re: Mouse position bugs on Mac OS X

Christian Walther cwalther at gmx.ch
Mon Nov 21 08:26:07 PST 2005

E. Wing wrote:
>>2. When using OpenGL, SDL_WarpMouse() inverts the y coordinate.
> The mouse inversion problem for windowed-OpenGL appeared going from
> Jaguar to Panther. I don't remember if we ever resolved this in an
> elegant way.

Currently, there is an inversion in QZ_PrivateCocoaToSDL(), which makes 
getting mouse coordinates work correctly (apart from the off-by-one 
bug). The bug is that the same inversion is also needed in 
QZ_PrivateSDLToCocoa(), which is used when setting mouse coordinates, 
i.e. SDL_WarpMouse(). My patch fixes that.

> At one point I thought I did, but I remembered I ended up
> breaking more stuff and I can't remember if I fixed this or went to an
> OS version check to case the two different situations.

There is no version check in the latest code, and according to your last 
changelog entry 
it works everywhere. And if that's true, I guess my patch should also be 
correct everywhere, but I'll still test it to be sure.

> So be careful about testing this one between the Jaguar/Panther
> barrier. If not done correctly, it will probably (incorrectly) invert
> pre-10.3 systems. I would also advise testing the non-OpenGL modes and
> maybe even the fullscreen modes.

Yup, my test program does all combinations of GL/non-GL and 
windowed/fullscreen, and I intend to test it at least on 10.2 and maybe 
10.1. I already did on 10.4.0, and behavior there is identical to 10.3.9.


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