Classes/Service/Rendering.php
private function getTemplatePath()
    {
        /**
         * @var $tsfe TypoScriptFrontendController
         */
        $tsfe = $GLOBALS['TSFE'];
        if (isset($tsfe->tmpl->setup['lib.']['plugins.']['tx_happyfeet.']['view.']['template'])) {
            $templateFile = GeneralUtility::getFileAbsFileName(
                $tsfe->tmpl->setup['lib.']['plugins.']['tx_happyfeet.']['view.']['template']
            );
            if (is_file($templateFile)) {
                return $tsfe->tmpl->setup['lib.']['plugins.']['tx_happyfeet.']['view.']['template'];
            }
        }

        return $this->getTemplatePathAndFilename($this->defaultTemplate);
    }
private function getTemplatePath()
    {
        /**
         * @var $tsfe TypoScriptFrontendController
         */
        $tsfe = $GLOBALS['TSFE'];
        if (isset($tsfe->tmpl->setup['lib.']['plugins.']['tx_happyfeet.']['view.']['template'])) {
            $templateFile = GeneralUtility::getFileAbsFileName(
                $tsfe->tmpl->setup['lib.']['plugins.']['tx_happyfeet.']['view.']['template']
            );
            if (is_file($templateFile)) {
                return $tsfe->tmpl->setup['lib.']['plugins.']['tx_happyfeet.']['view.']['template'];
            }
        }

        return $this->getTemplatePathAndFilename($this->defaultTemplate);
    }
checks if a alternative template is defined via typoscript setup configuration and if it exists as a file

@return string