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Comparing deliantra/server/include/util.h (file contents):
Revision 1.26 by root, Sun Jan 7 02:39:14 2007 UTC vs.
Revision 1.39 by pippijn, Thu Mar 1 12:28:16 2007 UTC

1#ifndef UTIL_H__ 1#ifndef UTIL_H__
2#define UTIL_H__ 2#define UTIL_H__
3
4//#define PREFER_MALLOC
3 5
4#if __GNUC__ >= 3 6#if __GNUC__ >= 3
5# define is_constant(c) __builtin_constant_p (c) 7# define is_constant(c) __builtin_constant_p (c)
6#else 8#else
7# define is_constant(c) 0 9# define is_constant(c) 0
8#endif 10#endif
9 11
10#include <cstddef> 12#include <cstddef>
13#include <cmath>
11#include <new> 14#include <new>
12#include <vector> 15#include <vector>
13 16
14#include <glib.h> 17#include <glib.h>
15 18
… …
24// works only for stuff that can be assigned 0 and converts to false 27// works only for stuff that can be assigned 0 and converts to false
25// (note: works great for pointers) 28// (note: works great for pointers)
26// most ugly macro I ever wrote 29// most ugly macro I ever wrote
27#define declvar(type, name, value) if (type name = 0) { } else if (((name) = (value)), 1) 30#define declvar(type, name, value) if (type name = 0) { } else if (((name) = (value)), 1)
28 31
32// in range including end
33#define IN_RANGE_INC(val,beg,end) \
34 ((unsigned int)(val) - (unsigned int)(beg) <= (unsigned int)(end) - (unsigned int)(beg))
35
36// in range excluding end
37#define IN_RANGE_EXC(val,beg,end) \
38 ((unsigned int)(val) - (unsigned int)(beg) < (unsigned int)(end) - (unsigned int)(beg))
39
40void fork_abort (const char *msg);
41
42// rationale for using (U) not (T) is to reduce signed/unsigned issues,
43// as a is often a constant while b is the variable. it is still a bug, though.
44template<typename T, typename U> static inline T min (T a, U b) { return (U)a < b ? (U)a : b; }
45template<typename T, typename U> static inline T max (T a, U b) { return (U)a > b ? (U)a : b; }
46template<typename T, typename U, typename V> static inline T clamp (T v, U a, V b) { return v < (T)a ? (T)a : v >(T)b ? (T)b : v; }
47
48template<typename T, typename U> static inline void swap (T& a, U& b) { T t=a; a=(T)b; b=(U)t; }
49
50// lots of stuff taken from FXT
51
52/* Rotate right. This is used in various places for checksumming */
53//TODO: that sucks, use a better checksum algo
54static inline uint32_t
55rotate_right (uint32_t c, uint32_t count = 1)
56{
57 return (c << (32 - count)) | (c >> count);
58}
59
60static inline uint32_t
61rotate_left (uint32_t c, uint32_t count = 1)
62{
63 return (c >> (32 - count)) | (c << count);
64}
65
66// Return abs(a-b)
67// Both a and b must not have the most significant bit set
68static inline uint32_t
69upos_abs_diff (uint32_t a, uint32_t b)
70{
71 long d1 = b - a;
72 long d2 = (d1 & (d1 >> 31)) << 1;
73
74 return d1 - d2; // == (b - d) - (a + d);
75}
76
77// Both a and b must not have the most significant bit set
78static inline uint32_t
79upos_min (uint32_t a, uint32_t b)
80{
81 int32_t d = b - a;
82 d &= d >> 31;
83 return a + d;
84}
85
86// Both a and b must not have the most significant bit set
87static inline uint32_t
88upos_max (uint32_t a, uint32_t b)
89{
90 int32_t d = b - a;
91 d &= d >> 31;
92 return b - d;
93}
94
95// this is much faster than crossfires original algorithm
96// on modern cpus
97inline int
98isqrt (int n)
99{
100 return (int)sqrtf ((float)n);
101}
102
103// this is only twice as fast as naive sqrtf (dx*dy+dy*dy)
104#if 0
105// and has a max. error of 6 in the range -100..+100.
106#else
107// and has a max. error of 9 in the range -100..+100.
108#endif
109inline int
110idistance (int dx, int dy)
111{
112 unsigned int dx_ = abs (dx);
113 unsigned int dy_ = abs (dy);
114
115#if 0
116 return dx_ > dy_
117 ? (dx_ * 61685 + dy_ * 26870) >> 16
118 : (dy_ * 61685 + dx_ * 26870) >> 16;
119#else
120 return dx_ + dy_ - min (dx_, dy_) * 5 / 8;
121#endif
122}
123
124/*
125 * absdir(int): Returns a number between 1 and 8, which represent
126 * the "absolute" direction of a number (it actually takes care of
127 * "overflow" in previous calculations of a direction).
