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"
29 #include "cpp11_container.h"
35 * This class permits to cache getFacePosition call results
36 * This reduces CPU usage and vector calls
38 class FacePositionCache
41 static std::vector<v3s16> getFacePositions(u16 d);
43 static void generateFacePosition(u16 d);
44 static UNORDERED_MAP<u16, std::vector<v3s16> > m_cache;
45 static Mutex m_cache_mutex;
48 inline s16 getContainerPos(s16 p, s16 d)
50 return (p>=0 ? p : p-d+1) / d;
53 inline v2s16 getContainerPos(v2s16 p, s16 d)
56 getContainerPos(p.X, d),
57 getContainerPos(p.Y, d)
61 inline v3s16 getContainerPos(v3s16 p, s16 d)
64 getContainerPos(p.X, d),
65 getContainerPos(p.Y, d),
66 getContainerPos(p.Z, d)
70 inline v2s16 getContainerPos(v2s16 p, v2s16 d)
73 getContainerPos(p.X, d.X),
74 getContainerPos(p.Y, d.Y)
78 inline v3s16 getContainerPos(v3s16 p, v3s16 d)
81 getContainerPos(p.X, d.X),
82 getContainerPos(p.Y, d.Y),
83 getContainerPos(p.Z, d.Z)
87 inline void getContainerPosWithOffset(s16 p, s16 d, s16 &container, s16 &offset)
89 container = (p >= 0 ? p : p - d + 1) / d;
93 inline void getContainerPosWithOffset(const v2s16 &p, s16 d, v2s16 &container, v2s16 &offset)
95 getContainerPosWithOffset(p.X, d, container.X, offset.X);
96 getContainerPosWithOffset(p.Y, d, container.Y, offset.Y);
99 inline void getContainerPosWithOffset(const v3s16 &p, s16 d, v3s16 &container, v3s16 &offset)
101 getContainerPosWithOffset(p.X, d, container.X, offset.X);
102 getContainerPosWithOffset(p.Y, d, container.Y, offset.Y);
103 getContainerPosWithOffset(p.Z, d, container.Z, offset.Z);
107 inline bool isInArea(v3s16 p, s16 d)
110 p.X >= 0 && p.X < d &&
111 p.Y >= 0 && p.Y < d &&
116 inline bool isInArea(v2s16 p, s16 d)
119 p.X >= 0 && p.X < d &&
124 inline bool isInArea(v3s16 p, v3s16 d)
127 p.X >= 0 && p.X < d.X &&
128 p.Y >= 0 && p.Y < d.Y &&
129 p.Z >= 0 && p.Z < d.Z
133 #define rangelim(d, min, max) ((d) < (min) ? (min) : ((d)>(max)?(max):(d)))
134 #define myfloor(x) ((x) > 0.0 ? (int)(x) : (int)(x) - 1)
136 // The naive swap performs better than the xor version
137 #define SWAP(t, x, y) do { \
143 inline void sortBoxVerticies(v3s16 &p1, v3s16 &p2) {
145 SWAP(s16, p1.X, p2.X);
147 SWAP(s16, p1.Y, p2.Y);
149 SWAP(s16, p1.Z, p2.Z);
152 inline v3s16 componentwise_min(const v3s16 &a, const v3s16 &b)
154 return v3s16(MYMIN(a.X, b.X), MYMIN(a.Y, b.Y), MYMIN(a.Z, b.Z));
157 inline v3s16 componentwise_max(const v3s16 &a, const v3s16 &b)
159 return v3s16(MYMAX(a.X, b.X), MYMAX(a.Y, b.Y), MYMAX(a.Z, b.Z));
163 /** Returns \p f wrapped to the range [-360, 360]
165 * See test.cpp for example cases.
