Getting point on a rectangle border

Question

To get points which lie on the border of a rectangle, I use 4 for loops. At first I thought about creating Rectangle and using PathItterator, but it confused me very much. Is there a better way than mine?

int r = 5;
int x = 0;
int y = 0;
int length = r * 2 + 1;
for (int i = 0; i < length; i++) {
    System.out.print(String.format("(%d,%d) ", x - r + i, y - r));
}
System.out.println();
for (int i = 0; i < length; i++) {
    System.out.print(String.format("(%d,%d) ", x - r + i, y + r));
}        System.out.println();

for (int i = 0; i < length; i++) {
    System.out.print(String.format("(%d,%d) ", x - r , y - r+i));
}        System.out.println();

for (int i = 0; i < length; i++) {
    System.out.print(String.format("(%d,%d) ", x + r , y - r+i));
}
System.out.println();

Answer 1

Most rectangles have a length and a width. I’ve never heard of a rectangle with a radius, but it would be known as a square.

More constructively:

System.out.print(String.format("(%d,%d) ", x - r + i, y - r));

Could be written as:

System.out.format("(%d,%d) ", x - r + i, y - r);

Answer 2

I hope you realize these things:

1. You are using r as the offset of the top-left from the origin.
2. You are using same length for width and height - so square
3. Length should be 2*r rather than 2r (guessing you made it +1 to make the loop work)
4. Your i should go from 0 to <=length. It should be inclusive range as you want to include both borders.

In other words, length = 2r. And for loop goes from i=0 to i<=length.

What do I mean by offset? The top-left corner will always be offset by (-r,-r) relative to the axes origin. As the length changes, only the bottom right corner will keep moving.

For example, if length is changed to length = 4r, then top-left corner will remain at (-r,-r) and bottom-right corner will move to (3r, 3r).

Here (+) represents the origin, and it is not at the center of the bigger square.

  ********************
  *                  *
  *                  *
  *                  *
  *                  *
  *    +             *
  *                  *
  *                  *
  *                  *
  ********************

You can better keep r=0, or remove the variable r completely, and just use length = 10. Then your square will start at (0,0) and go to (l, l).

If you want it to be a rectangle, you can use width and height instead of the common length.