X-Git-Url: https://git.mxchange.org/?a=blobdiff_plain;f=simgear%2Fmath%2FSGVec3.hxx;h=56775d3ede34ba6affc15d8fa37076c684311875;hb=66c9187c95fb6861d9737f135fdf68d1bfa265f3;hp=afe7049d80e125038e9096d55b41c62e1ea13058;hpb=9be14a63b1b593b02b5cc3e82edb7a266ae3cbe7;p=simgear.git

diff --git a/simgear/math/SGVec3.hxx b/simgear/math/SGVec3.hxx
index afe7049d..56775d3e 100644
--- a/simgear/math/SGVec3.hxx
+++ b/simgear/math/SGVec3.hxx
@@ -1,4 +1,4 @@
-// Copyright (C) 2006  Mathias Froehlich - Mathias.Froehlich@web.de
+// Copyright (C) 2006-2009  Mathias Froehlich - Mathias.Froehlich@web.de
 //
 // This library is free software; you can redistribute it and/or
 // modify it under the terms of the GNU Library General Public
@@ -10,10 +10,9 @@
 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 // Library General Public License for more details.
 //
-// You should have received a copy of the GNU Library General Public
-// License along with this library; if not, write to the
-// Free Software Foundation, Inc., 59 Temple Place - Suite 330,
-// Boston, MA  02111-1307, USA.
+// You should have received a copy of the GNU General Public License
+// along with this program; if not, write to the Free Software
+// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 //
 
 #ifndef SGVec3_H
@@ -25,6 +24,11 @@ class SGVec3 {
 public:
   typedef T value_type;
 
+#ifdef __GNUC__
+// Avoid "_data not initialized" warnings (see comment below).
+#   pragma GCC diagnostic ignored "-Wuninitialized"
+#endif
+
   /// Default constructor. Does not initialize at all.
   /// If you need them zero initialized, use SGVec3::zeros()
   SGVec3(void)
@@ -34,82 +38,78 @@ public:
     /// uninitialized values in the debug build very fast ...
 #ifndef NDEBUG
     for (unsigned i = 0; i < 3; ++i)
-      _data[i] = SGLimits<T>::quiet_NaN();
+      data()[i] = SGLimits<T>::quiet_NaN();
 #endif
   }
+
+#ifdef __GNUC__
+  // Restore warning settings.
+#   pragma GCC diagnostic warning "-Wuninitialized"
+#endif
+
   /// Constructor. Initialize by the given values
   SGVec3(T x, T y, T z)
-  { _data[0] = x; _data[1] = y; _data[2] = z; }
+  { data()[0] = x; data()[1] = y; data()[2] = z; }
   /// Constructor. Initialize by the content of a plain array,
   /// make sure it has at least 3 elements
-  explicit SGVec3(const T* data)
-  { _data[0] = data[0]; _data[1] = data[1]; _data[2] = data[2]; }
-  /// Constructor. Initialize by a geodetic coordinate
-  /// Note that this conversion is relatively expensive to compute
-  SGVec3(const SGGeod& geod)
-  { SGGeodesy::SGGeodToCart(geod, *this); }
-  /// Constructor. Initialize by a geocentric coordinate
-  /// Note that this conversion is relatively expensive to compute
-  SGVec3(const SGGeoc& geoc)
-  { SGGeodesy::SGGeocToCart(geoc, *this); }
+  explicit SGVec3(const T* d)
+  { data()[0] = d[0]; data()[1] = d[1]; data()[2] = d[2]; }
+  template<typename S>
+  explicit SGVec3(const SGVec3<S>& d)
+  { data()[0] = d[0]; data()[1] = d[1]; data()[2] = d[2]; }
+  explicit SGVec3(const SGVec2<T>& v2, const T& v3 = 0)
+  { data()[0] = v2[0]; data()[1] = v2[1]; data()[2] = v3; }
 
   /// Access by index, the index is unchecked
   const T& operator()(unsigned i) const
-  { return _data[i]; }
+  { return data()[i]; }
   /// Access by index, the index is unchecked
   T& operator()(unsigned i)
-  { return _data[i]; }
+  { return data()[i]; }
 
