Created attachment 1313 [details]
Test case demonstrating the issue when exiting fullscreen

In Mac OS X, when SDL_SetWindowFullscreen(window, 0) is called on a window which was in SDL_WINDOW_FULLSCREEN_DESKTOP mode, its original size is restored but its position is moved to the bottom of the screen.

I tracked down the issue to these two lines: http://hg.libsdl.org/SDL/file/66b5b8446275/src/video/cocoa/SDL_cocoawindow.m#l1034

I believe [nswindow setFrameOrigin:rect.origin] implicitly calls [nswindow constrainFrameRect:rect toScreen:screen], which will attempt to constrain the window to the screen, but at that point the window size is still full-screen rather than the restored window size, so the constrainFrameRect function operates on the wrong window size.

https://developer.apple.com/library/mac/documentation/cocoa/reference/applicationkit/classes/NSWindow_Class/Reference/Reference.html#//apple_ref/occ/instm/NSWindow/constrainFrameRect:toScreen:

I resolved the issue by swapping the order of the function calls, like so:
[nswindow setContentSize:rect.size];
[nswindow setFrameOrigin:rect.origin];

Alternatively I replaced the above two lines with this all-in-one function call, and it worked as well (I like this one better):
[nswindow setFrame:rect display:false];


I've attached some test code demonstrating the issue. You can press spacebar to toggle fullscreen-desktop mode.