vtkSOADataArrayTemplate.h

/*=========================================================================

  Program:   Visualization Toolkit
  Module:    vtkSOADataArrayTemplate.h

  Copyright (c) Ken Martin, Will Schroeder, Bill Lorensen
  All rights reserved.
  See Copyright.txt or http://www.kitware.com/Copyright.htm for details.

     This software is distributed WITHOUT ANY WARRANTY; without even
     the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
     PURPOSE.  See the above copyright notice for more information.

=========================================================================*/
/**
 * @class   vtkSOADataArrayTemplate
 * @brief   Struct-Of-Arrays implementation of
 * vtkGenericDataArray.
 *
 *
 * vtkSOADataArrayTemplate is the counterpart of vtkAOSDataArrayTemplate. Each
 * component is stored in a separate array.
 *
 * @sa
 * vtkGenericDataArray vtkAOSDataArrayTemplate
*/

#ifndef vtkSOADataArrayTemplate_h
#define vtkSOADataArrayTemplate_h

#include "vtkCommonCoreModule.h" // For export macro
#include "vtkGenericDataArray.h"
#include "vtkBuffer.h"

// The export macro below makes no sense, but is necessary for older compilers
// when we export instantiations of this class from vtkCommonCore.
template <class ValueTypeT>
class VTKCOMMONCORE_EXPORT vtkSOADataArrayTemplate :
    public vtkGenericDataArray<vtkSOADataArrayTemplate<ValueTypeT>, ValueTypeT>
{
  typedef vtkGenericDataArray<vtkSOADataArrayTemplate<ValueTypeT>, ValueTypeT>
          GenericDataArrayType;
public:
  typedef vtkSOADataArrayTemplate<ValueTypeT> SelfType;
  vtkTemplateTypeMacro(SelfType, GenericDataArrayType)
  typedef typename Superclass::ValueType ValueType;

  enum DeleteMethod
  {
    VTK_DATA_ARRAY_FREE=vtkAbstractArray::VTK_DATA_ARRAY_FREE,
    VTK_DATA_ARRAY_DELETE=vtkAbstractArray::VTK_DATA_ARRAY_DELETE,
    VTK_DATA_ARRAY_ALIGNED_FREE=vtkAbstractArray::VTK_DATA_ARRAY_ALIGNED_FREE
  };

  static vtkSOADataArrayTemplate* New();

  //@{
  /**
   * Get the value at @a valueIdx. @a valueIdx assumes AOS ordering.
   */
  inline ValueType GetValue(vtkIdType valueIdx) const
  {
    vtkIdType tupleIdx;
    int comp;
    this->GetTupleIndexFromValueIndex(valueIdx, tupleIdx, comp);
    return this->GetTypedComponent(tupleIdx, comp);
  }
  //@}

  //@{
  /**
   * Set the value at @a valueIdx to @a value. @a valueIdx assumes AOS ordering.
   */
  inline void SetValue(vtkIdType valueIdx, ValueType value)
  {
    vtkIdType tupleIdx;
    int comp;
    this->GetTupleIndexFromValueIndex(valueIdx, tupleIdx, comp);
    this->SetTypedComponent(tupleIdx, comp, value);
  }
  //@}

  /**
   * Copy the tuple at @a tupleIdx into @a tuple.
   */
  inline void GetTypedTuple(vtkIdType tupleIdx, ValueType* tuple) const
  {
    for (size_t cc=0; cc < this->Data.size(); cc++)
    {
      tuple[cc] = this->Data[cc]->GetBuffer()[tupleIdx];
    }
  }

  /**
   * Set this array's tuple at @a tupleIdx to the values in @a tuple.
   */
  inline void SetTypedTuple(vtkIdType tupleIdx, const ValueType* tuple)
  {
    for (size_t cc=0; cc < this->Data.size(); ++cc)
    {
      this->Data[cc]->GetBuffer()[tupleIdx] = tuple[cc];
    }
  }

