function scr_selfshadow(arg0 = x, arg1 = y, arg2 = image_xscale)
{
    if (i_ex(obj_sunshadows))
    {
        if (obj_sunshadows.evening_mode && !selfshadow_override)
        {
            var _sprname = sprite_get_name(sprite_index);
            var _cache = obj_sunshadows.shadow_assetcache;
            var _sprite_cached = variable_struct_get(_cache, _sprname);
            var _finalsprite;
            if (is_undefined(_sprite_cached) || is_undefined(variable_struct_get(_sprite_cached, "selfshadow")))
            {
                var _spritelookup = asset_get_index(sprite_get_name(sprite_index) + "_shadow");
                if (is_undefined(_sprite_cached))
                {
                    variable_struct_set(_cache, _sprname, 
                    {
                        selfshadow: _spritelookup
                    });
                }
                else
                {
                    variable_struct_get(_cache, _sprname).selfshadow = _spritelookup;
                }
                _finalsprite = _spritelookup;
            }
            else
            {
                _finalsprite = _sprite_cached.selfshadow;
            }
            shader_replace_simple_set_hook(25);
            with (obj_sunshadows)
                shader_set_uniform_f(u_shadowblend, shadowblend_r, shadowblend_g, shadowblend_b, alpha_shadowblend);
            if (_finalsprite != -1)
                draw_sprite_ext(_finalsprite, image_index, arg0, arg1, image_xscale, image_yscale, image_angle, image_blend, image_alpha);
            shader_replace_simple_reset_hook();
        }
        else
        {
            shader_replace_simple_set_hook(25);
            with (obj_sunshadows)
                shader_set_uniform_f(u_shadowblend, shadowblend_r, shadowblend_g, shadowblend_b, alpha_shadowblend);
            draw_sprite_ext(sprite_index, image_index, arg0, arg1, image_xscale, image_yscale, image_angle, image_blend, image_alpha);
            shader_replace_simple_reset_hook();
        }
    }
}

function scr_addtoselfshadows(arg0 = true, arg1 = id, arg2 = false, arg3 = false)
{
    selfshadow_override = false;
    with (obj_sunshadows)
        array_push(selfshadow_instances, arg1);
    if (arg2)
    {
        with (obj_sunshadows)
            array_push(dropshadow_instances, arg1);
    }
    if (arg3)
    {
        with (obj_sunshadows)
            array_push(highlight_instances, arg1);
    }
    if (arg0)
    {
        draw_func = method(id, function()
        {
            draw_self();
            scr_selfshadow();
        });
    }
}