I've been continuing work on the OSX retina display support (started here), and I think I'm basically done.

Could somebody with OSX try and compile by experimental branch and see how well it works? The branch is here: https://github.com/SiegeLord/allegro5/tree/osx_retina. The two good examples to try are ex_resize2 and ex_fs_window. The first should resize and go into fullscreen ok without issues (aside from an occasional known crash). In all cases, the mysha image should fill the entire window. The second should enter/leave fullscreen mode and programmatically resize when you press space and enter buttons without any issues (but please report if there is a menu bar on the top of the screen when in fullscreen mode).

The way this feature is implemented right now is as follows:

• When you request a display with a width and height, those are specified in pixels and not in points like they currently are in 5.0/5.1.

• When you create a resizable display and drag it between two monitors with different DPIs, the display will maintain its size in points and send you a resize event during the transition.

• A non-resizable display in the above scenario will maintain its size in pixels (and will appear to shrink when dragged from a low DPI display to a high DPI display).

• All of the above behavior needs to be enabled by setting NSHighResolutionCapable inside your bundled app's Info.plist (for a 'console' app, the above behavior is the default).

Thanks!

Thomas actually graciosly let me VNC into his Mac Mini server, so I could test this for real. Everything worked just fine, so I'm going to be merging this pretty soon.