[RESOLVED] Spoiler variable not transmitted in MP (v2 and v3)

Any issues, problems or troubleshooting topics related to the Prepar3D client application's multiplayer mode
MiG21bis
Posts: 17
Joined: Wed Apr 03, 2013 7:22 pm

[RESOLVED] Spoiler variable not transmitted in MP (v2 and v3)

Post by MiG21bis »

We do quite a bit of multiplayer work in v2 and now v3, and noticed that the spoiler (speed brake for us) variable is apparently not transmitted? Are we set up incorrectly, or did P3D actually reduce functionality in this respect? I'd expect LM to continually expand the usable variables, not to restrict them and reduce realism.

For military multi-ship ops, being able to call and see each others' "boards" is important.
FSMP
Posts: 678
Joined: Sat Sep 25, 2010 9:38 am

Re: Spoiler variable not transmitted in MP (v2 and v3)

Post by FSMP »

MiG21bis wrote:We do quite a bit of multiplayer work in v2 and now v3, and noticed that the spoiler (speed brake for us) variable is apparently not transmitted? Are we set up incorrectly, or did P3D actually reduce functionality in this respect? I'd expect LM to continually expand the usable variables, not to restrict them and reduce realism.

For military multi-ship ops, being able to call and see each others' "boards" is important.
I am NOT answering for LM, but would make the following observation and comment.

Ever since the first release of MS FSX, the spoiler data transmitted in Multiplayer has had issues.

MS chose to transmit Spoiler information in MP, as an Update, every time the spoiler value changed.
Bear in mind that the spoiler value is 16 bit resolution.

If spoiler value to coupled to a "noisy" Pot analogue generated variable, or is made a function of some other rapidly changing variable, ( typically done in Non_Spoiler aircraft to simulate some other aerodynamic effect) , then the Spoiler Updated packet gets sent every time that spoiler value changes, even if it only changes by 1 bit .

This lead to the common potential of massive Packet flooding of spoiler events packets in MP, often causing MP to grind to a halt due to packet overload.

In hindsight, MS might have done better to have included the Spoiler Value, in the Packet structure of the packet that send other analogue values, such as elevator, rudder etc, that is send every 5 seconds.

This was suggested to LM is some time ago in this forum.

HOPEFULLY, LM is doing something to address this issue, by removing the "Change in spoiler value=MP packet transmission", and adding it into 5 /sec update packet... but this is not completed/working.

From what I can see, doing so would not adversely affect any existing plane's operation in Free Flight, MP or Shared Cockpit, but would ONCE AN FOR ALL, end Spoiler event flooding in MP.
MiG21bis
Posts: 17
Joined: Wed Apr 03, 2013 7:22 pm

Re: Spoiler variable not transmitted in MP (v2 and v3)

Post by MiG21bis »

Informative post, FSMP - thanks for sharing the history, and your proposed solution seems optimal.

Surprising LM hasn't addressed this yet in their "military grade" sim system, but hopefully will soon.
FSMP
Posts: 678
Joined: Sat Sep 25, 2010 9:38 am

Re: Spoiler variable not transmitted in MP (v2 and v3)

Post by FSMP »

FSMP wrote:
In hindsight, MS might have done better to have included the Spoiler Value, in the Packet structure of the packet that send other analogue values, such as elevator, rudder etc, that is send every 5 seconds.
CORRECTION.

should have been "that is sent 5 times / second"
Clifton Crane
Lockheed Martin
Posts: 1207
Joined: Tue Sep 25, 2012 2:34 pm

Re: Spoiler variable not transmitted in MP (v2 and v3)

Post by Clifton Crane »

Hello MiG21bis,

Is this an issue you are seeing with all aircraft? Does the aircraft have the "spoiler_handle_available" flag set to 1 in the aircraft.cfg file?

The spoiler position is still serialized in multiplayer and was moved to the lower update packet a couple years ago. I believe this change made it into v2, however I am not sure which minor version specifically.
Clifton Crane
Prepar3D® Software Engineer Sr.
MiG21bis
Posts: 17
Joined: Wed Apr 03, 2013 7:22 pm

Re: Spoiler variable not transmitted in MP (v2 and v3)

Post by MiG21bis »

Clifton, good questions - I will investigate and report back. Fantastic if the fix is this easy.

Specifically, we saw this issue most recently using the excellent Lotus L39 in P3Dv3. When Lead calls the boards, his wingman can see a little jump in the panels - they pop out maybe 1", then immediately retract.
MiG21bis
Posts: 17
Joined: Wed Apr 03, 2013 7:22 pm

Re: Spoiler variable not transmitted in MP (v2 and v3)

Post by MiG21bis »

Clifton, "spoiler_handle_available" flag is set to 1 in our Lotus L39 example - yet doesn't transmit status to wingman. Anything else we can look at to resolve?
MiG21bis
Posts: 17
Joined: Wed Apr 03, 2013 7:22 pm

Re: Spoiler variable not transmitted in MP (v2 and v3)

Post by MiG21bis »

Clifton, I'm finding this to be the case in more and more aircraft, including the latest ones we're developing at MilViz: "spoiler_handle_available" flag set to 1, yet in no case are participants able to see each other's spoiler states.

