Java種子填充演算法 四向和八向
阿新 • • 發佈:2018-11-26
種子填充演算法多用於計算機對圖形的處理。例如ps中填充區域一樣。當我們要填充某一塊區域,首先我們要讓電腦識別出你要填充的每個畫素點,種子演算法通過給定種子的座標獲取該畫素的顏色值,通過對比顏色資訊來判斷周圍的畫素是否是我們要選擇的。
接下來我們用一個字元陣列來代表我們的圖片,*號的點則是我們要選中的畫素,選擇後我們則將他改成#。
第一種:四向填充
我們沒給定一個種子,我們則只獲取左、上、右、下四個點。通過遞迴或迴圈處理所有的點。但是用遞迴會存在遞迴的深度問題,當我們的圖片足夠大時,Java虛擬機器就會報出棧溢位的錯誤!
所以我們選取迴圈+佇列的方式。我們都知道佇列有個特性:先進先出!當我們根據種子點獲取周圍四個點加入佇列,下一次迴圈則從佇列頭部去除一個點作為下一次的種子,並刪除他,依次這樣迴圈直到佇列大小為零則停止。
Demo1.COL、Demo1.ROW為定義字元陣列的行列
/** * 四向 * @param seed */ public void DemoFill4(Point se) { Point seed = se; do { //左 if(0<=(seed.x-1)&&(seed.x-1)<Demo1.ROW&&0<=(seed.y)&&(seed.y)<Demo1.COL&&!point[seed.x-1][seed.y].equals(c)) { point[seed.x-1][seed.y] = c; queue.offer(new Point(seed.x-1,seed.y)); } //上 if(0<=(seed.x)&&(seed.x)<Demo1.ROW&&0<=(seed.y-1)&&(seed.y-1)<Demo1.COL&&!point[seed.x][seed.y-1].equals(c)) { point[seed.x][seed.y-1] = c; queue.offer(new Point(seed.x,seed.y-1)); } //右 if(0<=(seed.x+1)&&(seed.x+1)<Demo1.ROW&&0<=(seed.y)&&(seed.y)<Demo1.COL&&!point[seed.x+1][seed.y].equals(c)) { point[seed.x+1][seed.y] = c; queue.offer(new Point(seed.x+1,seed.y)); } //下 if(0<=(seed.x)&&(seed.x)<Demo1.ROW&&0<=(seed.y+1)&&(seed.y+1)<Demo1.COL&&!point[seed.x][seed.y+1].equals(c)) { point[seed.x][seed.y+1] = c; queue.offer(new Point(seed.x,seed.y+1)); } if(queue.size()>0) { point[seed.x][seed.y] = c; Point s = (Point) queue.poll(); point[s.x][s.y] = c; seed = s; }else { return; } }while(true); }
為了提高演算法的效能,則可以在加入周圍點的同時也改變周圍點。
第二種:八向填充 八向填充和四向不同的地方就是他選取了八個方向的點主要是解決邊角問題。
/** * 八向 * @param seed */ public void DemoFill8(Point se) { Point seed = se; do { //左 if(0<=(seed.x-1)&&(seed.x-1)<Demo1.ROW&&0<=(seed.y)&&(seed.y)<Demo1.COL&&!point[seed.x-1][seed.y].equals(c)) { point[seed.x-1][seed.y] = c; queue.offer(new Point(seed.x-1,seed.y)); } //左上 if(0<=(seed.x-1)&&(seed.x-1)<Demo1.ROW&&0<=(seed.y-1)&&(seed.y-1)<Demo1.COL&&!point[seed.x-1][seed.y-1].equals(c)) { point[seed.x-1][seed.y-1] = c; queue.offer(new Point(seed.x-1,seed.y-1)); } //上 if(0<=(seed.x)&&(seed.x)<Demo1.ROW&&0<=(seed.y-1)&&(seed.y-1)<Demo1.COL&&!point[seed.x][seed.y-1].equals(c)) { point[seed.x][seed.y-1] = c; queue.offer(new Point(seed.x,seed.y-1)); } //右上 if(0<=(seed.x+1)&&(seed.x+1)<Demo1.ROW&&0<=(seed.y-1)&&(seed.y-1)<Demo1.COL&&!point[seed.x+1][seed.y-1].equals(c)) { point[seed.x+1][seed.y-1] = c; queue.offer(new Point(seed.x+1,seed.y-1)); } //右 if(0<=(seed.x+1)&&(seed.x+1)<Demo1.ROW&&0<=(seed.y)&&(seed.y)<Demo1.COL&&!point[seed.x+1][seed.y].equals(c)) { point[seed.x+1][seed.y] = c; queue.offer(new Point(seed.x+1,seed.y)); } //右下 if(0<=(seed.x+1)&&(seed.x+1)<Demo1.ROW&&0<=(seed.y+1)&&(seed.y+1)<Demo1.COL&&!point[seed.x+1][seed.y+1].equals(c)) { point[seed.x+1][seed.y+1] = c; queue.offer(new Point(seed.x+1,seed.y+1)); } //下 if(0<=(seed.x)&&(seed.x)<Demo1.ROW&&0<=(seed.y+1)&&(seed.y+1)<Demo1.COL&&!point[seed.x][seed.y+1].equals(c)) { point[seed.x][seed.y+1] = c; queue.offer(new Point(seed.x,seed.y+1)); } //左下 if(0<=(seed.x-1)&&(seed.x-1)<Demo1.ROW&&0<=(seed.y+1)&&(seed.y+1)<Demo1.COL&&!point[seed.x-1][seed.y+1].equals(c)) { point[seed.x-1][seed.y+1] = c; queue.offer(new Point(seed.x-1,seed.y+1)); } if(queue.size()>0) { point[seed.x][seed.y] = c; Point s = (Point) queue.poll(); point[s.x][s.y] = c; seed = s; }else { return; } }while(true); }
