Odd escort behaviour

Post by **Disembodied** » Sun Sep 19, 2010 1:22 pm

Coming in to the aegis, I stopped to scan an open wormhole and I saw a bunch of (clean) escorts behaving oddly. One (a Mamba) was endlessly looping over and over beside the wormhole, which still had over a minute to go before it collapsed; two others (Sidewinders) were flying up near to the wormhole, turning around, heading back towards the station, turning around, heading back out to the wormhole again ... eventually the hole collapsed, but the behaviour continued. I docked and relaunched, and the Mamba at least was still there, looping the loop near where the wormhole (left, I presume, by its mother) used to be. Using v. 1.74.2.

Post by **Eric Walch** » Sun Sep 19, 2010 3:03 pm

I don't know exactly what happened. But in 1.73 (with the introduction of the wormhole scanner) something similar did happen more often:

A mothership launched with part of its escorts. Than an other, arriving ship requested docking permission and the remaining escorts had to wait. In the mean time the mother "wormholed" away. As long as the wormhole existed, the mother was kept in memory to allow for the player to follow. Only when the wormhole collapsed, the mother was removed from memory.

Now, with the wormhole scanner, the same thing happens when the wormhole is not scanned. But, when the player scans the wormhole, oolite has to keep the mother in memory to allow the player to meet with him with another route. However, while the mother has passed the wormhole, its actual coordinates have not changed. Also the coordinates of the escort positions have not changed.

Mom only tells its escorts to change from escorting to go to the wormhole on creation of the wormhole. All escorts that are still docked while mom jumps away will start escorting on launch. These are the imaginary escort positions on both sides of the wormhole. When I noticed this bug, I changed the code so that escorts launch would not be interrupted by docking ships. With an anaconda and 6 escorts all escorts were always launched before mom started with its jump.

But I can imagine that a much faster ship with many escorts still can manage to jump before the last escort was launched. When you would not have targeted the wormhole, mom would have been removed on wormhole collapse and the escorts would start looking for a new job. So I assume you examined the wormhole and mom stayed in memory after collapse and the escorts still were tumbling around that imaginary escort position.

The interesting part of wormholes is that they are stored in the save file since 1.73. However, almost nobody will realise that they meet such a stored ship after jumping. This is because the player will only see the ship at the witchpoint entry at the other side when he immediately follows the ship. When the player first docks, the clock will be advanced by 10 minutes on launch. But the clock will be also advanced for the jumped ship and the ship is positioned at a location consistent with its last known speed multiplied with the passed time. For a saved game, this always means that the player must have docked. So, when the player does follow a ship from a saved game, the jumped ship will be somewhere along the spacelane and the average player will never realise this is a specific ship from a wormhole and not just a ship added by the populator.
At first I thought it was a bug when I did not find the ships from the saved game at the other side at the witchpoint. Only after some time I realised that when starting from a saved game, there always will be a 10 minute time gap created by the launch.

Commander McLane · Post by **Commander McLane** » Sun Sep 19, 2010 3:03 pm

That happens when the mother and her escorts don't form a proper group. The mother jumps out and gives its escorts the command to follow. The escorts however—not being properly in the same group—don't receive the command.

It would be helpful to know what the mother was. Could you next time it happens scan one of the escorts, then enter the wormhole and scan the mother as well on the other side? Comparing the two could give valuable hints (for instance a different legal status).

EDIT: Eric's explanation seems better (and is obviously better informed).

Switeck · Post by **Switeck** » Mon Sep 20, 2010 12:06 am

Eric Walch wrote:
When I noticed this bug, I changed the code so that escorts launch would not be interrupted by docking ships. With an anaconda and 6 escorts all escorts were always launched before mom started with its jump.

This will probably be a lethal change to me.

I'm already getting rammed infrequently by launching ships, so much so that I request docking clearance on nearly all stations just to give myself a "safer" time window to dock.

A couple other possible workarounds for this would be:
1.Having escorts launched MUCH quicker after their mothership launches.
2.Having the mothership wait till all its escorts are within ~5 km of it before initiating a wormhole.
3.Escorts left chasing "virtual" mothership coordinates should assume new roles or switch to escorting something else if/when the wormhole closes.

