concrete/src/File/Image/BasicThumbnailer.php
private function checkForThumbnailAndCreateIfNecessary($obj, $maxWidth, $maxHeight, $crop = false)
    {
        return $this->processThumbnail(false, $obj, $maxWidth, $maxHeight, $crop);
    }
private function checkForThumbnailAndCreateIfNecessary($obj, $maxWidth, $maxHeight, $crop = false)
    {
        return $this->processThumbnail(false, $obj, $maxWidth, $maxHeight, $crop);
    }
private function checkForThumbnailAndCreateIfNecessary ( $ obj , $ maxWidth , $ maxHeight , $ crop = false ) { return $ this -> processThumbnail ( false , $ obj , $ maxWidth , $ maxHeight , $ crop ) ; }
Checks filesystem for thumbnail and if file doesn't exist will create it immediately.
concrete5's default behavior from the beginning up to 8.1.

@param File|string $obj file instance of path to a file
@param int|null $maxWidth
@param int|null $maxHeight
@param bool $crop

@return \stdClass
Checks filesystem for thumbnail and if file doesn t exist will create it immediately . concrete5 s default behavior from the beginning up to 8 . 1 .