I’m new to unity and C#, so I’ve been trying to do a simple project and create a Solar System from script with the FX Planet Orbit script and specially with it’s C# version.
Making the planets gameObjects by hand in unity it works normally, but now that I’m trying to create the gameObject ( Mars ) from a script I’ve ran into a problem which I can’t figure out. I suspect it’s something simple and related to transforms in code below.
Mars is supposed to orbit Sun (obj_sun) by all the values I’ve set in CreatePlanet.cs, basicly trying to give all required variables which you give when making the gameObject from the Editor side.
I’ve spent more time with this than is healthy but I simply cannot seem to be able to do this. Any tips are appreciated as well, as you can see I’m just trying to make it work with simple logics here 
CreatePlanet.cs:
line 17: mars.GetComponent<TV_Orbit>().Parent = GameObject.Find("obj_sun").transform;
TV_Orbit.cs
line 85: OrbitCenter.position = Parent.position;
I get following error when trying to run the script:
NullReferenceException: Object reference not set to an instance of an object
TV_Orbit.Awake () (at Assets/Scripts/TV_Orbit.cs:85)
UnityEngine.GameObject:AddComponent(String)
CreatePlanet:Start() (at Assets/Scripts/CreatePlanet.cs:17)
My own script CreatePlanet.cs:
using UnityEngine;
using System.Collections;
public class CreatePlanet : MonoBehaviour {
// Use this for initialization
void Start () {
Debug.Log("I am alive!");
GameObject mars = GameObject.CreatePrimitive(PrimitiveType.Sphere);
//mars.transform.position = new Vector3(20f, 0, 0);
mars.name = "obj_mars";
mars.transform.localScale = new Vector3(1000, 1000, 1000);
mars.renderer.material.color = Color.red;
mars.transform.parent = GameObject.Find("obj_sun").transform;
mars.AddComponent("TV_Orbit");
mars.GetComponent<TV_Orbit>().OrbitalDistance = 2279.20f;
mars.GetComponent<TV_Orbit>().Parent = GameObject.Find("obj_sun").transform;
mars.GetComponent<TV_Orbit>().Parent.position = GameObject.Find("obj_sun").transform.position;
Debug.Log(GameObject.Find("obj_sun").transform.position);
mars.GetComponent<TV_Orbit>().TidalLock = false;
mars.GetComponent<TV_Orbit>().LockOrbit = false;
mars.GetComponent<TV_Orbit>().OrbitAngle = 1;
mars.GetComponent<TV_Orbit>().KeepTime = false;
mars.GetComponent<TV_Orbit>().OrbitOffset = new Vector3(0,0,0);
mars.GetComponent<TV_Orbit>().OrbitPosOffset = 0;
mars.GetComponent<TV_Orbit>().OrbitalPeriod = 1;
mars.GetComponent<TV_Orbit>().Name = "Mars";
mars.GetComponent<TV_Orbit>().RotationPeriod = 1.01f;
mars.GetComponent<TV_Orbit>().RotInOrbit = 686;
mars.GetComponent<TV_Orbit>()._DrawOrbit = true;
mars.GetComponent<TV_Orbit>().AxialTilt = 25.19f;
mars.GetComponent<TV_Orbit>().enabled = true;
}
// Update is called once per frame
void Update () {
}
}
FX Planet Orbit TV_Orbit.cs which I’ve attached to the gameObjects:
using UnityEngine;
using System.Collections;
public class TV_Orbit : MonoBehaviour {
public int TimeMultiplier = 200000;
public string Name = "";
public Transform Parent;
public enum Orbit {Auto, Manual}
