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Could you explain me light and shadow concept
from RGB and math point of view.
I need to get three colors from one.
In analogy to existing COLOR_BTNFACE,COLOR_BTNHIGHLIGHT,COLOR_BTNSHADOW.
Given here COLOR_BTNFACE and COLOR_BTNHIGHLIGHT,COLOR_BTNSHADOW
should be produced.
How could I do it?

And one more question what is the way around if given color is too
dark to make shadow from it?
How would one bias it to get yet 2 additional colors for 3D effect?

I'm absolute beginner in color field, detailed explonations are wellcome.

I've drawn hundreds of 3D buttons in Paint. There are 1,2 and 3-line heights. I prefer 2-line ones.
You have this:

WWWWWWWB

WLLLLLDB

WLXXXXDB

WLXXXXDB

WLXXXXDB

WLXXXXDB

WDDDDDDB

BBBBBBBB

X is the color of the face {R1:G1:B1}
B is black {0:0:0}
W is white
L is "light" {R1*2 : G1*2 : B1*2}
D is "dark" {R1/2 : G1/2 : B1/2}

For a better picture, make a snapshot of a normal Win button, and you should know the simple formula I gave for "Dark" and "Light" above.

I've been making some slappy experiments
with 3d colored lines, testing different logic
for 3 color creation.
And noticed something that I yet can not fully comprehend.
For different colors diviation of light,shadow,normal is
different to achive shadow effect.
For example for pure green it's might be upto 5 times less then
for pure blue.
Here are some not optimized procs I briefly wrote to test color logic.
there is proc Pens3D that creates three pens.
If one would share simular 3D color procs, I'd appreaciate it.

If you understand it why not write in asm?
Or pseudo algo?
RGB -> HSL
HSL -> RGB
From first link it was clear from math equation
how to RGB - > HSL, though accurate implementation
of the equations seems too lengthy and slow.
I'm sure there should be shorter ways.

HueColour (float h, float m1, float m2)
What is h here? Hue?
What means hue here? RGB value?
(for example the same format in wich I specify color in CreatePen API?
if yes why is it float?)
I tried to compile it to lookup machine code - VC reported 3 errors

I found it by search :)
Anyway Rickey thaks for direction. (HSL and RGB)