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http://image.kilho.net/?pk=1420781創建自然柏林噪聲
我想使用Perlin雜創建地形。
但我總是得到以上的噪音。
http://image.kilho.net/?pk=1420774
我想是最後（第7）圖像。
但我的噪聲圖像看起來像第4或第5圖像。
這裏是我的代碼（JAVA）
int seed;
public Noise() {
Random ran = new Random();
seed = ran.nextInt();
}
/**
* Brut noise generator using pseudo-random
*/
public double noise(int x,int y)
{
x=x + y * seed;
x=((x<<13)^x);
double t=(x * (x * x * 15731 + 789221) + 1376312589) & 0x7fffffff;
return 1-t*0.000000000931322574615478515625;
}
/**
* Smoothed noise generator using 9 brut noise
*/
public double sNoise(int x,int y)
{
double corners = (noise(x-1, y-1)+noise(x+1, y-1)+noise(x-1, y+1)+noise(x+1, y+1)) * 0.0625;
double sides = (noise(x-1, y) +noise(x+1, y) +noise(x, y-1) +noise(x, y+1)) *0.125;
double center = noise(x, y) *0.25;
return corners + sides + center;
}
/**
* Linear Interpolator
*
* @param a value 1
* @param b value 2
* @param x interpolator factor
*
* @return value interpolated from a to b using x factor by linear interpolation
*/
public double lInterpoleLin(double a,double b,double x)
{
return a*(1-x) + b*x;
}
/**
* Cosine Interpolator
*
* @param a value 1
* @param b value 2
* @param x interpolator factor
*
* @return value interpolated from a to b using x factor by cosin interpolation
*/
public double lInterpoleCos(double a,double b,double x)
{
double ft = x * 3.1415927;
double f = (1 - Math.cos(ft)) * .5;
return a*(1-f) + b*f;
}
/**
* Smooth noise generator with two input 2D
* <br>
* You may change the interpolation method : cosin , linear , cubic
* </br>
* @param x x parameter
* @param y y parameter
*
* @return value of smoothed noise for 2d value x,y
*/
public double iNoise(double x,double y)
{
int iX=(int)x;
int iY=(int)y;
double dX=x-iX;
double dY=y-iY;
double p1=sNoise(iX,iY);
double p2=sNoise(iX+1,iY);
double p3=sNoise(iX,iY+1);
double p4=sNoise(iX+1,iY+1);
double i1=lInterpoleLin(p1,p2,dX);
double i2=lInterpoleLin(p3,p4,dX);
return lInterpoleLin(i1,i2,dY);
}
/**
* Perlin noise generator for two input 2D
*
* @param x x parameter
* @param y y parameter
* @param octave maximum octave/harmonic
* @param persistence noise persitence
* @return perlin noise value for given entry
*/
public double pNoise(double x,double y,double persistence,int octave)
{
double result;
double amplitude=1;
int frequence=1;
result=0;
for(int n=0;n<octave;n++)
{
result+=iNoise(x*frequence,y*frequence)*amplitude;
frequence<<=1;
amplitude*=persistence;
}
return result;
}
}