unit unit1;
inte***ce
uses
windows, messages, sysutils, variants, classes, graphics, controls, forms,
dialogs, extctrls, stdctrls, buttons;
type
tfmmain = class(tform)
procedure formpaint(sender: tobject);
end;
varfmmain: tfmmain;
a: byte;
implementation
uses math;
procedure c(x,y:integer; acanvas:tcanvas);stdcall;
begin
inc(a,2);
acanvas.pen.width := 5;
if odd(a mod 31) then
acanvas.pen.color := clwhite
else
acanvas.pen.color := clblack;
acanvas.moveto(x,y);
acanvas.li***o(x,y);
end;
procedure tfmmain.formpaint(sender: tobject);
begin
linedda(0,20,width,20,@c,longint(canvas));
linedda(0,0,width,height,@c,longint(canvas));
end;
end.
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