summaryrefslogtreecommitdiff
path: root/inc/MeshVS_Buffer.hxx
blob: 531f69f6113ae07bb81dbdf0e9b250793dbad6b7 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
// File:      MeshVS_Buffer.hxx
// Created:   07.03.07 15:53:17
// Author:    msv@EUCLIDEX
// Copyright: Open CASCADE 2007

#ifndef MeshVS_Buffer_HeaderFile
#define MeshVS_Buffer_HeaderFile

#include <Standard.hxx>

/**
 * General purpose buffer that is allocated on the stack with a
 * constant size MeshVS_BufSize, or is allocated dynamically if the requested
 * size exceeds the standard one.
 * It is useful when an allocation of an array of unknown size is needed,
 * and most often the array is small enough to allocate as automatic C array.
 */

//! define the constant to the size of 10 points
#define MeshVS_BufSize 10*3*sizeof(double)

class MeshVS_Buffer 
{
public:
  //! Constructor of the buffer of the requested size
  MeshVS_Buffer (const Standard_Size theSize)
    : myDynData (0)
  {
    if (theSize > MeshVS_BufSize)
      myDynData = Standard::Allocate (theSize);
  }

  //! Destructor
  ~MeshVS_Buffer()
  {
    if (myDynData)
    {
      Standard::Free (myDynData);
      myDynData = 0;
    }
  }

  //! Cast the buffer to the void pointer
  operator void* ()
  {
    return myDynData ? myDynData : (void*) myAutoData;
  }

  //! Interpret the buffer as a reference to double
  operator Standard_Real& ()
  {
    return * (myDynData ? (Standard_Real*) myDynData : (Standard_Real*) myAutoData);
  }

  //! Interpret the buffer as a reference to int
  operator Standard_Integer& ()
  {
    return * (myDynData ? (Standard_Integer*) myDynData : (Standard_Integer*) myAutoData);
  }

private:
  //! Deprecate copy constructor
  MeshVS_Buffer(const MeshVS_Buffer&) {}

  //! Deprecate copy operation
  MeshVS_Buffer& operator=(const MeshVS_Buffer&) {return *this;}

  char  myAutoData[ MeshVS_BufSize ];
  void* myDynData;
};

#endif