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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 1.108 by root, Wed May 26 19:11:43 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}
459}; 481};
460 482
461template<class generator> 483template<class generator>
462struct random_number_generator : generator 484struct random_number_generator : generator
463{ 485{
464 // uniform distribution, 0 .. max (0, num - 1) 486 // uniform distribution, [0 .. num - 1]
465 uint32_t operator ()(uint32_t num) 487 uint32_t operator ()(uint32_t num)
466 { 488 {
467 return !is_constant (num) ? get_range (num) // non-constant 489 return !is_constant (num) ? get_range (num) // non-constant
468 : num & (num - 1) ? (this->next () * (uint64_t)num) >> 32U // constant, non-power-of-two 490 : num & (num - 1) ? (this->next () * (uint64_t)num) >> 32U // constant, non-power-of-two
469 : this->next () & (num - 1); // constant, power-of-two 491 : this->next () & (num - 1); // constant, power-of-two
470 } 492 }
471 493
472 // return a number within (min .. max) 494 // return a number within the closed interval [min .. max]
473 int operator () (int r_min, int r_max) 495 int operator () (int r_min, int r_max)
474 { 496 {
475 return is_constant (r_min) && is_constant (r_max) && r_min <= r_max 497 return is_constant (r_min <= r_max) && r_min <= r_max
476 ? r_min + operator ()(r_max - r_min + 1) 498 ? r_min + operator ()(r_max - r_min + 1)
477 : get_range (r_min, r_max); 499 : get_range (r_min, r_max);
478 } 500 }
479 501
502 // return a number within the half-open interval [0..1[
480 double operator ()() 503 double operator ()()
481 { 504 {
482 return this->next () / (double)0xFFFFFFFFU; 505 return this->next () / (double)0x100000000ULL;
483 } 506 }
484 507
485protected: 508protected:
486 uint32_t get_range (uint32_t r_max); 509 uint32_t get_range (uint32_t r_max);
487 int get_range (int r_min, int r_max); 510 int get_range (int r_min, int r_max);
559typedef refptr<maptile> maptile_ptr; 582typedef refptr<maptile> maptile_ptr;
560typedef refptr<object> object_ptr; 583typedef refptr<object> object_ptr;
561typedef refptr<archetype> arch_ptr; 584typedef refptr<archetype> arch_ptr;
562typedef refptr<client> client_ptr; 585typedef refptr<client> client_ptr;
563typedef refptr<player> player_ptr; 586typedef refptr<player> player_ptr;
587typedef refptr<region> region_ptr;
564 588
565#define STRHSH_NULL 2166136261 589#define STRHSH_NULL 2166136261
566 590
567static inline uint32_t 591static inline uint32_t
568strhsh (const char *s) 592strhsh (const char *s)
573 // FNV-1a is faster on many cpus because the multiplication 597 // FNV-1a is faster on many cpus because the multiplication
574 // runs concurrently with the looping logic. 598 // runs concurrently with the looping logic.
575 uint32_t hash = STRHSH_NULL; 599 uint32_t hash = STRHSH_NULL;
576 600
577 while (*s) 601 while (*s)
578 hash = (hash ^ *s++) * 16777619; 602 hash = (hash ^ *s++) * 16777619U;
579 603
580 return hash; 604 return hash;
581} 605}
582 606
583static inline uint32_t 607static inline uint32_t
584memhsh (const char *s, size_t len) 608memhsh (const char *s, size_t len)
585{ 609{
586 uint32_t hash = STRHSH_NULL; 610 uint32_t hash = STRHSH_NULL;
587 611
588 while (len--) 612 while (len--)
589 hash = (hash ^ *s++) * 16777619; 613 hash = (hash ^ *s++) * 16777619U;
590 614
591 return hash; 615 return hash;
592} 616}
593 617
594struct str_hash 618struct str_hash

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