Box2D  2.3.0
A 2D Physics Engine for Games
b2GrowableStack.h
1 /*
2 * Copyright (c) 2010 Erin Catto http://www.box2d.org
3 *
4 * This software is provided 'as-is', without any express or implied
5 * warranty. In no event will the authors be held liable for any damages
6 * arising from the use of this software.
7 * Permission is granted to anyone to use this software for any purpose,
8 * including commercial applications, and to alter it and redistribute it
9 * freely, subject to the following restrictions:
10 * 1. The origin of this software must not be misrepresented; you must not
11 * claim that you wrote the original software. If you use this software
12 * in a product, an acknowledgment in the product documentation would be
13 * appreciated but is not required.
14 * 2. Altered source versions must be plainly marked as such, and must not be
15 * misrepresented as being the original software.
16 * 3. This notice may not be removed or altered from any source distribution.
17 */
18 
19 #ifndef B2_GROWABLE_STACK_H
20 #define B2_GROWABLE_STACK_H
22 #include <memory.h>
23 
27 template <typename T, int32 N>
29 {
30 public:
32  {
33  m_stack = m_array;
34  m_count = 0;
35  m_capacity = N;
36  }
37 
39  {
40  if (m_stack != m_array)
41  {
42  b2Free(m_stack);
43  m_stack = NULL;
44  }
45  }
46 
47  void Push(const T& element)
48  {
49  if (m_count == m_capacity)
50  {
51  T* old = m_stack;
52  m_capacity *= 2;
53  m_stack = (T*)b2Alloc(m_capacity * sizeof(T));
54  memcpy(m_stack, old, m_count * sizeof(T));
55  if (old != m_array)
56  {
57  b2Free(old);
58  }
59  }
60 
61  m_stack[m_count] = element;
62  ++m_count;
63  }
64 
65  T Pop()
66  {
67  b2Assert(m_count > 0);
68  --m_count;
69  return m_stack[m_count];
70  }
71 
72  int32 GetCount()
73  {
74  return m_count;
75  }
76 
77 private:
78  T* m_stack;
79  T m_array[N];
80  int32 m_count;
81  int32 m_capacity;
82 };
83 
84 
85 #endif