X-Git-Url: https://git.mxchange.org/?a=blobdiff_plain;f=simgear%2Fmath%2FSGTriangle.hxx;h=af6f32f14b8404145465e5bc58e53a34f8aac333;hb=578af00b0d48100c540154f54293a1b77a0655fe;hp=2cba610a582648903fbd0142892af02df85c5f78;hpb=4a4e8c87b8f5b224350d9407d529f8cfe8e68553;p=simgear.git

diff --git a/simgear/math/SGTriangle.hxx b/simgear/math/SGTriangle.hxx
index 2cba610a..af6f32f1 100644
--- a/simgear/math/SGTriangle.hxx
+++ b/simgear/math/SGTriangle.hxx
@@ -42,13 +42,7 @@ public:
   }
 
   SGVec3<T> getCenter() const
-  {
-    SGBox<T> box;
-    box.expandBy(_v0);
-    box.expandBy(_v0 + _d[0]);
-    box.expandBy(_v0 + _d[1]);
-    return box.getCenter();
-  }
+  { return _v0 + T(1)/T(3)*(_d[0] + _d[1]); }
 
   // note that the index is unchecked
   SGVec3<T> getVertex(unsigned i) const
@@ -77,6 +71,16 @@ public:
     _d[0] = _d[1];
     _d[1] = tmp;
   }
+
+  SGTriangle<T> transform(const SGMatrix<T>& matrix) const
+  {
+    SGTriangle<T> triangle;
+    triangle._v0 = matrix.xformPt(_v0);
+    triangle._d[0] = matrix.xformVec(_d[0]);
+    triangle._d[1] = matrix.xformVec(_d[1]);
+    return triangle;
+  }
+
 private:
   /// Store one vertex directly, _d is the offset of the other two
   /// vertices wrt the base vertex