- added the set_error_tolerance_factor function to ModBaseT and implemented it in inherited classes as necessary

- added the set_error_tolerance_factor function to BaseDecimaterT, which calls set_error_tolerance_factor for all loaded Mods
- implemented a decimate_constraints_only function for the McDecimater (and adjusted the MixedDecimater accordingly)
- implemented stop criterions for the McDecimater
- added some OpenMP loops for the sample generation to the McDecimater

git-svn-id: http://www.openmesh.org/svnrepo/OpenMesh/trunk@685 fdac6126-5c0c-442c-9429-916003d36597

src/OpenMesh/Tools/Decimater/ModNormalDeviationT.hh

@@ -87,7 +87,7 @@ template <class MeshT>
 class ModNormalDeviationT : public ModBaseT< MeshT >
 {
 public:
-   
+
   DECIMATING_MODULE( ModNormalDeviationT, MeshT, NormalDeviation );
 
   typedef typename Mesh::Scalar                     Scalar;
@@ -191,6 +191,18 @@ public:
     return (max_angle < 0.5 * normal_deviation_ ? max_angle : float( Base::ILLEGAL_COLLAPSE ));
   }
 
+  /// set the percentage of normal deviation
+  void set_error_tolerance_factor(double _factor) {
+    if (_factor >= 0.0 && _factor <= 1.0) {
+      // the smaller the factor, the smaller normal_deviation_ gets
+      // thus creating a stricter constraint
+      // division by error_tolerance_factor_ is for normalization
+      Scalar normal_deviation = (normal_deviation_ * 180.0/M_PI) * _factor / this->error_tolerance_factor_;
+      set_normal_deviation(normal_deviation);
+      this->error_tolerance_factor_ = _factor;
+    }
+  }
+
 
   void  postprocess_collapse(const CollapseInfo& _ci) {
     // account for changed normals