This file is indexed.

/usr/include/bullet/LinearMath/btScalar.h is in libbullet-dev 2.83.6+dfsg-3.

This file is owned by root:root, with mode 0o644.

The actual contents of the file can be viewed below.

  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
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
/*
Copyright (c) 2003-2009 Erwin Coumans  http://bullet.googlecode.com

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 BT_SCALAR_H
#define BT_SCALAR_H

#ifdef BT_MANAGED_CODE
//Aligned data types not supported in managed code
#pragma unmanaged
#endif


#include <math.h>
#include <stdlib.h>//size_t for MSVC 6.0
#include <float.h>

/* SVN $Revision$ on $Date$ from http://bullet.googlecode.com*/
#define BT_BULLET_VERSION 284

inline int	btGetVersion()
{
	return BT_BULLET_VERSION;
}

#if defined(DEBUG) || defined (_DEBUG)
#define BT_DEBUG
#endif


#ifdef _WIN32

		#if defined(__MINGW32__) || defined(__CYGWIN__) || (defined (_MSC_VER) && _MSC_VER < 1300)

			#define SIMD_FORCE_INLINE inline
			#define ATTRIBUTE_ALIGNED16(a) a
			#define ATTRIBUTE_ALIGNED64(a) a
			#define ATTRIBUTE_ALIGNED128(a) a
		#elif (_M_ARM)
			#define SIMD_FORCE_INLINE __forceinline
			#define ATTRIBUTE_ALIGNED16(a) __declspec() a
			#define ATTRIBUTE_ALIGNED64(a) __declspec() a
			#define ATTRIBUTE_ALIGNED128(a) __declspec () a
		#else
			//#define BT_HAS_ALIGNED_ALLOCATOR
			#pragma warning(disable : 4324) // disable padding warning
//			#pragma warning(disable:4530) // Disable the exception disable but used in MSCV Stl warning.
//			#pragma warning(disable:4996) //Turn off warnings about deprecated C routines
//			#pragma warning(disable:4786) // Disable the "debug name too long" warning

			#define SIMD_FORCE_INLINE __forceinline
			#define ATTRIBUTE_ALIGNED16(a) __declspec(align(16)) a
			#define ATTRIBUTE_ALIGNED64(a) __declspec(align(64)) a
			#define ATTRIBUTE_ALIGNED128(a) __declspec (align(128)) a
		#ifdef _XBOX
			#define BT_USE_VMX128

			#include <ppcintrinsics.h>
 			#define BT_HAVE_NATIVE_FSEL
 			#define btFsel(a,b,c) __fsel((a),(b),(c))
		#else

#if defined (_M_ARM)
            //Do not turn SSE on for ARM (may want to turn on BT_USE_NEON however)
#elif (defined (_WIN32) && (_MSC_VER) && _MSC_VER >= 1400) && (!defined (BT_USE_DOUBLE_PRECISION))
			#if _MSC_VER>1400
				#define BT_USE_SIMD_VECTOR3
			#endif

			#define BT_USE_SSE
			#ifdef BT_USE_SSE

#if (_MSC_FULL_VER >= 170050727)//Visual Studio 2012 can compile SSE4/FMA3 (but SSE4/FMA3 is not enabled by default)
			#define BT_ALLOW_SSE4
#endif //(_MSC_FULL_VER >= 160040219)

			//BT_USE_SSE_IN_API is disabled under Windows by default, because 
			//it makes it harder to integrate Bullet into your application under Windows 
			//(structured embedding Bullet structs/classes need to be 16-byte aligned)
			//with relatively little performance gain
			//If you are not embedded Bullet data in your classes, or make sure that you align those classes on 16-byte boundaries
			//you can manually enable this line or set it in the build system for a bit of performance gain (a few percent, dependent on usage)
			//#define BT_USE_SSE_IN_API
			#endif //BT_USE_SSE
			#include <emmintrin.h>
#endif

		#endif//_XBOX

		#endif //__MINGW32__

#ifdef BT_DEBUG
	#ifdef _MSC_VER
		#include <stdio.h>
		#define btAssert(x) { if(!(x)){printf("Assert "__FILE__ ":%u ("#x")\n", __LINE__);__debugbreak();	}}
	#else//_MSC_VER
		#include <assert.h>
		#define btAssert assert
	#endif//_MSC_VER
#else
		#define btAssert(x)
#endif
		//btFullAssert is optional, slows down a lot
		#define btFullAssert(x)

