119 lines
2.8 KiB
C++
119 lines
2.8 KiB
C++
/*
|
|
Copyright (c) 2003-2006 Gino van den Bergen / Erwin Coumans https://bulletphysics.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.
|
|
*/
|
|
|
|
/*
|
|
StackAlloc extracted from GJK-EPA collision solver by Nathanael Presson
|
|
Nov.2006
|
|
*/
|
|
|
|
#ifndef BT_STACK_ALLOC
|
|
#define BT_STACK_ALLOC
|
|
|
|
#include "btScalar.h" //for btAssert
|
|
#include "btAlignedAllocator.h"
|
|
|
|
///The btBlock class is an internal structure for the btStackAlloc memory allocator.
|
|
struct btBlock
|
|
{
|
|
btBlock* previous;
|
|
unsigned char* address;
|
|
};
|
|
|
|
///The StackAlloc class provides some fast stack-based memory allocator (LIFO last-in first-out)
|
|
class btStackAlloc
|
|
{
|
|
public:
|
|
btStackAlloc(unsigned int size)
|
|
{
|
|
ctor();
|
|
create(size);
|
|
}
|
|
~btStackAlloc() { destroy(); }
|
|
|
|
inline void create(unsigned int size)
|
|
{
|
|
destroy();
|
|
data = (unsigned char*)btAlignedAlloc(size, 16);
|
|
totalsize = size;
|
|
}
|
|
inline void destroy()
|
|
{
|
|
btAssert(usedsize == 0);
|
|
//Raise(L"StackAlloc is still in use");
|
|
|
|
if (usedsize == 0)
|
|
{
|
|
if (!ischild && data)
|
|
btAlignedFree(data);
|
|
|
|
data = 0;
|
|
usedsize = 0;
|
|
}
|
|
}
|
|
|
|
int getAvailableMemory() const
|
|
{
|
|
return static_cast<int>(totalsize - usedsize);
|
|
}
|
|
|
|
unsigned char* allocate(unsigned int size)
|
|
{
|
|
const unsigned int nus(usedsize + size);
|
|
if (nus < totalsize)
|
|
{
|
|
usedsize = nus;
|
|
return (data + (usedsize - size));
|
|
}
|
|
btAssert(0);
|
|
//&& (L"Not enough memory"));
|
|
|
|
return (0);
|
|
}
|
|
SIMD_FORCE_INLINE btBlock* beginBlock()
|
|
{
|
|
btBlock* pb = (btBlock*)allocate(sizeof(btBlock));
|
|
pb->previous = current;
|
|
pb->address = data + usedsize;
|
|
current = pb;
|
|
return (pb);
|
|
}
|
|
SIMD_FORCE_INLINE void endBlock(btBlock* block)
|
|
{
|
|
btAssert(block == current);
|
|
//Raise(L"Unmatched blocks");
|
|
if (block == current)
|
|
{
|
|
current = block->previous;
|
|
usedsize = (unsigned int)((block->address - data) - sizeof(btBlock));
|
|
}
|
|
}
|
|
|
|
private:
|
|
void ctor()
|
|
{
|
|
data = 0;
|
|
totalsize = 0;
|
|
usedsize = 0;
|
|
current = 0;
|
|
ischild = false;
|
|
}
|
|
unsigned char* data;
|
|
unsigned int totalsize;
|
|
unsigned int usedsize;
|
|
btBlock* current;
|
|
bool ischild;
|
|
};
|
|
|
|
#endif //BT_STACK_ALLOC
|