Soft Dodge

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--if a + b < 256 then begin
--  if b = 255 then
--    result := 255
--  else begin
--    c := (a SHL 7) DIV (255-b);
--    if c > 255 then result := 255 else result := c;
--  end;
--end
--else begin
--  // a cannot be zero here
--  c := 255 - (((255-b) SHL 7) DIV a);
--  if c < 0 then result := 0 else result := c;
--end;
-- ******* soft dodge mode *************
on softDodgeBlendMode (image1, image2)
  theWidth = image1.width - 1
  theHeight = image1.height - 1
  theImage = image(theWidth + 1, theHeight + 1, 32)
  theMultiplier = 127.0
  repeat with x = 0 to theWidth
    repeat with y = 0 to theHeight
      theColour1 = image1.getPixel(point(x,y))
      theColour2 = image2.getPixel(point(x,y))
      theNewColour = color(0,0,0)
      if theColour1.red + theColour2.red < 256 then
        if theColour2.red = 255 then
          theNewColour.red = 255
        else
          theNewColour.red = min ((theColour1.red * theMultiplier) / float(255 - theColour2.red), 255)
        end if
      else
        -- cannot be zero here
        theNewColour.red = max(255 - (((255 - theColour2.red) * theMultiplier) / float(theCOlour1.red)), 0)
      end if
 
      if theColour1.green + theColour2.green < 256 then
        if theColour2.green = 255 then
          theNewColour.green = 255
        else
          theNewColour.green = min ((theColour1.green * theMultiplier) / float(255 - theColour2.green), 255)
        end if
      else
        -- cannot be zero here
        theNewColour.green = max(255 - (((255 - theColour2.green) * theMultiplier) / float(theCOlour1.green)), 0)
      end if
 
      if theColour1.blue + theColour2.blue < 256 then
        if theColour2.blue = 255 then
          theNewColour.blue = 255
        else
          theNewColour.blue = min ((theColour1.blue * theMultiplier) / float(255 - theColour2.blue), 255)
        end if
      else
        -- cannot be zero here
        theNewColour.blue = max(255 - (((255 - theColour2.blue) * theMultiplier) / float(theCOlour1.blue)), 0)
      end if
 
      theImage.setPixel(point(x, y), theNewColour)
 
    end repeat
  end repeat
  return theImage
end