		#define btLikely(_c)  _c
		#define btUnlikely(_c) _c

#else
	
#if defined	(__CELLOS_LV2__)
		#define SIMD_FORCE_INLINE inline __attribute__((always_inline))
		#define ATTRIBUTE_ALIGNED16(a) a __attribute__ ((aligned (16)))
		#define ATTRIBUTE_ALIGNED64(a) a __attribute__ ((aligned (64)))
		#define ATTRIBUTE_ALIGNED128(a) a __attribute__ ((aligned (128)))
		#ifndef assert
		#include <assert.h>
		#endif
#ifdef BT_DEBUG
#ifdef __SPU__
#include <spu_printf.h>
#define printf spu_printf
	#define btAssert(x) {if(!(x)){printf("Assert "__FILE__ ":%u ("#x")\n", __LINE__);spu_hcmpeq(0,0);}}
#else
	#define btAssert assert
#endif
	
#else
		#define btAssert(x)
#endif
		//btFullAssert is optional, slows down a lot
		#define btFullAssert(x)

		#define btLikely(_c)  _c
		#define btUnlikely(_c) _c

#else

#ifdef USE_LIBSPE2

		#define SIMD_FORCE_INLINE __inline
		#define ATTRIBUTE_ALIGNED16(a) a __attribute__ ((aligned (16)))
		#define ATTRIBUTE_ALIGNED64(a) a __attribute__ ((aligned (64)))
		#define ATTRIBUTE_ALIGNED128(a) a __attribute__ ((aligned (128)))
		#ifndef assert
		#include <assert.h>
		#endif
#ifdef BT_DEBUG
		#define btAssert assert
#else
		#define btAssert(x)
#endif
		//btFullAssert is optional, slows down a lot
		#define btFullAssert(x)


		#define btLikely(_c)   __builtin_expect((_c), 1)
		#define btUnlikely(_c) __builtin_expect((_c), 0)
		

#else
	//non-windows systems

#if (defined (__APPLE__) && (!defined (BT_USE_DOUBLE_PRECISION)))
    #if defined (__i386__) || defined (__x86_64__)
		#define BT_USE_SIMD_VECTOR3
		#define BT_USE_SSE
		//BT_USE_SSE_IN_API is enabled on Mac OSX by default, because memory is automatically aligned on 16-byte boundaries
		//if apps run into issues, we will disable the next line
		#define BT_USE_SSE_IN_API
        #ifdef BT_USE_SSE
            // include appropriate SSE level
            #if defined (__SSE4_1__)
                #include <smmintrin.h>
            #elif defined (__SSSE3__)
                #include <tmmintrin.h>
            #elif defined (__SSE3__)
                #include <pmmintrin.h>
            #else
                #include <emmintrin.h>
            #endif
        #endif //BT_USE_SSE
    #elif defined( __ARM_NEON__ )
        #ifdef __clang__
            #define BT_USE_NEON 1
			#define BT_USE_SIMD_VECTOR3
		
            #if defined BT_USE_NEON && defined (__clang__)
                #include <arm_neon.h>
            #endif//BT_USE_NEON
       #endif //__clang__
    #endif//__arm__

	#define SIMD_FORCE_INLINE inline __attribute__ ((always_inline))
///@todo: check out alignment methods for other platforms/compilers
	#define ATTRIBUTE_ALIGNED16(a) a __attribute__ ((aligned (16)))
	#define ATTRIBUTE_ALIGNED64(a) a __attribute__ ((aligned (64)))
	#define ATTRIBUTE_ALIGNED128(a) a __attribute__ ((aligned (128)))
	#ifndef assert
	#include <assert.h>
	#endif

	#if defined(DEBUG) || defined (_DEBUG)
	 #if defined (__i386__) || defined (__x86_64__)
	#include <stdio.h>
	 #define btAssert(x)\
	{\
	if(!(x))\
	{\
		printf("Assert %s in line %d, file %s\n",#x, __LINE__, __FILE__);\
		asm volatile ("int3");\
	}\
	}
	#else//defined (__i386__) || defined (__x86_64__)
		#define btAssert assert
	#endif//defined (__i386__) || defined (__x86_64__)
	#else//defined(DEBUG) || defined (_DEBUG)
		#define btAssert(x)
	#endif//defined(DEBUG) || defined (_DEBUG)

