Some error

[Mefistosss]

intro.js
var M_PI = Math.PI;
var M_PI_2 = M_PI / 2;
var M_2_PI = 2 * M_PI;
...
var SCREEN_ROTATION_0 = 0,
SCREEN_ROTATION_90 = M_PI_2,
SCREEN_ROTATION_180 = M_PI,
SCREEN_ROTATION_270 = M_2_PI / 3,
SCREEN_ROTATION_MINUS_90 = - M_PI_2;

SCREEN_ROTATION_270 = M_2_PI / 3, // Error -> M_2_PI - M_PI_2

360 / 3 = 120 (not 270)

[pjbaron]

"M_2_PI / 3"
720 / 3 = 240 (not 120 or 270) ;)

[Mefistosss]

Yes and it is error.
Solution is M_2_PI - M_PI_2

360 / 3 = 120 (not 270) - Sorry, my bad, you are right