1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
use std::num::Wrapping;
pub struct PerlinNoise2D {
octaves: i32,
amplitude: f64,
frequency: f64,
persistence: f64,
lacunarity: f64,
scale: (f64, f64),
bias: f64,
seed: i32,
}
impl PerlinNoise2D {
pub fn new(
octaves: i32,
amplitude: f64,
frequency: f64,
persistence: f64,
lacunarity: f64,
scale: (f64, f64),
bias: f64,
seed: i32,
) -> Self {
Self {
octaves,
amplitude,
frequency,
persistence,
lacunarity,
scale,
bias,
seed,
}
}
pub fn get_octaves(&self) -> i32 {
self.octaves
}
pub fn get_amplitude(&self) -> f64 {
self.amplitude
}
pub fn get_frequency(&self) -> f64 {
self.frequency
}
pub fn get_persistence(&self) -> f64 {
self.persistence
}
pub fn get_lacunarity(&self) -> f64 {
self.lacunarity
}
pub fn get_scale(&self) -> (f64, f64) {
self.scale
}
pub fn get_bias(&self) -> f64 {
self.bias
}
pub fn get_seed(&self) -> i32 {
self.seed
}
pub fn set_octaves(&mut self, octaves: i32) {
self.octaves = octaves;
}
pub fn set_amplitude(&mut self, amplitude: f64) {
self.amplitude = amplitude;
}
pub fn set_frequency(&mut self, frequency: f64) {
self.frequency = frequency;
}
pub fn set_persistence(&mut self, persistence: f64) {
self.persistence = persistence;
}
pub fn set_lacunarity(&mut self, lacunarity: f64) {
self.lacunarity = lacunarity;
}
pub fn set_scale(&mut self, scale: (f64, f64)) {
self.scale = scale;
}
pub fn set_bias(&mut self, bias: f64) {
self.bias = bias;
}
pub fn set_seed(&mut self, seed: i32) {
self.seed = seed;
}
pub fn get_noise(&self, x: f64, y: f64) -> f64 {
self.bias + self.amplitude * self.total(x / self.scale.0, y / self.scale.1)
}
fn total(&self, x: f64, y: f64) -> f64 {
let mut t = 0.0;
let mut amp = 1.0;
let mut freq = self.frequency;
for _ in 0..self.octaves {
t += self.get_value(y * freq + self.seed as f64, x * freq + self.seed as f64) * amp;
amp *= self.persistence;
freq *= self.lacunarity;
}
t
}
fn interpolate(&self, x: f64, y: f64, a: f64) -> f64 {
let neg_a: f64 = 1.0 - a;
let neg_a_sqr: f64 = neg_a * neg_a;
let fac1: f64 = 3.0 * (neg_a_sqr) - 2.0 * (neg_a_sqr * neg_a);
let a_sqr: f64 = a * a;
let fac2: f64 = 3.0 * a_sqr - 2.0 * (a_sqr * a);
x * fac1 + y * fac2
}
fn noise(&self, x: i32, y: i32) -> f64 {
let mut n: i64 = x as i64 + y as i64 * 57;
n = (n << 13) ^ n;
let t = Wrapping(n) * Wrapping(n) * Wrapping(n * 15731 + 789221) + Wrapping(1376312589);
let t = t.0 & 0x7fffffff;
1.0 - (t as f64) * 0.931322574615478515625e-9
}
fn get_value(&self, x: f64, y: f64) -> f64 {
let x_int: i32 = x as i32;
let y_int: i32 = y as i32;
let x_frac: f64 = x - f64::floor(x);
let y_frac: f64 = y - f64::floor(y);
let n01: f64 = self.noise(x_int - 1, y_int - 1);
let n02: f64 = self.noise(x_int + 1, y_int - 1);
let n03: f64 = self.noise(x_int - 1, y_int + 1);
let n04: f64 = self.noise(x_int + 1, y_int + 1);
let n05: f64 = self.noise(x_int - 1, y_int);
let n06: f64 = self.noise(x_int + 1, y_int);
let n07: f64 = self.noise(x_int, y_int - 1);
let n08: f64 = self.noise(x_int, y_int + 1);
let n09: f64 = self.noise(x_int, y_int);
let n12: f64 = self.noise(x_int + 2, y_int - 1);
let n14: f64 = self.noise(x_int + 2, y_int + 1);
let n16: f64 = self.noise(x_int + 2, y_int);
let n23: f64 = self.noise(x_int - 1, y_int + 2);
let n24: f64 = self.noise(x_int + 1, y_int + 2);
let n28: f64 = self.noise(x_int, y_int + 2);
let n34: f64 = self.noise(x_int + 2, y_int + 2);
let x0y0: f64 = 0.0625 * (n01 + n02 + n03 + n04) + 0.125 * (n05 + n06 + n07 + n08) + 0.25 * (n09);
let x1y0: f64 = 0.0625 * (n07 + n12 + n08 + n14) + 0.125 * (n09 + n16 + n02 + n04) + 0.25 * (n06);
let x0y1: f64 = 0.0625 * (n05 + n06 + n23 + n24) + 0.125 * (n03 + n04 + n09 + n28) + 0.25 * (n08);
let x1y1: f64 = 0.0625 * (n09 + n16 + n28 + n34) + 0.125 * (n08 + n14 + n06 + n24) + 0.25 * (n04);
let v1: f64 = self.interpolate(x0y0, x1y0, x_frac);
let v2: f64 = self.interpolate(x0y1, x1y1, x_frac);
let fin: f64 = self.interpolate(v1, v2, y_frac);
return fin;
}
}