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/cvs/deliantra/server/include/noise.h
Revision: 1.22
Committed: Sat Nov 17 23:40:01 2018 UTC (5 years, 5 months ago) by root
Content type: text/plain
Branch: MAIN
CVS Tags: HEAD
Changes since 1.21: +1 -0 lines
Log Message:
copyright update 2018

File Contents

# Content
1 /*
2 * This file is part of Deliantra, the Roguelike Realtime MMORPG.
3 *
4 * Copyright (©) 2017,2018 Marc Alexander Lehmann / the Deliantra team
5 * Copyright (©) 2010,2011,2012,2013,2014,2015,2016 Marc Alexander Lehmann / Robin Redeker / the Deliantra team
6 *
7 * Deliantra is free software: you can redistribute it and/or modify it under
8 * the terms of the Affero GNU General Public License as published by the
9 * Free Software Foundation, either version 3 of the License, or (at your
10 * option) any later version.
11 *
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
16 *
17 * You should have received a copy of the Affero GNU General Public License
18 * and the GNU General Public License along with this program. If not, see
19 * <http://www.gnu.org/licenses/>.
20 *
21 * The authors can be reached via e-mail to <support@deliantra.net>
22 */
23
24 #ifndef NOISE_H_
25 #define NOISE_H_
26
27 #if 0 // blitz++0.09
28 #include <string.h> // workaround for tinyvec using memcpy without including string.h
29 #include <cstdlib> // workaround for tinyvec using labs without including cstdlib
30 #include <blitz/tinyvec.h>
31 #include <blitz/tinyvec-et.h>
32 typedef blitz::TinyVector<float,2> vec2d;
33 typedef blitz::TinyVector<float,3> vec3d;
34 #else
35
36 // blitz++ 0.10 - not working
37 #include <blitz/array.h>
38 #include <blitz/tinyvec2.h>
39 #include <blitz/tinyvec2.cc>
40
41 template<typename T, int length>
42 struct vecnd
43 : blitz::TinyVector<T, length>
44 {
45 static const int numElements = length;
46 using blitz::TinyVector<T, length>::TinyVector;
47 };
48
49 typedef vecnd<float,2> vec2d;
50 typedef vecnd<float,3> vec3d;
51
52 #endif
53
54 #include "global.h"
55
56 vec2d
57 inline floor (vec2d v)
58 {
59 return vec2d (fastfloor (v[0]), fastfloor (v[1]));
60 }
61
62 vec3d
63 inline floor (vec3d v)
64 {
65 return vec3d (fastfloor (v[0]), fastfloor (v[1]), fastfloor (v[2]));
66 }
67
68 vec2d
69 inline pow (vec2d v, vec2d p)
70 {
71 return vec2d (pow (v[0], p[0]), pow (v[1], p[1]));
72 }
73
74 /////////////////////////////////////////////////////////////////////////////
75
76 // various s-shaped curves, smooth to, first, or second derivative
77 // used for smooth interpolation from 0..1
78
79 // linear
80 template<typename T>
81 inline T
82 sigmoid0 (T x)
83 {
84 return x;
85 }
86
87 // 3x²-2x³
88 template<typename T>
89 inline T
90 sigmoid1 (T x)
91 {
92 return (3 - 2 * x) * x * x;
93 }
94
95 // 6x⁵ - 15x⁴ + 10x³
96 template<typename T>
97 inline T
98 sigmoid2 (T x)
99 {
100 #ifdef MORE_PARALLELITY
101 float x2 = x * x;
102 float x4 = x2 * x2;
103
104 return (6 * x4 + 10 * x2) * x - 15 * x4;
105 #endif
106
107 // simple horner
108 return ((6 * x - 15) * x + 10) * x * x * x;
109 }
110
111 // blend between a and b
112 // c is the control function - if lower than ca
113 // then return a, if higher than cb, return b
114 template<typename T, typename U>
115 inline T
116 blend (T a, T b, U c, U ca, U cb, U weight (U) = sigmoid1)
117 {
118 if (c <= ca) return a;
119 if (c >= cb) return b;
120
121 U w = weight ((c - ca) / (cb - ca));
122 return (U(1) - w) * a + w * b;
123 }
124
125 // blend between a and b
126 // c is the control function - if lower than -c_w
127 // then return a, if higher than +c_w then b.
