I would start with an integer, that stores the size of the current side you are drawing, and also have another variable that stores on which side of the square you are on. I don't want to be giving you too much help though, as this is most definitely homework.

andrewgies17

are you firmiliar with the line() function? how about for() ? what exactly is your experience with processing.

andrewgies17

so I wouldn't try to do the spiral all at once, but do each size individually, such as write all of the lines in the top part of the spiral like this:

I wrote this code:

int xpos = 250;
int ypos = 250;
 
size(640, 600);

for (int i = 5; i < 250; i += 10) {
  line(xpos, ypos, xpos + i, ypos);
  line(xpos + i, ypos, xpos + i, ypos - i);
  line(xpos + i, ypos - i, xpos - (i + 5), ypos - i);
  line(xpos - (i + 5), ypos - i, xpos - (i + 5), ypos + (i + 5));
  }

but it still is only drawing three sides when it should be drawing four.

This is a good start, but look at some lengths: they don't go the full side of the square.
And why use a half step as offset? It breaks the continuity.
I fixed the short line, used a constant as increment (allowing to ease experimentations) and changed the color as a debugging help (which line go where):

1. int xpos = 250;
2. int ypos = 250;
3. int incr = 10;
4.  
5. size(640, 600);
6.  
7. for (int i = 5; i < 245; i += incr) {
8.   stroke(#FF0000);
9.   line(xpos - i, ypos + i, xpos + i, ypos + i);
10.   stroke(#FFFF00);
11.   line(xpos + i, ypos + i, xpos + i, ypos - i);
12.   stroke(#00FF00);
13.   line(xpos + i, ypos - i, xpos - (i + incr), ypos - i);
14.   stroke(#00FFFF);
15.   line(xpos - (i + incr), ypos - i, xpos - (i + incr), ypos + (i + incr));
16. }