Hi I was wondering what sort of detection algorithm you use for radar/sonar/IR/VIS. In particular is it deterministic? (in the sense that once you can get detected you will). Does it take into account time on station(i.e. a sub/missile is within detection range but will only be detected after x min of observation)?
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The detection algorithms are deterministic, but not time based (the sensor sweep is the most CPU intensive code in the entire game, so we had to cut some corners there). Once all the variables add up, you get a detection, and at a certain signal strength threshold (or if several sensors independently see a target) you get it fixed and/or identified.
Yes I was walking home from work and thinking about how I wound do it (solving the radar equation for all possibilities) and quickly realised that it might be way to CPU expensive. It seems as though you have made a good compromise I'm looking forward to test it! 
My only issue with not taking into account time on station(TOS) time is for detecting submarines and missiles.
For subs no TOS mean that I can so a sprint and drift tactic drifting for just 1s and then sprinting again, which might be abused by players for small scenarios (1-2 subs, 1-2 escorts).
For missiles it means that they are much more lethal than they might be easier to shoot down than in real life. If you detect all missiles at the radar horizon you can engage them much earlier than if you had to wait 1-2s to get a detection(which is probably needed to distinguish a missile from sea clutter). And further in real life you might detect 90% of the missles at long range but for some reason(signal processing algorithm, operator error, sea clutter) the last 10% might only detected at 2/3 range or even less.
I guess the last issue can be fixed by reducing the radar cross sections of the missles in the game and operator error can be simulated by nerfing the hit probability of SAMs. But the issue for sub hunting I'm not sure of..
My only issue with not taking into account time on station(TOS) time is for detecting submarines and missiles.
For subs no TOS mean that I can so a sprint and drift tactic drifting for just 1s and then sprinting again, which might be abused by players for small scenarios (1-2 subs, 1-2 escorts).
For missiles it means that they are much more lethal than they might be easier to shoot down than in real life. If you detect all missiles at the radar horizon you can engage them much earlier than if you had to wait 1-2s to get a detection(which is probably needed to distinguish a missile from sea clutter). And further in real life you might detect 90% of the missles at long range but for some reason(signal processing algorithm, operator error, sea clutter) the last 10% might only detected at 2/3 range or even less.
I guess the last issue can be fixed by reducing the radar cross sections of the missles in the game and operator error can be simulated by nerfing the hit probability of SAMs. But the issue for sub hunting I'm not sure of..
Very good points. We have been thinking much the same way, and tried to fix it. For example, we make sure that when a unit increases engine power, the sound will persist long enough to be picked up, even if you immediately slow down again.
Good, I have to say that it seems as though you guys are running a very professional operation. You seem to have very clear goals you are open with the capabilities and limitation of the game. It seems as though this will be a very good game indeed!
Speaking of Sonar and Sprint-Drift patterns:
Since most sonar contacts are passive, how do you plan to include Target-motion-analysis? Since a passive contact only gives you a bearing, and you would need range and speed/course as well to set up a firing solution.
Since most sonar contacts are passive, how do you plan to include Target-motion-analysis? Since a passive contact only gives you a bearing, and you would need range and speed/course as well to set up a firing solution.
Yes, that is a challenge. Since lightweight torpedoes have their own active sonars and can track targets, you can fire on a passively detected non-fixed target (where you have limited information). From my experience, you typically miss when you do so
We have not completely finalized the sonar system yet; we'll probably give you better information when a detection is old. This will probably not be entirely satisfactory for sub enthusiasts, but year, we have to cut some corners to simulate the rest of the world, too.
We have not completely finalized the sonar system yet; we'll probably give you better information when a detection is old. This will probably not be entirely satisfactory for sub enthusiasts, but year, we have to cut some corners to simulate the rest of the world, too.
How about background noise(i.e detection range) as a function of sea state, and or ocean depth?
Apparently active sonar is better in shallow water and bad weather(for shallow depths) since background SNR is given by background noise rather than attenuation (passive attenuates as distance^2 and active as distance^4)
(I think I read somewhere that you algorithm was based on a 1d angular resolution this would scale linearly with the distance so technically you will end up with a wrong difference in detection ranges for small/large cross-sections, but then who cares... as long as it plays well).
Sorry for being such simulation nerd...
Apparently active sonar is better in shallow water and bad weather(for shallow depths) since background SNR is given by background noise rather than attenuation (passive attenuates as distance^2 and active as distance^4)
(I think I read somewhere that you algorithm was based on a 1d angular resolution this would scale linearly with the distance so technically you will end up with a wrong difference in detection ranges for small/large cross-sections, but then who cares... as long as it plays well).
Sorry for being such simulation nerd...
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The more simulation nerds, the better!Sorry for being such simulation nerd...
We got that covered.
We do simulate a penalty for passive in shallow water and it is near useless near the surface in bad weather.
2d, but yes, I am aware of that and decided not to fiddle with it
We love simulation nerds, even if we know we can't 100% satisfy everybody!Sorry for being such simulation nerd...
ok sounds good!
I guess in the end any change in these algorithms require allot of rebalancing so best not to fiddle with it.
I guess in the end any change in these algorithms require allot of rebalancing so best not to fiddle with it.
Are the detection algorithm etc... hard wired within the core code, or are we able to make small changes to them, by making mods?
That's one of the things you can't change with a mod (without reverse-engineering the game). The parameters, however, are open.
I was wondering what about radar "sprint-and drift" tactics? Will I be able to turn my radar on for a split second to get a fix on the target, and then turn it off again? I now to a certain degree intermittent radar is used, but as with sonar signal processing and operator delays forces you to have the radar on for at least some time in real life.
You will need to have the radar on for some seconds to get a detection, yes. So quick on/off on radar (or sonar) is unlikely to work very well. Having it on for a few seconds, and then turning it off, might work in some circumstances.
Sorry if this has been covered already, but will passive contacts where range is indefinite like passive sonar, radar intercept, etc render a Line of Bearing onscreen?
Yes, that is, both bearing and range will be uncertain, and you get an on-map indicator of the sector the target may be inside.
What kind of passive detection penalties are assessed to units sonar performance based on the unit's class. I.E. a DDG or CG should not have the same passive detection range of an ASW centric unit like an FFG or Covette (Based on self noise). I'm speaking on the surface unit's passive detection of submarines. And what kind of penalties are assessed to units passive detection abilities based on the speed they are travelling, for example a unit travelling at over XX kts has almost zero chance of passively detecting a submarine (until it's too late) unless it is via stationary sensors (Sonobuoys, helo dipping). Plus adding more ships into it's area and the penalty should increase.