   /// Access raw data by index, the index is unchecked
   const T& operator[](unsigned i) const
-  { return _data[i]; }
+  { return data()[i]; }
   /// Access raw data by index, the index is unchecked
   T& operator[](unsigned i)
-  { return _data[i]; }
+  { return data()[i]; }
 
   /// Access the x component
   const T& x(void) const
-  { return _data[0]; }
+  { return data()[0]; }
   /// Access the x component
   T& x(void)
-  { return _data[0]; }
+  { return data()[0]; }
   /// Access the y component
   const T& y(void) const
-  { return _data[1]; }
+  { return data()[1]; }
   /// Access the y component
   T& y(void)
-  { return _data[1]; }
+  { return data()[1]; }
   /// Access the z component
   const T& z(void) const
-  { return _data[2]; }
+  { return data()[2]; }
   /// Access the z component
   T& z(void)
-  { return _data[2]; }
+  { return data()[2]; }
 
-  /// Get the data pointer
-  const T* data(void) const
+  /// Readonly raw storage interface
+  const T (&data(void) const)[3]
   { return _data; }
-  /// Get the data pointer
-  T* data(void)
-  { return _data; }
-
-  /// Readonly interface function to ssg's sgVec3/sgdVec3
-  const T (&sg(void) const)[3]
-  { return _data; }
-  /// Interface function to ssg's sgVec3/sgdVec3
-  T (&sg(void))[3]
+  /// Readonly raw storage interface
+  T (&data(void))[3]
   { return _data; }
 
   /// Inplace addition
   SGVec3& operator+=(const SGVec3& v)
-  { _data[0] += v(0); _data[1] += v(1); _data[2] += v(2); return *this; }
+  { data()[0] += v(0); data()[1] += v(1); data()[2] += v(2); return *this; }
   /// Inplace subtraction
   SGVec3& operator-=(const SGVec3& v)
-  { _data[0] -= v(0); _data[1] -= v(1); _data[2] -= v(2); return *this; }
+  { data()[0] -= v(0); data()[1] -= v(1); data()[2] -= v(2); return *this; }
   /// Inplace scalar multiplication
   template<typename S>
   SGVec3& operator*=(S s)
-  { _data[0] *= s; _data[1] *= s; _data[2] *= s; return *this; }
+  { data()[0] *= s; data()[1] *= s; data()[2] *= s; return *this; }
   /// Inplace scalar multiplication by 1/s
   template<typename S>
   SGVec3& operator/=(S s)
@@ -126,11 +126,57 @@ public:
   static SGVec3 e3(void)
   { return SGVec3(0, 0, 1); }
 
+  /// Constructor. Initialize by a geodetic coordinate
+  /// Note that this conversion is relatively expensive to compute
+  static SGVec3 fromGeod(const SGGeod& geod);
+  /// Constructor. Initialize by a geocentric coordinate
+  /// Note that this conversion is relatively expensive to compute
+  static SGVec3 fromGeoc(const SGGeoc& geoc);
+
 private:
-  /// The actual data
   T _data[3];
 };
 
+template<>
+inline
+SGVec3<double>
+SGVec3<double>::fromGeod(const SGGeod& geod)
+{
+  SGVec3<double> cart;
+  SGGeodesy::SGGeodToCart(geod, cart);
+  return cart;
+}
+
+template<>
+inline
+SGVec3<float>
+SGVec3<float>::fromGeod(const SGGeod& geod)
+{
+  SGVec3<double> cart;
+  SGGeodesy::SGGeodToCart(geod, cart);
+  return SGVec3<float>(cart(0), cart(1), cart(2));
+}
+
+template<>
+inline
+SGVec3<double>
+SGVec3<double>::fromGeoc(const SGGeoc& geoc)
+{
+  SGVec3<double> cart;
+  SGGeodesy::SGGeocToCart(geoc, cart);
+  return cart;
+}
+
+template<>
+inline
+SGVec3<float>
+SGVec3<float>::fromGeoc(const SGGeoc& geoc)
+{
+  SGVec3<double> cart;
+  SGGeodesy::SGGeocToCart(geoc, cart);
+  return SGVec3<float>(cart(0), cart(1), cart(2));
+}
+
 /// Unary +, do nothing ...
 template<typename T>
 inline
@@ -173,6 +219,73 @@ SGVec3<T>
 operator*(const SGVec3<T>& v, S s)
 { return SGVec3<T>(s*v(0), s*v(1), s*v(2)); }
 
