Irrlicht Engine

The branch is executed when rotationFromTo is called with to vectors, pointing in opposing directions. In that case, a 180 degree rotation about a vector perpendicular to one of the two vectors is required. The original code would take the cross product of a unit vector pointing down either the x or...

In the download-able version 1.7.2 and SVN revision 3702, the file quaternion.h contains a very interesting passage in the function "rotationFromTo", namely lines 633-638(651-656 in SVN):   axis = axis.crossProduct(core::vector3df(X,Y,Z)); if (axis.getLength()==0) {     axis.set(0.f,1.f,0....