correction genericInterpolateImageFunction

Code/Common/otbGenericInterpolateImageFunction.h

@@ -98,17 +98,20 @@ public itk::InterpolateImageFunction<TInputImage,TCoordRep>
     } 
     
     /** Delete tables.*/
-    void ResetOffsetTable();
+    void ResetOffsetTable() const;
     /** Initialize used tables*/ 
-    void InitializeTables();    
+    void InitializeTables() const;    
     /** Fill the weight offset table*/
-    void FillWeightOffsetTable();
+    void FillWeightOffsetTable() const;
 
     protected:
     GenericInterpolateImageFunction();
     ~GenericInterpolateImageFunction();
     void PrintSelf(std::ostream& os, itk::Indent indent) const;
- 
+
+    /** Call the superclass implementation and set the TablesHaveBeenGenerated
+     * flag to false */
+    virtual void Modified(void);
 
     private:
     GenericInterpolateImageFunction(const Self&); //purposely not implemented
@@ -118,17 +121,23 @@ public itk::InterpolateImageFunction<TInputImage,TCoordRep>
     // Constant to store twice the radius
     unsigned int m_WindowSize;
 
-     /** The offset array, used to keep a list of relevant
-     * offsets in the neihborhoodIterator */
-    unsigned int *m_OffsetTable;
     /** Used function */
     FunctionType m_Function;
-    /** Size of the offset table */
-    unsigned int m_OffsetTableSize;
     /** Store the image dimension.*/
     unsigned int m_ImageDimension;  
+
+    /** These members are declared mutable so that they can be 
+	regenerated seamlessly inside the EvaluateAtContinuousIndex method if
+	they need to */
+    /** Size of the offset table */
+    mutable unsigned int m_OffsetTableSize;
+    /** The offset array, used to keep a list of relevant
+     * offsets in the neihborhoodIterator */
+    mutable unsigned int *m_OffsetTable;
     /** Index into the weights array for each offset */
-    unsigned int **m_WeightOffsetTable;
+    mutable unsigned int **m_WeightOffsetTable;
+    /** True if internal statistics have been generated */
+    mutable bool m_TablesHaveBeenGenerated;
   };
 
 } // end namespace itk

Code/Common/otbGenericInterpolateImageFunction.txx

@@ -28,6 +28,9 @@ GenericInterpolateImageFunction<TInputImage, TFunction, TBoundaryCondition, TCoo
 {
   //m_Radius = 1;
   m_WindowSize = 1;
+  m_OffsetTable = NULL;
+  m_WeightOffsetTable = NULL;
+  m_TablesHaveBeenGenerated=false;
 }
 
 /** Destructor */
@@ -42,17 +45,25 @@ GenericInterpolateImageFunction<TInputImage, TFunction,TBoundaryCondition, TCoor
 template<class TInputImage, class TFunction, class TBoundaryCondition, class TCoordRep>
 void
 GenericInterpolateImageFunction<TInputImage, TFunction, TBoundaryCondition, TCoordRep>
-::ResetOffsetTable()
+::ResetOffsetTable() const 
 {
   // Clear the offset table
-  delete [] m_OffsetTable;
+  if(m_OffsetTable!=NULL)
+    {
+      delete [] m_OffsetTable;
+      m_OffsetTable=NULL;
+    }
 
-  // Clear the weights tables
-  for(unsigned int i=0; i < m_OffsetTableSize; i++)
+  // Clear the weights tales
+  if(m_WeightOffsetTable!=NULL)
     {
-    delete [] m_WeightOffsetTable[i];
+      for(unsigned int i=0; i < m_OffsetTableSize; i++)
+	{
+	  delete [] m_WeightOffsetTable[i];
+	}
+      delete[] m_WeightOffsetTable;
+      m_WeightOffsetTable = NULL;
     }
-  delete[] m_WeightOffsetTable;
 }
 
 
@@ -78,20 +89,24 @@ GenericInterpolateImageFunction<TInputImage, TFunction, TBoundaryCondition, TCoo
   //m_Radius = rad;
   this->GetFunction().SetRadius(rad);
   m_WindowSize = rad << 1;
-  // Delete existing tables
-  this->ResetOffsetTable();
-  // Tables initialization
-  this->InitializeTables();
-  // fill the weigth table
-  this->FillWeightOffsetTable();
   this->Modified();
 }
 
+template<class TInputImage, class TFunction, class TBoundaryCondition, class TCoordRep>
+void
+GenericInterpolateImageFunction<TInputImage, TFunction, TBoundaryCondition, TCoordRep>
+::Modified()
+{
+  Superclass::Modified();
+  m_TablesHaveBeenGenerated=false;
+  
+}
+
 /** Initialize used tables*/ 
 template<class TInputImage, class TFunction, class TBoundaryCondition, class TCoordRep>
 void
 GenericInterpolateImageFunction<TInputImage, TFunction, TBoundaryCondition, TCoordRep>
-::InitializeTables()
+::InitializeTables() const
 {
   // Compute the offset table size
   m_OffsetTableSize = 1;
@@ -115,7 +130,7 @@ GenericInterpolateImageFunction<TInputImage, TFunction, TBoundaryCondition, TCoo
 template<class TInputImage, class TFunction, class TBoundaryCondition, class TCoordRep>
 void
 GenericInterpolateImageFunction<TInputImage, TFunction, TBoundaryCondition, TCoordRep>
-::FillWeightOffsetTable()
+::FillWeightOffsetTable() const
 {
   // Initialize the neighborhood
   SizeType radius;
@@ -171,6 +186,17 @@ typename GenericInterpolateImageFunction<TInputImage, TFunction, TBoundaryCondit
 GenericInterpolateImageFunction<TInputImage, TFunction, TBoundaryCondition, TCoordRep>
 ::EvaluateAtContinuousIndex(const ContinuousIndexType& index) const
 {
+  if(!m_TablesHaveBeenGenerated)   
+    {
+      // Delete existing tables
+      this->ResetOffsetTable();
+      // Tables initialization
+      this->InitializeTables();
+      // fill the weigth table
+      this->FillWeightOffsetTable();
+      m_TablesHaveBeenGenerated=true;
+    }
+
   unsigned int dim;
   IndexType baseIndex;
   double distance[ImageDimension];