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.
22 #include "basic_macros.h"
23 #include "irrlichttypes.h"
26 #include "irr_aabb3d.h"
28 #define rangelim(d, min, max) ((d) < (min) ? (min) : ((d) > (max) ? (max) : (d)))
29 #define myfloor(x) ((x) < 0.0 ? (int)(x) - 1 : (int)(x))
30 // The naive swap performs better than the xor version
31 #define SWAP(t, x, y) do { \
38 inline s16 getContainerPos(s16 p, s16 d)
40 return (p >= 0 ? p : p - d + 1) / d;
43 inline v2s16 getContainerPos(v2s16 p, s16 d)
46 getContainerPos(p.X, d),
47 getContainerPos(p.Y, d)
51 inline v3s16 getContainerPos(v3s16 p, s16 d)
54 getContainerPos(p.X, d),
55 getContainerPos(p.Y, d),
56 getContainerPos(p.Z, d)
60 inline v2s16 getContainerPos(v2s16 p, v2s16 d)
63 getContainerPos(p.X, d.X),
64 getContainerPos(p.Y, d.Y)
68 inline v3s16 getContainerPos(v3s16 p, v3s16 d)
71 getContainerPos(p.X, d.X),
72 getContainerPos(p.Y, d.Y),
73 getContainerPos(p.Z, d.Z)
77 inline void getContainerPosWithOffset(s16 p, s16 d, s16 &container, s16 &offset)
79 container = (p >= 0 ? p : p - d + 1) / d;
83 inline void getContainerPosWithOffset(const v2s16 &p, s16 d, v2s16 &container, v2s16 &offset)
85 getContainerPosWithOffset(p.X, d, container.X, offset.X);
86 getContainerPosWithOffset(p.Y, d, container.Y, offset.Y);
89 inline void getContainerPosWithOffset(const v3s16 &p, s16 d, v3s16 &container, v3s16 &offset)
91 getContainerPosWithOffset(p.X, d, container.X, offset.X);
92 getContainerPosWithOffset(p.Y, d, container.Y, offset.Y);
93 getContainerPosWithOffset(p.Z, d, container.Z, offset.Z);
97 inline bool isInArea(v3s16 p, s16 d)
100 p.X >= 0 && p.X < d &&
101 p.Y >= 0 && p.Y < d &&
106 inline bool isInArea(v2s16 p, s16 d)
109 p.X >= 0 && p.X < d &&
114 inline bool isInArea(v3s16 p, v3s16 d)
117 p.X >= 0 && p.X < d.X &&
118 p.Y >= 0 && p.Y < d.Y &&
119 p.Z >= 0 && p.Z < d.Z
123 inline void sortBoxVerticies(v3s16 &p1, v3s16 &p2) {
125 SWAP(s16, p1.X, p2.X);
127 SWAP(s16, p1.Y, p2.Y);
129 SWAP(s16, p1.Z, p2.Z);
132 inline v3s16 componentwise_min(const v3s16 &a, const v3s16 &b)
134 return v3s16(MYMIN(a.X, b.X), MYMIN(a.Y, b.Y), MYMIN(a.Z, b.Z));
137 inline v3s16 componentwise_max(const v3s16 &a, const v3s16 &b)
139 return v3s16(MYMAX(a.X, b.X), MYMAX(a.Y, b.Y), MYMAX(a.Z, b.Z));
143 /** Returns \p f wrapped to the range [-360, 360]
145 * See test.cpp for example cases.
147 * \note This is also used in cases where degrees wrapped to the range [0, 360]
148 * is innapropriate (e.g. pitch needs negative values)
150 * \internal functionally equivalent -- although precision may vary slightly --
151 * to fmodf((f), 360.0f) however empirical tests indicate that this approach is
154 inline float modulo360f(float f)
169 fraction = f - whole;
172 return sign * (whole + fraction);
176 /** Returns \p f wrapped to the range [0, 360]
178 inline float wrapDegrees_0_360(float f)
180 float value = modulo360f(f);
181 return value < 0 ? value + 360 : value;
185 /** Returns \p v3f wrapped to the range [0, 360]
187 inline v3f wrapDegrees_0_360_v3f(v3f v)
190 value_v3f.X = modulo360f(v.X);
191 value_v3f.Y = modulo360f(v.Y);
192 value_v3f.Z = modulo360f(v.Z);
194 // Now that values are wrapped, use to get values for certain ranges
195 value_v3f.X = value_v3f.X < 0 ? value_v3f.X + 360 : value_v3f.X;
196 value_v3f.Y = value_v3f.Y < 0 ? value_v3f.Y + 360 : value_v3f.Y;
197 value_v3f.Z = value_v3f.Z < 0 ? value_v3f.Z + 360 : value_v3f.Z;
202 /** Returns \p f wrapped to the range [-180, 180]
204 inline float wrapDegrees_180(float f)
206 float value = modulo360f(f + 180);
213 Pseudo-random (VC++ rand() sucks)
215 #define MYRAND_RANGE 0xffffffff
217 void mysrand(unsigned int seed);
218 void myrand_bytes(void *out, size_t len);
219 int myrand_range(int min, int max);
222 Miscellaneous functions
225 inline u32 get_bits(u32 x, u32 pos, u32 len)
227 u32 mask = (1 << len) - 1;
228 return (x >> pos) & mask;
231 inline void set_bits(u32 *x, u32 pos, u32 len, u32 val)
233 u32 mask = (1 << len) - 1;
234 *x &= ~(mask << pos);
235 *x |= (val & mask) << pos;
238 inline u32 calc_parity(u32 v)
244 return (0x6996 >> v) & 1;
247 u64 murmur_hash_64_ua(const void *key, int len, unsigned int seed);
249 bool isBlockInSight(v3s16 blockpos_b, v3f camera_pos, v3f camera_dir,
250 f32 camera_fov, f32 range, f32 *distance_ptr=NULL);
252 s16 adjustDist(s16 dist, float zoom_fov);
