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procedure
TForm1.FormCreate(Sender: TObject);
{ Draw 1 pixcel
width line }
procedure DrawLine(X,Y,H,L:Integer;
Step:Real);
Var
R, C : Integer;
Begin
For R:=0
To H Do
Begin
{
Change fill color }
If
R<=L Then
Begin
C:=Round(R*Step);
{
Black -> Red }
Image1.Canvas.Pen.Color:=RGB(C,0,0)
End
Else
If R<=2*L Then
Begin
C:=Round((R-L)*Step);
{
Red -> Black }
Image1.Canvas.Pen.Color:=RGB(255-C,0,0)
End;
{
Fill area by drawing lines }
Image1.Canvas.MoveTo(X,Y+R);
Image1.Canvas.LineTo(X+1,Y+R);
End;
End;
Var
Angle, X, Y, H, H2, W, L : Integer;
Step : Real;
begin
{ Get form size
}
H:=Image1.Height;
W:=Image1.Width;
{ Fill image area
by form color }
Image1.Canvas.Brush.Color:=clBlack;
Image1.Canvas.Pen.Color:=clBlack;
Image1.Canvas.Rectangle(0,0,W,H);
{ Set fill size
}
H2:=150;
L:=H2 Div 2;
{ Set fill step
size }
Step:=255/L;
Angle:=0;
For X:=1 to W Do
Begin
Y:=Round(100*Sin(Angle*(Pi/180)));
DrawLine(X,(H
Div 3)-Y,H2,L,Step);
Inc(Angle);
If Angle>360
Then Angle:=0;
End;
end;
