Rotation Formula

[jerryD]

For calculating a new "x" point of rotation I found the formula:

x' = radius * cos(angle + -rotation) which converts to:

x' = radius cos angle cos rotation - radius sin angle sin rotation

Where does "radius sin angle sin rotation" come from?

Jerry D.

 

[Deleted member 4993]

For calculating a new "x" point of rotation I found the formula:

x' = radius * cos(angle + -rotation) which converts to:

x' = radius cos angle cos rotation - radius sin angle sin rotation

Where does "radius sin angle sin rotation" come from?

Jerry D.

Trig identity:

cos(Θ+Φ) = cos(Θ)*cos(Φ) - sin(Θ)*sin(Φ)