Изобразить вращающийся треугольник

uses crt,graphABC;
procedure Vrash(a:real;var x,y:integer;x0,y0,d:integer);
begin
x:=x0+round(d*cos(a));
y:=y0-round(d*sin(a));
end;
 
var gd,gm:integer;
    ch:char;
    x0,y0,d,ax,ay,bx,by,k:integer;
    aa,ab:real;
begin
gd:=0;
 
d:=150;
x0:=600 div 2;y0:=400 div 2;{
aa:=pi/3;ab:=2*pi/3;
ax:=x0+round(d*cos(aa));
ay:=y0-round(d*sin(aa));
bx:=x0+round(d*cos(ab));
by:=y0-round(d*sin(ab));
Setcolor(12);{?enoai}
line(x0,y0,ax,ay);
line(ax,ay,bx,by);
line(x0,y0,bx,by);
repeat
delay(100);
clearWindow;
Vrash(aa,ax,ay,x0,y0,d);
Vrash(ab,bx,by,x0,y0,d);
 
line(x0,y0,ax,ay);
line(ax,ay,bx,by);
line(x0,y0,bx,by);
aa:=aa+0.1;ab:=ab+0.1;
until keypressed;
readln
end.

uses graphABC,crt;
procedure Vrash(a:real;var x,y:integer;x0,y0,d:integer);
begin
x:=x0+round(d*cos(a));
y:=y0-round(d*sin(a));
end;
 
var ch:char;
    x0,y0,d,ax,ay,bx,by:integer;
    aa,ab:real;
begin
hidecursor;
d:=150;
x0:=windowwidth div 2;
y0:=windowheight div 2;
aa:=-pi/3;
ab:=4*pi/3;
lockdrawing;
repeat
clearWindow;
Vrash(aa,ax,ay,x0,y0,d);
Vrash(ab,bx,by,x0,y0,d);
line(x0,y0,ax,ay);
line(ax,ay,bx,by);
line(x0,y0,bx,by);
delay(100);
aa:=aa+0.1;
ab:=ab+0.1;
redraw;
until keypressed;
end.