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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 1.37 by root, Thu Feb 15 15:43:36 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: this sucks, use a better checksum algo
54static inline uint32_t
55rotate_right (uint32_t c)
56{
57 return (c << 31) | (c >> 1);
58}
59
60// Return abs(a-b)
61// Both a and b must not have the most significant bit set
62static inline uint32_t
63upos_abs_diff (uint32_t a, uint32_t b)
64{
65 long d1 = b - a;
66 long d2 = (d1 & (d1 >> 31)) << 1;
67
68 return d1 - d2; // == (b - d) - (a + d);
69}
70
71// Both a and b must not have the most significant bit set
72static inline uint32_t
73upos_min (uint32_t a, uint32_t b)
74{
75 int32_t d = b - a;
76 d &= d >> 31;
77 return a + d;
78}
79
80// Both a and b must not have the most significant bit set
81static inline uint32_t
82upos_max (uint32_t a, uint32_t b)
83{
84 int32_t d = b - a;
85 d &= d >> 31;
86 return b - d;
87}
88
89// this is much faster than crossfires original algorithm
90// on modern cpus
91inline int
92isqrt (int n)
93{
94 return (int)sqrtf ((float)n);
95}
96
97// this is only twice as fast as naive sqrtf (dx*dy+dy*dy)
98#if 0
99// and has a max. error of 6 in the range -100..+100.
100#else
101// and has a max. error of 9 in the range -100..+100.
102#endif
103inline int
104idistance (int dx, int dy)
105{
106 unsigned int dx_ = abs (dx);
107 unsigned int dy_ = abs (dy);
108
109#if 0
110 return dx_ > dy_
111 ? (dx_ * 61685 + dy_ * 26870) >> 16
112 : (dy_ * 61685 + dx_ * 26870) >> 16;
113#else
114 return dx_ + dy_ - min (dx_, dy_) * 5 / 8;
115#endif
116}
117
118/*
119 * absdir(int): Returns a number between 1 and 8, which represent
120 * the "absolute" direction of a number (it actually takes care of
121 * "overflow" in previous calculations of a direction).
122 */
123inline int
124absdir (int d)
125{
126 return ((d - 1) & 7) + 1;
127}
128
29// makes dynamically allocated objects zero-initialised 129// makes dynamically allocated objects zero-initialised
30struct zero_initialised 130struct zero_initialised
31{ 131{
32 void *operator new (size_t s, void *p) 132 void *operator new (size_t s, void *p)
33 { 133 {
… …
74 174
75// for symmetry 175// for symmetry
76template<typename T> 176template<typename T>
77inline void sfree (T *ptr, int n = 1) throw () 177inline void sfree (T *ptr, int n = 1) throw ()
78{ 178{
179#ifdef PREFER_MALLOC
180 free (ptr);
181#else
79 g_slice_free1 (n * sizeof (T), (void *)ptr); 182 g_slice_free1 (n * sizeof (T), (void *)ptr);
183#endif
80} 184}
81 185
82// a STL-compatible allocator that uses g_slice 186// a STL-compatible allocator that uses g_slice
83// boy, this is verbose 187// boy, this is verbose
84template<typename Tp> 188template<typename Tp>
… …
131 void destroy (pointer p) 235 void destroy (pointer p)
132 { 236 {
133 p->~Tp (); 237 p->~Tp ();
134 } 238 }
135}; 239};
240
241// P. L'Ecuyer, “Maximally Equidistributed Combined Tausworthe Generators”, Mathematics of Computation, 65, 213 (1996), 203–213.
242// http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme.ps
243// http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme2.ps
244struct tausworthe_random_generator
245{
246 // generator
247 uint32_t state [4];
248
249 void operator =(const tausworthe_random_generator &src)
250 {
251 state [0] = src.state [0];
252 state [1] = src.state [1];
253 state [2] = src.state [2];
254 state [3] = src.state [3];
255 }
256
257 void seed (uint32_t seed);
258 uint32_t next ();
259
260 // uniform distribution
261 uint32_t operator ()(uint32_t r_max)
262 {
263 return is_constant (r_max)
264 ? this->next () % r_max
265 : get_range (r_max);
266 }
267
268 // return a number within (min .. max)
269 int operator () (int r_min, int r_max)
270 {
271 return is_constant (r_min) && is_constant (r_max)
272 ? r_min + (*this) (max (r_max - r_min + 1, 1))
273 : get_range (r_min, r_max);
274 }
275
276 double operator ()()
277 {
278 return this->next () / (double)0xFFFFFFFFU;
279 }
280
281protected:
282 uint32_t get_range (uint32_t r_max);
283 int get_range (int r_min, int r_max);
284};
285
286typedef tausworthe_random_generator rand_gen;
287
288extern rand_gen rndm;
136 289
137template<class T> 290template<class T>
138struct refptr 291struct refptr
139{ 292{
140 T *p; 293 T *p;
… …
258 { 411 {
259 errase (&obj); 412 errase (&obj);
260 } 413 }
261}; 414};
262 415
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 416// basically does what strncpy should do, but appends "..." to strings exceeding length
270void assign (char *dst, const char *src, int maxlen); 417void assign (char *dst, const char *src, int maxlen);
271 418
272// type-safe version of assign 419// type-safe version of assign
273template<int N> 420template<int N>

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