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docs: update the whole repository

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* fix some bugs
* delete duplicate files
* format code
This commit is contained in:
yanglbme
2019-05-09 19:32:54 +08:00
parent 163db8521a
commit 29948363da
368 changed files with 4372 additions and 30841 deletions
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38
Others/PerlinNoise.java
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@ -1,3 +1,5 @@
package Others;
import java.util.Random;
import java.util.Scanner;
@ -6,11 +8,11 @@ import java.util.Scanner;
*/
public class PerlinNoise {
/**
* @param width width of noise array
* @param height height of noise array
* @param width width of noise array
* @param height height of noise array
* @param octaveCount numbers of layers used for blending noise
* @param persistence value of impact each layer get while blending
* @param seed used for randomizer
* @param seed used for randomizer
* @return float array containing calculated "Perlin-Noise" values
*/
static float[][] generatePerlinNoise(int width, int height, int octaveCount, float persistence, long seed) {
@ -20,14 +22,14 @@ public class PerlinNoise {
Random random = new Random(seed);
//fill base array with random values as base for noise
for(int x = 0; x < width; x++) {
for(int y = 0; y < height; y++) {
for (int x = 0; x < width; x++) {
for (int y = 0; y < height; y++) {
base[x][y] = random.nextFloat();
}
}
//calculate octaves with different roughness
for(int octave = 0; octave < octaveCount; octave++) {
for (int octave = 0; octave < octaveCount; octave++) {
noiseLayers[octave] = generatePerlinNoiseLayer(base, width, height, octave);
}
@ -35,12 +37,12 @@ public class PerlinNoise {
float totalAmplitude = 0f;
//calculate perlin noise by blending each layer together with specific persistence
for(int octave = octaveCount - 1; octave >= 0; octave--) {
for (int octave = octaveCount - 1; octave >= 0; octave--) {
amplitude *= persistence;
totalAmplitude += amplitude;
for(int x = 0; x < width; x++) {
for(int y = 0; y < height; y++) {
for (int x = 0; x < width; x++) {
for (int y = 0; y < height; y++) {
//adding each value of the noise layer to the noise
//by increasing amplitude the rougher noises will have more impact
perlinNoise[x][y] += noiseLayers[octave][x][y] * amplitude;
@ -49,7 +51,7 @@ public class PerlinNoise {
}
//normalize values so that they stay between 0..1
for(int x = 0; x < width; x++) {
for (int x = 0; x < width; x++) {
for (int y = 0; y < height; y++) {
perlinNoise[x][y] /= totalAmplitude;
}
@ -59,8 +61,8 @@ public class PerlinNoise {
}
/**
* @param base base random float array
* @param width width of noise array
* @param base base random float array
* @param width width of noise array
* @param height height of noise array
* @param octave current layer
* @return float array containing calculated "Perlin-Noise-Layer" values
@ -72,13 +74,13 @@ public class PerlinNoise {
int period = 1 << octave; //2^k
float frequency = 1f / period; // 1/2^k
for(int x = 0; x < width; x++) {
for (int x = 0; x < width; x++) {
//calculates the horizontal sampling indices
int x0 = (x / period) * period;
int x1 = (x0 + period) % width;
float horizintalBlend = (x - x0) * frequency;
for(int y = 0; y < height; y++) {
for (int y = 0; y < height; y++) {
//calculates the vertical sampling indices
int y0 = (y / period) * period;
int y1 = (y0 + period) % height;
@ -99,8 +101,8 @@ public class PerlinNoise {
}
/**
* @param a value of point a
* @param b value of point b
* @param a value of point a
* @param b value of point b
* @param alpha determine which value has more impact (closer to 0 -> a, closer to 1 -> b)
* @return interpolated value
*/
@ -143,8 +145,8 @@ public class PerlinNoise {
final int length = chars.length;
final float step = 1f / length;
//output based on charset
for(int x = 0; x < width; x++) {
for(int y = 0; y < height; y++) {
for (int x = 0; x < width; x++) {
for (int y = 0; y < height; y++) {
float value = step;
float noiseValue = perlinNoise[x][y];