Java 中分形图的几种方法详解

/**
 * 复数类
 * @author CBS
 */
public class Complex {
  
  public double r;
  public double i;
  
  public Complex(double real,double image){
    this.r=real;
    this.i=image;
  }
  //取复数的模
  public double modulus(){
    return Math.sqrt(r*r+i*i);
  }
  //复数的加法
  public Complex add(Complex z){
    double addr=r+z.r;
    double addi=i+z.i;
    return new Complex(addr,addi);
  }
  //复数的乘法
  public Complex mul(Complex z){
    double mulr=r*z.r-i*z.i;
    double muli=i*z.r+r*z.i;
    return new Complex(mulr,muli);
  }
}

// 求最大的迭代次数的算法，时间逃逸算法
  public int mand(Complex z, int maxIte) {
    Complex curComp = new Complex(0, 0);
    for (int i = 0; i < maxIte; i++) {
      if (curComp.modulus() > 2)
        return i;
      curComp = curComp.mul(curComp).add(z);
    }
    return maxIte;
  }

// 画图的算法
  public void drawMand(Complex z, double scale, int MaxIte) {
    double pixUnit = 3 / (1080 * scale);
    double startx = z.r - 1080 * pixUnit / 2;
    double starty = z.i - 720 * pixUnit / 2;

    for (int i = 0; i < 1080; i++) {
      for (int j = 0; j < 720; j++) {
        double x0 = startx + i * pixUnit;
        double y0 = starty + j * pixUnit;
        Complex curComplex = new Complex(x0, y0);
        int time = mand(curComplex, MaxIte);
        if (time == MaxIte) {
          double x = x0 * 150 + 500;// 扩大出现方格
          double y = y0 * 150 + 500;
          g.drawLine((int) x, (int) y, (int) x, (int) y);
        }
      }
    }
  }