Generating a square with rotating FOR-NEXT loop - why isn't it working?

Bilkins — Thu, 20 Nov 2025 07:44:31 GMT

Hi,

I'm making a 2D script where I define the side of a square, and then I want to use a FOR-NEXT loop to generate the rest of the square.

I've made two scripts that I think should work exactly the same, but they don't - can anytone illuminate me as to why?

First I made a manual script. This generates a perfect square as intended:

side = 1 LINE2 0, 0, side, 0 ! bottom edge ADD2 side, 0 ROT2 90 LINE2 0, 0, side, 0 ! right edge ADD2 side, 0 ROT2 90 LINE2 0, 0, side, 0 ! top edge ADD2 side, 0 ROT2 90 LINE2 0, 0, side, 0 ! left edge END

Then I try to make the same script as a FOR-NEXT loop:

side = 1 FOR i = 1 TO 4 ROT2 90*(i-1) LINE2 0, 0, side, 0 ADD2 side, 0 ! move to the endpoint for the next edge NEXT i END

This script only generates the bottom and right edge - why?

I would imagine that increasing i>4 would generate an overlapping loop, but the geometry just keeps getting more and more wonky - what is the logic I'm not getting?

EDIT: 20 seconds after posting I realised I just needed to change the rotation to a simple 90 degrees turn at the bottom of the transformation stack instead of a "fancy" 90*(i-1) at the start.
I don't see a button to delete this post, so I'm leaving it up to be shamed.

Solution:

FOR i = 1 TO 4 LINE2 0, 0, side, 0 ADD2 side, 0 ! move to the endpoint for the next edge ROT2 90 NEXT i

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Generating a square with rotating FOR-NEXT loop - why isn't it working?