public function getLayoutRootPath()
    {
        if ($this->layoutRootPath === null && $this->templatePathAndFilename === null) {
            throw new Exception\InvalidTemplateResourceException('No layout root path has been specified. Use setLayoutRootPath().', 1288091419);
        }
        if ($this->layoutRootPath === null) {
            $this->layoutRootPath = dirname($this->templatePathAndFilename) . '/Layouts';
        }
        return $this->layoutRootPath;
    }