Program Listing for File Perlin.hpp
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#pragma once
#include <vector>
//
// double fade(double t);
// double lerp(double t, double a, double b);
// double grad(int hash, double x, double y, double z);
// double perlin_noise(float x, float y, std::vector<int>& p);
//
// std::vector<int> myFunction(int value, double bullshit) {
// std::vector<int> r{ 2,3,4,4 };
// return r;
// }
//
// void get_Permutation_Vector(std::vector<int>* pVectorPointer);
//
//
//
// fade(t)= t^3 (10 + t* (t* 6 - 15))
double fade(double t) { return t * t * t * (t * (t * 6 - 15) + 10); };
// linear interpolation between a and b: For polishing
// t = [0,1] is the persentage of the distance bewteen a and b
double lerp(double t, double a, double b) { return a + (b - a) * t; }
//
double grad(int hash, double x, double y, double z)
{
int h = hash & 15;// CONVERT LO 4 BITS OF HASH CODE
double u = h < 8 ? x : y,// INTO 12 GRADIENT DIRECTIONS.
v = h < 4 ? y
: h == 12 || h == 14 ? x
: z;
return ((h & 1) == 0 ? u : -u) + ((h & 2) == 0 ? v : -v);
}
// generate Perlin noise
// Parameter:
// p is (psyodo) "random" value
double perlin_noise(float x, float y, std::vector<int> &p)
{
int z = 0.5;
// x,y,z abrunden und mit 1111 1111 verunden == modulo 255
int X = (int)floor(x) & 255,// FIND UNIT CUBE THAT
Y = (int)floor(y) & 255,// CONTAINS POINT.
Z = (int)floor(z) & 255;
// Kommastellen
x -= floor(x);// FIND RELATIVE X,Y,Z
y -= floor(y);// OF POINT IN CUBE.
z -= floor(z);
double u = fade(x),// COMPUTE FADE CURVES
v = fade(y),// FOR EACH OF X,Y,Z.
w = fade(z);
int A = p[X] + Y, AA = p[A] + Z, AB = p[A + 1] + Z,// HASH COORDINATES OF
B = p[X + 1] + Y, BA = p[B] + Z,
BB = p[B + 1] + Z;// THE 8 CUBE CORNERS,
// return perlin noise of x and y
return lerp(w,
lerp(v,
lerp(u,
grad(p[AA], x, y, z),// AND ADD
grad(p[BA], x - 1, y, z)),// BLENDED
lerp(u,
grad(p[AB], x, y - 1, z),// RESULTS
grad(p[BB], x - 1, y - 1, z))),// FROM 8
lerp(v,
lerp(u,
grad(p[AA + 1], x, y, z - 1),// CORNERS
grad(p[BA + 1], x - 1, y, z - 1)),// OF CUBE
lerp(u, grad(p[AB + 1], x, y - 1, z - 1), grad(p[BB + 1], x - 1, y - 1, z - 1))));
}
//
// void get_Permutation_Vector(std::vector<int>* permVectorPointer) {
// permVectorPointer->clear();
//
// std::vector<int> permutation = { 151,160,137,91,90,15,
// 131,13,201,95,96,53,194,233,7,225,140,36,103,30,69,142,8,99,37,240,21,10,23,
// 190,
// 6,148,247,120,234,75,0,26,197,62,94,252,219,203,117,35,11,32,57,177,33,
// 88,237,149,56,87,174,20,125,136,171,168,
// 68,175,74,165,71,134,139,48,27,166,
// 77,146,158,231,83,111,229,122,60,211,133,230,220,105,92,41,55,46,245,40,244,
// 102,143,54, 65,25,63,161, 1,216,80,73,209,76,132,187,208,
// 89,18,169,200,196, 135,130,116,188,159,86,164,100,109,198,173,186,
// 3,64,52,217,226,250,124,123,
// 5,202,38,147,118,126,255,82,85,212,207,206,59,227,47,16,58,17,182,189,28,42,
// 223,183,170,213,119,248,152, 2,44,154,163, 70,221,153,101,155,167,
// 43,172,9, 129,22,39,253, 19,98,108,110,79,113,224,232,178,185,
// 112,104,218,246,97,228, 251,34,242,193,238,210,144,12,191,179,162,241,
// 81,51,145,235,249,14,239,107, 49,192,214, 31,181,199,106,157,184,
// 84,204,176,115,121,50,45,127, 4,150,254,
// 138,236,205,93,222,114,67,29,24,72,243,141,128,195,78,66,215,61,156,180
// };
//
// for (int j = 0; j < 2; j++)
// for (int i = 0; i < 256; i++) {
// permVectorPointer->push_back(permutation[i]);
// }
//}
// initialise 2x permutation of a hard coded 256 int vector
// std::vector<int> PERLIN_H::kansei() {
std::vector<int> getPermutationVector()
{
std::vector<int> p;
std::vector<int> permutation = { 151,
160,
137,
91,
90,
15,
131,
13,
201,
95,
96,
53,
194,
233,
7,
225,
140,
36,
103,
30,
69,
142,
8,
99,
37,
240,
21,
10,
23,
190,
6,
148,
247,
120,
234,
75,
0,
26,
197,
62,
94,
252,
219,
203,
117,
35,
11,
32,
57,
177,
33,
88,
237,
149,
56,
87,
174,
20,
125,
136,
171,
168,
68,
175,
74,
165,
71,
134,
139,
48,
27,
166,
77,
146,
158,
231,
83,
111,
229,
122,
60,
211,
133,
230,
220,
105,
92,
41,
55,
46,
245,
40,
244,
102,
143,
54,
65,
25,
63,
161,
1,
216,
80,
73,
209,
76,
132,
187,
208,
89,
18,
169,
200,
196,
135,
130,
116,
188,
159,
86,
164,
100,
109,
198,
173,
186,
3,
64,
52,
217,
226,
250,
124,
123,
5,
202,
38,
147,
118,
126,
255,
82,
85,
212,
207,
206,
59,
227,
47,
16,
58,
17,
182,
189,
28,
42,
223,
183,
170,
213,
119,
248,
152,
2,
44,
154,
163,
70,
221,
153,
101,
155,
167,
43,
172,
9,
129,
22,
39,
253,
19,
98,
108,
110,
79,
113,
224,
232,
178,
185,
112,
104,
218,
246,
97,
228,
251,
34,
242,
193,
238,
210,
144,
12,
191,
179,
162,
241,
81,
51,
145,
235,
249,
14,
239,
107,
49,
192,
214,
31,
181,
199,
106,
157,
184,
84,
204,
176,
115,
121,
50,
45,
127,
4,
150,
254,
138,
236,
205,
93,
222,
114,
67,
29,
24,
72,
243,
141,
128,
195,
78,
66,
215,
61,
156,
180 };
for (int j = 0; j < 2; j++)
for (int i = 0; i < 256; i++) { p.push_back(permutation[i]); }
return p;
}