Merge branch 'stableDistPointTriangle' into 'master'

Stable versions of distPointTriangleSquared and distPointTriangle

added stable versions (for degenerate triangles return the distance to the longest edge) for distPointTriangleSquared and distPointTriangle

See merge request !3

ACG/Geometry/Algorithms.cc

@@ -41,7 +41,7 @@
 
 /*===========================================================================*\
  *                                                                           *
- *   $Revision$                                                       *
+ *   $Revision$                                                        *
  *   $Author$                                                      *
  *   $Date$                   *
  *                                                                           *
@@ -313,16 +313,16 @@ distPointLineSquared( const Vec& _p,
   return d1.sqrnorm();
 }    
 
-//-----------------------------------------------------------------------------
-
+  //-----------------------------------------------------------------------------
 
 template <class Vec>
 typename Vec::value_type
 distPointTriangleSquared( const Vec& _p,
-			  const Vec& _v0,
-			  const Vec& _v1,
-			  const Vec& _v2,
-			  Vec& _nearestPoint )
+                          const Vec& _v0,
+                          const Vec& _v1,
+                          const Vec& _v2,
+                          Vec& _nearestPoint,
+                          bool _stable)
 {
   Vec v0v1 = _v1 - _v0;
   Vec v0v2 = _v2 - _v0;
@@ -332,8 +332,23 @@ distPointTriangleSquared( const Vec& _p,
   
   // Check if the triangle is degenerated
   if (d < FLT_MIN && d > -FLT_MIN) {
-    std::cerr << "distPointTriangleSquared: Degenerated triangle !\n";
-    return -1.0;
+    if (_stable) {
+      const double l0 = v0v1.sqrnorm();
+      const double l1 = v0v2.sqrnorm();
+      const double l2 = (_v2 - _v1).sqrnorm();
+      if (l0 > l1 && l0 > l2) {
+        return distPointLineSquared(_p, _v0, _v1, &_nearestPoint);
+      }
+      else if (l1 > l0 && l1 > l2) {
+        return distPointLineSquared(_p, _v0, _v2, &_nearestPoint);
+      }
+      else {
+        return distPointLineSquared(_p, _v1, _v2, &_nearestPoint);
+      }
+    } else {
+      std::cerr << "distPointTriangleSquared: Degenerated triangle !\n";
+      return -1.0;
+    }
   }
   typename Vec::value_type invD = typename Vec::value_type(1.0) / d;
 
@@ -439,10 +454,40 @@ distPointTriangleSquared( const Vec& _p,
   return (_nearestPoint - _p).sqrnorm();
 }
 
+//-----------------------------------------------------------------------------
+
+
+template <class Vec>
+typename Vec::value_type
+distPointTriangleSquared( const Vec& _p,
+                          const Vec& _v0,
+                          const Vec& _v1,
+                          const Vec& _v2,
+                          Vec& _nearestPoint )
+{
+  return distPointTriangleSquared(_p, _v0, _v1, _v2, _nearestPoint, false);
+}
+
 
 //-----------------------------------------------------------------------------
 
 
+template <class Vec>
+typename Vec::value_type
+distPointTriangleSquaredStable( const Vec& _p,
+                                const Vec& _v0,
+                                const Vec& _v1,
+                                const Vec& _v2,
+                                Vec& _nearestPoint )
+{
+  return distPointTriangleSquared(_p, _v0, _v1, _v2, _nearestPoint, true);
+}
+
+
+//-----------------------------------------------------------------------------
+
+
+
 //
 // Modified code of Dave Eberly (www.magic-software.com)
 //

ACG/Geometry/Algorithms.hh

@@ -308,6 +308,25 @@ distPointTriangleSquared( const Vec& _p,
                           const Vec& _v2,
                           Vec& _nearestPoint );
 
+/** \brief squared distance from point _p to triangle (_v0, _v1, _v2)
+*
+*  In the stable version the distance to the longest edge 
+*  is returned if the triangle is degenerate.
+*
+* @param _p   point to test against triangle
+* @param _v0  First point of triangle
+* @param _v1  Second point of triangle
+* @param _v2  Third point of triangle
+* @return     Computed distance
+*/
+template <class Vec>
+typename Vec::value_type
+distPointTriangleSquaredStable( const Vec& _p,
+                                const Vec& _v0,
+                                const Vec& _v1,
+                                const Vec& _v2,
+                                Vec& _nearestPoint );
+
 /// distance from point _p to triangle (_v0, _v1, _v2)
 template <class Vec>
 typename Vec::value_type
@@ -318,6 +337,25 @@ distPointTriangle( const Vec& _p,
                    Vec& _nearestPoint )
 { return sqrt(distPointTriangleSquared(_p, _v0, _v1, _v2, _nearestPoint)); }
 
+/** \brief distance from point _p to triangle (_v0, _v1, _v2)
+*
+*   In the stable version the distance to the longest edge 
+*   is returned if the triangle is degenerate.
+* 
+* @param _v0  First point of triangle
+* @param _v1  Second point of triangle
+* @param _v2  Third point of triangle
+* @return     Computed distance
+ */
+template <class Vec>
+typename Vec::value_type
+distPointTriangleStable( const Vec& _p,
+                         const Vec& _v0,
+                         const Vec& _v1,
+                         const Vec& _v2,
+                         Vec& _nearestPoint )
+{ return sqrt(distPointTriangleSquaredStable(_p, _v0, _v1, _v2, _nearestPoint)); }
+
 /** \brief Checks the distance from a point to a plane
 *
 *
@@ -542,6 +580,9 @@ int isObtuse(const VectorT& _p0,
 
 /** \brief return squared area of triangle (_v0, _v1, _v2)
 *
+* @param _v0  First point of triangle
+* @param _v1  Second point of triangle
+* @param _v2  Third point of triangl
 */
 template <class Vec>
 typename Vec::value_type
@@ -552,6 +593,9 @@ triangleAreaSquared( const Vec& _v0,
 
 /** \brief return area of triangle (_v0, _v1, _v2)
 *
+* @param _v0  First point of triangle
+* @param _v1  Second point of triangle
+* @param _v2  Third point of triangl
 */
 template <class Vec>
 typename Vec::value_type
@@ -565,6 +609,9 @@ triangleArea( const Vec& _v0,
 
 /** \brief return aspect ratio (length/height) of triangle
 *
+* @param _v0  First point of triangle
+* @param _v1  Second point of triangle
+* @param _v2  Third point of triangl
 */
 template <typename Scalar, int N>
 Scalar
@@ -574,6 +621,9 @@ aspectRatio( const VectorT<Scalar, N>& _v0,
 
 /** \brief return roundness of triangle: 1=equilateral, 0=colinear
 *
+* @param _v0  First point of triangle
+* @param _v1  Second point of triangle
+* @param _v2  Third point of triangl
 */
 template <typename Scalar, int N>
 Scalar

OpenFlipper/Documentation/DeveloperHelpSources/changelog.docu

@@ -13,6 +13,7 @@
              - increase max supported face size closes #2522
         - Geometry
              - add fast algorithms for bspline basis function to ACG
+             - Added more stable dist_point triangle Algorithm Version
         - GL
              - implicitly bind vbo on upload()
              - fix shaders for resolving multisampled textures