Реализовать движение фигур статическими методами

TTriangle = object (TLineSegment)
  private
    x3, y3: integer;
  public
    constructor Init;
    procedure Draw;
    procedure Erase;
    function getX3: integer;
    function getY3: integer;
    procedure setX3(newX: integer);
    procedure setY3(newY: integer);
  end;

TTriangle = object (TLineSegment)
  private
    x3, y3: integer;
  public
    constructor Init;
    procedure Draw;
    procedure Erase;
    procedure MoveBy(dx,dy: Integer);
  end;
 
procedure TTriangle.Draw;
begin
  SetColor(color);
  MoveTo(x3,y3); LineTo(x1,y1); LineTo(x2,y2); LineTo(x3,y3); 
end;
 
procedure TTriangle.Erase;
var
  OldColor: Word;
begin
  OldColor:=Color;
  Color:=GetBkColor;
  Draw;
  Color:=OldColor;
end;
 
procedure TTriangle.MoveBy(dx,dy: Integer);
begin
  Erase;
  Inc(x1,dx); Inc(x2,dx); Inc(x3,dx);
  Inc(y1,dy); Inc(y2,dy); Inc(y3,dy);
  Draw;
end;

type
  TShapes=(shPoint, shLine, shTriangle);
  PPoint=^TPoint;
  TPoint=object
    Shape: TShapes;
    constructor Init(AX,AY: Integer);
    ...
  end;
 
constructor TPoint.Init;
begin
  Shape:=shPoint;
  ...
end;
 
var
  s: array [1..9] of PPoint;
  i: Integer;
begin
  for i:=1 to 3 do s[i]:=New(PPoint,Init(...));
  for i:=4 to 6 do s[i]:=New(PLine,Init(...));
  for i:=7 to 9 do s[i]:=New(PTriangle,Init(...));
 
  for i:=1 to 9 do
    case s[i].Shape of
    shPoint:    s[i]^.Draw;
    shLine:     PLine(s[i])^.Draw;
    shTriangle: PTriangle(s[i])^.Draw;
    end;
...
end.

var
  a: array [1..6] of ^TPoint;
...
a[1] := new(TPoint, Init);
a[2] := new(TCircle, Init);

const
  shPoint=1;
  shLine=2;
  shTriangle=3;
type
  TPoint=object
    Shape: Integer;
...
constructor TPoint.Init;  
begin
  Shape:=shPoint;
...

a[1] := new(pPoint, Init);
  a[2] := new(pCircle, Init);
  a[3] := new(pEllipse, Init);
  a[4] := new(pLineSegment, Init);
  a[5] := new(pTriangle, Init);
  a[6] := new(pRectangle, Init);
  old[1] := new(pPoint, Init);
  old[2] := new(pCircle, Init);
  old[3] := new(pEllipse, Init);
  old[4] := new(pLineSegment, Init);
  old[5] := new(pTriangle, Init);
  old[6] := new(pRectangle, Init);
...
      2: begin
           cycle := true;
           while cycle do
           begin
             old[choice]^ := a[choice]^;
             cycle := a[choice]^.Move;
             old[choice]^.Erase;
             a[choice]^.Draw;
           end;
         end;

uses Graph, Crt;
 
type
  PShape=^TShape;
  TShape=object
  protected
    x, y: Integer;
    color: Word;
  public
    constructor Init(aX, aY: Integer; aColor: Word);
    destructor  Done; virtual;
    procedure Draw; virtual; abstract;
    procedure MoveBy(adx, ady: Integer);
    procedure DrawColor(aColor: Word);
    procedure Erase;
  end;
  
  PPoint=^TPoint;
  TPoint=object(TShape)
    constructor Init(aX, aY: Integer; aColor: Word);
    procedure Draw; virtual;
  end;
  
  PLine=^TLine;
  TLine=object(TShape)
  protected
    dx, dy: Integer;
  public
    constructor Init(aX1, aY1, aX2, aY2: Integer; aColor: Word);
    procedure Draw; virtual;
  end;
 