What is the source of this problem? I assume It's important for Lockheed to get a handle on this, since much of what you do is military-related - and formation work is central to military/tactical aviation. Losing this important visual cue is a step backward from the old sims, P3Dv1 and even FSX.
Clifton Crane
Lockheed Martin
Posts: 1207
Joined: Tue Sep 25, 2012 2:34 pm

Re: Spoiler variable not transmitted in MP (v2 and v3)

Post by Clifton Crane »

MiG21bis,

Can you confirm that spoiler animations are correctly working with default aircraft (Mooney Bravo is a good example)?
Clifton Crane
Prepar3D® Software Engineer Sr.
MiG21bis
Posts: 17
Joined: Wed Apr 03, 2013 7:22 pm

Re: Spoiler variable not transmitted in MP (v2 and v3)

Post by MiG21bis »

Clifton, are you asking if we can see each other's in MP?
Clifton Crane
Lockheed Martin
Posts: 1207
Joined: Tue Sep 25, 2012 2:34 pm

Re: Spoiler variable not transmitted in MP (v2 and v3)

Post by Clifton Crane »

MiG21bis,

Correct. With a default aircraft, do the spoilers appear correctly on both the host and the client machines?
Clifton Crane
Prepar3D® Software Engineer Sr.
MiG21bis
Posts: 17
Joined: Wed Apr 03, 2013 7:22 pm

Re: Spoiler variable not transmitted in MP (v2 and v3)

Post by MiG21bis »

Clifton, our MilViz team tested three default aircraft (Mooney, F-22, Learjet) and all had the same problem. They tested in v2 and saw exactly the same symptoms that I've seen in v3 multiplayer. Guests see no spoiler movement when others deploy or retract, and can see their own correctly moving when commanded.

Here's the interesting part that may point Lockheed to the cause: the HOST actually sees the spoilers "flicker" when guests deploy or retract. A very small movement, but always going instantly back to retracted position. To see this flicker, one must be in close formation. At any distance it is too small to see.

Any ideas on cause and fix?
FSMP
Posts: 678
Joined: Sat Sep 25, 2010 9:38 am

Re: Spoiler variable not transmitted in MP (v2 and v3)

Post by FSMP »

MiG21bis wrote:Clifton, our MilViz team tested three default aircraft (Mooney, F-22, Learjet) and all had the same problem. They tested in v2 and saw exactly the same symptoms that I've seen in v3 multiplayer. Guests see no spoiler movement when others deploy or retract, and can see their own correctly moving when commanded.

Here's the interesting part that may point Lockheed to the cause: the HOST actually sees the spoilers "flicker" when guests deploy or retract. A very small movement, but always going instantly back to retracted position. To see this flicker, one must be in close formation. At any distance it is too small to see.

Any ideas on cause and fix?
Given, ( that in your group's configuration/setup), that Guests cannot see other Guest's spoiler movements, and that the Host can see a slight "Flicker" when Guests move their spoilers, what might help would be to know if Guests can correctly see the Host's spoilers.

The Host is receiving all the Guests spoiler's information, and passing it back to the other Guests, as well as sending out it's own (Hosts) spoiler information. Knowing if the Guests can see the HOST's spoiler information, would go a long way to determining what might be causing your issue.

=====
The other symptom of this issue that seems strange, is that this situation does not seem to be readily reproducible by LM.
Your group is most likely running over the Internet .. LM might only be testing over am internal Lan, which "Might" have something to do with the Reproducibility

Another symptom, that "might" be relevant, is that some are now reporting a Multiplayer Sim rate acceleration, that was, in the past of FSX development, dues to a Multiplayer synchronization issue, that was only apparent when FSX Multiplayer was running over a potentially slow/lagging Internet connection. -- Your issues could be interpreted also as being caused by a Multiplayer synchronization issue, although why your issues only apply to Spoilers, and not also to other information on the same Position update packet is an interesting question.(ie elevator, rudder position etc).
MiG21bis
Posts: 17
Joined: Wed Apr 03, 2013 7:22 pm

Re: Spoiler variable not transmitted in MP (v2 and v3)

Post by MiG21bis »

Great question, FSMP ("Can guests see hosts spoiler status?"). Will test and post here ASAP.
wiltzu
Posts: 34
Joined: Wed Sep 28, 2011 2:46 pm

Re: Spoiler variable not transmitted in MP (v2 and v3)

Post by wiltzu »

Have been testing as well as a guest to multiple hosts, have never seen it.
Locked