TZigZagEffect komponens

    w:=Width / FGridSizeX;
    h:=Height / FGridSizeY;

    yp:=(FGridSizeX*FGridSizeY - FStep) div FGridSizeX;
    xp:=(FGridSizeX*FGridSizeY - FStep) mod FGridSizeX;

    if (yp mod 2)=0 then x:=Round(xp*w) else x:=Round((FGridSizeX-xp-1)*w);
    y:=Round(yp*h);

    CopyImg(x, y, Trunc(w)+1, Trunc(h)+1);
  end;
end;