virtualx-engine/thirdparty/recastnavigation/Recast/Include/RecastAlloc.h
2017-09-04 21:41:57 +01:00

146 lines
5 KiB
C++

//
// Copyright (c) 2009-2010 Mikko Mononen memon@inside.org
//
// This software is provided 'as-is', without any express or implied
// warranty. In no event will the authors be held liable for any damages
// arising from the use of this software.
// Permission is granted to anyone to use this software for any purpose,
// including commercial applications, and to alter it and redistribute it
// freely, subject to the following restrictions:
// 1. The origin of this software must not be misrepresented; you must not
// claim that you wrote the original software. If you use this software
// in a product, an acknowledgment in the product documentation would be
// appreciated but is not required.
// 2. Altered source versions must be plainly marked as such, and must not be
// misrepresented as being the original software.
// 3. This notice may not be removed or altered from any source distribution.
//
#ifndef RECASTALLOC_H
#define RECASTALLOC_H
#include <stddef.h>
/// Provides hint values to the memory allocator on how long the
/// memory is expected to be used.
enum rcAllocHint
{
RC_ALLOC_PERM, ///< Memory will persist after a function call.
RC_ALLOC_TEMP ///< Memory used temporarily within a function.
};
/// A memory allocation function.
// @param[in] size The size, in bytes of memory, to allocate.
// @param[in] rcAllocHint A hint to the allocator on how long the memory is expected to be in use.
// @return A pointer to the beginning of the allocated memory block, or null if the allocation failed.
/// @see rcAllocSetCustom
typedef void* (rcAllocFunc)(size_t size, rcAllocHint hint);
/// A memory deallocation function.
/// @param[in] ptr A pointer to a memory block previously allocated using #rcAllocFunc.
/// @see rcAllocSetCustom
typedef void (rcFreeFunc)(void* ptr);
/// Sets the base custom allocation functions to be used by Recast.
/// @param[in] allocFunc The memory allocation function to be used by #rcAlloc
/// @param[in] freeFunc The memory de-allocation function to be used by #rcFree
void rcAllocSetCustom(rcAllocFunc *allocFunc, rcFreeFunc *freeFunc);
/// Allocates a memory block.
/// @param[in] size The size, in bytes of memory, to allocate.
/// @param[in] hint A hint to the allocator on how long the memory is expected to be in use.
/// @return A pointer to the beginning of the allocated memory block, or null if the allocation failed.
/// @see rcFree
void* rcAlloc(size_t size, rcAllocHint hint);
/// Deallocates a memory block.
/// @param[in] ptr A pointer to a memory block previously allocated using #rcAlloc.
/// @see rcAlloc
void rcFree(void* ptr);
/// A simple dynamic array of integers.
class rcIntArray
{
int* m_data;
int m_size, m_cap;
void doResize(int n);
// Explicitly disabled copy constructor and copy assignment operator.
rcIntArray(const rcIntArray&);
rcIntArray& operator=(const rcIntArray&);
public:
/// Constructs an instance with an initial array size of zero.
rcIntArray() : m_data(0), m_size(0), m_cap(0) {}
/// Constructs an instance initialized to the specified size.
/// @param[in] n The initial size of the integer array.
rcIntArray(int n) : m_data(0), m_size(0), m_cap(0) { resize(n); }
~rcIntArray() { rcFree(m_data); }
/// Specifies the new size of the integer array.
/// @param[in] n The new size of the integer array.
void resize(int n)
{
if (n > m_cap)
doResize(n);
m_size = n;
}
/// Push the specified integer onto the end of the array and increases the size by one.
/// @param[in] item The new value.
void push(int item) { resize(m_size+1); m_data[m_size-1] = item; }
/// Returns the value at the end of the array and reduces the size by one.
/// @return The value at the end of the array.
int pop()
{
if (m_size > 0)
m_size--;
return m_data[m_size];
}
/// The value at the specified array index.
/// @warning Does not provide overflow protection.
/// @param[in] i The index of the value.
const int& operator[](int i) const { return m_data[i]; }
/// The value at the specified array index.
/// @warning Does not provide overflow protection.
/// @param[in] i The index of the value.
int& operator[](int i) { return m_data[i]; }
/// The current size of the integer array.
int size() const { return m_size; }
};
/// A simple helper class used to delete an array when it goes out of scope.
/// @note This class is rarely if ever used by the end user.
template<class T> class rcScopedDelete
{
T* ptr;
public:
/// Constructs an instance with a null pointer.
inline rcScopedDelete() : ptr(0) {}
/// Constructs an instance with the specified pointer.
/// @param[in] p An pointer to an allocated array.
inline rcScopedDelete(T* p) : ptr(p) {}
inline ~rcScopedDelete() { rcFree(ptr); }
/// The root array pointer.
/// @return The root array pointer.
inline operator T*() { return ptr; }
private:
// Explicitly disabled copy constructor and copy assignment operator.
rcScopedDelete(const rcScopedDelete&);
rcScopedDelete& operator=(const rcScopedDelete&);
};
#endif