sdl12-compat for macOS (was: Retina resolution support)
NOTE: Turns out the previous release can already use higher resolutions with old SDL in the same way that now works with sdl12-compat: Go to the screen setup, change resolution from "Desktop" to whatever you want, that choice will be respected.
Actually, these are four changes at once, with very limited impact on the source code.
Trigger was the final shutdown of altool
based notarizing services by Apple, and the new notarytool
required an operating system upgrade of the build virtual machine. It was on 10.14, and the new tool requires at least 10.15.
With that came an update to all libraries we use, naturally, including an update from old sdl12 to sdl12-compat, which uses SDL2 as backend, which is what enables the Retina support.
Unfortunately, the way sld12-compat loads SDL2 is not immediately understandable by the app bundle builder, so some changes to the bundling were required. That's the actual source change.
And finally, to properly activate Retina support, we default the SDL12COMPAT_HIGHDPI environment variable to 1. You can still set it to 0 from the outside and we will respect that.
Trunk builds had Retina support basically from the start, so no change there.