CGAL::intersection

Object	intersection ( Type1<Kernel> obj1, Type2<Kernel> obj2)
		Two objects obj1 and obj2 intersect if there is a point p that is part of both obj1 and obj2. The intersection region of those two objects is defined as the set of all points p that are part of both obj1 and obj2. Note that for objects like triangles and polygons that enclose a bounded region, this region is considered part of the object. If a segment lies completely inside a triangle, then those two objects intersect and the intersection region is the complete segment.

The possible value for types Type1 and Type2 and the possible return values wrapped in Object are the following:

There is also an intersection function between 3 planes.

Object	intersection ( Plane_3<Kernel> pl1, Plane_3<Kernel> pl2, Plane_3<Kernel> pl3)
		returns the intersection of 3 planes, which can be either a point, a line, a plane, or empty.

Example

The following example demonstrates the most common use of intersection routines.

#include <CGAL/intersections.h>

void foo(CGAL::Segment_2<Kernel> seg, CGAL::Line_2<Kernel> line)
{
    CGAL::Object result;
    CGAL::Point_2<Kernel> ipoint;
    CGAL::Segment_2<Kernel> iseg;

    result = CGAL::intersection(seg, line);
    if (CGAL::assign(ipoint, result)) {

        // handle the point intersection case.

    } else
        if (CGAL::assign(iseg, result)) {

            // handle the segment intersection case.

        } else {

            // handle the no intersection case.
        }
}

See Also