In the game that I will be planning to make, it will use Layouts and a few other things and I would like to make it so that the window can be no smaller than 320x240.

Is it possible to do this?

By this I mean, when you drag a corner of a window to re-size it, the window will stop becoming smaller when it hits a certain threshold.

I'm aware of al_resize_display() but I was wondering if there was a way to prevent the window from resizing in the first place.

Thanks

I'd like it as well. I'll do the X11 version of it if someone makes the Windows version. Since we have al_set_new_window_position already, I guess a function similar to that would fit well into the API.

I half expected you could implement this yourself by just not acknowledging resizes once it gets too small or large..

The window is still resized, even if you don't acknowledge it.

There needs to be a function al_set_window_constraints(display, minw, minh, maxw, maxh). It doesn't need to affect explicit resizes.

(Edit: maybe even an optional ratio parameter... Not sure what is easily supported by the underlying OS.)

That doesn't really work very well with events.

Plus, you need to have the ability to clamp to the constraints. If the minimum width is 300, you wouldn't want an attempt to resize to 295 to be ignored completely... you'd want it to clamp to 300.

Turns out this is dead easy in Windows:

In the message loop, just handle the:

WM_GETMINMAXINFO

message

and just fill out the MINMAXINFO structure.

http://msdn.microsoft.com/en-us/library/ms632626%28v=vs.85%29.aspx

That's odd. I expected it to give you a "Begin Resize" event that you can ignore, or call a function, or return a special variable to cancel the resize (or clamp it).

It's not that hard to do the math, just fetch the non-client border size, and combine it with the numbers specified by the user with the new function.

Well, ok, you do get viewWillStartLiveResize`/`viewDidEndLiveResize, but you can't cancel the resize.

Yes. I didn't mean to imply it'd be in any way difficult.

As long as it can be done without breaking Binary Compatibility, it could be added to 5.0.x

Yeah, it wouldn't be that hard to support.

What do you mean?
Allegro generates a "display resized" message when it receives a "resize done" message.

On OS X, I think there's a flag that controls the behaviour of the window while it resizes. Not sure though, but it would make sense. Would then also make sense to have the same on other platforms.

In X11 it's up to the window manager how to resize. E.g. in compiz I can set it to only show a transparent rectangle while resizing then send a single resize message to the application when I let go, or I can set it to stretch, or to constantly send 100ds of messages to the application during the resize. The application itself doesn't know which way is being used (at least not by default, possibly there's a way to override it somehow).

Anyway, I agree that the Windows behavior should be changed and if we can have three events for resize_start, resize_in_progress and resize_done (or a flag in the ALLEGRO_EVENT_DISPLAY_RESIZED event indicating which of the three it is), all the better.