there are plenty, but again, those are pretty basic, and most will just give you a seen/not seen scenario.
However, this one allows you setup obstructions, so you can get much closer to real-life (sorry, web-based):
there are plenty, but again, those are pretty basic, and most will just give you a seen/not seen scenario.
However, this one allows you setup obstructions, so you can get much closer to real-life (sorry, web-based):