function initRotations () {
var rotation = this.options.rotation;
this.rotations = {
prev : FM.aboutOrigin([0,0,-this.options.radius], FM.rotateX( rotation )),
curr : FM.aboutOrigin([0,0,-this.options.radius], FM.rotateX( 0 )),
next : FM.aboutOrigin([0,0,-this.options.radius], FM.rotateX( -rotation ))
}
}
function _sphereAnglesToShape(sphereAngles, r) {
var result = [];
for(var i = 0; i < sphereAngles.length; i++) {
result.push(Matrix.moveThen([0, 0, r], Matrix.multiply(Matrix.rotateX(sphereAngles[i][0]), Matrix.rotateY(sphereAngles[i][1]))));
}
return result;
};