	//btFullAssert is optional, slows down a lot
	#define btFullAssert(x)
	#define btLikely(_c)  _c
	#define btUnlikely(_c) _c

#else

		#define SIMD_FORCE_INLINE inline
		///@todo: check out alignment methods for other platforms/compilers
		///#define ATTRIBUTE_ALIGNED16(a) a __attribute__ ((aligned (16)))
		///#define ATTRIBUTE_ALIGNED64(a) a __attribute__ ((aligned (64)))
		///#define ATTRIBUTE_ALIGNED128(a) a __attribute__ ((aligned (128)))
		#define ATTRIBUTE_ALIGNED16(a) a
		#define ATTRIBUTE_ALIGNED64(a) a
		#define ATTRIBUTE_ALIGNED128(a) a
		#ifndef assert
		#include <assert.h>
		#endif

#if defined(DEBUG) || defined (_DEBUG)
		#define btAssert assert
#else
		#define btAssert(x)
#endif

		//btFullAssert is optional, slows down a lot
		#define btFullAssert(x)
		#define btLikely(_c)  _c
		#define btUnlikely(_c) _c
#endif //__APPLE__ 

#endif // LIBSPE2

#endif	//__CELLOS_LV2__
#endif


///The btScalar type abstracts floating point numbers, to easily switch between double and single floating point precision.
#if defined(BT_USE_DOUBLE_PRECISION)

typedef double btScalar;
//this number could be bigger in double precision
#define BT_LARGE_FLOAT 1e30
#else

typedef float btScalar;
//keep BT_LARGE_FLOAT*BT_LARGE_FLOAT < FLT_MAX
#define BT_LARGE_FLOAT 1e18f
#endif

#ifdef BT_USE_SSE
typedef __m128 btSimdFloat4;
#endif//BT_USE_SSE

#if defined (BT_USE_SSE)
//#if defined BT_USE_SSE_IN_API && defined (BT_USE_SSE)
#ifdef _WIN32

#ifndef BT_NAN
static int btNanMask = 0x7F800001;
#define BT_NAN (*(float*)&btNanMask)
#endif

#ifndef BT_INFINITY
static  int btInfinityMask = 0x7F800000;
#define BT_INFINITY (*(float*)&btInfinityMask)
inline int btGetInfinityMask()//suppress stupid compiler warning
{
	return btInfinityMask;
}
#endif

//use this, in case there are clashes (such as xnamath.h)
#ifndef BT_NO_SIMD_OPERATOR_OVERLOADS
inline __m128 operator + (const __m128 A, const __m128 B)
{
    return _mm_add_ps(A, B);
}

inline __m128 operator - (const __m128 A, const __m128 B)
{
    return _mm_sub_ps(A, B);
}

inline __m128 operator * (const __m128 A, const __m128 B)
{
    return _mm_mul_ps(A, B);
}
#endif //BT_NO_SIMD_OPERATOR_OVERLOADS

#define btCastfTo128i(a) (_mm_castps_si128(a))
#define btCastfTo128d(a) (_mm_castps_pd(a))
#define btCastiTo128f(a) (_mm_castsi128_ps(a))
#define btCastdTo128f(a) (_mm_castpd_ps(a))
#define btCastdTo128i(a) (_mm_castpd_si128(a))
#define btAssign128(r0,r1,r2,r3) _mm_setr_ps(r0,r1,r2,r3)

#else//_WIN32

#define btCastfTo128i(a) ((__m128i)(a))
#define btCastfTo128d(a) ((__m128d)(a))
#define btCastiTo128f(a)  ((__m128) (a))
#define btCastdTo128f(a) ((__m128) (a))
#define btCastdTo128i(a) ((__m128i)(a))
#define btAssign128(r0,r1,r2,r3) (__m128){r0,r1,r2,r3}
#define BT_INFINITY INFINITY
#define BT_NAN NAN
#endif//_WIN32
#else

#ifdef BT_USE_NEON
	#include <arm_neon.h>

	typedef float32x4_t btSimdFloat4;
	#define BT_INFINITY INFINITY
	#define BT_NAN NAN
	#define btAssign128(r0,r1,r2,r3) (float32x4_t){r0,r1,r2,r3}
#else//BT_USE_NEON