128 */
129inline int
130absdir (int d)
131{
132 return ((d - 1) & 7) + 1;
133}
134
29// makes dynamically allocated objects zero-initialised 135// makes dynamically allocated objects zero-initialised
30struct zero_initialised 136struct zero_initialised
31{ 137{
32 void *operator new (size_t s, void *p) 138 void *operator new (size_t s, void *p)
33 { 139 {
… …
74 180
75// for symmetry 181// for symmetry
76template<typename T> 182template<typename T>
77inline void sfree (T *ptr, int n = 1) throw () 183inline void sfree (T *ptr, int n = 1) throw ()
78{ 184{
185#ifdef PREFER_MALLOC
186 free (ptr);
187#else
79 g_slice_free1 (n * sizeof (T), (void *)ptr); 188 g_slice_free1 (n * sizeof (T), (void *)ptr);
189#endif
80} 190}
81 191
82// a STL-compatible allocator that uses g_slice 192// a STL-compatible allocator that uses g_slice
83// boy, this is verbose 193// boy, this is verbose
84template<typename Tp> 194template<typename Tp>
… …
131 void destroy (pointer p) 241 void destroy (pointer p)
132 { 242 {
133 p->~Tp (); 243 p->~Tp ();
134 } 244 }
135}; 245};
246
247// P. L'Ecuyer, “Maximally Equidistributed Combined Tausworthe Generators”, Mathematics of Computation, 65, 213 (1996), 203–213.
248// http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme.ps
249// http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme2.ps
250struct tausworthe_random_generator
251{
252 // generator
253 uint32_t state [4];
254
255 void operator =(const tausworthe_random_generator &src)
256 {
257 state [0] = src.state [0];
258 state [1] = src.state [1];
259 state [2] = src.state [2];
260 state [3] = src.state [3];
261 }
262
263 void seed (uint32_t seed);
264 uint32_t next ();
265
266 // uniform distribution
267 uint32_t operator ()(uint32_t r_max)
268 {
269 return is_constant (r_max)
270 ? this->next () % r_max
271 : get_range (r_max);
272 }
273
274 // return a number within (min .. max)
275 int operator () (int r_min, int r_max)
276 {
277 return is_constant (r_min) && is_constant (r_max)
278 ? r_min + (*this) (max (r_max - r_min + 1, 1))
279 : get_range (r_min, r_max);
280 }
281
282 double operator ()()
283 {
284 return this->next () / (double)0xFFFFFFFFU;
285 }
286
287protected:
288 uint32_t get_range (uint32_t r_max);
289 int get_range (int r_min, int r_max);
290};
291
292typedef tausworthe_random_generator rand_gen;
293
294extern rand_gen rndm;
136 295
137template<class T> 296template<class T>
138struct refptr 297struct refptr
139{ 298{
140 T *p; 299 T *p;
… …
240 } 399 }
241 400
242 void erase (T *obj) 401 void erase (T *obj)
243 { 402 {
244 assert (obj->*index); 403 assert (obj->*index);
245 int pos = obj->*index; 404 unsigned int pos = obj->*index;
246 obj->*index = 0; 405 obj->*index = 0;
247 406
248 if (pos < this->size ()) 407 if (pos < this->size ())
249 { 408 {
250 (*this)[pos - 1] = (*this)[this->size () - 1]; 409 (*this)[pos - 1] = (*this)[this->size () - 1];
… …
258 { 417 {
259 errase (&obj); 418 errase (&obj);
260 } 419 }
261}; 420};
262 421
263template<typename T, typename U> static inline T min (T a, U b) { return a < (T)b ? a : (T)b; }
264template<typename T, typename U> static inline T max (T a, U b) { return a > (T)b ? a : (T)b; }
265template<typename T, typename U, typename V> static inline T clamp (T v, U a, V b) { return v < (T)a ? a : v >(T)b ? b : v; }
266
267template<typename T, typename U> static inline void swap (T& a, U& b) { T t=a; a=(T)b; b=(U)t; }
268
269// basically does what strncpy should do, but appends "..." to strings exceeding length 422// basically does what strncpy should do, but appends "..." to strings exceeding length
270void assign (char *dst, const char *src, int maxlen); 423void assign (char *dst, const char *src, int maxlen);
271 424
272// type-safe version of assign 425// type-safe version of assign
273template<int N> 426template<int N>

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