3 Copyright (C) 2010-2013 celeron55, Perttu Ahola <celeron55@gmail.com>
5 This program is free software; you can redistribute it and/or modify
6 it under the terms of the GNU Lesser General Public License as published by
7 the Free Software Foundation; either version 2.1 of the License, or
8 (at your option) any later version.
10 This program is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 GNU Lesser General Public License for more details.
15 You should have received a copy of the GNU Lesser General Public License along
16 with this program; if not, write to the Free Software Foundation, Inc.,
17 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
20 #ifndef UTIL_NUMERIC_HEADER
21 #define UTIL_NUMERIC_HEADER
23 #include "basic_macros.h"
24 #include "../irrlichttypes.h"
25 #include "../irr_v2d.h"
26 #include "../irr_v3d.h"
27 #include "../irr_aabb3d.h"
28 #include "../threading/mutex.h"
30 #define rangelim(d, min, max) ((d) < (min) ? (min) : ((d) > (max) ? (max) : (d)))
31 #define myfloor(x) ((x) < 0.0 ? (int)(x) - 1 : (int)(x))
32 // The naive swap performs better than the xor version
33 #define SWAP(t, x, y) do { \
40 inline s16 getContainerPos(s16 p, s16 d)
42 return (p >= 0 ? p : p - d + 1) / d;
45 inline v2s16 getContainerPos(v2s16 p, s16 d)
48 getContainerPos(p.X, d),
49 getContainerPos(p.Y, d)
53 inline v3s16 getContainerPos(v3s16 p, s16 d)
56 getContainerPos(p.X, d),
57 getContainerPos(p.Y, d),
58 getContainerPos(p.Z, d)
62 inline v2s16 getContainerPos(v2s16 p, v2s16 d)
65 getContainerPos(p.X, d.X),
66 getContainerPos(p.Y, d.Y)
70 inline v3s16 getContainerPos(v3s16 p, v3s16 d)
73 getContainerPos(p.X, d.X),
74 getContainerPos(p.Y, d.Y),
75 getContainerPos(p.Z, d.Z)
79 inline void getContainerPosWithOffset(s16 p, s16 d, s16 &container, s16 &offset)
81 container = (p >= 0 ? p : p - d + 1) / d;
85 inline void getContainerPosWithOffset(const v2s16 &p, s16 d, v2s16 &container, v2s16 &offset)
87 getContainerPosWithOffset(p.X, d, container.X, offset.X);
88 getContainerPosWithOffset(p.Y, d, container.Y, offset.Y);
91 inline void getContainerPosWithOffset(const v3s16 &p, s16 d, v3s16 &container, v3s16 &offset)
93 getContainerPosWithOffset(p.X, d, container.X, offset.X);
94 getContainerPosWithOffset(p.Y, d, container.Y, offset.Y);
95 getContainerPosWithOffset(p.Z, d, container.Z, offset.Z);
99 inline bool isInArea(v3s16 p, s16 d)
102 p.X >= 0 && p.X < d &&
103 p.Y >= 0 && p.Y < d &&
108 inline bool isInArea(v2s16 p, s16 d)
111 p.X >= 0 && p.X < d &&
116 inline bool isInArea(v3s16 p, v3s16 d)
119 p.X >= 0 && p.X < d.X &&
120 p.Y >= 0 && p.Y < d.Y &&
121 p.Z >= 0 && p.Z < d.Z
125 inline void sortBoxVerticies(v3s16 &p1, v3s16 &p2) {
127 SWAP(s16, p1.X, p2.X);
129 SWAP(s16, p1.Y, p2.Y);
131 SWAP(s16, p1.Z, p2.Z);
134 inline v3s16 componentwise_min(const v3s16 &a, const v3s16 &b)
136 return v3s16(MYMIN(a.X, b.X), MYMIN(a.Y, b.Y), MYMIN(a.Z, b.Z));
139 inline v3s16 componentwise_max(const v3s16 &a, const v3s16 &b)
141 return v3s16(MYMAX(a.X, b.X), MYMAX(a.Y, b.Y), MYMAX(a.Z, b.Z));
145 /** Returns \p f wrapped to the range [-360, 360]
147 * See test.cpp for example cases.