  /**
   * Get component @a comp of the tuple at @a tupleIdx.
   */
  inline ValueType GetTypedComponent(vtkIdType tupleIdx, int comp) const
  {
    return this->Data[comp]->GetBuffer()[tupleIdx];
  }

  /**
   * Set component @a comp of the tuple at @a tupleIdx to @a value.
   */
  inline void SetTypedComponent(vtkIdType tupleIdx, int comp, ValueType value)
  {
    this->Data[comp]->GetBuffer()[tupleIdx] = value;
  }

  /**
   * Set component @a comp of all tuples to @a value.
   */
  void FillTypedComponent(int compIdx, ValueType value) VTK_OVERRIDE;

  /**
   * Use this API to pass externally allocated memory to this instance. Since
   * vtkSOADataArrayTemplate uses separate contiguous regions for each
   * component, use this API to add arrays for each of the component.
   * \c save: When set to true, vtkSOADataArrayTemplate will not release or
   * realloc the memory even when the AllocatorType is set to RESIZABLE. If
   * needed it will simply allow new memory buffers and "forget" the supplied
   * pointers. When save is set to false, this will be the \c deleteMethod
   * specified to release the array.
   * If updateMaxId is true, the array's MaxId will be updated, and assumes
   * that size is the number of tuples in the array.
   * \c size is specified in number of elements of ScalarType.
   */
  void SetArray(int comp, ValueType* array, vtkIdType size,
                bool updateMaxId = false, bool save=false,
                int deleteMethod=VTK_DATA_ARRAY_FREE);

  /**
   * Return a pointer to a contiguous block of memory containing all values for
   * a particular components (ie. a single array of the struct-of-arrays).
   */
  ValueType* GetComponentArrayPointer(int comp);

  /**
   * Use of this method is discouraged, it creates a deep copy of the data into
   * a contiguous AoS-ordered buffer and prints a warning.
   */
  void *GetVoidPointer(vtkIdType valueIdx) VTK_OVERRIDE;

  /**
   * Export a copy of the data in AoS ordering to the preallocated memory
   * buffer.
   */
  void ExportToVoidPointer(void *ptr) VTK_OVERRIDE;

  //@{
  /**
   * Perform a fast, safe cast from a vtkAbstractArray to a vtkDataArray.
   * This method checks if source->GetArrayType() returns DataArray
   * or a more derived type, and performs a static_cast to return
   * source as a vtkDataArray pointer. Otherwise, NULL is returned.
   */
  static vtkSOADataArrayTemplate<ValueType>*
  FastDownCast(vtkAbstractArray *source)
  {
    if (source)
    {
      switch (source->GetArrayType())
      {
        case vtkAbstractArray::SoADataArrayTemplate:
          if (vtkDataTypesCompare(source->GetDataType(),
                                  vtkTypeTraits<ValueType>::VTK_TYPE_ID))
          {
            return static_cast<vtkSOADataArrayTemplate<ValueType>*>(source);
          }
          break;
      }
    }
    return NULL;
  }
  //@}

  int GetArrayType() VTK_OVERRIDE { return vtkAbstractArray::SoADataArrayTemplate; }
  VTK_NEWINSTANCE vtkArrayIterator *NewIterator() VTK_OVERRIDE;
  void SetNumberOfComponents(int numComps) VTK_OVERRIDE;
  void ShallowCopy(vtkDataArray *other) VTK_OVERRIDE;

  // Reimplemented for efficiency:
  void InsertTuples(vtkIdType dstStart, vtkIdType n, vtkIdType srcStart,
                    vtkAbstractArray* source) VTK_OVERRIDE;
  // MSVC doesn't like 'using' here (error C2487). Just forward instead:
  // using Superclass::InsertTuples;
  void InsertTuples(vtkIdList *dstIds, vtkIdList *srcIds,
                    vtkAbstractArray *source) VTK_OVERRIDE
  { this->Superclass::InsertTuples(dstIds, srcIds, source); }

protected:
  vtkSOADataArrayTemplate();
  ~vtkSOADataArrayTemplate() VTK_OVERRIDE;

