HaxePunk/HaxePunk

package haxepunk.screen;

@:enum
abstract UniformScaleType(Int)
{
    /**
     * When the screen ratio changes, zoom in (show less of the game.)
     */
    var ZoomIn = 0;
    /**
     * When the screen ratio changes, zoom out (show more of the game.)
     */
    var Expand = 1;
    /**
     * When the screen ratio changes, zoom out and hide the overflow behind
     * black bars.
     */
    var Letterbox = 2;
}

/**
 * ScaleMode that ensures scaleX = scaleY.
 * @since    2.6.0
 */
class UniformScaleMode extends ScaleMode
{
    var type:UniformScaleType;

    /**
     * @param    integer        Whether scale should be rounded to an integer.
     * @param    mode
     */
    public function new(type:UniformScaleType = Expand, integer:Bool = false)
    {
        super(integer);
        this.type = type;
    }

    override public function resize(stageWidth:Int, stageHeight:Int)
    {
        var scaleX = stageWidth / baseWidth,
            scaleY = stageHeight / baseHeight;
        var zoomIn = type == ZoomIn,
            expand = type == Expand;
        var scale = zoomIn ? Math.max(scaleX, scaleY) : Math.min(scaleX, scaleY);
        if (integer)
        {
            scale = Std.int(zoomIn ? Math.ceil(scale) : Math.floor(scale));
            if (scale < 1) scale = 1;
        }

        HXP.screen.scaleX = HXP.screen.scaleY = scale;
        switch (type)
        {
            case Letterbox:
                // fill only part of the window
                HXP.screen.width = Std.int(baseWidth * scale);
                HXP.screen.height = Std.int(baseHeight * scale);
                HXP.screen.x = Std.int((stageWidth - HXP.screen.width) / 2);
                HXP.screen.y = Std.int((stageHeight - HXP.screen.height) / 2);
            case Expand, ZoomIn:
                // fill the window
                HXP.screen.x = HXP.screen.y = 0;
                HXP.screen.width = stageWidth;
                HXP.screen.height = stageHeight;
        }
    }
}