167 * \note This is also used in cases where degrees wrapped to the range [0, 360]
168 * is innapropriate (e.g. pitch needs negative values)
170 * \internal functionally equivalent -- although precision may vary slightly --
171 * to fmodf((f), 360.0f) however empirical tests indicate that this approach is
174 inline float modulo360f(float f)
189 fraction = f - whole;
192 return sign * (whole + fraction);
196 /** Returns \p f wrapped to the range [0, 360]
198 inline float wrapDegrees_0_360(float f)
200 float value = modulo360f(f);
201 return value < 0 ? value + 360 : value;
205 /** Returns \p f wrapped to the range [-180, 180]
207 inline float wrapDegrees_180(float f)
209 float value = modulo360f(f + 180);
216 Pseudo-random (VC++ rand() sucks)
218 #define MYRAND_RANGE 0xffffffff
220 void mysrand(unsigned int seed);
221 void myrand_bytes(void *out, size_t len);
222 int myrand_range(int min, int max);
225 Miscellaneous functions
228 inline u32 get_bits(u32 x, u32 pos, u32 len)
230 u32 mask = (1 << len) - 1;
231 return (x >> pos) & mask;
234 inline void set_bits(u32 *x, u32 pos, u32 len, u32 val)
236 u32 mask = (1 << len) - 1;
237 *x &= ~(mask << pos);
238 *x |= (val & mask) << pos;
241 inline u32 calc_parity(u32 v)
247 return (0x6996 >> v) & 1;
250 u64 murmur_hash_64_ua(const void *key, int len, unsigned int seed);
252 bool isBlockInSight(v3s16 blockpos_b, v3f camera_pos, v3f camera_dir,
253 f32 camera_fov, f32 range, f32 *distance_ptr=NULL);
256 Returns nearest 32-bit integer for given floating point number.
257 <cmath> and <math.h> in VC++ don't provide round().
259 inline s32 myround(f32 f)
261 return (s32)(f < 0.f ? (f - 0.5f) : (f + 0.5f));
265 Returns integer position of node in given floating point position
267 inline v3s16 floatToInt(v3f p, f32 d)
270 (p.X + (p.X>0 ? d/2 : -d/2))/d,
271 (p.Y + (p.Y>0 ? d/2 : -d/2))/d,
272 (p.Z + (p.Z>0 ? d/2 : -d/2))/d);
277 Returns floating point position of node in given integer position
279 inline v3f intToFloat(v3s16 p, f32 d)
289 // Random helper. Usually d=BS
290 inline aabb3f getNodeBox(v3s16 p, float d)
293 (float)p.X * d - 0.5*d,
294 (float)p.Y * d - 0.5*d,
295 (float)p.Z * d - 0.5*d,
296 (float)p.X * d + 0.5*d,
297 (float)p.Y * d + 0.5*d,
298 (float)p.Z * d + 0.5*d
302 class IntervalLimiter
310 dtime: time from last call to this method
311 wanted_interval: interval wanted
313 true: action should be skipped
314 false: action should be done
316 bool step(float dtime, float wanted_interval)
318 m_accumulator += dtime;
319 if(m_accumulator < wanted_interval)
321 m_accumulator -= wanted_interval;
329 Splits a list into "pages". For example, the list [1,2,3,4,5] split
330 into two pages would be [1,2,3],[4,5]. This function computes the
331 minimum and maximum indices of a single page.
333 length: Length of the list that should be split
334 page: Page number, 1 <= page <= pagecount
335 pagecount: The number of pages, >= 1
336 minindex: Receives the minimum index (inclusive).
337 maxindex: Receives the maximum index (exclusive).
339 Ensures 0 <= minindex <= maxindex <= length.
341 inline void paging(u32 length, u32 page, u32 pagecount, u32 &minindex, u32 &maxindex)
343 if(length < 1 || pagecount < 1 || page < 1 || page > pagecount)
345 // Special cases or invalid parameters
346 minindex = maxindex = 0;
348 else if(pagecount <= length)
350 // Less pages than entries in the list:
351 // Each page contains at least one entry
352 minindex = (length * (page-1) + (pagecount-1)) / pagecount;
353 maxindex = (length * page + (pagecount-1)) / pagecount;
357 // More pages than entries in the list:
358 // Make sure the empty pages are at the end
372 inline float cycle_shift(float value, float by = 0, float max = 1)
374 if (value + by < 0) return max + by + value;
375 if (value + by > max) return value + by - max;
379 inline bool is_power_of_two(u32 n)
381 return n != 0 && (n & (n-1)) == 0;
384 // Compute next-higher power of 2 efficiently, e.g. for power-of-2 texture sizes.
385 // Public Domain: https://graphics.stanford.edu/~seander/bithacks.html#RoundUpPowerOf2
386 inline u32 npot2(u32 orig) {