java 五星红旗，java,package net.

java 五星红旗，java,package net.

package net.fants.flag;import java.awt.RenderingHints;import java.awt.geom.AffineTransform;import java.awt.geom.GeneralPath;import javax.swing.JFrame;public class NationalFlag extends JFrame {    private int width = 288,height = width/3*2;      private double maxR = 0.15, minR = 0.05;      private double maxX = 0.50, maxY = 0.50;      private double[] minX = {0.75, 0.85, 0.85, 0.75};      private double[] minY = {0.35, 0.45, 0.60, 0.70};      public NationalFlag() {        setTitle("国旗  - by fants(铂金小鸟)");        setDefaultCloseOperation(EXIT_ON_CLOSE);    }    @Override    public void paint(java.awt.Graphics graphics) {        super.paint(graphics);        java.awt.Graphics2D g = (java.awt.Graphics2D)graphics;        g.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);        //棋面        g.setColor(java.awt.Color.red);        g.fillRect(50, 50, width, height);        g.setColor(java.awt.Color.yellow);        //画大星星        double ox = height*maxX, oy = height*maxY;        g.fill(createPentacle(ox,oy,height*maxR,-Math.PI/2));          //画小星星        for(int idx =0;idx < 4;idx ++){              double sx = minX[idx]*height, sy = minY[idx]*height;              double theta = Math.atan2(oy-sy,ox-sx);              g.fill(createPentacle(sx,sy,height*minR,theta));          }      }    /**     * 创建一个五角星形状. 该五角星的中心坐标为(sx,sy),中心到顶点的距离为radius,其中某个顶点与中心的连线的偏移角度为theta(弧度)     *      * @return pentacle 一个☆     */    public static java.awt.Shape createPentacle(double sx, double sy, double radius,double theta) {        final double arc = Math.PI / 5;        final double rad = Math.sin(Math.PI / 10) / Math.sin(3 * Math.PI / 10);        GeneralPath path = new GeneralPath();        path.moveTo(1, 0);        for (int idx = 0; idx < 5; idx++) {            path.lineTo(rad * Math.cos((1 + 2 * idx) * arc),rad * Math.sin((1 + 2 * idx) * arc));            path.lineTo(Math.cos(2 * (idx + 1) * arc),Math.sin(2 * (idx + 1) * arc));        }        path.closePath();        AffineTransform atf = AffineTransform.getScaleInstance(radius, radius);        atf.translate(sx / radius, sy / radius);        atf.rotate(theta);        return atf.createTransformedShape(path);    }    public static void main(String[] args) {        NationalFlag flag = new NationalFlag();        flag.setBounds(100, 100, 400, 400);        flag.setVisible(true);    }}//该片段来自于http://byrx.net