bp_ps_Fields::set_display( $f,  $filter )

	public static function set_display ($f, $filter)
	{
		$format = isset ($f->format)? $f->format: 'none';
		$enum = (isset ($f->options) && is_array ($f->options))? count ($f->options): 0;
		$selector = $format. ($enum? '/e': '');
		if (!isset (self::$display[$selector][$filter]))  return false;

		$display = self::$display[$selector][$filter];
		if (is_string ($display))
		{
			$f->display = $display;
		}
		else
		{
			$default = (isset ($f->type) && in_array ($f->type, $display))? $f->type: $display[0];
			$choice = apply_filters ('bp_ps_field_display', $default, $f);
			$f->display = in_array ($choice, $display)? $choice: $default;
		}
		return true;
	}