种子填充算法原理在网上很多地方都能找到，这篇是继上篇扫描线算法后另一种填充算法，直接上实现代码啦0.0
我的实现只是实现了种子填充算法，但是运行效率不快，如果大佬有改进方法，欢迎和我交流，谢谢！
最后还是贴个截图（先在面板里点击点，鼠标移出面板填充）：
package PolygonScanningAndFilling;
public class location {
public int x;
public int y;
}
package PolygonScanningAndFilling; import java.util.ArrayList;
import java.util.Iterator;
import java.util.Stack;
import java.util.Timer;
import java.util.TimerTask;
import javax.swing.*;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.io.IOException; public class SeedFulling extends JPanel { static int X0;
static int Y0;
static int X1;
static int Y1;
static int a[]=new int [10]; //保存点击的10个x坐标
static int b[]=new int [10]; //保存点击的10个y坐标
static int index=0;
static int time=0;
static int time2=0;
static boolean add;
ArrayList<Point>allPoint=new ArrayList<Point>();
ArrayList<Point>drawPoint=new ArrayList<Point>();
@Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
this.addMouseListener(new MouseAdapter() {
public void mouseExited(MouseEvent e) {
time++;
repaint(); }
public void mouseClicked(MouseEvent e) {
allPoint.clear();
if(e.getButton() == e.BUTTON1) {
add=true;
if(index!=0)
{
for(int i=0;i<index;i++)
{
if(a[i]==e.getX()&&b[i]==e.getY())
add=false;
}
}
if(add)
{ a[index]=e.getX();
b[index]=e.getY(); System.out.println("坐标为("+a[index]+","+b[index]+")");
index++; //frame.setVisible(true);
repaint();
System.out.print(time2);
if(time2==0)
time2++;
}
} // if(e.getButton() == e.BUTTON3)
// {
//
// }
} }); Graphics2D g2d = (Graphics2D)g; int Ymax=0;
for(int i=0;i<b.length;i++)
{
if(Ymax<b[i])
Ymax=b[i];
}
// System.out.println("Ymax"+Ymax); /*
* 画出多边形
*/
if(time2!=0)
{ int Sum=0;
for(;Sum<=index;Sum++) {
if(Sum==index-1)
{
drawLine(a[Sum], b[Sum], a[0],b[0],g2d); break;
}
else
{
drawLine(a[Sum], b[Sum], a[Sum+1],b[Sum+1],g2d); } }
}
/*
* 得到边界点
*/ if(time!=0) {
boolean spanNeedFill;
location l=new location();
l.x=a[0]+10;
l.y=b[0]+10;
Stack<location> stack=new Stack<location>(); //将第一个点压入栈
stack.push(l);
int a=0;
while(!stack.empty())
{
a++;
System.out.print("第"+a+"次");
location lo=stack.pop();
int x=lo.x;
int y=lo.y;
if(a>50)
{ System.out.println("开始画上时x"+x);
System.out.println("开始画上时y"+y);
}
// System.out.print("y"+y); while(!allPoint.contains(new Point(x,y))&&!drawPoint.contains(new Point(x,y)))
{
//System.out.print(x);
drawPoint.add(new Point(x,y));
//System.out.println("需画点"+x+","+y);
x++;
} int xr=x-1;
x=lo.x-1;
while(!allPoint.contains(new Point(x,y))&&!drawPoint.contains(new Point(x,y)))
{
drawPoint.add(new Point(x,y));
//System.out.println("需画点"+x+","+y);
//g2d.drawString(".", x,y);
x--;
} int xl=x+1;
//处理上面的扫描线
x=xl;
y=y+1; while(x<=xr) { spanNeedFill=false;
while(!allPoint.contains(new Point(x,y))&&!drawPoint.contains(new Point(x,y)))
{
spanNeedFill=true;
x++; //System.out.println("上扫描线边界为"+x);
}
if(spanNeedFill)
{
//System.out.print("入栈1"); location lc=new location();
lc.x=x-1;
lc.y=y;
stack.push(lc);
//System.out.println("入栈1，此时 x="+lc.x);
//System.out.println("入栈1，此时 y="+lc.y);
spanNeedFill=false; }
while(allPoint.contains(new Point(x,y))||drawPoint.contains(new Point(x,y))&&x<=xr)
x++;
} //下扫描线
x=xl;
y=y-2;
while(x<=xr)
{
spanNeedFill=false;
while(!allPoint.contains(new Point(x,y))&&!drawPoint.contains(new Point(x,y)))
{
spanNeedFill=true;
x++;
}
if(spanNeedFill)
{
//System.out.print("入栈2");
lo.x=x-1;
lo.y=y;
stack.push(lo);
System.out.print("入栈2");
spanNeedFill=false; }
while(allPoint.contains(new Point(x,y))||drawPoint.contains(new Point(x,y))&&x<=xr)
x++; }
}
for(int i=0;i<drawPoint.size();i++)
{
//System.out.println("画的y"+p.y);
Point p=drawPoint.get(i);
System.out.println("画的x"+p.x+"画的y"+p.y);
g2d.drawString(".",p.x,p.y); }
} } private static void createAndShowGUI() {
JFrame frame = new JFrame(); frame.setLocationRelativeTo(null); frame.setLayout(null);
JPanel jp=new JPanel();
frame.setVisible(true); frame.setContentPane(new SeedFulling()); frame.setSize(600, 600);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLocationRelativeTo(null);
frame.setVisible(true);
} public void drawLine(int x0,int y0,int x1,int y1,Graphics2D g) {
int x = x0;
int y = y0; int w = x1 - x0;
int h = y1 - y0; int dx1 = w < 0 ? -1: (w > 0 ? 1 : 0);
int dy1 = h < 0 ? -1: (h > 0 ? 1 : 0); int dx2 = w < 0 ? -1: (w > 0 ? 1 : 0);
int dy2 = 0; int fastStep = Math.abs(w);
int slowStep = Math.abs(h);
if (fastStep <=slowStep) {
fastStep= Math.abs(h);
slowStep= Math.abs(w); dx2= 0;
dy2= h < 0 ? -1 : (h > 0 ? 1 : 0);
}
int numerator = fastStep>> 1; for (int i = 0; i <=fastStep; i++) { g.drawString(".", x, y);
Point p=new Point(x,y);
allPoint.add(p);
numerator+= slowStep;
if (numerator >=fastStep) {
numerator-= fastStep;
x+= dx1;
y+= dy1;
}else {
x+= dx2;
y+= dy2;
}
}
} public static void main(String[] args) throws IOException { createAndShowGUI(); }
}
