You are turning too much each frame. I'd try "turn(4);", which will produce something more like a circle. The less degrees you turn each frame, the smoother the circle. Conversely, the sharper you turn, the less like a circle it will be. If you turn 15 degrees each frame, you'll make a (360/15=24) 24-sided shape. But 4 degrees will be a (360/4=90) 90-sided shape, which is getting indistinguishable from a circle. A few other things: - You don't need the "if (this != null)" check. "this" can never be null in Java (unlike C++) - You've got two semi-colons after move.

I changed move(2) to move(1). The Crocodile still turns. But the way, it walks is an octagon?

Well... That is cause. the standard getX() and getY() methods return an integer and the method setLocation expects two integer. Now, when you will move 1 pixel, the computer computer calculates the next Location from xour location with getX() and getY(), which are both integers... For example x=10 and y=10. And your rotation is for e.g something between 60 and 70.... Now the computer calculates for x =10.666...and for y 10.333... but this two numbers are decimal numbers... and he will round them to integers... so he has for x=11 and for y=10... so you next location will be x=11 and y=10 and when he calculates the next time, he takes 11 and 10 as starting prarameter... So if you want a perfect circle, you have to write a code, that is using double numbers, or to get a better circle use a higher number (e.g. 4 or 5)

Ah yes, Busch2207 has a good answer. Moving 1 pixel, you can only move at 0 degrees, 90 degrees or 45 degrees, but nothing inbetween. For such slow-moving objects, you need to keep track of the positions as floating-point. The Greenfoot 2.2.0 beta (see other forum thread), which will be finalised in the next week or two, has an Import Class mechanism where you can import a SmoothMover class. You can use that as a parent class, and it will handle all the sub-pixel precision, which would solve your problem when moving at slow speeds.

Ah ok! First I was a bit confused, but now I understand it! Thank you busch and nccb

Hey USBest! If you still want to let your crocodile move in a perfect circle, check out this scenario from SPower: http://www.greenfoot.org/scenarios/4873