+/// multiplication as a multiplicator, that is assume that the first vector
+/// represents a 3x3 diagonal matrix with the diagonal elements in the vector.
+/// Then the result is the product of that matrix times the second vector.
+template<typename T>
+inline
+SGVec3<T>
+mult(const SGVec3<T>& v1, const SGVec3<T>& v2)
+{ return SGVec3<T>(v1(0)*v2(0), v1(1)*v2(1), v1(2)*v2(2)); }
+
+/// component wise min
+template<typename T>
+inline
+SGVec3<T>
+min(const SGVec3<T>& v1, const SGVec3<T>& v2)
+{
+  return SGVec3<T>(SGMisc<T>::min(v1(0), v2(0)),
+                   SGMisc<T>::min(v1(1), v2(1)),
+                   SGMisc<T>::min(v1(2), v2(2)));
+}
+template<typename S, typename T>
+inline
+SGVec3<T>
+min(const SGVec3<T>& v, S s)
+{
+  return SGVec3<T>(SGMisc<T>::min(s, v(0)),
+                   SGMisc<T>::min(s, v(1)),
+                   SGMisc<T>::min(s, v(2)));
+}
+template<typename S, typename T>
+inline
+SGVec3<T>
+min(S s, const SGVec3<T>& v)
+{
+  return SGVec3<T>(SGMisc<T>::min(s, v(0)),
+                   SGMisc<T>::min(s, v(1)),
+                   SGMisc<T>::min(s, v(2)));
+}
+
+/// component wise max
+template<typename T>
+inline
+SGVec3<T>
+max(const SGVec3<T>& v1, const SGVec3<T>& v2)
+{
+  return SGVec3<T>(SGMisc<T>::max(v1(0), v2(0)),
+                   SGMisc<T>::max(v1(1), v2(1)),
+                   SGMisc<T>::max(v1(2), v2(2)));
+}
+template<typename S, typename T>
+inline
+SGVec3<T>
+max(const SGVec3<T>& v, S s)
+{
+  return SGVec3<T>(SGMisc<T>::max(s, v(0)),
+                   SGMisc<T>::max(s, v(1)),
+                   SGMisc<T>::max(s, v(2)));
+}
+template<typename S, typename T>
+inline
+SGVec3<T>
+max(S s, const SGVec3<T>& v)
+{
+  return SGVec3<T>(SGMisc<T>::max(s, v(0)),
+                   SGMisc<T>::max(s, v(1)),
+                   SGMisc<T>::max(s, v(2)));
+}
+
 /// Scalar dot product
 template<typename T>
 inline
@@ -202,6 +315,13 @@ T
 norm1(const SGVec3<T>& v)
 { return fabs(v(0)) + fabs(v(1)) + fabs(v(2)); }
 
+/// The inf-norm of the vector
+template<typename T>
+inline
+T
+normI(const SGVec3<T>& v)
+{ return SGMisc<T>::max(fabs(v(0)), fabs(v(1)), fabs(v(2))); }
+
 /// Vector cross product
 template<typename T>
 inline
@@ -213,12 +333,43 @@ cross(const SGVec3<T>& v1, const SGVec3<T>& v2)
                    v1(0)*v2(1) - v1(1)*v2(0));
 }
 
