#ifndef SGVec2_H
#define SGVec2_H
-#if defined ( __CYGWIN__ )
-#include <ieeefp.h>
-#endif
-
#ifndef NO_OPENSCENEGRAPH_INTERFACE
#include <osg/Vec2f>
#include <osg/Vec2d>
template<typename S>
explicit SGVec2(const SGVec2<S>& d)
{ data()[0] = d[0]; data()[1] = d[1]; }
-#ifndef NO_OPENSCENEGRAPH_INTERFACE
- explicit SGVec2(const osg::Vec2f& d)
- { data()[0] = d[0]; data()[1] = d[1]; }
- explicit SGVec2(const osg::Vec2d& d)
- { data()[0] = d[0]; data()[1] = d[1]; }
-#endif
/// Access by index, the index is unchecked
const T& operator()(unsigned i) const
T (&data(void))[2]
{ return _data; }
-#ifndef NO_OPENSCENEGRAPH_INTERFACE
- osg::Vec2d osg() const
- { return osg::Vec2d(data()[0], data()[1]); }
-#endif
-
/// Inplace addition
SGVec2& operator+=(const SGVec2& v)
{ data()[0] += v(0); data()[1] += v(1); return *this; }
inline
SGVec2<T>
normalize(const SGVec2<T>& v)
-{ return (1/norm(v))*v; }
+{
+ T normv = norm(v);
+ if (normv <= SGLimits<T>::min())
+ return SGVec2<T>::zeros();
+ return (1/normv)*v;
+}
/// Return true if exactly the same
template<typename T>
distSqr(const SGVec2<T>& v1, const SGVec2<T>& v2)
{ SGVec2<T> tmp = v1 - v2; return dot(tmp, tmp); }
+// calculate the projection of u along the direction of d.
+template<typename T>
+inline
+SGVec2<T>
+projection(const SGVec2<T>& u, const SGVec2<T>& d)
+{
+ T denom = dot(d, d);
+ T ud = dot(u, d);
+ if (SGLimits<T>::min() < denom) return u;
+ else return d * (dot(u, d) / denom);
+}
+
#ifndef NDEBUG
template<typename T>
inline