There are two modes of diffusion control, but be careful when changing.
From Ciel to Lune
Lune gradually changes from the current color to the desired color. In other words, in order to change modes smoothly, the hue of Cile must be the starting color of Lune. Ignore the saturation and lightness, and in such a case, add another step in between to change it smoothly.
From Lune to Ciel
Since the hue of Lune is moving, it is difficult to make a perfect transition. But if there is a MOTOR effect, it can be covered to some extent. Specially, the current display color will be moved to the initial value of MOTOR. MOTOR is effective only at CIEL, so only in this direction.
Fixed the core routine of diffusion control. The control method was not changed, only the algorithm was modified, but it became simple. As always, when it goes well, it always gets simpler.