	#ifndef BT_INFINITY
		struct btInfMaskConverter
		{
		        union {
		                float mask;
		                int intmask;
		        };
		        btInfMaskConverter(int mask=0x7F800000)
		        :intmask(mask)
		        {
		        }
		};
		static btInfMaskConverter btInfinityMask = 0x7F800000;
		#define BT_INFINITY (btInfinityMask.mask)
		inline int btGetInfinityMask()//suppress stupid compiler warning
		{
		        return btInfinityMask.intmask;
		}
	#endif
#endif//BT_USE_NEON

#endif //BT_USE_SSE

#ifdef BT_USE_NEON
#include <arm_neon.h>

typedef float32x4_t btSimdFloat4;
#define BT_INFINITY INFINITY
#define BT_NAN NAN
#define btAssign128(r0,r1,r2,r3) (float32x4_t){r0,r1,r2,r3}
#endif





#define BT_DECLARE_ALIGNED_ALLOCATOR() \
   SIMD_FORCE_INLINE void* operator new(size_t sizeInBytes)   { return btAlignedAlloc(sizeInBytes,16); }   \
   SIMD_FORCE_INLINE void  operator delete(void* ptr)         { btAlignedFree(ptr); }   \
   SIMD_FORCE_INLINE void* operator new(size_t, void* ptr)   { return ptr; }   \
   SIMD_FORCE_INLINE void  operator delete(void*, void*)      { }   \
   SIMD_FORCE_INLINE void* operator new[](size_t sizeInBytes)   { return btAlignedAlloc(sizeInBytes,16); }   \
   SIMD_FORCE_INLINE void  operator delete[](void* ptr)         { btAlignedFree(ptr); }   \
   SIMD_FORCE_INLINE void* operator new[](size_t, void* ptr)   { return ptr; }   \
   SIMD_FORCE_INLINE void  operator delete[](void*, void*)      { }   \



#if defined(BT_USE_DOUBLE_PRECISION) || defined(BT_FORCE_DOUBLE_FUNCTIONS)
		
SIMD_FORCE_INLINE btScalar btSqrt(btScalar x) { return sqrt(x); }
SIMD_FORCE_INLINE btScalar btFabs(btScalar x) { return fabs(x); }
SIMD_FORCE_INLINE btScalar btCos(btScalar x) { return cos(x); }
SIMD_FORCE_INLINE btScalar btSin(btScalar x) { return sin(x); }
SIMD_FORCE_INLINE btScalar btTan(btScalar x) { return tan(x); }
SIMD_FORCE_INLINE btScalar btAcos(btScalar x) { if (x<btScalar(-1))	x=btScalar(-1); if (x>btScalar(1))	x=btScalar(1); return acos(x); }
SIMD_FORCE_INLINE btScalar btAsin(btScalar x) { if (x<btScalar(-1))	x=btScalar(-1); if (x>btScalar(1))	x=btScalar(1); return asin(x); }
SIMD_FORCE_INLINE btScalar btAtan(btScalar x) { return atan(x); }
SIMD_FORCE_INLINE btScalar btAtan2(btScalar x, btScalar y) { return atan2(x, y); }
SIMD_FORCE_INLINE btScalar btExp(btScalar x) { return exp(x); }
SIMD_FORCE_INLINE btScalar btLog(btScalar x) { return log(x); }
SIMD_FORCE_INLINE btScalar btPow(btScalar x,btScalar y) { return pow(x,y); }
SIMD_FORCE_INLINE btScalar btFmod(btScalar x,btScalar y) { return fmod(x,y); }

