Custom ScaleMode class: can't modify FlxG.width / FlxG.height

[sebbernery]

Hello !
I tried to make a custom BaseScaleMode subclass to disable the scaling, but I can't modify FlxG.width and FlxG.height from my subclass of BaseScaleMode.

class MyScaleMode extends BaseScaleMode {
    override public function onMeasure(width:Int, height:Int) {
        FlxG.width = width;
        FlxG.height = height;
    }
} 

Gives me the error

[ERROR] src/PlayState.hx:18: characters 14-19

 18 |         FlxG.width = width;
    |              ^^^^^
    | This expression cannot be accessed for writing

[ERROR] src/PlayState.hx:19: characters 14-20

 19 |         FlxG.height = height;
    |              ^^^^^^
    | This expression cannot be accessed for writing

(Here is the error with Haxe 5 but I also have the error with Haxe 4).

The FlxG width / height fields are defined like this:

@:allow(flixel.system.scaleModes)
	public static var width(default, null):Int;

I can make a PR adding a method setFlxGWidth / setFlxGHeight in BaseScaleMode to allow this modification, is this a good solution for you ?

Have a nice day !

[Geokureli]

I think you're supposed to call super.onMeasure(width, height); which also calls various other important methods

[sebbernery]

super.onMeasure set FlxG.width to FlxG.initialWidth, it's not what I want.

The workaround I found for the moment is to extends from StageSizeScaleMode and call super.onMeasure because the onMeasure set FlxG.width to the Width parameter of the method. After that I correct the scaling like I want.

For the other attributes, I only set scale and offset because gameSize, deviceSize and vertical / horizontalAlign seems to never be used outside flixel.systems.scaleModes (Except for weird Reflect stuff, I only used grep to come to this conclusion). (Those attributes can be of course be useful to use the helpers in BaseScaleMode automatically setting scale and offset).

[Geokureli]

If this were me and this was something I needed a decent fix urgently for a personal project I would likely do this:

class MyScaleMode extends BaseScaleMode {
    @access(flixel.FlxG)
    override public function onMeasure(width:Int, height:Int) {
        FlxG.width = width;
        FlxG.height = height;
    }
} 

or

        @privateAccess FlxG.width = width;
        @privateAccess FlxG.height = height;

As for a long term fix, I think rather than setFlxGWidth and height, I would add setGlobalSize(w,h), since updateGameSize is taken and FlxG stands for "global", this isn't a perfect solution so I'm open to suggestions, but I do prefer this to "setFlxG" as the Flx is a prefix to avoid naming collisions