255 Returns nearest 32-bit integer for given floating point number.
256 <cmath> and <math.h> in VC++ don't provide round().
258 inline s32 myround(f32 f)
260 return (s32)(f < 0.f ? (f - 0.5f) : (f + 0.5f));
263 inline constexpr f32 sqr(f32 f)
269 Returns integer position of node in given floating point position
271 inline v3s16 floatToInt(v3f p, f32 d)
274 (p.X + (p.X > 0 ? d / 2 : -d / 2)) / d,
275 (p.Y + (p.Y > 0 ? d / 2 : -d / 2)) / d,
276 (p.Z + (p.Z > 0 ? d / 2 : -d / 2)) / d);
280 Returns integer position of node in given double precision position
282 inline v3s16 doubleToInt(v3d p, double d)
285 (p.X + (p.X > 0 ? d / 2 : -d / 2)) / d,
286 (p.Y + (p.Y > 0 ? d / 2 : -d / 2)) / d,
287 (p.Z + (p.Z > 0 ? d / 2 : -d / 2)) / d);
291 Returns floating point position of node in given integer position
293 inline v3f intToFloat(v3s16 p, f32 d)
302 // Random helper. Usually d=BS
303 inline aabb3f getNodeBox(v3s16 p, float d)
306 (float)p.X * d - 0.5f * d,
307 (float)p.Y * d - 0.5f * d,
308 (float)p.Z * d - 0.5f * d,
309 (float)p.X * d + 0.5f * d,
310 (float)p.Y * d + 0.5f * d,
311 (float)p.Z * d + 0.5f * d
316 class IntervalLimiter
319 IntervalLimiter() = default;
322 dtime: time from last call to this method
323 wanted_interval: interval wanted
325 true: action should be skipped
326 false: action should be done
328 bool step(float dtime, float wanted_interval)
330 m_accumulator += dtime;
331 if (m_accumulator < wanted_interval)
333 m_accumulator -= wanted_interval;
338 float m_accumulator = 0.0f;
343 Splits a list into "pages". For example, the list [1,2,3,4,5] split
344 into two pages would be [1,2,3],[4,5]. This function computes the
345 minimum and maximum indices of a single page.
347 length: Length of the list that should be split
348 page: Page number, 1 <= page <= pagecount
349 pagecount: The number of pages, >= 1
350 minindex: Receives the minimum index (inclusive).
351 maxindex: Receives the maximum index (exclusive).
353 Ensures 0 <= minindex <= maxindex <= length.
355 inline void paging(u32 length, u32 page, u32 pagecount, u32 &minindex, u32 &maxindex)
357 if (length < 1 || pagecount < 1 || page < 1 || page > pagecount) {
358 // Special cases or invalid parameters
359 minindex = maxindex = 0;
360 } else if(pagecount <= length) {
361 // Less pages than entries in the list:
362 // Each page contains at least one entry
363 minindex = (length * (page-1) + (pagecount-1)) / pagecount;
364 maxindex = (length * page + (pagecount-1)) / pagecount;
366 // More pages than entries in the list:
367 // Make sure the empty pages are at the end
378 inline float cycle_shift(float value, float by = 0, float max = 1)
380 if (value + by < 0) return value + by + max;
381 if (value + by > max) return value + by - max;
385 inline bool is_power_of_two(u32 n)
387 return n != 0 && (n & (n - 1)) == 0;
390 // Compute next-higher power of 2 efficiently, e.g. for power-of-2 texture sizes.
391 // Public Domain: https://graphics.stanford.edu/~seander/bithacks.html#RoundUpPowerOf2
392 inline u32 npot2(u32 orig) {
402 // Gradual steps towards the target value in a wrapped (circular) system
403 // using the shorter of both ways
405 inline void wrappedApproachShortest(T ¤t, const T target, const T stepsize,
408 T delta = target - current;
412 if (delta > stepsize && maximum - delta > stepsize) {
413 current += (delta < maximum / 2) ? stepsize : -stepsize;
414 if (current >= maximum)