Java实现矩形网格等值线绘制代码示例

生成等值线的java代码
最近需要做一个生成等值线的组件，看了一些资料，等值线的构造主要可分为两种方法，一是构造三角形，二是构造网格正方形。研究了一下，看到了一个很好的算法，先贴出来，等过两天做出组件来了再具体讨论，也希望有想法或者类似经验的朋友跟贴讨论。


 程序代码

package cn.edu.xaut.transfer.end;

public class Conrec {

    private double  []  h   =  new double [5];
    private int     []  sh  =  new int    [5];
    private double  []  xh  =  new double [5];
    private double  []  yh  =  new double [5];
    
    // Object that knows how to draw the contour
    private Render render = null;

    /** Creates new Conrec */
    public  Conrec(Render render) throws Exception {
        if (render == null){
            throw new Exception ("Render null");
        }
        this.render = render;
    }
    

    /**
     *     contour is a contouring subroutine for rectangularily spaced data 
     *

     *     It emits calls to a line drawing subroutine supplied by the user
     *     which draws a contour map corresponding to real*4data on a randomly
     *     spaced rectangular grid. The coordinates emitted are in the same
     *     units given in the x() and y() arrays.
     *
     *     Any number of contour levels may be specified but they must be
     *     in order of increasing value.
     *
     *
     * @param d  - matrix of data to contour
     * @param ilb,iub,jlb,jub - index bounds of data matrix
     *
     *             The following two, one dimensional arrays (x and y) contain the horizontal and
     *             vertical coordinates of each sample points.
     * @param x  - data matrix column coordinates
     * @param y  - data matrix row coordinates
     * @param nc - number of contour levels
     * @param z  - contour levels in increasing order.
     * 
     */
    public void contour(double [][] d, int ilb, int iub, int jlb, int jub, double [] x, double [] y, int nc, double [] z) {
        int         m1;
        int         m2;
        int         m3;
        int         case_value;
        double      dmin;
        double      dmax;
        double      x1 = 0.0;
        double      x2 = 0.0;
        double      y1 = 0.0;