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"
29 #define rangelim(d, min, max) ((d) < (min) ? (min) : ((d) > (max) ? (max) : (d)))
30 #define myfloor(x) ((x) < 0.0 ? (int)(x) - 1 : (int)(x))
31 // The naive swap performs better than the xor version
32 #define SWAP(t, x, y) do { \
39 inline s16 getContainerPos(s16 p, s16 d)
41 return (p >= 0 ? p : p - d + 1) / d;
44 inline v2s16 getContainerPos(v2s16 p, s16 d)
47 getContainerPos(p.X, d),
48 getContainerPos(p.Y, d)
52 inline v3s16 getContainerPos(v3s16 p, s16 d)
55 getContainerPos(p.X, d),
56 getContainerPos(p.Y, d),
57 getContainerPos(p.Z, d)
61 inline v2s16 getContainerPos(v2s16 p, v2s16 d)
64 getContainerPos(p.X, d.X),
65 getContainerPos(p.Y, d.Y)
69 inline v3s16 getContainerPos(v3s16 p, v3s16 d)
72 getContainerPos(p.X, d.X),
73 getContainerPos(p.Y, d.Y),
74 getContainerPos(p.Z, d.Z)
78 inline void getContainerPosWithOffset(s16 p, s16 d, s16 &container, s16 &offset)
80 container = (p >= 0 ? p : p - d + 1) / d;
84 inline void getContainerPosWithOffset(const v2s16 &p, s16 d, v2s16 &container, v2s16 &offset)
86 getContainerPosWithOffset(p.X, d, container.X, offset.X);
87 getContainerPosWithOffset(p.Y, d, container.Y, offset.Y);
90 inline void getContainerPosWithOffset(const v3s16 &p, s16 d, v3s16 &container, v3s16 &offset)
92 getContainerPosWithOffset(p.X, d, container.X, offset.X);
93 getContainerPosWithOffset(p.Y, d, container.Y, offset.Y);
94 getContainerPosWithOffset(p.Z, d, container.Z, offset.Z);
98 inline bool isInArea(v3s16 p, s16 d)
101 p.X >= 0 && p.X < d &&
102 p.Y >= 0 && p.Y < d &&
107 inline bool isInArea(v2s16 p, s16 d)
110 p.X >= 0 && p.X < d &&
115 inline bool isInArea(v3s16 p, v3s16 d)
118 p.X >= 0 && p.X < d.X &&
119 p.Y >= 0 && p.Y < d.Y &&
120 p.Z >= 0 && p.Z < d.Z
124 inline void sortBoxVerticies(v3s16 &p1, v3s16 &p2) {
126 SWAP(s16, p1.X, p2.X);
128 SWAP(s16, p1.Y, p2.Y);
130 SWAP(s16, p1.Z, p2.Z);
133 inline v3s16 componentwise_min(const v3s16 &a, const v3s16 &b)
135 return v3s16(MYMIN(a.X, b.X), MYMIN(a.Y, b.Y), MYMIN(a.Z, b.Z));
138 inline v3s16 componentwise_max(const v3s16 &a, const v3s16 &b)
140 return v3s16(MYMAX(a.X, b.X), MYMAX(a.Y, b.Y), MYMAX(a.Z, b.Z));
144 /** Returns \p f wrapped to the range [-360, 360]
146 * See test.cpp for example cases.
