Drawing Lines
Go Up to Drawing Lines and Polylines
To draw a straight line on a canvas, use the LineTo method of the canvas.
LineTo draws a line from the current pen position to the point you specify and makes the endpoint of the line the current position. The canvas draws the line using its pen.
For example, the following method draws crossed diagonal lines across a form whenever the form is painted:
procedure TForm1.FormPaint(Sender: TObject);
begin
with Canvas do
begin
MoveTo(0, 0);
LineTo(ClientWidth, ClientHeight);
MoveTo(0, ClientHeight);
LineTo(ClientWidth, 0);
end;
end;
void __fastcall TForm1::FormPaint(TObject *Sender) {
Canvas->MoveTo(0,0);
Canvas->LineTo(ClientWidth, ClientHeight);
Canvas->MoveTo(0, ClientHeight);
Canvas->LineTo(ClientWidth, 0);
}