149 * \note This is also used in cases where degrees wrapped to the range [0, 360]
150 * is innapropriate (e.g. pitch needs negative values)
152 * \internal functionally equivalent -- although precision may vary slightly --
153 * to fmodf((f), 360.0f) however empirical tests indicate that this approach is
156 inline float modulo360f(float f)
171 fraction = f - whole;
174 return sign * (whole + fraction);
178 /** Returns \p f wrapped to the range [0, 360]
180 inline float wrapDegrees_0_360(float f)
182 float value = modulo360f(f);
183 return value < 0 ? value + 360 : value;
187 /** Returns \p f wrapped to the range [-180, 180]
189 inline float wrapDegrees_180(float f)
191 float value = modulo360f(f + 180);
198 Pseudo-random (VC++ rand() sucks)
200 #define MYRAND_RANGE 0xffffffff
202 void mysrand(unsigned int seed);
203 void myrand_bytes(void *out, size_t len);
204 int myrand_range(int min, int max);
207 Miscellaneous functions
210 inline u32 get_bits(u32 x, u32 pos, u32 len)
212 u32 mask = (1 << len) - 1;
213 return (x >> pos) & mask;
216 inline void set_bits(u32 *x, u32 pos, u32 len, u32 val)
218 u32 mask = (1 << len) - 1;
219 *x &= ~(mask << pos);
220 *x |= (val & mask) << pos;
223 inline u32 calc_parity(u32 v)
229 return (0x6996 >> v) & 1;
232 u64 murmur_hash_64_ua(const void *key, int len, unsigned int seed);
234 bool isBlockInSight(v3s16 blockpos_b, v3f camera_pos, v3f camera_dir,
235 f32 camera_fov, f32 range, f32 *distance_ptr=NULL);
238 Returns nearest 32-bit integer for given floating point number.
239 <cmath> and <math.h> in VC++ don't provide round().
241 inline s32 myround(f32 f)
243 return (s32)(f < 0.f ? (f - 0.5f) : (f + 0.5f));
247 Returns integer position of node in given floating point position
249 inline v3s16 floatToInt(v3f p, f32 d)
252 (p.X + (p.X > 0 ? d / 2 : -d / 2)) / d,
253 (p.Y + (p.Y > 0 ? d / 2 : -d / 2)) / d,
254 (p.Z + (p.Z > 0 ? d / 2 : -d / 2)) / d);
258 Returns floating point position of node in given integer position
260 inline v3f intToFloat(v3s16 p, f32 d)
269 // Random helper. Usually d=BS
270 inline aabb3f getNodeBox(v3s16 p, float d)
273 (float)p.X * d - 0.5 * d,
274 (float)p.Y * d - 0.5 * d,
275 (float)p.Z * d - 0.5 * d,
276 (float)p.X * d + 0.5 * d,
277 (float)p.Y * d + 0.5 * d,
278 (float)p.Z * d + 0.5 * d
283 class IntervalLimiter
286 IntervalLimiter() : m_accumulator(0) {}
288 dtime: time from last call to this method
289 wanted_interval: interval wanted
291 true: action should be skipped
292 false: action should be done
294 bool step(float dtime, float wanted_interval)
296 m_accumulator += dtime;
297 if (m_accumulator < wanted_interval)
299 m_accumulator -= wanted_interval;
309 Splits a list into "pages". For example, the list [1,2,3,4,5] split
310 into two pages would be [1,2,3],[4,5]. This function computes the
311 minimum and maximum indices of a single page.
313 length: Length of the list that should be split
314 page: Page number, 1 <= page <= pagecount
315 pagecount: The number of pages, >= 1
316 minindex: Receives the minimum index (inclusive).
317 maxindex: Receives the maximum index (exclusive).
319 Ensures 0 <= minindex <= maxindex <= length.
321 inline void paging(u32 length, u32 page, u32 pagecount, u32 &minindex, u32 &maxindex)
323 if (length < 1 || pagecount < 1 || page < 1 || page > pagecount) {
324 // Special cases or invalid parameters
325 minindex = maxindex = 0;
326 } else if(pagecount <= length) {
327 // Less pages than entries in the list:
328 // Each page contains at least one entry
329 minindex = (length * (page-1) + (pagecount-1)) / pagecount;
330 maxindex = (length * page + (pagecount-1)) / pagecount;
332 // More pages than entries in the list:
333 // Make sure the empty pages are at the end
344 inline float cycle_shift(float value, float by = 0, float max = 1)
346 if (value + by < 0) return value + by + max;
347 if (value + by > max) return value + by - max;
351 inline bool is_power_of_two(u32 n)
353 return n != 0 && (n & (n - 1)) == 0;
356 // Compute next-higher power of 2 efficiently, e.g. for power-of-2 texture sizes.
357 // Public Domain: https://graphics.stanford.edu/~seander/bithacks.html#RoundUpPowerOf2
358 inline u32 npot2(u32 orig) {