完整樣例如下:
Point.java
package com.lb.test;
/**
* 物件點
* @author lanbing
* @date 2018年9月17日
*
*/
public class Point {
public int x;
public int y;
public Point(int x, int y) {
super();
this.x = x;
this.y = y;
}
}
Fill.java
package com.lb.test;
import java.util.LinkedList;
import java.util.Queue;
/**
* 四向,八向
* @author lanbing
* @date 2018年9月17日
*
*/
public class Fill {
public String[][] point;
public String c;
Queue<Point> queue = new LinkedList<Point>();
public Fill(String[][] point, String c) {
super();
this.point = point;
this.c = c;
}
/**
* 四向
* @param seed
*/
public void DemoFill4(Point se) {
Point seed = se;
do {
//左
if(0<=(seed.x-1)&&(seed.x-1)<Demo1.ROW&&0<=(seed.y)&&(seed.y)<Demo1.COL&&!point[seed.x-1][seed.y].equals(c)) {
point[seed.x-1][seed.y] = c;
queue.offer(new Point(seed.x-1,seed.y));
}
//上
if(0<=(seed.x)&&(seed.x)<Demo1.ROW&&0<=(seed.y-1)&&(seed.y-1)<Demo1.COL&&!point[seed.x][seed.y-1].equals(c)) {
point[seed.x][seed.y-1] = c;
queue.offer(new Point(seed.x,seed.y-1));
}
//右
if(0<=(seed.x+1)&&(seed.x+1)<Demo1.ROW&&0<=(seed.y)&&(seed.y)<Demo1.COL&&!point[seed.x+1][seed.y].equals(c)) {
point[seed.x+1][seed.y] = c;
queue.offer(new Point(seed.x+1,seed.y));
}
//下
if(0<=(seed.x)&&(seed.x)<Demo1.ROW&&0<=(seed.y+1)&&(seed.y+1)<Demo1.COL&&!point[seed.x][seed.y+1].equals(c)) {
point[seed.x][seed.y+1] = c;
queue.offer(new Point(seed.x,seed.y+1));
}
if(queue.size()>0) {
point[seed.x][seed.y] = c;
Point s = (Point) queue.poll();
point[s.x][s.y] = c;
seed = s;
}else {
return;
}
}while(true);
}
/**
* 八向
* @param seed
*/
public void DemoFill8(Point se) {
Point seed = se;
do {
//左
if(0<=(seed.x-1)&&(seed.x-1)<Demo1.ROW&&0<=(seed.y)&&(seed.y)<Demo1.COL&&!point[seed.x-1][seed.y].equals(c)) {
point[seed.x-1][seed.y] = c;
queue.offer(new Point(seed.x-1,seed.y));
}
//左上
if(0<=(seed.x-1)&&(seed.x-1)<Demo1.ROW&&0<=(seed.y-1)&&(seed.y-1)<Demo1.COL&&!point[seed.x-1][seed.y-1].equals(c)) {
point[seed.x-1][seed.y-1] = c;
queue.offer(new Point(seed.x-1,seed.y-1));
}
//上
if(0<=(seed.x)&&(seed.x)<Demo1.ROW&&0<=(seed.y-1)&&(seed.y-1)<Demo1.COL&&!point[seed.x][seed.y-1].equals(c)) {
point[seed.x][seed.y-1] = c;
queue.offer(new Point(seed.x,seed.y-1));
}
//右上
if(0<=(seed.x+1)&&(seed.x+1)<Demo1.ROW&&0<=(seed.y-1)&&(seed.y-1)<Demo1.COL&&!point[seed.x+1][seed.y-1].equals(c)) {
point[seed.x+1][seed.y-1] = c;
queue.offer(new Point(seed.x+1,seed.y-1));
}
//右
if(0<=(seed.x+1)&&(seed.x+1)<Demo1.ROW&&0<=(seed.y)&&(seed.y)<Demo1.COL&&!point[seed.x+1][seed.y].equals(c)) {
point[seed.x+1][seed.y] = c;
queue.offer(new Point(seed.x+1,seed.y));
}
//右下
