Program BresenhamLine;
Type ScreenType = Record
         Width:Word;
     end;

Var Screen:ScreenType;
    ScreenY:Array[0..199] of Word;

Procedure CalcScreenY(Width:Word);
Var I:Integer;
begin
     for I:=0 to 199 do ScreenY[I]:=I * Width;
end;

Procedure SetPixel(X, Y:Word; Color:Word);
begin
     Mem[$A000:Y shl 8 + Y shl 6 + X]:=Color;
end;

Procedure BresenLine(X1, Y1, X2, Y2:Word; Color:Byte);
Var DeltaX, DeltaY, Inc1, Inc2, D, X, Y:Integer;
begin
     DeltaX:=X2 - X1;
     DeltaY:=Y2 - Y1;
     D:=DeltaY shl 1 - DeltaX;
     Inc1:=DeltaY shl 1;
     Inc2:=(DeltaY - DeltaX) shl 2;
     X:=X1;
     Y:=Y1;
     SetPixel(X, Y, Color);
     While X < X2 do
     begin
          if D < X1 then
          begin
               Inc(D, Inc1);
               Inc(X);
          end
          else
          begin
               Inc(D, Inc2);
               Inc(X);
               Inc(Y);
          end;
          SetPixel(X, Y, Color);
     end;
end;

begin
     asm
        mov ax, 0013h
        int 10h
        push 320
        call CalcScreenY
     end;
     BresenLine(0, 0, 319, 199, 15);
     ReadLn;
     asm
        mov ax, 0003h
        int 10h
     end;
end.