Due to the fact that Terps will terraform the closest spot to them first, you can make circles of any size by simply placing a Terp at the origin of your circle and waiting for it to terraform as far out as you wish. You can speed up the process by stacking Terps in Edit Mode and can increase their range with the forge.
(Not really a)
Spoiler
Build a ton of Totems and set the Forge's range upgrade limit to -1. I also used 4 Terps as 4x cells are terraformed for each increase in size.
(http://i.imgflip.com/4ka2t.gif) (http://imgflip.com/i/4ka2t)
Change the terrain color, and it looks an awful lot like the creeper expanding...
Quote from: Kingo on October 11, 2013, 11:45:07 PM
Change the terrain color, and it looks an awful lot like the creeper expanding...
It will be a few minutes, and that might be because the creeper spreads in all directions at the same rate. (making a circle)
When Virgil needed a circular map, he wrote a CRPL script to create terrain based on the math for a circle. Afterwards, he destroyed the CRPL core and Mistet was born.
Quote from: Grauniad on October 11, 2013, 11:57:41 PM
When Virgil needed a circular map, he wrote a CRPL script to create terrain based on the math for a circle. Afterwards, he destroyed the CRPL core and Mistet was born.
That's definitely fancier than using a terp.