Allow setting minimum and maximum or fixed aspect ratio

[casey]

I'm not sure if this can be done in a cross-platform way, but it would nice to be able to set the minimum and maximum aspect ratio, or specify a fixed aspect ratio that the window must maintain.

Specifically, I'm writing some games/pixel rendering demos that operate at a specific pixel resolution, and it would be able to lock the window to the aspect ratio of the output.

[francesca64]

• X11
• macOS
• Windows

Overall, it doesn't look hard.

However, I must caution you: if you plan on having proper X11 support (and covering the other platforms not listed here), you must still handle cases where the window isn't the desired aspect ratio. There's a very good chance that tiling WMs (i3/etc.) won't respect this hint, though I haven't tested that to know for sure. Here's how to address that when using gfx-rs.

[casey]

I think that in addition to X11, macOS and windows will let you fullscreen a window with a locked aspect ratio, making it the size of the display and thus changing the aspect ratio.

[BartMassey]

Being able to control aspect ratio is pretty key for games and demos, including mine. I could supply an X11 implementation I think, but would want others to take other platforms. Is this something that winit would be interested in moving forward with?