function ChangeRGBColor(color:TRGBTriple;R,G,B:integer):TRGBTriple;
begin

if  B+Color.rgbtBlue >255 then Color.rgbtBlue :=255 else
if  B+Color.rgbtBlue <0 then  Color.rgbtBlue :=0 else
inc(Color.rgbtBlue,B) ;


if  G+Color.rgbtGreen >255 then Color.rgbtGreen :=255 else
if  G+Color.rgbtGreen <0 then  Color.rgbtGreen :=0 else
inc(Color.rgbtGreen,G) ;

if  R+Color.rgbtRed >255 then Color.rgbtRed :=255 else
if  R+Color.rgbtRed <0 then  Color.rgbtRed :=0 else
inc(Color.rgbtRed,R) ;
Result:=Color;

end;