Scripters cove

[kanthoney]

Pick a random direction, using randomDirection(). Then work out the direction of the sun / planet by subtracting the position of the entity from the position of the planet, and normalise that using the direction() function. You've now got two vectors which should both have a length of one.

Now take the dot product of the two vectors (using the dot() function, obviously), which should be a number between -1 and 1. A value of 1 means the vectors are in the same direction and -1 means they're pointing in exactly in the opposite directions. So if the dot product is more than, say, 0.95 you're heading roughly towards the planet and need to try a different direction.

Ref: http://wiki.alioth.net/index.php/Oolite ... :_Vector3D

[Norby]

I don't want the random direction to be into the sun or planet.

Here is my untested attempt to exclude the sun from a random direction.
The same should be checked for each items in system.planets array also.

Code: Select all

var pp = player.ship.position;
//heading from the player to the center of the sun
var h = sun.position.subtract(pp);
for(var i=0; i<100; i++) { //max. 100 retry
    var q = Quaternion.random();
    var qf = q.vectorForward();
    //angle from the center of the sun to the border of the disk
    if( Math.tan(qf.angleTo(h)) > sun.radius / pp.distanceTo(sun.position) ) {
        player.ship.orientation = q; //points out of the sun
        break;
    }
}

[phkb]

using the dot() function, obviously

I love the clever use of "obviously"...

[phkb]

Is it possible to leverage the built-in assassin system? For instance, could accepting or completing a mission increase the chance of assassins at the witchpoint? Or does it need an entirely separate approach (eg Random Hits)?

[cim]

Is it possible to leverage the built-in assassin system? For instance, could accepting or completing a mission increase the chance of assassins at the witchpoint? Or does it need an entirely separate approach (eg Random Hits)?

Give your mission script a custom populator, and have it add extra assassins sometimes. You can either add a separate myoxp-bonus-assassins entry, or override the existing "oolite-assassins" entry to one with a higher group count and/or a tougher callback function.

To get them to attack you have a few options:
- give the player a high-risk parcel or passenger for some parts of the mission
- add trader-courier+ to the player's role set a few times
- (probably better) add myoxp-mission-protagonist+ to the player's role set a few times, and use Role-categories.plist to add it to the oolite-courier role group.
(The plus on the end prevents distance-related decay of roles, which you probably want in this case)

You might also want to add an extra assassin personality to the comms array, conditional on the player having attracted these specific assassins, so that sometimes they can say "there's the pilot who offended the vice-Duke!" or whatever the mission is about.

[phkb]

Thanks for the previous response, cim.

Another question: Is it possible to remove a particular system ID as a witchspace destination for NPC's? The idea being to quarantine a system for whatever reason. I realise I can just add a timer or a frame callback and monitor all ships with hyperspace engines and check their destinationSystem property, but I was hoping for something a little more direct.

[phkb]

A question for any Vector experts out there...

How can you work out if a ship is on a particular lane? I can see that "entity" has a "position" vector, and a vector has a "toCoordinateSystem" method. So if I do something like this:

Code: Select all

var vect = myNPCShip.position.toCoordinateSystem("wpu");
log(this.name, "vect = " + vect.x + ", " + vect.y + ", " + vect.z);

and then running something like it over a few ships returns these results:

13:51:21.006 [myOXP]: ship = [Ship "Night Adder" position: (-16739.1, -33957.8, 309128) scanClass: CLASS_NEUTRAL status: STATUS_IN_FLIGHT]
13:51:21.006 [myOXP]: vect = 0.05546399538012031, 0.07352871999922404, 0.7520263813183803
13:51:21.006 [myOXP]: ship = [Ship "Python" position: (5878.13, -45060.9, 34723.5) scanClass: CLASS_NEUTRAL status: STATUS_IN_FLIGHT]
13:51:21.006 [myOXP]: vect = 0.006470267535101524, 0.11036057068886841, 0.08447313493024122
13:51:21.006 [myOXP]: ship = [Ship "Bug" position: (2346.88, -29148.4, -15840.6) scanClass: CLASS_NEUTRAL status: STATUS_IN_FLIGHT]
13:51:21.006 [myOXP]: vect = 0.007663652896847149, 0.07072589638477839, -0.038536007153059604
13:51:21.006 [myOXP]: ship = [Ship "Cobra Mark III" position: (-371164, -98700.6, -106782) scanClass: CLASS_NEUTRAL status: STATUS_IN_FLIGHT]
13:51:21.006 [myOXP]: vect = 0.9319277605848015, 0.06686805118676767, -0.2597719691820526

Would any of these numbers indicate a ship on the witchpoint-planet lane?

[Norby]

First you should define what you mean "on lane", for example within 2*scanner range (51200m) from the wp line.

Then use wpm where coords are in meters to be comparable with the selected width of lane. The 3. coordinate mean nothing for you (show the position along the lane) but the first two are two sides of a right triangle where the length of the third side (using Pythagorean theorem) is what you want to compare with the width of lane.

Another way: ............ Ship
PlanetWitchpoint

The "b" side is the wp lane (witchpoint is at origo so b is equal with system.mainPlanet.position), "a" is myNPCShip.position, gamma is a.angleTo(b) in radians what Math.sin() need. So you can do something like this (untested):

Code: Select all

var a = myNPCShip.position, p = system.mainPlanet;
if( a && p && a.magnitude() * Math.sin( a.angleTo(p.position) ) < 51200) {
    //myNPCShip is in wp lane
}

The check of "a" could prevent problems with destroyed NPCs, the check of planet is useful in interstellar space.

Usually worth count ships in Witchpoint-Main Station line also.

[phkb]

Thanks for the previous answer, Norby!

Another question: What would be the best way to reliably determine what alloys and wreckage were created with the destruction of a particular ship?

[Norby]

what alloys and wreckage were created with the destruction of a particular ship?

Just an idea:
- in shipDied event save the time and position (could be tricky if ship is not valid anymore),
- in shipSpawned check if it is an alloy/wreckage, then compare the time and position with saved destructions and if it is "enough near" then assume it is crearted by that ship,
- remove old entries from the saved list after a sure timeout in a timer.

[NEANDERTHAL]

How could one store a set amount of data for each system, and read/write as well as store that data for later use? For example, I want to save the amount of entities in each system for later reference. Would I have to store the data in the system description space? Could I keep this data in a script-generated file?

[Norby]

The script in SMax's MFDRestoreAfterLoad contain a nice example how to save an array of data into the savegame using JSON to convert it to string and load back in the startUp event.

Your array should be a property of your script so define it as this._YourArray = []; (like this.name at the top of the script) and use as this._YourArray[0] = 123; within your functions.

[NEANDERTHAL]

What does cargo_type = "CARGO_THARGOID" in shipdata.plist do exactly?

[phkb]

I'm not 100% sure, but I think that makes the item scoopable as Alien Items.

[phkb]

Is it possible to check whether a particular ship can fit through the docking port of a station? Without, you know, actually trying.