SoBoolOperation(3) on Linux
The text 1fe5b6b14238, as Debian 4.0 (Etch) shipped it.
The SoBoolOperation engine evaluates expressions of boolean logic. The multivalue fields SoBoolOperation::a and SoBoolOperation::b are combined according to the operations set in SoBoolOperation::operation, with the resulting TRUE or FALSE value set on SoBoolOperation::output.