-/// The euclidean norm of the vector, that is what most people call length
+/// return any normalized vector perpendicular to v
+template<typename T>
+inline
+SGVec3<T>
+perpendicular(const SGVec3<T>& v)
+{
+  T absv1 = fabs(v(0));
+  T absv2 = fabs(v(1));
+  T absv3 = fabs(v(2));
+
+  if (absv2 < absv1 && absv3 < absv1) {
+    T quot = v(1)/v(0);
+    return (1/sqrt(1+quot*quot))*SGVec3<T>(quot, -1, 0);
+  } else if (absv3 < absv2) {
+    T quot = v(2)/v(1);
+    return (1/sqrt(1+quot*quot))*SGVec3<T>(0, quot, -1);
+  } else if (SGLimits<T>::min() < absv3) {
+    T quot = v(0)/v(2);
+    return (1/sqrt(1+quot*quot))*SGVec3<T>(-1, 0, quot);
+  } else {
+    // the all zero case ...
+    return SGVec3<T>(0, 0, 0);
+  }
+}
+
+/// Construct a unit vector in the given direction.
+/// or the zero vector if the input vector is zero.
 template<typename T>
 inline
 SGVec3<T>
 normalize(const SGVec3<T>& v)
-{ return (1/norm(v))*v; }
+{
+  T normv = norm(v);
+  if (normv <= SGLimits<T>::min())
+    return SGVec3<T>::zeros();
+  return (1/normv)*v;
+}
 
 /// Return true if exactly the same
 template<typename T>
@@ -234,6 +385,43 @@ bool
 operator!=(const SGVec3<T>& v1, const SGVec3<T>& v2)
 { return ! (v1 == v2); }
 
+/// Return true if smaller, good for putting that into a std::map
+template<typename T>
+inline
+bool
+operator<(const SGVec3<T>& v1, const SGVec3<T>& v2)
+{
+  if (v1(0) < v2(0)) return true;
+  else if (v2(0) < v1(0)) return false;
+  else if (v1(1) < v2(1)) return true;
+  else if (v2(1) < v1(1)) return false;
+  else return (v1(2) < v2(2));
+}
+
+template<typename T>
+inline
+bool
+operator<=(const SGVec3<T>& v1, const SGVec3<T>& v2)
+{
+  if (v1(0) < v2(0)) return true;
+  else if (v2(0) < v1(0)) return false;
+  else if (v1(1) < v2(1)) return true;
+  else if (v2(1) < v1(1)) return false;
+  else return (v1(2) <= v2(2));
+}
+
+template<typename T>
+inline
+bool
+operator>(const SGVec3<T>& v1, const SGVec3<T>& v2)
+{ return operator<(v2, v1); }
+
+template<typename T>
+inline
+bool
+operator>=(const SGVec3<T>& v1, const SGVec3<T>& v2)
+{ return operator<=(v2, v1); }
+
 /// Return true if equal to the relative tolerance tol
 template<typename T>
 inline
@@ -258,6 +446,32 @@ equivalent(const SGVec3<T>& v1, const SGVec3<T>& v2)
   return equivalent(v1, v2, tol, tol);
 }
 
+/// The euclidean distance of the two vectors
+template<typename T>
+inline
+T
+dist(const SGVec3<T>& v1, const SGVec3<T>& v2)
+{ return norm(v1 - v2); }
+
+/// The squared euclidean distance of the two vectors
+template<typename T>
+inline
+T
+distSqr(const SGVec3<T>& v1, const SGVec3<T>& v2)
+{ SGVec3<T> tmp = v1 - v2; return dot(tmp, tmp); }
+
+// calculate the projection of u along the direction of d.
+template<typename T>
+inline
+SGVec3<T>
+projection(const SGVec3<T>& u, const SGVec3<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
@@ -276,10 +490,6 @@ std::basic_ostream<char_type, traits_type>&
 operator<<(std::basic_ostream<char_type, traits_type>& s, const SGVec3<T>& v)
 { return s << "[ " << v(0) << ", " << v(1) << ", " << v(2) << " ]"; }
 
-/// Two classes doing actually the same on different types
-typedef SGVec3<float> SGVec3f;
-typedef SGVec3<double> SGVec3d;
-
 inline
 SGVec3f
 toVec3f(const SGVec3d& v)