OCCUtils provides convenience functions for computing the orthogonal direction to two directions:
#include <occutils/Axis.hxx> using namespace OCCUtils; gp_Ax1 axis = /* ... */; gp_Png point = /* ... */; bool pointIsOnAxis = Axis::Contains(axis, point);
In case you can’t use OCCUtils, here’s the code to do it manually:
gp_Lin(axis).Contains(pnt, Precision::Confusion());