#else
		
SIMD_FORCE_INLINE btScalar btSqrt(btScalar y) 
{ 
#ifdef USE_APPROXIMATION
#ifdef __LP64__
    float xhalf = 0.5f*y;
    int i = *(int*)&y;
    i = 0x5f375a86 - (i>>1);
    y = *(float*)&i;
    y = y*(1.5f - xhalf*y*y);
    y = y*(1.5f - xhalf*y*y);
    y = y*(1.5f - xhalf*y*y);
    y=1/y;
    return y;
#else
    double x, z, tempf;
    unsigned long *tfptr = ((unsigned long *)&tempf) + 1;
    tempf = y;
    *tfptr = (0xbfcdd90a - *tfptr)>>1; /* estimate of 1/sqrt(y) */
    x =  tempf;
    z =  y*btScalar(0.5);
    x = (btScalar(1.5)*x)-(x*x)*(x*z);         /* iteration formula     */
    x = (btScalar(1.5)*x)-(x*x)*(x*z);
    x = (btScalar(1.5)*x)-(x*x)*(x*z);
    x = (btScalar(1.5)*x)-(x*x)*(x*z);
    x = (btScalar(1.5)*x)-(x*x)*(x*z);
    return x*y;
#endif
#else
	return sqrtf(y); 
#endif
}
SIMD_FORCE_INLINE btScalar btFabs(btScalar x) { return fabsf(x); }
SIMD_FORCE_INLINE btScalar btCos(btScalar x) { return cosf(x); }
SIMD_FORCE_INLINE btScalar btSin(btScalar x) { return sinf(x); }
SIMD_FORCE_INLINE btScalar btTan(btScalar x) { return tanf(x); }
SIMD_FORCE_INLINE btScalar btAcos(btScalar x) { 
	if (x<btScalar(-1))	
		x=btScalar(-1); 
	if (x>btScalar(1))	
		x=btScalar(1);
	return acosf(x); 
}
SIMD_FORCE_INLINE btScalar btAsin(btScalar x) { 
	if (x<btScalar(-1))	
		x=btScalar(-1); 
	if (x>btScalar(1))	
		x=btScalar(1);
	return asinf(x); 
}
SIMD_FORCE_INLINE btScalar btAtan(btScalar x) { return atanf(x); }
SIMD_FORCE_INLINE btScalar btAtan2(btScalar x, btScalar y) { return atan2f(x, y); }
SIMD_FORCE_INLINE btScalar btExp(btScalar x) { return expf(x); }
SIMD_FORCE_INLINE btScalar btLog(btScalar x) { return logf(x); }
SIMD_FORCE_INLINE btScalar btPow(btScalar x,btScalar y) { return powf(x,y); }
SIMD_FORCE_INLINE btScalar btFmod(btScalar x,btScalar y) { return fmodf(x,y); }
	
#endif

#define SIMD_PI           btScalar(3.1415926535897932384626433832795029)
#define SIMD_2_PI         (btScalar(2.0) * SIMD_PI)
#define SIMD_HALF_PI      (SIMD_PI * btScalar(0.5))
#define SIMD_RADS_PER_DEG (SIMD_2_PI / btScalar(360.0))
#define SIMD_DEGS_PER_RAD  (btScalar(360.0) / SIMD_2_PI)
#define SIMDSQRT12 btScalar(0.7071067811865475244008443621048490)

#define btRecipSqrt(x) ((btScalar)(btScalar(1.0)/btSqrt(btScalar(x))))		/* reciprocal square root */
#define btRecip(x) (btScalar(1.0)/btScalar(x))

#ifdef BT_USE_DOUBLE_PRECISION
#define SIMD_EPSILON      DBL_EPSILON
#define SIMD_INFINITY     DBL_MAX
#define BT_ONE			1.0
#define BT_ZERO			0.0
#define BT_TWO			2.0
#define BT_HALF			0.5
#else
#define SIMD_EPSILON      FLT_EPSILON
#define SIMD_INFINITY     FLT_MAX
#define BT_ONE			1.0f
#define BT_ZERO			0.0f
#define BT_TWO			2.0f
#define BT_HALF			0.5f
#endif

SIMD_FORCE_INLINE btScalar btAtan2Fast(btScalar y, btScalar x) 
{
	btScalar coeff_1 = SIMD_PI / 4.0f;
	btScalar coeff_2 = 3.0f * coeff_1;
	btScalar abs_y = btFabs(y);
	btScalar angle;
	if (x >= 0.0f) {
		btScalar r = (x - abs_y) / (x + abs_y);
		angle = coeff_1 - coeff_1 * r;
	} else {
		btScalar r = (x + abs_y) / (abs_y - x);
		angle = coeff_2 - coeff_1 * r;
	}
	return (y < 0.0f) ? -angle : angle;
}

