Oolite Bulletins

phkb wrote: ↑Fri Dec 17, 2021 11:39 am

Giving a ship the null AI (oolite-nullAI.js) would make it unresponsive, allowing you to then do whatever you want with the ship programmatically. Although I haven't tested every function, so it might not work.

another_commander wrote: ↑Fri Dec 17, 2021 2:24 pm

Check ship.destination and ship.desiredSpeed JS properties, also PriorityAIController.prototype.behaviourApproachDestination in Resources/Scripts/oolite-priorityai.js.

cim wrote: ↑Mon Feb 28, 2022 9:17 pm

All ships have to have an AI - but it is possible for that AI to avoid using any of the in-built flight code whatsoever. You just have to combine a bunch of obscure features ... but then, you were going to have to do that anyway.

Start with https://wiki.alioth.net/index.php/Oolit ... ScriptedAI (and the neighbouring ScriptedAttack if you want it to be able to shoot too). A very basic JS AI can set that AI mode off (you probably don't even need the priority AI library) - or you can also call it from a simple plist AI if you prefer.

That lets you then control a ship's flight model and laser fire directly with a callback function as described at https://wiki.alioth.net/index.php/OXP_Scripted_AI - that callback can as well as returning the future flight parameters, also do all the usual things like setting position, firing ECM, etc. And of course the Debug Console can update suitable shipscript variables to tell the callback function what it should be doing.

Note: if you're using this for multiplayer, there'll be a discrepancy:
- the player will fire the laser when they think they're going to hit
- the ship under ScriptedAttack will fire when its AI thinks it's going to hit (based on its accuracy parameter)
So if you want to fire if and only if the player does, you may need to make use of a huge virtual invisible target in the right direction, so it always thinks it's going to hit, and then only use ScriptedAttack on the frames it should actually fire.

As far as a basic example (untested, but you can probably figure out the bugs) goes:
Ship script (just use a null AI script with this one):

Code: Select all

this.flightParameters = {};

this.shipSpawned = function()
{
  this.performScriptedAI();
}

this.scriptedAI = function(delta) 
{
   return this.flightParameters;  
}

Debug console:

Code: Select all

ship.script.flightParameters = { stickPitch: -0.2; desiredSpeed: this.ship.maxSpeed / 3; }

Ship starts off stationary, when you enter the debug console code it should start doing slow pitch loops.

I am wondering why your description sounds just so much different from https://wiki.alioth.net/index.php/OXP_howto_AI, which talks about state machines.

I suspect this command would have to come via the Debug Console.

Could we create a working list of commands to be used on the Debug Console?

ships = system.addShips("trader", 1, [2000, 2000, 2000]); // near the witchpoint
ship = ships[0];
ship.commsMessage("Hello");

how would I spawn a ship that makes use of this AI

"aitest_adder" = {
       like_ship = "adder";
       is_external_dependency = yes;
       roles = "aitest";
       script = "my-ship-script.js"; // or whatever you called the file from my previous post
       ai_type = "nullAI.plist";
};

cim wrote: ↑Wed Mar 02, 2022 12:40 pm

I suspect this command would have to come via the Debug Console.

Yes, if your intent is to then control the ship from the debug console, that makes sense.

cim wrote: ↑Wed Mar 02, 2022 12:40 pm

System.addShips() would be the most straightforward way to add it, and returns a reference to the added ships which you can then access as a variable in the debug console.
https://wiki.alioth.net/index.php/Oolit ... m#addShips

Could we create a working list of commands to be used on the Debug Console?

Here you go - https://wiki.alioth.net/index.php/Oolit ... ject_model

Any JS method can be called from the debug console, and it has local variable storage to get the results back, and access to the standard Oolite worldscript globals like system. So you can do things like this to spawn a ship, get it into a local variable in the debug console, and then call Ship methods on that ship instance

Code: Select all

ships = system.addShips("trader", 1, [2000, 2000, 2000]); // near the witchpoint
ship = ships[0];
ship.commsMessage("Hello");

[[Ship "Boa Class Cruiser Leader" position: (3456.26, 1553.22, 10340.5) scanClass: CLASS_NEUTRAL status: STATUS_IN_FLIGHT]]

cim wrote: ↑Wed Mar 02, 2022 12:40 pm

how would I spawn a ship that makes use of this AI

At least just for early testing, I'd set up a new shipdata.plist entry, based on an existing ship but then overriding a few properties

Code: Select all

"aitest_adder" = {
       like_ship = "adder";
       is_external_dependency = yes;
       roles = "aitest";
       script = "my-ship-script.js"; // or whatever you called the file from my previous post
       ai_type = "nullAI.plist";
};

Then you can swap aitest for trader in the system.addShips call above and you've got one ready to use.

this.flightParameters = {};

this.shipSpawned = function()
{
  this.performScriptedAI();
}

this.scriptedAI = function(delta) 
{
   return this.flightParameters;  
}

"aitest_adder" = {
       like_ship = "adder";
       is_external_dependency = yes;
       roles = "aitest";
       script = "RemoteControlled.js"; // or whatever you called the file from my previous post
       ai_type = "nullAI.plist";
};

...
    AddOns/Crossplay.oxp
    AddOns/Basic-debug.oxp
...

ships = system.addShips("aitest", 1, [2000, 2000, 2000],1); 

null

cim wrote: ↑Thu Mar 03, 2022 9:08 am

Bearing in mind that it's been several years since I did any serious OXP coding, so others might be more able to help with this bit...

- your RemoteControlled.js file should go in Scripts/ not AIs/
- your shipdata.plist needs enclosing { and } to hold the aitest_adder entry

ship.script.flightParameters = { stickPitch: -0.2; desiredSpeed: this.ship.maxSpeed / 3; }

cim wrote: ↑Thu Mar 03, 2022 10:50 pm

Try giving it a kick with ship.performScriptedAI() in the console.

If that doesn't work, to make sure it's getting the right AI attached, try replacing the function with this.

Code: Select all

this.scriptedAI = function(delta) 
{
   log(ship.name, delta);
   return { stickPitch: -0.2; desiredSpeed: this.ship.maxSpeed / 3; }
}

If the AI mode is being set properly, that should force the movement pattern, and also fill your logfile with time fractions. If the AI mode isn't being set properly nothing happens - but doing ship.performScriptedAI() in the console should then set it off.

this.name = "Debug Control AI";

this.aiStarted = function()
{
this.ship.performScriptedAI()
}