Mega Code Archive
How to highlight a bitmap
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Title: How to highlight a bitmap
procedure Highlight(aSource, ATarget: TBitmap; AColor: TColor);
//alters ASource to ATarget by making it appear as if
//looked through
//colored glass as given by AColor
//ASource, ATarget must have been created.
//Isn't as slow as it looks.
//Physics courtesy of a post by K.H. Brenner
var i, j: Integer;
s, t: pRGBTriple;
r, g, b: byte;
cl: TColor;
begin
cl := ColorToRGB(AColor);
r := GetRValue(cl);
g := GetGValue(cl);
b := GetBValue(cl);
aSource.PixelFormat := pf24bit;
ATarget.PixelFormat := pf24bit;
ATarget.Width := aSource.Width;
ATarget.Height := aSource.Height;
for i := 0 to aSource.Height - 1 do
begin
s := ASource.Scanline[i];
t := ATarget.Scanline[i];
for j := 0 to aSource.Width - 1 do
begin
t^.rgbtBlue := (b * s^.rgbtBlue) div 255;
t^.rgbtGreen := (g * s^.rgbtGreen) div 255;
t^.rgbtRed := (r * s^.rgbtRed) div 255;
inc(s);
inc(t);
end;
end;
end;
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