  /**
   * Allocate space for numTuples. Old data is not preserved. If numTuples == 0,
   * all data is freed.
   */
  bool AllocateTuples(vtkIdType numTuples);

  /**
   * Allocate space for numTuples. Old data is preserved. If numTuples == 0,
   * all data is freed.
   */
  bool ReallocateTuples(vtkIdType numTuples);

  std::vector<vtkBuffer<ValueType>*> Data;
  vtkBuffer<ValueType> *AoSCopy;

  double NumberOfComponentsReciprocal;

private:
  vtkSOADataArrayTemplate(const vtkSOADataArrayTemplate&) VTK_DELETE_FUNCTION;
  void operator=(const vtkSOADataArrayTemplate&) VTK_DELETE_FUNCTION;

  inline void GetTupleIndexFromValueIndex(vtkIdType valueIdx,
                                          vtkIdType& tupleIdx, int& comp) const
  {
    tupleIdx = static_cast<vtkIdType>(valueIdx *
                                      this->NumberOfComponentsReciprocal);
    comp = valueIdx - (tupleIdx * this->NumberOfComponents);
  }

  friend class vtkGenericDataArray<vtkSOADataArrayTemplate<ValueTypeT>,
                                   ValueTypeT>;
};

// Declare vtkArrayDownCast implementations for SoA containers:
vtkArrayDownCast_TemplateFastCastMacro(vtkSOADataArrayTemplate)

#endif // header guard

// This portion must be OUTSIDE the include blockers. This is used to tell
// libraries other than vtkCommonCore that instantiations of
// vtkSOADataArrayTemplate can be found externally. This prevents each library
// from instantiating these on their own.
#ifdef VTK_SOA_DATA_ARRAY_TEMPLATE_INSTANTIATING
#define VTK_SOA_DATA_ARRAY_TEMPLATE_INSTANTIATE(T) \
  template class VTKCOMMONCORE_EXPORT vtkSOADataArrayTemplate< T >
#elif defined(VTK_USE_EXTERN_TEMPLATE)
#ifndef VTK_SOA_DATA_ARRAY_TEMPLATE_EXTERN
#define VTK_SOA_DATA_ARRAY_TEMPLATE_EXTERN
#ifdef _MSC_VER
#pragma warning (push)
// The following is needed when the vtkSOADataArrayTemplate is declared
// dllexport and is used from another class in vtkCommonCore
#pragma warning (disable: 4910) // extern and dllexport incompatible
#endif
vtkExternTemplateMacro(
  extern template class VTKCOMMONCORE_EXPORT vtkSOADataArrayTemplate)
#ifdef _MSC_VER
#pragma warning (pop)
#endif
#endif // VTK_SOA_DATA_ARRAY_TEMPLATE_EXTERN

// The following clause is only for MSVC 2008 and 2010
#elif defined(_MSC_VER) && !defined(VTK_BUILD_SHARED_LIBS)
#pragma warning (push)

// C4091: 'extern ' : ignored on left of 'int' when no variable is declared
#pragma warning (disable: 4091)

// Compiler-specific extension warning.
#pragma warning (disable: 4231)

// We need to disable warning 4910 and do an extern dllexport
// anyway.  When deriving new arrays from an
// instantiation of this template the compiler does an explicit
// instantiation of the base class.  From outside the vtkCommon
// library we block this using an extern dllimport instantiation.
// For classes inside vtkCommon we should be able to just do an
// extern instantiation, but VS 2008 complains about missing
// definitions.  We cannot do an extern dllimport inside vtkCommon
// since the symbols are local to the dll.  An extern dllexport
// seems to be the only way to convince VS 2008 to do the right
// thing, so we just disable the warning.
#pragma warning (disable: 4910) // extern and dllexport incompatible

// Use an "extern explicit instantiation" to give the class a DLL
// interface.  This is a compiler-specific extension.
vtkInstantiateTemplateMacro(
  extern template class VTKCOMMONCORE_EXPORT vtkSOADataArrayTemplate)

#pragma warning (pop)

#endif

// VTK-HeaderTest-Exclude: vtkSOADataArrayTemplate.h