execute Snippet if a TV is not empty - right approach?

<?php
$photos = $modx->getTemplateVar('photos');
if (!empty($photos['value'])) {
         $SnippetCall = '{{SnippetCall}}';
         return $SnippetCall;
}
return;
?>

<?php
$photos = $modx->getTemplateVar('photos');
if (!empty($photos['value'])) {
    return $modx->runSnippet('your-snippet-name', array('param_1' => $value1, 'param_2' => $value2, ...));
}
?>

<?php
$LatLng = $modx->getTemplateVar('mkrLatLng');
$KML = $modx->getTemplateVar('KML');
if (empty($LatLng['value']) && empty($KML['value'])) {
         return '';
}
?>

$modx->resource﷓>getTVValue('TvName');

$modx->resource﷓>getTVValue($id); /*  where $id is the ID of the TV -- faster */