Question

I’m trying to make a very simple game. In it I have objects (Circles) that have an xDirection and a yDirection, both of which can range between -1 to 1.

I have another object that can be rotated by the user (Pointer) atop of the Circles. I’ve achieved this rotation by copying some code I found online that gave me the angle of the Pointer from the y-axis that runs through the center of the Circle. (This).

Now i’d like the “gameplay” to be a case of the user angling the pointer into the direction he wants the circle to move. If I have this angle, is there a way I can calculate xDirection and yDirection for the circle?

Really appreciate any help, I know I need to work on my math!
Oh and I’m technically working in javascript, but i’m thinking there’s a purely mathematical solution that could be implemented in many languages?

Answer 1

If I’m reading your problem correctly, this should work:

x = -sin(angle)
y = -cos(angle)