module_load_include not working
Assuming you want to load

sites/all/modules/custom/spower/polygon/polygonBase.php


then

module_load_include('php', 'spower', 'polygon/polygonBase');


should work fine.


Make sure the file polygonBase.php is readable by the webserver user.
Make sure module_load_include is added for processing prior to using functions in that file.