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 color dodge mode
 Description: This mode is some kind of inverted multiply mode (the multiplication is replaced by a division of the "inverse"). Formula: f(a,b) = a / (1 - b) Disadvantage: The formula can result in values greater than 1, so some truncation can occur. Code: if b = 255 then result := 255 else begin c := (a SHL 8) DIV (255-b); if c > 255 then result := 255 else result := c; end;
 inverse color dodge mode
 Description: I've never seen this mode anywhere, probably because it is the same than color dodge mode, but base color and blend color are swapped (diagram 2 equals "flipped multiply mode"). Formula: f(a,b) = b / (1 - a) Disadvantage: The formula can result in values greater than 1, so some truncation can occur. Code: if a = 255 then result := 255 else begin c := (b SHL 8) DIV (255-a); if c > 255 then result := 255 else result := c; end;
 soft dodge mode
Description:
This mode is a combination of color dodge and inverse color burn mode, but a lot smoother than both of them. The base image is darkened a bit, but very bright blend colors are "dodged" in. I chose this name, because my aim was to make the color dodge mode softer.

Formula:
 f(a,b) = ½a / (1 - b) (for a + b < 1) 1 - ½(1 - b) / a (else)