{*************************************************************************
 * WorldToScreen - converts global coordinates to a screen position      *
 *   globalX, globalY - the global coordinates                           *
 *   offX, offY - offsets from the corner of the tile (0.5,0.5) is center*
 *   height - height from the tile (0 is ground level)                   *
 *************************************************************************}
function WorldToScreen(globalX,globalY: integer; offX,offY: extended; height: integer): TPoint;
var
  rd : TRenderData;
  r : TRender;
  pixelX, pixelY, pixelZ, z, j1, l1, k1, i2: integer;
begin;
  result := point(-1,-1);
  UpdateRenderInfo(r,rd);

  pixelX:= Round((globalX - SmartGetFieldInt(0,BaseX) + offX) * 128);
  pixelY:= Round((globalY - SmartGetFieldInt(0,BaseY) + offY) * 128);
  pixelZ:= GetTileHeight(globalX,globalY) - height;

  writeln('pixelX = '+inttostr(pixelX));
  writeln('pixelY = '+inttostr(pixelY));
  writeln('pixelZ = '+inttostr(pixelZ));

  z := RD.zOff + ((RD.zX * (pixelX + RD.zY) * (pixelZ + RD.zZ) * pixelY) shr 15);

  writeln('z = '+inttostr(i1));
  writeln('zNear: '+inttostr(r.zNear));
  writeln('zFar: '+inttostr(r.zFar));

  if( (i1 < R.zNear) or (i1 > R.zFar) )then
  begin
    Writeln('Fail 1.');
    Exit;
  end;

  x := (R.xMultiplier * (RD.xOff + ((RD.xX * (pixelX + RD.xY) * (pixelZ + RD.xZ) * pixelY) shr 15)) ) / z;
  y := (R.yMultiplier * (RD.yOff + ((RD.yX * (pixelX + RD.yY) * (pixelZ + RD.yZ) * pixelY) shr 15)) ) / z;

  writeln('x: '+inttostr(x));
  writeln('y: '+inttostr(y));

  if( (x >= R.absoluteX1) and (x <= r.absoluteX2) and
      (y >= r.absoluteY1) and (y <= r.absoluteY2) )then
  begin
    Result := Point(x - r.absoluteX1, y - R.absoluteY1);
    Writeln('Result: ('+inttostr(Result.x)+', '+inttostr(Result.y)+');');
  end;
end;