Undertale Yellow script viewer

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

}