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Comparing deliantra/server/include/util.h (file contents):
Revision 1.97 by root, Fri Mar 26 01:04:44 2010 UTC vs.
Revision 1.110 by root, Fri Jul 2 02:00:47 2010 UTC

… …
55#endif 55#endif
56 56
57// use C0X decltype for auto declarations until ISO C++ sanctifies them (if ever) 57// use C0X decltype for auto declarations until ISO C++ sanctifies them (if ever)
58#define auto(var,expr) decltype(expr) var = (expr) 58#define auto(var,expr) decltype(expr) var = (expr)
59 59
60#if cplusplus_does_not_suck
61// does not work for local types (http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2008/n2657.htm)
62template<typename T, int N>
63static inline int array_length (const T (&arr)[N])
64{
65 return N;
66}
67#else
68#define array_length(name) (sizeof (name) / sizeof (name [0]))
69#endif
70
60// very ugly macro that basically declares and initialises a variable 71// very ugly macro that basically declares and initialises a variable
61// that is in scope for the next statement only 72// that is in scope for the next statement only
62// works only for stuff that can be assigned 0 and converts to false 73// works only for stuff that can be assigned 0 and converts to false
63// (note: works great for pointers) 74// (note: works great for pointers)
64// most ugly macro I ever wrote 75// most ugly macro I ever wrote
… …
93// sign returns -1 or +1 104// sign returns -1 or +1
94template<typename T> 105template<typename T>
95static inline T sign (T v) { return v < 0 ? -1 : +1; } 106static inline T sign (T v) { return v < 0 ? -1 : +1; }
96// relies on 2c representation 107// relies on 2c representation
97template<> 108template<>
98inline sint8 sign (sint8 v) { return 1 - (sint8 (uint8 (v) >> 7) * 2); } 109inline sint8 sign (sint8 v) { return 1 - (sint8 (uint8 (v) >> 7) * 2); }
110template<>
111inline sint16 sign (sint16 v) { return 1 - (sint16 (uint16 (v) >> 15) * 2); }
112template<>
113inline sint32 sign (sint32 v) { return 1 - (sint32 (uint32 (v) >> 31) * 2); }
99 114
100// sign0 returns -1, 0 or +1 115// sign0 returns -1, 0 or +1
101template<typename T> 116template<typename T>
102static inline T sign0 (T v) { return v ? sign (v) : 0; } 117static inline T sign0 (T v) { return v ? sign (v) : 0; }
118
119template<typename T, typename U>
120static inline T copysign (T a, U b) { return a > 0 ? b : -b; }
103 121
104// div* only work correctly for div > 0 122// div* only work correctly for div > 0
105// div, with correct rounding (< 0.5 downwards, >=0.5 upwards) 123// div, with correct rounding (< 0.5 downwards, >=0.5 upwards)
106template<typename T> static inline T div (T val, T div) 124template<typename T> static inline T div (T val, T div)
107{ 125{
108 return expect_false (val < 0) ? - ((-val + (div - 1) / 2) / div) : (val + div / 2) / div; 126 return expect_false (val < 0) ? - ((-val + (div - 1) / 2) / div) : (val + div / 2) / div;
109} 127}
128
129template<> inline float div (float val, float div) { return val / div; }
130template<> inline double div (double val, double div) { return val / div; }
131
110// div, round-up 132// div, round-up
111template<typename T> static inline T div_ru (T val, T div) 133template<typename T> static inline T div_ru (T val, T div)
112{ 134{
113 return expect_false (val < 0) ? - ((-val ) / div) : (val + div - 1) / div; 135 return expect_false (val < 0) ? - ((-val ) / div) : (val + div - 1) / div;
114} 136}
… …
407 { 429 {
408 p->~Tp (); 430 p->~Tp ();
409 } 431 }
410}; 432};
411 433
412// P. L'Ecuyer, “Maximally Equidistributed Combined Tausworthe Generators”, Mathematics of Computation, 65, 213 (1996), 203–213.
