Java学习 之 画图板 立方体

步骤

1、先画一个小立方体，三个面填充不一样的颜色
2、再由小立方体搭成一个3 * 3 * 3的立方体

3、以上图立方体为最小单位，递归画出更大的立方体

画小立方体

先填充三面颜色，用Polygon类，再画边线。

public class ShapeLFT {
 
  public void drawLFT(Graphics g,int x,int y){//画立方体的类
  g.setColor(new Color(100,255,100));
  g.fillRect(x, y, 30,30);//正面填充颜色
  
  //顶
  Polygon pon1=new Polygon();//四个顶点连成面
  pon1.addPoint(x, y);
  pon1.addPoint(x+15, y-15);
  pon1.addPoint(x+30+15, y-15);
  pon1.addPoint(x+30, y);
  
  g.setColor(new Color(188,255,166));
  g.fillPolygon(pon1);//填充
  
  //右侧面
  Polygon pon2=new Polygon();
  pon2.addPoint(x+30, y);
  pon2.addPoint(x+30+15, y-15);
  pon2.addPoint(x+30+15, y+30-15);
  pon2.addPoint(x+30, y+30);
  
  g.setColor(new Color(150,255,133));
  g.fillPolygon(pon2);
  
  //画边框
  g.setColor(new Color(60,255,20));
  //顶
  g.drawLine(x, y, x+15, y-15);//左上
  g.drawLine(x+30, y, x+30+15, y-15);//右上
  g.drawLine(x+15, y-15, x+30+15, y-15);//上
  //右侧面
  g.drawLine(x+30, y+30, x+30+15, y+30-15);//下
  g.drawLine(x+30+15, y-15, x+30+15, y+30-15);//右
  //正面
  g.drawLine(x, y, x+30, y);//
  g.drawLine(x+30, y, x+30, y+30);
  g.drawLine(x+30, y+30, x, y+30);
  g.drawLine(x, y+30, x, y);
 }

画3 *3 *3的立方体

根据一个小立方体的顶点坐标，推算其他小立方体的左上角的点的坐标，调用画小立方体的函数画出三层的立方体

public void drawShapeOne(Graphics g,int x,int y){
  //第一层
  drawLFT(g,x+15+15,y-15-15);//后左
  drawLFT(g,x+15+15+30,y-15-15);//后中
  drawLFT(g,x+15+15+30+30,y-15-15);//后右
  
  drawLFT(g,x+15,y-15);//中左
  drawLFT(g,x+30+30+15,y-15);//中右
  
  drawLFT(g,x,y);//前左
  drawLFT(g,x+30,y);//前中
  drawLFT(g,x+30+30,y);//前右
  
  //第二层
  drawLFT(g,x+15+15,y-15-15-30);//后左
  drawLFT(g,x+15+15+30+30,y-15-15-30);//后右
  drawLFT(g,x,y-30);//前左
  drawLFT(g,x+30+30,y-30);//前右
  
  //第三层
  drawLFT(g,x+15+15,y-15-15-60);//后左
  drawLFT(g,x+15+15+30,y-15-15-60);//后中
  drawLFT(g,x+15+15+30+30,y-15-15-60);//后右
  
  drawLFT(g,x+15,y-15-60);//中左
  drawLFT(g,x+30+30+15,y-15-60);//中右
  
  drawLFT(g,x,y-60);//前左
  drawLFT(g,x+30,y-60);//前中
  drawLFT(g,x+30+30,y-60);//前右
 }

递归画出更大的立方体

递归到最小的部分3 * 3 * 3立方体就画出来，否则就将大的分成小的来画
立方体左上角的坐标是画立方体传递的参数，要根据当前立方体的边长来算坐标

public void draw(Graphics g,int x,int y,int k){//k为立方体的边的长度，最小的立方体边长设为30
  if(k==90){//递归到3*3*3的立方体，调用函数画出
   drawShapeOne(g,x,y);
   return;
  }
  else{
   k=k/3;//先画小的立方体，小的边长是大的边长除以3
   //递归调用画出小的立方体
   //第一层
   draw(g,x+k,y-k,k);//后左
   draw(g,x+k+k,y-k,k);//后中
   draw(g,x+k+k*2,y-k,k);//后右
   
   draw(g,x+k/2,y-k/2,k);//中左
   draw(g,x+k+k+k/2,y-k/2,k);//中右
   
   draw(g,x,y,k);//前左
   draw(g,x+k,y,k);//前中
   draw(g,x+k*2,y,k);//前右
   
   //第二层
   draw(g,x+k,y-k-k,k);//后左
   draw(g,x+k+k*2,y-k-k,k);//后右
   draw(g,x,y-k,k);//前左
   draw(g,x+k*2,y-k,k);//前右
   
   //第三层
   draw(g,x+k,y-k-k*2,k);//后左
   draw(g,x+k+k,y-k-k*2,k);//后中
   draw(g,x+k+k*2,y-k-k*2,k);//后右
   
   draw(g,x+k/2,y-k/2-k*2,k);//中左
   draw(g,x+k*2+k/2,y-k/2-k*2,k);//中右
   
   draw(g,x,y-k*2,k);//前左
   draw(g,x+k,y-k*2,k);//前中
   draw(g,x+k*2,y-k*2,k);//前右
   
  }