绘制矩形和网格

Question

如果有人能帮助我，我将非常感激。

我的程序有两个类。一个绘制矩形和网格，另一个是查看器。问题是，当我试图改变贪婪+矩形的位置时，即更新Viewer类中的X和Y常量，比例会发生变化。只有当X=0和Y=0时，网格才适合。

我使用相同的坐标数组来绘制网格和矩形，但不知何故比例是错误的，这让我感到惊讶。

谢谢。我代码:

import java.applet.Applet;
import java.awt.Graphics;
import java.awt.Color;
import java.awt.Graphics2D;
import java.awt.geom.Line2D;
import java.awt.geom.Rectangle2D;
import java.math.BigDecimal;

public class Viewer extends Applet {
  public static final double R_WDTH = 12;//rectangle width
  public static final double X = 10;//the grid fits in only when X=Y=0
  public static final double Y = 10;
  public static final int ROWS = 25;
  public static final int COLUMNS = 12;
  RectangleAndGrid cup = new RectangleAndGrid(X, Y, R_WDTH, ROWS, COLUMNS);
  public void paint(Graphics g) {
    cup.draw((Graphics2D)g);
  }
}

public class RectangleAndGrid {
  private double x, y, blockWidth;
  private int rows, columns;
  private double coordX[][], coordY[][];
  private Rectangle2D.Double cupSpace;
  public RectangleAndGrid(double cX, double cY, double givenBlockWidth, int r, int c){
    x = cX;
    y = cY;
    blockWidth = givenBlockWidth;
    rows = r;
    columns = c;
    BigDecimal currX = BigDecimal.valueOf(x);
    BigDecimal currY = BigDecimal.valueOf(y);
    coordX = new double[rows + 1][columns + 1];
    coordY = new double[rows + 1][columns + 1];
    for(int i = 0; i <= rows; i++){
      for(int j = 0; j <= columns; j++){
        coordX[i][j] = currX.doubleValue();
        coordY[i][j] = currY.doubleValue();
        currX = currX.add(BigDecimal.valueOf(blockWidth));
      }
      currX = BigDecimal.valueOf(x);
      currY = currY.add(BigDecimal.valueOf(blockWidth));
    }
    cupSpace = new Rectangle2D.Double(coordX[0][0], coordY[0][0], coordX[rows][columns], coordY[rows][columns]);
  }
  public void draw(Graphics2D g2d){
    g2d.setColor(Color.CYAN);
    g2d.fill(cupSpace);
    g2d.setColor(Color.BLACK);
    g2d.draw(cupSpace);
    Line2D.Double line = new Line2D.Double();
    for(int i = 0; i <= rows; i++){
      line.setLine(coordX[i][0], coordY[i][0], coordX[i][columns], coordY[i][columns]);
      g2d.draw(line);
    }
    for(int i = 0; i <= columns; i++){
      line.setLine(coordX[0][i], coordY[0][i], coordX[rows][i], coordY[rows][i]);
      g2d.draw(line);
    }
  }
}

Answer 1

首先，你的方法有点奇怪，不完全是坏的，只是有点奇怪- IMHO

Rectangle2D有四个参数:x、y、width和height。在你的代码中，你正在传递网格的顶部，左侧和右下角，这意味着，你的"杯子"的宽度/高度实际上比x像素更宽(y像素更高)

基本上，你需要从右下角的坐标中减去x/y的偏移量…

cupSpace = new Rectangle2D.Double(coordX[0][0], coordY[0][0], coordX[rows][columns] - coordX[0][0], coordY[rows][columns] - coordY[0][0]);