Треугольник стирает фон

uses crt,graph;
var gd,gm,a,ye,xe,col,xs,ys:integer;
procedure Treug(x,y,c,a:integer);
var x1,y1,x2,y2,x3,y3:integer;
begin
x1:=x;
y1:=y-a;
x2:=x-round(a*cos(pi/6));
y2:=y+round(a*sin(pi/6));
x3:=x+round(a*cos(pi/6));
y3:=y2;
setcolor(c);
setfillstyle(1,c);
line(x1,y1,x2,y2);
line(x1,y1,x3,y3);
line(x3,y3,x2,y2);
floodfill(x,y,c);
end;
procedure Move;
var x,y,x1,y1:integer;
c1,c2:byte;
k:char;
move:boolean;
begin
x:=340; y:=240;
c1:=12; c2:=0;
move:=true;
repeat
if keypressed then
begin
k:=readkey;
if k=#0 then k:=readkey;
case k of
#80:begin
y1:=y;
x1:=x;
if y<getmaxY-30 then y:=y+5;
move:=true;
end;
#72:begin
y1:=y;
x1:=x;
if y>41 then y:=y-5;
move:=true;
end;
#77:begin
y1:=y;
x1:=x;
if x<getmaxX-40 then x:=x+5;
move:=true;
end;
#75:begin
y1:=y;
x1:=x;
if x>40 then x:=x-5;
move:=true;
end;
end;
end;
if move then
begin
setlinestyle(0,0,3);
Treug(x1,y1,x2,a);
Treug(x,y,c1,a);
move:=false;
end;
until k=#27;
end;
begin
repeat
textcolor(white);
write('storona a= ');
readln(a);
until (a>=1)and(a<=150);
gd:=detect;
initgraph(gd,gm,' ');
while ye<=480 do
begin
col:=random(16);
if (col=0) or (col=1) then
begin
while (col=0) or (col=1) do
begin
col:=random(16);
end;
end;
setfillstyle(solidfill,col);
fillellipse(xs,ys,3,3);
xs:=xs+8;
xe:=xe+8;
end;
xs:=0;
xe:=3;
ys:=ys+8;
ye:=ye+8;
end;
Move;
closegraph;
end.

uses crt,graph;
var 
gd,gm,a,ye,xe,col,xs,ys:integer;
prov:byte;
procedure Treug(x,y,c,a:integer);
var x1,y1,x2,y2,x3,y3:integer;
begin
x1:=x;
y1:=y-a;
x2:=x-round(a*cos(pi/6));
y2:=y+round(a*sin(pi/6));
x3:=x+round(a*cos(pi/6));
y3:=y2;
setcolor(c);
setfillstyle(1,c);
line(x1,y1,x2,y2);
line(x1,y1,x3,y3);
line(x3,y3,x2,y2);
floodfill(x,y,c);
end;
procedure Move;
var x,y,x1,y1:integer;
c1,c2:byte;
k:char;
move:boolean;
begin
x:=340; y:=240;
c1:=12; c2:=0;
move:=true;
repeat
if keypressed then
begin
k:=readkey;
if k=#0 then k:=readkey;
case k of
#80:begin
y1:=y;
x1:=x;
if y<getmaxY-30 then y:=y+5;
move:=true;
end;
#72:begin
y1:=y;
x1:=x;
if y>41 then y:=y-5;
move:=true;
end;
#77:begin
y1:=y;
x1:=x;
if x<getmaxX-40 then x:=x+5;
move:=true;
end;
#75:begin
y1:=y;
x1:=x;
if x>40 then x:=x-5;
move:=true;
end;
end;
end;
if move then 
begin
setlinestyle(0,0,3);
Treug(x1,y1,x2,a);
Treug(x,y,c1,a);
move:=false;
end;
until k=#27;
end;
begin
repeat
textcolor(white);
write('storona a= ');
{$I-}
readln(a);
{$I+}
prov:IOResult;
if (prov<>0) or (a<=0) then
if (a<400) then
wrtiteln('Oshibka!!!')
else
until (prov=0) and (a>=1);
gd:=detect;
initgraph(gd,gm,' ');
while ye<=480 do
begin
col:=random(16);
if (col=0) or (col=1) then
begin
while (col=0) or (col=1) do
begin
col:=random(16);
end;
end;
setfillstyle(solidfill,col);
fillellipse(xs,ys,3,3);
xs:=xs+8;
xe:=xe+8;
end;
xs:=0;
xe:=3;
ys:=ys+8;
ye:=ye+8;
end;
Move;
closegraph;
end.

size:=imagesize(x1,y1,x2,y2);
getmem(p,size);
getimage(x1,y1,x2,y2,p^);
{...}
{рисуем фигуру}
{...}
delay(10);
putimage(x1,y1,p^,copyput);
freemem(p,size);