I am trying to make shapes for color mixing in additve mode and subtractive mode.
Additive mode is easy, as you have only to add color components of RGB color.
Subtractive mode is a bit complicated.
You need to convert RGB value to YMCK value, calculate mean Value of the components of YMCK value, and restore calculated YMCK value to RGB value.
Please enjoy color mixing, in the attatched Visio drawing.
Paint mixing is subtractive mixing.
Then I've added a drawing for Painting 2 Color Mixing.
You can change the quantity of colors by changing the width of the shapes.
Now you can add a little black to the much white color.
And it is very easy to expand to the paint mixing with 3 colors.
Color after penatrates through filters is different from paint mixing.
Color through 3 filters of Cyan, Magenta and Yellow is black.
Here is the trial drawing to examine the penetrating color.
This is a set of Paint Colors and the mixing pallet.
You can select color from legacy watercolor paint, copy color to the palet.
And you can blend new color from 3 colors.
You create some wonderful stuff, Yunichi!