Breaking It Down
In the turn function, why do we set the direction to values like Math.PI and -Math.PI/2?
Recall from Geometry, that angles, the amount of rotation, use radians instead of degrees. The avatar starts facing backward, toward the camera. So 0° of rotation is 0 radians of rotation, which means facing backward. And 180° is pi radians, which means facing forward into the screen. The following table is the complete list we’re using in the turn function.
Direction | Degrees | Radians | JavaScript |
|---|---|---|---|
Forward | 180° | pi | Math.PI |
Right | 90° | pi ÷ 2 | Math.PI/2 |
Left | -90° | -pi ÷ 2 | -Math.PI/2 |
Backward | 0° | 0 | 0 |
Why rotation.y?
So that explains the number that we use for the direction variable in the function turn, but why do we set rotation.y? Why not rotation.z or rotation.x
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