Colorful Transparency Algorithm (Windows)

Dear font technology enthusiasts,

I let Windows draw a few glyphs with transparent background

 SetBkMode(glyph_hdc, TRANSPARENT);

 and to my astonishment, I saw this:



I think it's absolutely gorgeous and it looks intentional to me since the warm values are always on the right.

1) If it indeed is intentional, is the purpose to improve readability? What specifically does the coloring do to the eye?
Can someone elaborate or give some links?

2) I was about to store glyph bitmaps in a single channel and then color the glyphs inside a shader. This discovery makes me wonder how I could use these RGB values inside a shader to produce different colors.

Thank you