CGAL users discussion list

[Peter Hachenberger <>]

Hi Wonwoo,
 
 in general you don't have rounding problems in CGAL if you use an exakt Kernel. The points will be on the same plane, then.
 
 The main problem with your transformation is, that you put doubles into the matrix. Since you probably use a Homogeneous Kernel for the Nef polyhedra, the doubles are converted to integers. This means that every value between 0 and 1 is rounded to zero. Your matrix 
 looks the following:
 
 1, 0, 0, 200
 0, 0, 0, 200
 0, 0, 0, 200
 
 You see, that the Nef polyhedron collapses. Try to use the rational rotation as I told you in the last mail.
 
 Best, Peter