SIMD_FORCE_INLINE bool      btFuzzyZero(btScalar x) { return btFabs(x) < SIMD_EPSILON; }

SIMD_FORCE_INLINE bool	btEqual(btScalar a, btScalar eps) {
	return (((a) <= eps) && !((a) < -eps));
}
SIMD_FORCE_INLINE bool	btGreaterEqual (btScalar a, btScalar eps) {
	return (!((a) <= eps));
}


SIMD_FORCE_INLINE int       btIsNegative(btScalar x) {
    return x < btScalar(0.0) ? 1 : 0;
}

SIMD_FORCE_INLINE btScalar btRadians(btScalar x) { return x * SIMD_RADS_PER_DEG; }
SIMD_FORCE_INLINE btScalar btDegrees(btScalar x) { return x * SIMD_DEGS_PER_RAD; }

#define BT_DECLARE_HANDLE(name) typedef struct name##__ { int unused; } *name

#ifndef btFsel
SIMD_FORCE_INLINE btScalar btFsel(btScalar a, btScalar b, btScalar c)
{
	return a >= 0 ? b : c;
}
#endif
#define btFsels(a,b,c) (btScalar)btFsel(a,b,c)


SIMD_FORCE_INLINE bool btMachineIsLittleEndian()
{
   long int i = 1;
   const char *p = (const char *) &i;
   if (p[0] == 1)  // Lowest address contains the least significant byte
	   return true;
   else
	   return false;
}



///btSelect avoids branches, which makes performance much better for consoles like Playstation 3 and XBox 360
///Thanks Phil Knight. See also http://www.cellperformance.com/articles/2006/04/more_techniques_for_eliminatin_1.html
SIMD_FORCE_INLINE unsigned btSelect(unsigned condition, unsigned valueIfConditionNonZero, unsigned valueIfConditionZero) 
{
    // Set testNz to 0xFFFFFFFF if condition is nonzero, 0x00000000 if condition is zero
    // Rely on positive value or'ed with its negative having sign bit on
    // and zero value or'ed with its negative (which is still zero) having sign bit off 
    // Use arithmetic shift right, shifting the sign bit through all 32 bits
    unsigned testNz = (unsigned)(((int)condition | -(int)condition) >> 31);
    unsigned testEqz = ~testNz;
    return ((valueIfConditionNonZero & testNz) | (valueIfConditionZero & testEqz)); 
}
SIMD_FORCE_INLINE int btSelect(unsigned condition, int valueIfConditionNonZero, int valueIfConditionZero)
{
    unsigned testNz = (unsigned)(((int)condition | -(int)condition) >> 31);
    unsigned testEqz = ~testNz; 
    return static_cast<int>((valueIfConditionNonZero & testNz) | (valueIfConditionZero & testEqz));
}
SIMD_FORCE_INLINE float btSelect(unsigned condition, float valueIfConditionNonZero, float valueIfConditionZero)
{
#ifdef BT_HAVE_NATIVE_FSEL
    return (float)btFsel((btScalar)condition - btScalar(1.0f), valueIfConditionNonZero, valueIfConditionZero);
#else
    return (condition != 0) ? valueIfConditionNonZero : valueIfConditionZero; 
#endif
}

template<typename T> SIMD_FORCE_INLINE void btSwap(T& a, T& b)
{
	T tmp = a;
	a = b;
	b = tmp;
}


//PCK: endian swapping functions
SIMD_FORCE_INLINE unsigned btSwapEndian(unsigned val)
{
	return (((val & 0xff000000) >> 24) | ((val & 0x00ff0000) >> 8) | ((val & 0x0000ff00) << 8)  | ((val & 0x000000ff) << 24));
}

SIMD_FORCE_INLINE unsigned short btSwapEndian(unsigned short val)
{
	return static_cast<unsigned short>(((val & 0xff00) >> 8) | ((val & 0x00ff) << 8));
}

SIMD_FORCE_INLINE unsigned btSwapEndian(int val)
{
	return btSwapEndian((unsigned)val);
}

SIMD_FORCE_INLINE unsigned short btSwapEndian(short val)
{
	return btSwapEndian((unsigned short) val);
}

