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// This code contains NVIDIA Confidential Information and is disclosed to you
// under a form of NVIDIA software license agreement provided separately to you.
//
// Notice
// NVIDIA Corporation and its licensors retain all intellectual property and
// proprietary rights in and to this software and related documentation and
// any modifications thereto. Any use, reproduction, disclosure, or
// distribution of this software and related documentation without an express
// license agreement from NVIDIA Corporation is strictly prohibited.
//
// ALL NVIDIA DESIGN SPECIFICATIONS, CODE ARE PROVIDED "AS IS.". NVIDIA MAKES
// NO WARRANTIES, EXPRESSED, IMPLIED, STATUTORY, OR OTHERWISE WITH RESPECT TO
// THE MATERIALS, AND EXPRESSLY DISCLAIMS ALL IMPLIED WARRANTIES OF NONINFRINGEMENT,
// MERCHANTABILITY, AND FITNESS FOR A PARTICULAR PURPOSE.
//
// Information and code furnished is believed to be accurate and reliable.
// However, NVIDIA Corporation assumes no responsibility for the consequences of use of such
// information or for any infringement of patents or other rights of third parties that may
// result from its use. No license is granted by implication or otherwise under any patent
// or patent rights of NVIDIA Corporation. Details are subject to change without notice.
// This code supersedes and replaces all information previously supplied.
// NVIDIA Corporation products are not authorized for use as critical
// components in life support devices or systems without express written approval of
// NVIDIA Corporation.
//
// Copyright (c) 2008-2017 NVIDIA Corporation. All rights reserved.
// Copyright (c) 2004-2008 AGEIA Technologies, Inc. All rights reserved.
// Copyright (c) 2001-2004 NovodeX AG. All rights reserved.
#include "PxTkRandom.h"
#include "foundation/PxQuat.h"
using namespace physx;
using namespace PxToolkit;
static RandomR250 gRandomR250(0x95d6739b);
PxVec3 BasicRandom::unitRandomPt()
{
PxVec3 v;
do
{
v.x = randomFloat();
v.y = randomFloat();
v.z = randomFloat();
}
while(v.normalize()<1e-6f);
return v;
}
PxQuat BasicRandom::unitRandomQuat()
{
PxQuat v;
do
{
v.x = randomFloat();
v.y = randomFloat();
v.z = randomFloat();
v.w = randomFloat();
}
while(v.normalize()<1e-6f);
return v;
}
void BasicRandom::unitRandomPt(PxVec3& v)
{
v = unitRandomPt();
}
void BasicRandom::unitRandomQuat(PxQuat& v)
{
v = unitRandomQuat();
}
void PxToolkit::SetSeed(PxU32 seed)
{
gRandomR250.setSeed(seed);
}
PxU32 PxToolkit::Rand()
{
return gRandomR250.randI() & TEST_MAX_RAND;
}
RandomR250::RandomR250(PxI32 s)
{
setSeed(s);
}
void RandomR250::setSeed(PxI32 s)
{
BasicRandom lcg(s);
mIndex = 0;
PxI32 j;
for (j = 0; j < 250; j++) // fill r250 buffer with bit values
mBuffer[j] = lcg.randomize();
for (j = 0; j < 250; j++) // set some MSBs to 1
if ( lcg.randomize() > 0x40000000L )
mBuffer[j] |= 0x80000000L;
PxU32 msb = 0x80000000; // turn on diagonal bit
PxU32 mask = 0xffffffff; // turn off the leftmost bits
for (j = 0; j < 32; j++)
{
const PxI32 k = 7 * j + 3; // select a word to operate on
mBuffer[k] &= mask; // turn off bits left of the diagonal
mBuffer[k] |= msb; // turn on the diagonal bit
mask >>= 1;
msb >>= 1;
}
}
PxU32 RandomR250::randI()
{
PxI32 j;
// wrap pointer around
if ( mIndex >= 147 ) j = mIndex - 147;
else j = mIndex + 103;
const PxU32 new_rand = mBuffer[ mIndex ] ^ mBuffer[ j ];
mBuffer[ mIndex ] = new_rand;
// increment pointer for next time
if ( mIndex >= 249 ) mIndex = 0;
else mIndex++;
return new_rand >> 1;
}
PxReal RandomR250::randUnit()
{
PxU32 mask = (1<<23)-1;
return PxF32(randI()&(mask))/PxF32(mask);
}
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