128 template<typename T, typename U>
129 inline T
130 blend0 (T a, T b, U c, U c_w, U weight (U) = sigmoid1)
131 {
132 return blend<T,U> (a, b, c, -c_w, c_w, weight);
133 }
134
135 template<class vec_t, int a, int b>
136 struct rotate_nn
137 {
138 typename vec_t::T_numtype s, c;
139
140 void set (typename vec_t::T_numtype angle)
141 {
142 s = sin (angle);
143 c = cos (angle);
144 }
145
146 void operator ()(vec_t &P) const
147 {
148 vec_t o = P;
149
150 P[a] = o[a] * c - o[b] * s;
151 P[b] = o[a] * s + o[b] * c;
152 }
153 };
154
155 template<class vec_t>
156 struct rotate_xy : rotate_nn<vec_t, 0, 1>
157 {
158 };
159
160 template<class vec_t>
161 struct rotate_xz : rotate_nn<vec_t, 0, 2>
162 {
163 };
164
165 template<class vec_t>
166 struct rotate_yz : rotate_nn<vec_t, 1, 2>
167 {
168 };
169
170 /////////////////////////////////////////////////////////////////////////////
171
172 template< int N, typename T>
173 struct permutation
174 {
175 T pmap[N];
176
177 void seed (seedable_rand_gen &rng);
178
179 ecb_pure T operator ()(T v)
180 {
181 return pmap[v & T(N - 1)];
182 }
183 };
184
185 /////////////////////////////////////////////////////////////////////////////
186
187 template<class vec_t>
188 struct noise_gen_base
189 {
190 permutation<256, uint8_t> rvmap[vec_t::numElements + 1];
191
192 typedef typename vec_t::T_numtype value_t;
193
194 void seed (seedable_rand_gen &rng);
195 void seed (seed_t seed);
196
197 ecb_pure value_t operator ()(vec_t P, uint32_t seed = 0);
198 };
199
200 template<class vec_t>
201 struct noise_gen;
202
203 // modelled after 2d/3d kensler noise without projection
204 template<>
205 struct noise_gen<vec2d>
206 : noise_gen_base<vec2d>
207 {
208 static value_t abs_avg() { return 0.2231; } // avg(abs(noise))
209 };
210
211 template<>
212 struct noise_gen<vec3d>
213 : noise_gen_base<vec3d>
214 {
215 static vec3d::T_numtype abs_avg() { return 0.415; } // avg(abs(noise))
216
217 using noise_gen_base<vec3d>::operator ();
218
219 // noise projected on a surface with normal n
220 ecb_pure vec2d::T_numtype operator() (vec3d P, vec3d N, uint32_t seed = 0);
221 };
222
223 typedef noise_gen<vec2d> noise2d;
224 typedef noise_gen<vec3d> noise3d;
225
226 /////////////////////////////////////////////////////////////////////////////
227
228 template<class vec_t>
229 struct frac_gen
230 : noise_gen<vec_t>
231 {
232 enum { MAX_OCTAVES = 32 };
233
234 typedef typename vec_t::T_numtype value_t;
235
236 int octaves;
237 value_t h, lac, ex[MAX_OCTAVES];
238 value_t fbm_mul[MAX_OCTAVES];
239 rotate_xy<vec_t> rot[MAX_OCTAVES];
240
241 frac_gen (int octaves = 3, value_t lacunarity = 2, value_t hurst_expo = .5, uint32_t seed = 0);
242
243 ecb_pure value_t noise (vec_t P, uint32_t seed = 0)
244 {
245 return this->operator() (P, seed);
246 }
247
248 ecb_pure value_t fBm (vec_t P);
249 ecb_pure value_t turbulence (vec_t P);
250 ecb_pure value_t multifractal (vec_t P, value_t offset = 1);
251 ecb_pure value_t heterofractal (vec_t P, value_t offset = 1);
252 ecb_pure value_t hybridfractal (vec_t P, value_t offset = 1, value_t gain = 1);
253 ecb_pure value_t ridgedmultifractal (vec_t P, value_t offset = 1, value_t gain = 8);
254 ecb_pure value_t billowfractal (vec_t P, value_t offset = 1, value_t gain = 2);
255 ecb_pure value_t terrain (vec_t P);
256 ecb_pure value_t terrain2 (vec_t P);
257 };
258
259 typedef frac_gen<vec2d> frac2d;
260 typedef frac_gen<vec3d> frac3d;
261
262 /////////////////////////////////////////////////////////////////////////////
263
264 template<typename T, typename U>
265 inline T
266 border_blend (T a, T b, vec2d P, U N, U W)
267 {
268 U border = W; // within n places of the border
269
270 min_it (border, P [0]);
271 min_it (border, N - P [0]);
272 min_it (border, P [1]);
273 min_it (border, N - P [1]);
274
275 return blend (a, b, border, U(0), W);
276 }
277
278 #endif
279