AffineTransform setToRotation - 参数代表什么？

Question

I am currently trying to make som polygons rotate for my Asteroids game! :)

In order to do that, I'm using the AffineTransform setToRotation() method, however I am very confused about the meaning of the parameters. For setToRotation(a, b, c) I understand that b and c are the x and y coordinates of the point, the shape revolves around. a somehow makes the shape rotate, but it doesn't appear to be in degrees. So what else is it? And what to the other two setToRotation methods ( setToRotation(a, b) and setToRotation(a) ) do? I dont understand them AT ALL.

Thanks for every answer!

Answer 1

As in the documentation :

theta - the angle of rotation measured in radians

All of the trigonometric functions in java.lang.Math either accept or return radians.

You can convert from degrees to radians using Math.toRadians .

The other method overloads are also described in the documentation. Unless you can describe what about them you don't understand, there is no point in trying to explain them again, as that explanation could be in the same terms that you don't understand.

Answer 2

So what else is it?

It is in radians. You can see its documentation here . To convert from degrees to radians, just divide by 180 then times by π, so π radians is 180 degrees for examples. Or you can use Math.toRadians .

And what to the other two setToRotation methods (setToRotation(a, b) and setToRotation(a)) do?

Those are also very well documented. See this and this .

Basically, the one that takes one parameter is equivalent to calling setToRotation(a, b, c) but with b and c all equal to 0, and the one that takes 2 parameters is equivalent to calling setToRotation(a) with the inverse tangent of the quotient of the two parameters ( setToRotation(Math.atan2(a, b)) ).