TeCanvas.ApplyDark

ApplyDark function

function ApplyDark(Color: TColor; HowMuch: Byte): TColor;

Unit
TeCanvas

Description
The ApplyDark function converts the Color parameter to a darker color.
The HowMuch parameter indicates the quantity of dark increment.

It is used by TBarSeries and TPieSeries to calculate the right color to draw Bar sides and TPieSeries 3D zones.
The TeCanvas unit must be in your uses clause.

This is the ApplyDark source code:

Function ApplyDark(Color:TColor; HowMuch:Byte):TColor;
Var r,g,b:Byte;
begin
Color:=ColorToRGB(Color);

r:=GetRValue(Color);
g:=GetGValue(Color);
b:=GetBValue(Color);

if r>HowMuch then r:=r-HowMuch else r:=0;
if g>HowMuch then g:=g-HowMuch else g:=0;
if b>HowMuch then b:=b-HowMuch else b:=0;

result:=RGB(r,g,b);
end;

Example:

Series1.Color := ApplyDark( Series1.Color, 128 );