* Added a new API function to test if a GPencil layer is visible or not * Replaced all editability checks with this new "super check" * Replaced all magic number thresholds for opacity visiblity with a single define
* Added a new API function to test if a GPencil layer is visible or not * Replaced all editability checks with this new "super check" * Replaced all magic number thresholds for opacity visiblity with a single define