148 * \note This is also used in cases where degrees wrapped to the range [0, 360]
149 * is innapropriate (e.g. pitch needs negative values)
151 * \internal functionally equivalent -- although precision may vary slightly --
152 * to fmodf((f), 360.0f) however empirical tests indicate that this approach is
155 inline float modulo360f(float f)
170 fraction = f - whole;
173 return sign * (whole + fraction);
177 /** Returns \p f wrapped to the range [0, 360]
179 inline float wrapDegrees_0_360(float f)
181 float value = modulo360f(f);
182 return value < 0 ? value + 360 : value;
186 /** Returns \p f wrapped to the range [-180, 180]
188 inline float wrapDegrees_180(float f)
190 float value = modulo360f(f + 180);
197 Pseudo-random (VC++ rand() sucks)
199 #define MYRAND_RANGE 0xffffffff
201 void mysrand(unsigned int seed);
202 void myrand_bytes(void *out, size_t len);
203 int myrand_range(int min, int max);
206 Miscellaneous functions
209 inline u32 get_bits(u32 x, u32 pos, u32 len)
211 u32 mask = (1 << len) - 1;
212 return (x >> pos) & mask;
215 inline void set_bits(u32 *x, u32 pos, u32 len, u32 val)
217 u32 mask = (1 << len) - 1;
218 *x &= ~(mask << pos);
219 *x |= (val & mask) << pos;
222 inline u32 calc_parity(u32 v)
228 return (0x6996 >> v) & 1;
231 u64 murmur_hash_64_ua(const void *key, int len, unsigned int seed);
233 bool isBlockInSight(v3s16 blockpos_b, v3f camera_pos, v3f camera_dir,
234 f32 camera_fov, f32 range, f32 *distance_ptr=NULL);
237 Returns nearest 32-bit integer for given floating point number.
238 <cmath> and <math.h> in VC++ don't provide round().
240 inline s32 myround(f32 f)
242 return (s32)(f < 0.f ? (f - 0.5f) : (f + 0.5f));
246 Returns integer position of node in given floating point position
248 inline v3s16 floatToInt(v3f p, f32 d)
251 (p.X + (p.X > 0 ? d / 2 : -d / 2)) / d,
252 (p.Y + (p.Y > 0 ? d / 2 : -d / 2)) / d,
253 (p.Z + (p.Z > 0 ? d / 2 : -d / 2)) / d);
257 Returns floating point position of node in given integer position
259 inline v3f intToFloat(v3s16 p, f32 d)
268 // Random helper. Usually d=BS
269 inline aabb3f getNodeBox(v3s16 p, float d)
272 (float)p.X * d - 0.5 * d,
273 (float)p.Y * d - 0.5 * d,
274 (float)p.Z * d - 0.5 * d,
275 (float)p.X * d + 0.5 * d,
276 (float)p.Y * d + 0.5 * d,
277 (float)p.Z * d + 0.5 * d
282 class IntervalLimiter
287 dtime: time from last call to this method
288 wanted_interval: interval wanted
290 true: action should be skipped
291 false: action should be done
293 bool step(float dtime, float wanted_interval)
295 m_accumulator += dtime;
296 if (m_accumulator < wanted_interval)
298 m_accumulator -= wanted_interval;
303 float m_accumulator = 0.0f;
308 Splits a list into "pages". For example, the list [1,2,3,4,5] split
309 into two pages would be [1,2,3],[4,5]. This function computes the
310 minimum and maximum indices of a single page.
312 length: Length of the list that should be split
313 page: Page number, 1 <= page <= pagecount
314 pagecount: The number of pages, >= 1
315 minindex: Receives the minimum index (inclusive).
316 maxindex: Receives the maximum index (exclusive).
318 Ensures 0 <= minindex <= maxindex <= length.
320 inline void paging(u32 length, u32 page, u32 pagecount, u32 &minindex, u32 &maxindex)
322 if (length < 1 || pagecount < 1 || page < 1 || page > pagecount) {
323 // Special cases or invalid parameters
324 minindex = maxindex = 0;
325 } else if(pagecount <= length) {
326 // Less pages than entries in the list:
327 // Each page contains at least one entry
328 minindex = (length * (page-1) + (pagecount-1)) / pagecount;
329 maxindex = (length * page + (pagecount-1)) / pagecount;
331 // More pages than entries in the list:
332 // Make sure the empty pages are at the end
343 inline float cycle_shift(float value, float by = 0, float max = 1)
345 if (value + by < 0) return value + by + max;
346 if (value + by > max) return value + by - max;
350 inline bool is_power_of_two(u32 n)
352 return n != 0 && (n & (n - 1)) == 0;
355 // Compute next-higher power of 2 efficiently, e.g. for power-of-2 texture sizes.
356 // Public Domain: https://graphics.stanford.edu/~seander/bithacks.html#RoundUpPowerOf2
357 inline u32 npot2(u32 orig) {