update method
Advance one frame and return the new position.
Implementation
Point update() {
_pos = Point(
_pos.x + _vel.x * deltaTime,
_pos.y + _vel.y * deltaTime,
_pos.z + _vel.z * deltaTime,
);
_vel = Vector(
_vel.x + _acc.x * deltaTime,
_vel.y + _acc.y * deltaTime,
_vel.z + _acc.z * deltaTime,
);
return _pos;
}