JazHaz · Post by **JazHaz** » Mon Sep 20, 2010 6:03 am

Switeck wrote:
A couple other possible workarounds for this would be:
1.Having escorts launched MUCH quicker after their mothership launches.
2.Having the mothership wait till all its escorts are within ~5 km of it before initiating a wormhole.
3.Escorts left chasing "virtual" mothership coordinates should assume new roles or switch to escorting something else if/when the wormhole closes.

I reckon that the 2nd option would be the most realistic.

Post by **Eric Walch** » Mon Sep 20, 2010 7:27 am

Switeck wrote:
I'm already getting rammed infrequently by launching ships, so much so that I request docking clearance on nearly all stations just to give myself a "safer" time window to dock.

Should not happen. There is an explicit check to launch no ship when there is something immediately in front of the dock. And as far as I noticed it still works perfect.
Only stations in red-alert condition just launch without checking to get their defense ships out as fast as possible.

maik · Post by **maik** » Mon Sep 20, 2010 7:58 am

JazHaz wrote:
Switeck wrote:
A couple other possible workarounds for this would be:
1.Having escorts launched MUCH quicker after their mothership launches.
2.Having the mothership wait till all its escorts are within ~5 km of it before initiating a wormhole.
3.Escorts left chasing "virtual" mothership coordinates should assume new roles or switch to escorting something else if/when the wormhole closes.
I reckon that the 2nd option would be the most realistic.

Me too, but it would need a timer, e.g. the mother ship leaves after 5 minutes and escorts that only leave the station afterwards will need to assume a new role, i.e. follow option 3 in the above list.

Post by **Eric Walch** » Mon Sep 20, 2010 8:15 am

The most simple solution for these rare artifacts will be to just set the position of the disappearing ship to some fancy, far away position and not leaving it hanging around on the old wormhole position after a jump. After all, the ship is supposed to go through witchspace (wherever that is in coordinates)
When the bug than happens, the escorts just will fly away to that fancy location and nobody will notice.

Switeck · Post by **Switeck** » Tue Sep 21, 2010 1:15 am

EscortAI.plist should already adapt to losing their mothership, so as long as it actually works...just use it. Might be cool for a Boa, Boa2, or Python to get >4 escorts due to the big trader/s before them leaving too soon for all its escorts to join it.

Post by **Eric Walch** » Thu Sep 23, 2010 6:27 pm

Switeck wrote:
EscortAI.plist should already adapt to losing their mothership, so as long as it actually works...just use it. Might be cool for a Boa, Boa2, or Python to get >4 escorts due to the big trader/s before them leaving too soon for all its escorts to join it.

I just realised that it won't work. As soon as mom enters hyperspace, the updating of mom will stop and mom will never be able to tell her escorts about any new position.

I now solved it different by including a check for having status_in_flight during the regular checks for a mother being present. That way an escort will no longer try to escort a ship that is already in witchspace. When the escort has missed the instruction to fly to the wormhole, it will just become a lone escort on the look for a new career (or a new mother). That way all other kind of similar behaviour can be avoided. In future the status of witchspacing ships will be status_entering_witchspace.

e.g. things also could go wrong when there is a lone escort around that tries to find a new mother. Currently it is possible that the negotiation started just before the jump and mom accepts such an escort just after the jump giving the same behaviour as above.

Commander Smivs · Post by **Smivs** » Thu Sep 23, 2010 7:20 pm

Eric Walch wrote:
it will just become a lone escort on the look for a new career (or a new mother).

Could it be arranged that, if the first ship it encounters is the player it 'adopts' the player ship as 'Mother' and escorts you.

Darkbee · Post by **Darkbee** » Thu Sep 23, 2010 7:27 pm

Smivs wrote:
Eric Walch wrote:
it will just become a lone escort on the look for a new career (or a new mother).
Could it be arranged that, if the first ship it encounters is the player it 'adopts' the player ship as 'Mother' and escorts you.

*coughs: pansy*

Wiki pages · Post by **Thargoid** » Thu Sep 23, 2010 7:29 pm

IIRC player ships getting escorts is explicitly blocked within the trunk code.

Hence why I wrote Hired Guns

Commander McLane · Post by **Commander McLane** » Fri Sep 24, 2010 12:58 pm

Thargoid wrote:
IIRC player ships getting escorts is explicitly blocked within the trunk code.

Indeed. All interaction between mother and escorts is done in the AI.

Player ship = no AI.

Hence no possible interaction with escorts.