public Orbit SetOrbit;
public enum Rotation {Auto, Manual}
public Rotation SetRotation;
public enum Season {Auto, Manual}
public Season SetSeason;
public bool TidalLock;
public bool LockOrbit;
public float OrbitAngle;
public bool KeepTime;
private Transform ThisTransform;
private float EarthDays = 365.242199f;
// Orbit Stats
public float OrbitalPeriod = 1.0f; // Earth Years
public float OrbitalDistance = 2f;
public Vector3 OrbitOffset;
public float OrbitPosOffset;
public float OrbitStartPos;
public int OrbitYears;
public int OrbitDays;
public int OrbitHours;
public int OrbitMinutes;
public float OrbitSeconds;
private float OrbitalTime;
private float OrbitalDegSec;
//Rotation Stats
public float RotationOffset;
public float RotationPeriod; // Earth Hours
public int RotationYears;
public int RotationDays;
public int RotationHours;
public int RotationMinutes;
public float RotationSeconds;
private float RotationDegSec;
private float RotationTime;
// Planetary Stats
public float AxialTilt;
public int HoursInDay;
public int RotInOrbit;
//Planet Counters
public int CounterYear;
public int CounterDay;
public int CounterHour;
public int CounterMinute;
public float CounterSecond;
public float CurrentOrbitPos;
public bool OrbitOffSetYear;
private float RotCounter;
private float OrbCounter;
//Draw Orbit
public bool _DrawOrbit = false;
public float DisplaySize = 0.05f;
public Color DisplayColor = Color.blue;
public int Segments = 100;
public Texture2D DisplayTexture;
public int DisplayTiling = 50;
public bool UseTexture;
private Transform ThisOrbit;
private LineRenderer LR;
private Transform OrbitCenter;
public void Awake(){
ThisTransform = transform;
var ThisLEuler = ThisTransform.localEulerAngles;
ThisLEuler.z = AxialTilt;
ThisTransform.localEulerAngles = ThisLEuler;
OrbitCenter = new GameObject("OrbitCenter").transform;
OrbitCenter.position = Parent.position;
ThisTransform.parent = OrbitCenter;
ThisTransform.localPosition = new Vector3(0,0,OrbitalDistance);
var OCEuler = OrbitCenter.eulerAngles;
OCEuler.x = OrbitAngle;
OrbitCenter.eulerAngles = OCEuler;
OrbitCenter.Rotate(0,OrbitPosOffset,0);
if(_DrawOrbit){
if(GameObject.Find("Orbits") == null){
GameObject Orbits = new GameObject("Orbits");
Orbits.transform.position = Vector3.zero;
Orbits.transform.eulerAngles = Vector3.zero;
}
}
}
public void Start(){
SetupPlanet();
if(OrbitOffSetYear){
OrbCounter = OrbitPosOffset;
}
if(LockOrbit){
KeepTime = false;
}
if(_DrawOrbit){
SetupDrawOrbit();
}
}
public void SetupDrawOrbit(){
GameObject Orbit = new GameObject("Orbit_Path");
GameObject Obits = GameObject.Find("Orbits");
var OrbEA = Orbit.transform.eulerAngles;
OrbEA.x = OrbitAngle;
Orbit.transform.eulerAngles = OrbEA;
Orbit.transform.parent = Obits.transform;
Orbit.transform.position = Parent.position;
Orbit.AddComponent<LineRenderer>();
LR = Orbit.GetComponent<LineRenderer>();
LR.SetWidth(DisplaySize,DisplaySize);
LR.material.shader = Shader.Find("Particles/Additive");
LR.material.SetColor ("_TintColor", DisplayColor);
LR.useWorldSpace = false;
LR.SetVertexCount (Segments + 1);