///btSwapFloat uses using char pointers to swap the endianness
////btSwapFloat/btSwapDouble will NOT return a float, because the machine might 'correct' invalid floating point values
///Not all values of sign/exponent/mantissa are valid floating point numbers according to IEEE 754. 
///When a floating point unit is faced with an invalid value, it may actually change the value, or worse, throw an exception. 
///In most systems, running user mode code, you wouldn't get an exception, but instead the hardware/os/runtime will 'fix' the number for you. 
///so instead of returning a float/double, we return integer/long long integer
SIMD_FORCE_INLINE unsigned int  btSwapEndianFloat(float d)
{
    unsigned int a = 0;
    unsigned char *dst = (unsigned char *)&a;
    unsigned char *src = (unsigned char *)&d;

    dst[0] = src[3];
    dst[1] = src[2];
    dst[2] = src[1];
    dst[3] = src[0];
    return a;
}

// unswap using char pointers
SIMD_FORCE_INLINE float btUnswapEndianFloat(unsigned int a) 
{
    float d = 0.0f;
    unsigned char *src = (unsigned char *)&a;
    unsigned char *dst = (unsigned char *)&d;

    dst[0] = src[3];
    dst[1] = src[2];
    dst[2] = src[1];
    dst[3] = src[0];

    return d;
}


// swap using char pointers
SIMD_FORCE_INLINE void  btSwapEndianDouble(double d, unsigned char* dst)
{
    unsigned char *src = (unsigned char *)&d;

    dst[0] = src[7];
    dst[1] = src[6];
    dst[2] = src[5];
    dst[3] = src[4];
    dst[4] = src[3];
    dst[5] = src[2];
    dst[6] = src[1];
    dst[7] = src[0];

}

// unswap using char pointers
SIMD_FORCE_INLINE double btUnswapEndianDouble(const unsigned char *src) 
{
    double d = 0.0;
    unsigned char *dst = (unsigned char *)&d;

    dst[0] = src[7];
    dst[1] = src[6];
    dst[2] = src[5];
    dst[3] = src[4];
    dst[4] = src[3];
    dst[5] = src[2];
    dst[6] = src[1];
    dst[7] = src[0];

	return d;
}

template<typename T>
SIMD_FORCE_INLINE void btSetZero(T* a, int n)
{
  T* acurr = a;
  size_t ncurr = n;
  while (ncurr > 0) 
  {
    *(acurr++) = 0;
    --ncurr;
  }
}


SIMD_FORCE_INLINE btScalar btLargeDot(const btScalar *a, const btScalar *b, int n)
{  
  btScalar p0,q0,m0,p1,q1,m1,sum;
  sum = 0;
  n -= 2;
  while (n >= 0) {
    p0 = a[0]; q0 = b[0];
    m0 = p0 * q0;
    p1 = a[1]; q1 = b[1];
    m1 = p1 * q1;
    sum += m0;
    sum += m1;
    a += 2;
    b += 2;
    n -= 2;
  }
  n += 2;
  while (n > 0) {
    sum += (*a) * (*b);
    a++;
    b++;
    n--;
  }
  return sum;
}


// returns normalized value in range [-SIMD_PI, SIMD_PI]
SIMD_FORCE_INLINE btScalar btNormalizeAngle(btScalar angleInRadians) 
{
	angleInRadians = btFmod(angleInRadians, SIMD_2_PI);
	if(angleInRadians < -SIMD_PI)
	{
		return angleInRadians + SIMD_2_PI;
	}
	else if(angleInRadians > SIMD_PI)
	{
		return angleInRadians - SIMD_2_PI;
	}
	else
	{
		return angleInRadians;
	}
}



///rudimentary class to provide type info
struct btTypedObject
{
	btTypedObject(int objectType)
		:m_objectType(objectType)
	{
	}
	int	m_objectType;
	inline int getObjectType() const
	{
		return m_objectType;
	}
};


  
///align a pointer to the provided alignment, upwards
template <typename T>T* btAlignPointer(T* unalignedPtr, size_t alignment)
{
		
	struct btConvertPointerSizeT
	{
		union 
		{
				T* ptr;
				size_t integer;
		};
	};
    btConvertPointerSizeT converter;
    
    
	const size_t bit_mask = ~(alignment - 1);
    converter.ptr = unalignedPtr;
	converter.integer += alignment-1;
	converter.integer &= bit_mask;
	return converter.ptr;
}


#endif //BT_SCALAR_H