从内向外绘制一个正方形的像素 - Java

Question

我想绘制一个像素的正方形，等待数组中有多少项。正方形表示数组量，所以小方块表示小数组，大方块表示大数组。我很难概念化我如何去做这件事？

编辑：我正在使用Java 2D。

螺旋从1开始，然后逆时针向正方形外侧（即2,3,4,5等）前进。每个正方形可以用正方形表示的数据量表示。

Answer 1

public class Test { 

    enum Direction { 
     Right, 
     Up, 
     Left, 
     Down 
    } 

    public static void main(String... args) throws IOException { 

     BufferedImage image = new BufferedImage(100, 100, BufferedImage.TYPE_INT_ARGB); 

     int rgb = Color.BLACK.getRGB(); 

     Point p = new Point(50, 50); 
     Direction d = Direction.Right; 
     int currentSegmentLength = 1; 


     for (int i = 0; i < 100; i += 2) { 

      paintSegment(image, rgb, p, d, currentSegmentLength); 
      d = nextSegmentDirection(d); 

      paintSegment(image, rgb, p, d, currentSegmentLength); 
      d = nextSegmentDirection(d); 

      currentSegmentLength++; 
     } 


     ImageIO.write(image, "png", new File("test.png")); 
    } 

    private static void paintSegment(BufferedImage image, int rgb, Point p, 
      Direction d, int currentSegmentLength) { 

     for (int s = 0; s < currentSegmentLength; s++) { 
      image.setRGB(p.x, p.y, rgb); 

      switch (d) { 
      case Right: p.x++; break; 
      case Up: p.y--; break; 
      case Left: p.x--; break; 
      case Down: p.y++; break; 
      } 
     } 
    } 

    private static Direction nextSegmentDirection(Direction d) { 
     switch (d) { 
     case Right: return Direction.Up; 
     case Up: return Direction.Left; 
     case Left: return Direction.Down; 
     case Down: return Direction.Right; 

     default: throw new RuntimeException("never here"); 
     } 
    } 
}