if(0<=(seed.x+1)&&(seed.x+1)<Demo1.ROW&&0<=(seed.y+1)&&(seed.y+1)<Demo1.COL&&!point[seed.x+1][seed.y+1].equals(c)) {
point[seed.x+1][seed.y+1] = c;
queue.offer(new Point(seed.x+1,seed.y+1));
}
//下
if(0<=(seed.x)&&(seed.x)<Demo1.ROW&&0<=(seed.y+1)&&(seed.y+1)<Demo1.COL&&!point[seed.x][seed.y+1].equals(c)) {
point[seed.x][seed.y+1] = c;
queue.offer(new Point(seed.x,seed.y+1));
}
//左下
if(0<=(seed.x-1)&&(seed.x-1)<Demo1.ROW&&0<=(seed.y+1)&&(seed.y+1)<Demo1.COL&&!point[seed.x-1][seed.y+1].equals(c)) {
point[seed.x-1][seed.y+1] = c;
queue.offer(new Point(seed.x-1,seed.y+1));
}
if(queue.size()>0) {
point[seed.x][seed.y] = c;
Point s = (Point) queue.poll();
point[s.x][s.y] = c;
seed = s;
}else {
return;
}
}while(true);
}
}
Demo.java
package com.lb.test;
import java.util.LinkedList;
/**
* 種子填充演算法
* @author lanbing
* @date 2018年9月17日
*
*/
public class Demo1 {
//矩陣的行列
public final static int ROW = 19;
public final static int COL = 19;
//生成三列分割點
public final static int[] COL1 = new int[] {4,8,12};
//生成三行分割點
public final static int[] ROW1 = new int[] {4,8,12};
//填充的字元
public final static String FILLCHAR = "#";
//生成的隨機點
public final static int SUM = 50;
public static void main(String[] args) {
String[][] point = new String[ROW][COL];
//初始化矩陣
for(int i=0;i<ROW;i++) {
for(int j=0;j<COL;j++) {
if(i==0){
point[i][j] = FILLCHAR;
}else if(i==ROW-1){
point[i][j] = FILLCHAR;
}else if(j==0){
point[i][j] = FILLCHAR;
}else if(j==COL-1){
point[i][j] = FILLCHAR;
}else {
point[i][j] = "*";
}
}
}
//顯示矩陣
ShowPoint(point);
System.out.println();
// //新增縱向分隔
// AddColPoint(point);
//
// ShowPoint(point);
// System.out.println();
//
// //新增橫向分隔
// AddRowPoint(point);
//
// ShowPoint(point);
// System.out.println();
//
//
// point[4][4] = "*";
//
//
// ShowPoint(point);
// System.out.println();
//
//
// //生成隨機點
// GetRandom(50,point);
// ShowPoint(point);
Point seed = new Point(3, 3);
Fill f = new Fill(point, FILLCHAR);
f.DemoFill8(seed);
ShowPoint(f.point);
}
/**
* 展示矩陣
* @param point
*/
public static void ShowPoint(String[][] point) {
for(int i=0;i<ROW;i++) {
for(int j=0;j<COL;j++) {
System.out.print(point[i][j]);
}
System.out.println();
}
}
/**
* 隨機生成干擾點
* @param n
* @return
*/
public static void GetRandom(int n,String[][] point){
LinkedList<Point> p = new LinkedList<Point>();
do {
if(p.size()>=n) {
break;
}else {
Point po = new Point((int)Math.floor(Math.random()*ROW),(int)Math.floor(Math.random()*COL));
if(!p.contains(po)) {
p.add(po);
}
}
}while(true);
for(int i=0;i<p.size();i++) {
point[p.get(i).x][p.get(i).y] = "#";
}
}
/**
* 三列分割點
* @return
*/
public static void AddColPoint(String[][] point) {
for(int i=0;i<ROW;i++) {
for(int j=0;j<COL;j++) {
for(int k=0;k<COL1.length;k++) {
if(j==COL1[k]) {
point[i][j] = FILLCHAR;
}
}
}
}
}
/**
* 三橫分割點
* @return
*/
public static void AddRowPoint(String[][] point) {
for(int i=0;i<ROW;i++) {
for(int j=0;j<COL;j++) {
for(int k=0;k<ROW1.length;k++) {
if(i==ROW1[k]) {
point[i][j] = FILLCHAR;
}
}
}
}
}
}
有不對的地方請多多指教!