413// http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme.ps
414// http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme2.ps
415struct tausworthe_random_generator
416{
417 uint32_t state [4];
418
419 void operator =(const tausworthe_random_generator &src)
420 {
421 state [0] = src.state [0];
422 state [1] = src.state [1];
423 state [2] = src.state [2];
424 state [3] = src.state [3];
425 }
426
427 void seed (uint32_t seed);
428 uint32_t next ();
429};
430
431// Xorshift RNGs, George Marsaglia
432// http://www.jstatsoft.org/v08/i14/paper
433// this one is about 40% faster than the tausworthe one above (i.e. not much),
434// despite the inlining, and has the issue of only creating 2**32-1 numbers.
435// see also http://www.iro.umontreal.ca/~lecuyer/myftp/papers/xorshift.pdf
436struct xorshift_random_generator
437{
438 uint32_t x, y;
439
440 void operator =(const xorshift_random_generator &src)
441 {
442 x = src.x;
443 y = src.y;
444 }
445
446 void seed (uint32_t seed)
447 {
448 x = seed;
449 y = seed * 69069U;
450 }
451
452 uint32_t next ()
453 {
454 uint32_t t = x ^ (x << 10);
455 x = y;
456 y = y ^ (y >> 13) ^ t ^ (t >> 10);
457 return y;
458 }
459};
460
461template<class generator>
462struct random_number_generator : generator
463{
464 // uniform distribution, 0 .. max (0, num - 1)
465 uint32_t operator ()(uint32_t num)
466 {
467 return !is_constant (num) ? get_range (num) // non-constant
468 : num & (num - 1) ? (this->next () * (uint64_t)num) >> 32U // constant, non-power-of-two
469 : this->next () & (num - 1); // constant, power-of-two
470 }
471
472 // return a number within (min .. max)
473 int operator () (int r_min, int r_max)
474 {
475 return is_constant (r_min) && is_constant (r_max) && r_min <= r_max
476 ? r_min + operator ()(r_max - r_min + 1)
477 : get_range (r_min, r_max);
478 }
479
480 double operator ()()
481 {
482 return this->next () / (double)0xFFFFFFFFU;
483 }
484
485protected:
486 uint32_t get_range (uint32_t r_max);
487 int get_range (int r_min, int r_max);
488};
489
490typedef random_number_generator<tausworthe_random_generator> rand_gen;
491
492extern rand_gen rndm, rmg_rndm;
493
494INTERFACE_CLASS (attachable) 434INTERFACE_CLASS (attachable)
495struct refcnt_base 435struct refcnt_base
496{ 436{
497 typedef int refcnt_t; 437 typedef int refcnt_t;
498 mutable refcnt_t ACC (RW, refcnt); 438 mutable refcnt_t ACC (RW, refcnt);
… …
559typedef refptr<maptile> maptile_ptr; 499typedef refptr<maptile> maptile_ptr;
560typedef refptr<object> object_ptr; 500typedef refptr<object> object_ptr;
561typedef refptr<archetype> arch_ptr; 501typedef refptr<archetype> arch_ptr;
562typedef refptr<client> client_ptr; 502typedef refptr<client> client_ptr;
563typedef refptr<player> player_ptr; 503typedef refptr<player> player_ptr;
504typedef refptr<region> region_ptr;
564 505
565#define STRHSH_NULL 2166136261 506#define STRHSH_NULL 2166136261
566 507
567static inline uint32_t 508static inline uint32_t
568strhsh (const char *s) 509strhsh (const char *s)
… …
573 // FNV-1a is faster on many cpus because the multiplication 514 // FNV-1a is faster on many cpus because the multiplication
574 // runs concurrently with the looping logic. 515 // runs concurrently with the looping logic.
575 uint32_t hash = STRHSH_NULL; 516 uint32_t hash = STRHSH_NULL;
576 517
577 while (*s) 518 while (*s)
578 hash = (hash ^ *s++) * 16777619; 519 hash = (hash ^ *s++) * 16777619U;
579 520
580 return hash; 521 return hash;
581} 522}
582 523
583static inline uint32_t 524static inline uint32_t
584memhsh (const char *s, size_t len) 525memhsh (const char *s, size_t len)
585{ 526{
586 uint32_t hash = STRHSH_NULL; 527 uint32_t hash = STRHSH_NULL;
587 528
588 while (len--) 529 while (len--)
589 hash = (hash ^ *s++) * 16777619; 530 hash = (hash ^ *s++) * 16777619U;
590 531
591 return hash; 532 return hash;
592} 533}
593 534
594struct str_hash 535struct str_hash

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