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Comparing deliantra/server/include/util.h (file contents):
Revision 1.101 by root, Wed Apr 28 19:49:50 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// could use the sizeof (arr) /( sizeof (arr [0]) here, but C++ is 60#if cplusplus_does_not_suck
61// much more obfuscated... :) 61// does not work for local types (http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2008/n2657.htm)
62
63template<typename T, int N> 62template<typename T, int N>
64inline int array_length (const T (&arr)[N]) 63static inline int array_length (const T (&arr)[N])
65{ 64{
66 return N; 65 return N;
67} 66}
67#else
68#define array_length(name) (sizeof (name) / sizeof (name [0]))
69#endif
68 70
69// very ugly macro that basically declares and initialises a variable 71// very ugly macro that basically declares and initialises a variable
70// that is in scope for the next statement only 72// that is in scope for the next statement only
71// 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
72// (note: works great for pointers) 74// (note: works great for pointers)
… …
102// sign returns -1 or +1 104// sign returns -1 or +1
103template<typename T> 105template<typename T>
104static inline T sign (T v) { return v < 0 ? -1 : +1; } 106static inline T sign (T v) { return v < 0 ? -1 : +1; }
105// relies on 2c representation 107// relies on 2c representation
106template<> 108template<>
107inline 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); }
108 114
109// sign0 returns -1, 0 or +1 115// sign0 returns -1, 0 or +1
110template<typename T> 116template<typename T>
111static inline T sign0 (T v) { return v ? sign (v) : 0; } 117static inline T sign0 (T v) { return v ? sign (v) : 0; }
112 118
… …
117// div, with correct rounding (< 0.5 downwards, >=0.5 upwards) 123// div, with correct rounding (< 0.5 downwards, >=0.5 upwards)
118template<typename T> static inline T div (T val, T div) 124template<typename T> static inline T div (T val, T div)
119{ 125{
120 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;
121} 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
122// div, round-up 132// div, round-up
123template<typename T> static inline T div_ru (T val, T div) 133template<typename T> static inline T div_ru (T val, T div)
124{ 134{
125 return expect_false (val < 0) ? - ((-val ) / div) : (val + div - 1) / div; 135 return expect_false (val < 0) ? - ((-val ) / div) : (val + div - 1) / div;
126} 136}
… …
419 { 429 {
420 p->~Tp (); 430 p->~Tp ();
421 } 431 }
422}; 432};
423 433
424// P. L'Ecuyer, “Maximally Equidistributed Combined Tausworthe Generators”, Mathematics of Computation, 65, 213 (1996), 203–213.
425// http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme.ps
426// http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme2.ps
427struct tausworthe_random_generator
428{
429 uint32_t state [4];
430
431 void operator =(const tausworthe_random_generator &src)
432 {
433 state [0] = src.state [0];
434 state [1] = src.state [1];
435 state [2] = src.state [2];
436 state [3] = src.state [3];
437 }
438
439 void seed (uint32_t seed);
440 uint32_t next ();
441};
442
443// Xorshift RNGs, George Marsaglia
444// http://www.jstatsoft.org/v08/i14/paper
445// this one is about 40% faster than the tausworthe one above (i.e. not much),
446// despite the inlining, and has the issue of only creating 2**32-1 numbers.
447// see also http://www.iro.umontreal.ca/~lecuyer/myftp/papers/xorshift.pdf
448struct xorshift_random_generator
449{
450 uint32_t x, y;
451
452 void operator =(const xorshift_random_generator &src)
453 {
454 x = src.x;
455 y = src.y;
456 }
457
458 void seed (uint32_t seed)
459 {
460 x = seed;
461 y = seed * 69069U;
462 }
463
464 uint32_t next ()
465 {
466 uint32_t t = x ^ (x << 10);
467 x = y;
468 y = y ^ (y >> 13) ^ t ^ (t >> 10);
469 return y;
470 }
471};
472
473template<class generator>
474struct random_number_generator : generator
475{
476 // uniform distribution, 0 .. max (0, num - 1)
477 uint32_t operator ()(uint32_t num)
478 {
479 return !is_constant (num) ? get_range (num) // non-constant
480 : num & (num - 1) ? (this->next () * (uint64_t)num) >> 32U // constant, non-power-of-two
481 : this->next () & (num - 1); // constant, power-of-two
482 }
483
484 // return a number within the closed interval [min .. max]
485 int operator () (int r_min, int r_max)
486 {
487 return is_constant (r_min) && is_constant (r_max) && r_min <= r_max
488 ? r_min + operator ()(r_max - r_min + 1)
489 : get_range (r_min, r_max);
490 }
491
492 // return a number within the closed interval [0..1]
493 double operator ()()
494 {
495 return this->next () / (double)0xFFFFFFFFU;
496 }
497
498protected:
499 uint32_t get_range (uint32_t r_max);
500 int get_range (int r_min, int r_max);
501};
502
503typedef random_number_generator<tausworthe_random_generator> rand_gen;
504
505extern rand_gen rndm, rmg_rndm;
506
507INTERFACE_CLASS (attachable) 434INTERFACE_CLASS (attachable)
508struct refcnt_base 435struct refcnt_base
509{ 436{
510 typedef int refcnt_t; 437 typedef int refcnt_t;
511 mutable refcnt_t ACC (RW, refcnt); 438 mutable refcnt_t ACC (RW, refcnt);
… …
572typedef refptr<maptile> maptile_ptr; 499typedef refptr<maptile> maptile_ptr;
573typedef refptr<object> object_ptr; 500typedef refptr<object> object_ptr;
574typedef refptr<archetype> arch_ptr; 501typedef refptr<archetype> arch_ptr;
575typedef refptr<client> client_ptr; 502typedef refptr<client> client_ptr;
576typedef refptr<player> player_ptr; 503typedef refptr<player> player_ptr;
504typedef refptr<region> region_ptr;
577 505
578#define STRHSH_NULL 2166136261 506#define STRHSH_NULL 2166136261
579 507
580static inline uint32_t 508static inline uint32_t
581strhsh (const char *s) 509strhsh (const char *s)

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