function __background_set_internal(arg0, arg1, arg2, arg3)
{
    var __prop = arg0;
    var __bind = arg1;
    var __val = arg2;
    var __backinfo = arg3;
    if (__backinfo[0] == -1)
        return -1;
    var __backid = __backinfo[0];
    var __layerid = __backinfo[1];
    var __isfore = __backinfo[2];
    if (__prop == e__BG.Foreground)
    {
        if (round(__val) != round(__isfore))
        {
            var __visible = layer_get_visible(__layerid);
            var __index = layer_background_get_sprite(__backid);
            var __htiled = layer_background_get_htiled(__backid);
            var __vtiled = layer_background_get_vtiled(__backid);
            var __stretch = layer_background_get_stretch(__backid);
            var __blend = layer_background_get_blend(__backid);
            var __alpha = layer_background_get_alpha(__backid);
            var __xscale = layer_background_get_xscale(__backid);
            var __yscale = layer_background_get_yscale(__backid);
            var __x = layer_get_x(__layerid);
            var __y = layer_get_y(__layerid);
            var __hspeed = layer_get_hspeed(__layerid);
            var __vspeed = layer_get_vspeed(__layerid);
            __background_set_element(__bind, __visible, __val, __index, __x, __y, __htiled, __vtiled, __xscale, __yscale, __stretch, __hspeed, __vspeed, __blend, __alpha);
        }
    }
    else
    {
        switch (__prop)
        {
            case e__BG.Visible:
                layer_set_visible(__layerid, __val);
                layer_background_visible(__backid, __val);
                break;
            case e__BG.Index:
                layer_background_change(__backid, __val);
                if (sprite_exists(__val))
                {
                    layer_background_blend(__backid, c_white);
                    layer_background_alpha(__backid, 1);
                }
                break;
            case e__BG.X:
                layer_x(__layerid, __val);
                break;
            case e__BG.Y:
                layer_y(__layerid, __val);
                break;
            case e__BG.HTiled:
                layer_background_htiled(__backid, __val);
                break;
            case e__BG.VTiled:
                layer_background_vtiled(__backid, __val);
                break;
            case e__BG.XScale:
                layer_background_xscale(__backid, __val);
                break;
            case e__BG.YScale:
                layer_background_yscale(__backid, __val);
                break;
            case e__BG.HSpeed:
                layer_hspeed(__layerid, __val);
                break;
            case e__BG.VSpeed:
                layer_vspeed(__layerid, __val);
                break;
            case e__BG.Blend:
                layer_background_blend(__backid, __val);
                break;
            case e__BG.Alpha:
                layer_background_alpha(__backid, __val);
                break;
            default:
                break;
        }
    }
    return -1;
}

enum e__BG
{
    Visible,
    Foreground,
    Index,
    X,
    Y,
    Width,
    Height,
    HTiled,
    VTiled,
    XScale,
    YScale,
    HSpeed,
    VSpeed,
    Blend,
    Alpha
}