X-Git-Url: https://git.mxchange.org/?a=blobdiff_plain;f=simgear%2Fmath%2FSGPlane.hxx;h=971e72c8e0e70eef11cba60d708903bd167bcd36;hb=914d3e6a2b323cf9f186cbef2aef7865ea07b309;hp=e7755e0efc983052015171ea606fd414829f8238;hpb=de020ee69524393daf11200aa0a46bfd5aa2409a;p=simgear.git

diff --git a/simgear/math/SGPlane.hxx b/simgear/math/SGPlane.hxx
index e7755e0e..971e72c8 100644
--- a/simgear/math/SGPlane.hxx
+++ b/simgear/math/SGPlane.hxx
@@ -23,14 +23,25 @@ class SGPlane {
 public:
   SGPlane()
   { }
-  SGPlane(const SGVec3<T>& normal, T dist) :
+  SGPlane(const SGVec3<T>& normal, const T& dist) :
     _normal(normal), _dist(dist)
   { }
+  SGPlane(const SGVec3<T>& normal, const SGVec3<T>& point) :
+    _normal(normal), _dist(-dot(normal, point))
+  { }
   SGPlane(const SGVec3<T> vertices[3]) :
     _normal(normalize(cross(vertices[1] - vertices[0],
                             vertices[2] - vertices[0]))),
     _dist(-dot(_normal, vertices[0]))
   { }
+  SGPlane(const SGVec3<T>& v0, const SGVec3<T>& v1, const SGVec3<T>& v2) :
+    _normal(normalize(cross(v1 - v0, v2 - v0))),
+    _dist(-dot(_normal, v0))
+  { }
+  template<typename S>
+  explicit SGPlane(const SGPlane<S>& plane) :
+    _normal(plane.getNormal()), _dist(plane.getDist())
+  { }
 
   void setNormal(const SGVec3<T>& normal)
   { _normal = normal; }
@@ -42,6 +53,10 @@ public:
   const T& getDist() const
   { return _dist; }
 
+  /// Return a point on the plane 
+  SGVec3<T> getPointOnPlane() const
+  { return -_dist*_normal; }
+
   /// That is the distance where we measure positive in direction of the normal
   T getPositiveDist() const
   { return -_dist; }