TCA::setConfig() 

\nn\t3::TCA()->setConfig($path = '', $override = []); 

Overwrite a configuration of the TCA, e.g. to overwrite a mask field with its own renderType or to change core settings in the TCA on the pages or tt_content tables.

The following example sets/overwrites the config array in the TCA under:

$GLOBALS['TCA']['tt_content']['columns']['mycol']['config'][...]

\nn\t3::TCA()->setConfig('tt_content.columns.mycol', [
    'renderType' => 'nnsiteIconCollection',
    'iconconfig' => 'tx_nnsite.iconcollection',
]);

See also \nn\t3::TCA()->setContentConfig() for a short version of this method when it comes to the table tt_content and \nn\t3::TCA()->setPagesConfig() for the table pages

| @return array

public function setConfig( $path = '', $override = [] )
{
	if ($config = &$this->getConfig( $path )) {
		$config = \nn\t3::Arrays()->merge( $config, $override );
	}
	return $config;
}