Spawning a single part as a vessel in orbit

[oakwhiz]

I can't seem to figure out what the procedure is for taking a part and spawning it as a debris object in a particular orbit. I know that debris objects are just vessels, so I'm assuming that I have to create a Vessel, add a Part to the Vessel, add an Orbit to the Vessel, and then create a ProtoVessel from that Vessel. I haven't been able to find any documentation on instantiating a new vessel though.

Any pointers as to where I should start?

[Faark]

I would approach it the other way around: Create a savegame with your debris vessel, inspect its ConfigNodes and learn how to generate those ConfigNodes, then create the ProtoVessel from them and use its loading code...

[oakwhiz]

I tried the following code but it generates an exception in the chunk of code after "Set orbit params". I can't figure out what I'm doing wrong here. There has got to be a way to create a vessel dynamically.

            // Find the Kerbin CelestialBody
            CelestialBody kerbin = null;
            foreach (CelestialBody aBody in FlightGlobals.Bodies)
            {
                if (aBody.name == "Kerbin")
                {
                    kerbin = aBody;
                }
            }

            // Create a new blank vessel
            Vessel newVessel = new Vessel();

            // Add a part to the vessel
             Debug.Log("getPartInfoByName");
            AvailablePart ap = PartLoader.getPartInfoByName("cupola");
             Debug.Log("Instantiate");
            UnityEngine.Object obj = UnityEngine.Object.Instantiate(ap.partPrefab);
             Debug.Log("newPart");
            Part newPart = (Part)obj;
             Debug.Log("rootPart ; parts.Add()");
            newPart.gameObject.name = "cupola";
            newPart.partInfo = ap;
            newVessel.rootPart = newPart;
            newVessel.parts = new List<Part>();
            newVessel.parts.Add(newPart);

            // Set vessel parameters
             Debug.Log("Set vessel params");
            newVessel.Landed = false;
         	newVessel.Splashed = false;
         	newVessel.landedAt = string.Empty;
            newVessel.situation = Vessel.Situations.ORBITING;
            newVessel.vesselType = VesselType.Debris;

            // Set up an orbit for the vessel
             Debug.Log("Set orbit params");
            double utTime = Planetarium.GetUniversalTime();
            OrbitPhysicsManager.HoldVesselUnpack(180);
            // The next line tries to put the debris somewhere around the CelestialBody
            newVessel.orbit.UpdateFromStateVectors((UnityEngine.Random.onUnitSphere + UnityEngine.Random.insideUnitSphere) * 200000f, UnityEngine.Random.onUnitSphere * 5000f, kerbin, utTime);
            newVessel.orbit.Init();
            newVessel.orbit.UpdateFromUT(utTime);
            newVessel.orbitDriver.pos = newVessel.orbit.pos.xzy;
            newVessel.orbitDriver.vel = newVessel.orbit.vel;

			// Set rotation parameters
			newVessel.SetRotation(UnityEngine.Random.rotation);
            newVessel.angularMomentum = Vector3.zero;
            newVessel.angularVelocity = Vector3.zero;

            // ???
             Debug.Log("GoOnRails");
            newVessel.GoOnRails();

Output:

Set orbit params
[Exception]: NullReferenceException: Object reference not set to an instance of an object

[problemecium]

Any progress on this? Someday when I'm a more experienced modder I was considering trying to make the "other" space center launch ships randomly, although without the full launch simulation.