if(DisplayTexture != null){
var mTScale = LR.material.mainTextureScale;
LR.material.mainTexture = DisplayTexture;
mTScale.x = DisplayTiling;
LR.material.mainTextureScale = mTScale;
}
ThisOrbit = Orbit.transform;
float Angle = new float();
for (int i = 0; i < (Segments + 1); i++){
Vector2 NewRadius = new Vector2(Mathf.Sin ( Mathf.Deg2Rad * Angle) * OrbitalDistance,
Mathf.Cos (Mathf.Deg2Rad * Angle) * OrbitalDistance);
LR.SetPosition (i,new Vector3(NewRadius.y,0,NewRadius.x));
Angle += (float)(360.0 / Segments);
}
}
public void SetupPlanet(){
//Setup Orbit Time
if(SetOrbit == 0){
OrbitalTime = ((((EarthDays * OrbitalPeriod) * 24) * 60) * 60);
OrbitalDegSec = (360 / OrbitalTime) * TimeMultiplier;
}else{
OrbitalPeriod = 0;
OrbitalTime = ((((((((OrbitYears * EarthDays) + OrbitDays) * 24) + OrbitHours) * 60) + OrbitMinutes) * 60) + OrbitSeconds);
OrbitalDegSec = (360 / OrbitalTime) * TimeMultiplier;
}
//Setup Rotation Time
if(!TidalLock){
if(SetRotation == 0){
RotationTime = (((24 * RotationPeriod) * 60) * 60);
RotationDegSec = (360 / OrbitalTime) * TimeMultiplier;
}else{
RotationPeriod = 0;
RotationTime = ((((((((RotationYears * EarthDays) + RotationDays) * 24) + RotationHours) * 60) + RotationMinutes) * 60) + RotationSeconds);
}
RotationDegSec = (360 / RotationTime) * TimeMultiplier;
RotInOrbit = Mathf.RoundToInt(OrbitalTime / RotationTime);
HoursInDay = Mathf.RoundToInt((RotationTime / 60) / 60);
}
}
public void Update(){
float ODS = OrbitalDegSec * Time.deltaTime;
if(!LockOrbit){
OrbitStartPos += ODS;
OrbitCenter.Rotate(0,ODS,0);
}
// Update Rotation
if(TidalLock){
ThisTransform.LookAt(Parent);
if(KeepTime){
UpdateCounters(0f, ODS);
}
}else{
float RotDegSec = RotationDegSec * Time.deltaTime;
if(KeepTime){
UpdateCounters(RotDegSec, ODS);
}
ThisTransform.Rotate(0,RotDegSec, 0, Space.Self);
}
}
public void UpdateCounters(float RotDegSec ,float ODS ){
//Count Orbits / Years
if((OrbCounter + ODS) >= 360){
CounterYear += 1;
CounterDay = 0;
OrbCounter = (OrbCounter + ODS) - 360;
}else{
OrbCounter += ODS;
}
CurrentOrbitPos = OrbCounter;
//Count Days
if((RotCounter + RotDegSec)>= 360){
CounterDay += 1;
RotCounter = (RotCounter + RotDegSec) - 360;
}else{
RotCounter += RotDegSec;
}
var CurrentTime = (RotCounter / 360) * RotationTime;
//Count Hours
CounterHour = (int)(CurrentTime / 60) / 60;
//Count Minutes
if(CounterHour > 0){
CounterMinute = (int)(CurrentTime / 60) - (CounterHour * 60);
}else{
CounterMinute = (int)(CurrentTime / 60);
}
//Count Seconds
if(CounterHour > 0 && CounterMinute > 0){
CounterSecond = CurrentTime - ((CounterMinute + (CounterHour * 60)) * 60);
}else if(CounterHour > 0 && CounterMinute == 0){
CounterSecond = CurrentTime - ((CounterHour * 60) * 60);
}else if(CounterHour == 0 && CounterMinute > 0){
CounterSecond = CurrentTime - (CounterMinute * 60);
}else if(CounterHour == 0 && CounterMinute == 0){
CounterSecond = CurrentTime;
}
}
void LateUpdate(){
Vector3 CurPos = Parent.position + new Vector3(OrbitOffset.x, OrbitOffset.y,OrbitOffset.z);
OrbitCenter.position = CurPos;
if(_DrawOrbit){
ThisOrbit.position = CurPos;
}
}
}