  PTriangle=^TTriangle;
  TTriangle=object(TShape)
  protected
    dx2, dy2, dx3, dy3: Integer;
  public
    constructor Init(aX1, aY1, aX2, aY2, aX3, aY3: Integer; aColor: Word);
    procedure Draw; virtual;
  end;
 
constructor TShape.Init(aX, aY: Integer; aColor: Word);
begin
  x:=aX; y:=aY; color:=aColor;
end;
 
destructor  TShape.Done;
begin end;
 
procedure TShape.MoveBy(adx, ady: Integer);
begin
  Erase;
  Inc(x,adx); Inc(y,ady);
  Draw;
end;
 
procedure TShape.DrawColor(aColor: Word);
var
  OldColor: Word;
begin
  OldColor:=color;
  color:=aColor;
  Draw;
  color:=OldColor;
end;
 
procedure TShape.Erase;
begin
  DrawColor(GetBkColor());
end;
 
constructor TPoint.Init(aX, aY: Integer; aColor: Word);
begin
  inherited Init(aX,aY,aColor);
end;
 
procedure TPoint.Draw;
begin
  PutPixel(x,y,color);
end;
 
constructor TLine.Init(aX1, aY1, aX2, aY2: Integer; aColor: Word);
begin
  inherited Init(aX1, aY1, aColor);
  dx:=aX2-aX1;
  dy:=aY2-aY1;
end;
 
procedure TLine.Draw;
begin
  SetColor(color);
  MoveTo(x,y); LineRel(dx,dy);
end;
 
constructor TTriangle.Init(aX1, aY1, aX2, aY2, aX3, aY3: Integer; aColor: Word);
begin
  inherited Init(aX1,aY1,aColor);
  dx2:=aX2-aX1; dy2:=aY2-aY1;
  dx3:=aX3-aX1; dy3:=aY2-aY1;
end;
 
procedure TTriangle.Draw;
begin
  SetColor(color);
  MoveTo(x,y); LineTo(x+dx2,y+dy2); LineTo(x+dx3,y+dy3); LineTo(x,y);
end;
 
var
  s: array [1..10] of PShape;
  i: Integer;
begin
  {...}
  for i:=Low(s) to High(s) do
    case Random(3) of
    0:
      s[i]:=New(PPoint,Init(
        Random(GetMaxX),Random(GetMaxY),
        Random(GetMaxColor)+1));
    1:
      s[i]:=New(PLine,Init(
        Random(GetMaxX),Random(GetMaxY),
        Random(GetMaxX),Random(GetMaxY),
        Random(GetMaxColor)+1));
    2:
      s[i]:=New(PTriangle,Init(
        Random(GetMaxX),Random(GetMaxY),
        Random(GetMaxX),Random(GetMaxY),
        Random(GetMaxX),Random(GetMaxY),
        Random(GetMaxColor)+1));
    end;
  for i:=Low(s) to High(s) do s[i]^.Draw;
  for i:=Low(s) to High(s) do s[i]^.MoveBy(10,0);
  for i:=Low(s) to High(s) do s[i]^.MoveBy(0,-10);
  for i:=Low(s) to High(s) do begin
    s[i]^.Erase;
    Dispose(s[i],Done);
  end;
  {...}
end.

var
  o1: TPoint;
  o2: TCircle;
  o3: TEllipse;
  o4: TLineSegment;
  o5: TTriangle;
  o6: TRectangle;
begin
...
  o1.Init; o1.Draw;
  o2.Init; o2.Draw;
  o3.Init; o3.Draw;
  o4.Init; o4.Draw;
  o5.Init; o5.Draw;
  o6.Init; o6.Draw;
...
  case choice of
  1: o1.Move;
  2: o2.Move;
  3: o3.Move;
  4: o4.Move;
  5: o5.Move;
  6: o6.Move;
  end;
...