Trigonometry is used to precisely calculate the swash and tail helicopter mechanics.
The length of each swashplate arm can be adjusted, even such that the aileron (left & right) arms are different lengths to each other. By adjusting the arms accordingly it’s possible to produce 120, 140, etc, degree swashplates.
The “Crazy Swash Animation” video shows how the swash twists the blades as the heli body (swash bottom) and main blades (swash top) rotate relative to each other.
Ray projection is used which allows the transmitter gimbals and switches, and the control panel sliders, to be controlled by the mouse. This is useful because both the Tx and CP can be moved/zoomed and rotated within 3D space, which requires ray projection to act as the collision detection of the mouse pointer intersecting the controls.