The following describes map options. Example:
$default_map = array(
'options' => array(
'displayProjection' => '4326',
'maxResolution' => 156543.0339,
'maxExtent' => array(
'left' => -20037508.34,
'bottom' => -20037508.34,
'right' => 20037508.34,
'top' => 20037508.34,
),
'fractionalZoom' => ??
),
);
array( 'left' => -20037508.34, 'bottom' => -20037508.34, 'right' => 20037508.34, 'top' => 20037508.34, ),