Java:对象在路径上移动，忽略某些坐标。怎么修？

Question

我有一个从点 A 移动到随机点 B 的圆。当对象接近点 B 时，会选择一个新的随机目标位置。如果圆圈平行于 X 轴或 Y 轴移动，则对象会穿过沿途的所有像素并留下实线轨迹。但是如果圆沿对角线移动，它会跳过像素并轻微抖动，使动画不流畅并留下未绘制像素的痕迹。

我的算法是:

1. 计算X和Y距离
2. 检查圆是否在附近
3. 如果是，选择新的目的地
4. 如果 2. 为真，使用毕达哥拉斯定理求出实际距离
5. 如果2.为真，计算X和Y速度(坐标的变化)
6. 设置新坐标(不管2.是否为真)

代码如下:

  public void move ()//движение
  {
      //finds the X and Y distance to the destination
      int triangleX = nextLocationX - coorX;
      int triangleY = nextLocationY - coorY;
      //if too near the coordinates of the destination changes
      if (Math.abs(triangleX) <= Math.abs(speedX) || Math.abs(triangleY) <= Math.abs(speedY))//setting the new target
      {
          //setting the new destinatio
          int randInt;
          for (;;)//I don't want the the new destination to be that same spot
          {
              randInt= randGen.nextInt(appletX);
              if (randInt != nextLocationX)
              {
                  nextLocationX = randInt + radius;
                  break;
              }
          }
          for (;;)
          {
              randInt = randGen.nextInt(appletY);
              if (randInt != nextLocationY)
              {
                  nextLocationY = randInt + radius;
                  break;
              }
          }
          //calculating the change of the circle's X and Y coordinates
          triangleX = nextLocationX - coorX;
          triangleY = nextLocationY - coorY;
          speedX = ((double)(speed * triangleX) / (Math.sqrt (Math.pow(triangleX, 2) + Math.pow(triangleY, 2))));
          speedY = ((double)(speed * triangleY) / (Math.sqrt (Math.pow(triangleX, 2) + Math.pow(triangleY, 2))));
      }
      //the realCoor variables are from type double
      //they are the exact coordinates of the circle
      //If I only use integers, the circle almost
      //never reaches it's destination
      //unless the change of the coordinates gets calculated
      //after every time they change
      realCoorX = realCoorX + speedX;
      realCoorY = realCoorY + speedY;
      coorX = (int)Math.round(realCoorX);
      coorY = (int)Math.round(realCoorY);
  }

我怀疑问题出在坐标变化的计算上。

Answer 1

对我来说，这听起来像是一个别名问题。如果你画(!)一条不与坐标轴对齐的线，你会遇到同样的问题。如您所知，即对角线需要“半填充”像素才能看起来平滑。

您的解决方案是(取决于渲染技术)使用浮点位置计算。