Adding Light component to "batteryPack" part's indicator

[InfamyKing]

Hello everyone! So as to train myself in the art of KSP modding, I am attempting to develop my first mod. Its purpose is simple: adding a Light emitting component to the z-100Battery indicator, the little green bell-shaped thing on top of the part. However, I've hit a roadblock. The following error (from the log file) has been haunting me for the past day or so:

Spoiler

[LOG 23:48:46.860] PartLoader: Compiling Part 'Squad/Parts/Electrical/z-100Battery/z-100Battery/batteryPack'
[EXC 23:48:46.866] TypeLoadException: Could not load type 'System.Runtime.CompilerServices.IteratorStateMachineAttribute' from assembly 'BatteryIndicatorLight'.
	System.MonoCustomAttrs.GetCustomAttributesBase (ICustomAttributeProvider obj, System.Type attributeType)
	System.MonoCustomAttrs.GetCustomAttributes (ICustomAttributeProvider obj, System.Type attributeType, Boolean inherit)
	System.MonoType.GetCustomAttributes (System.Type attributeType, Boolean inherit)
	UnityEngine.AttributeHelperEngine.GetParentTypeDisallowingMultipleInclusion (System.Type type)
	UnityEngine.GameObject:AddComponent(Type)
	Part:AddModule(String, Boolean)
	Part:AddModule(ConfigNode, Boolean)
	PartLoader:ParsePart(UrlConfig, ConfigNode)
	:MoveNext()
	UnityEngine.SetupCoroutine:InvokeMoveNext(IEnumerator, IntPtr)
[EXC 23:48:46.871] TypeLoadException: Could not load type 'System.Runtime.CompilerServices.IteratorStateMachineAttribute' from assembly 'BatteryIndicatorLight'.
	System.MonoCustomAttrs.GetCustomAttributesBase (ICustomAttributeProvider obj, System.Type attributeType)
	System.MonoCustomAttrs.GetCustomAttributes (ICustomAttributeProvider obj, System.Type attributeType, Boolean inherit)
	System.Reflection.MonoMethod.GetCustomAttributes (System.Type attributeType, Boolean inherit)
	BaseEventList+ReflectedData..ctor (System.Type type)
	BaseEventList.GetReflectedAttributes (System.Type type)
	BaseEventList.CreateDelegates (System.Object part)
	BaseEventList..ctor (.Part part, .PartModule module)
	PartModule.ModularSetup ()
	PartModule.Awake ()
	UnityEngine.GameObject:AddComponent(Type)
	Part:AddModule(String, Boolean)
	Part:AddModule(ConfigNode, Boolean)
	PartLoader:ParsePart(UrlConfig, ConfigNode)
	:MoveNext()
	UnityEngine.SetupCoroutine:InvokeMoveNext(IEnumerator, IntPtr)
[ERR 23:48:46.876] PartLoader: Encountered exception during compilation. System.NullReferenceException: Object reference not set to an instance of an object
  at PartModule.Load (.ConfigNode node) [0x00000] in <filename unknown>:0 
  at Part.AddModule (.ConfigNode node, Boolean forceAwake) [0x00000] in <filename unknown>:0 
  at PartLoader.ParsePart (.UrlConfig urlConfig, .ConfigNode node) [0x00000] in <filename unknown>:0 
  at PartLoader+.MoveNext () [0x00000] in <filename unknown>:0 

[ERR 23:48:46.877] PartCompiler: Cannot compile part

 

This results in the part not even loading, obviously.

The mod consists of 2 files:

• BatteryIndicatorLight.dll

Spoiler

using System;
using System.Collections;
using UnityEngine;

namespace BatteryIndicatorLight
{
    public class BatteryIndicatorLight : PartModule
    {
        //Variables:
        [KSPField]
        public float lightDuration = 1f;
        [KSPField]
        public float lightIntensity = 10f;
        [KSPField]
        public float lightRange = 15f;

        private Material lightMaterial = null;
        private PartResource electricCharge = null;

        public Light batteryIndicatorLight = null;

        private void GetLightMaterial()
        {
            int i = 0;
            Transform[] ts = part.GetComponentsInChildren<Transform>();
            while (i < ts.Length && lightMaterial == null)
            {
                Renderer renderer = ts[i++].GetComponent<Renderer>();
                if (renderer != null && renderer.material != null && renderer.material.name.Contains("light"))
                    lightMaterial = renderer.material;
            }
            electricCharge = part.Resources["ElectricCharge"];
        }

        public override void OnStart(PartModule.StartState state)
        {
            try
            {
                if (state == StartState.Editor || state == StartState.None)
                {
                    return; //Beware the bugs!
                }

                this.GetLightMaterial();

                if (lightMaterial != null)
                {
                    Debug.Log("[BatteryIndicatorLight] lightMaterial.name = " + lightMaterial.name);
                    GameObject batteryIndicatorLightGM = new GameObject();
                    batteryIndicatorLightGM.AddComponent<Light>();
                    batteryIndicatorLightGM.transform.position = part.transform.position;
                    batteryIndicatorLightGM.transform.parent = part.transform.parent;
                    //batteryIndicatorLightGM.transform.rotation = part.transform.rotation;
                    //part.transform.up

                    batteryIndicatorLightGM.GetComponent<Light>().enabled = (electricCharge.amount > 0f) ? true : false;
                    batteryIndicatorLightGM.GetComponent<Light>().range = lightRange;
                    batteryIndicatorLightGM.GetComponent<Light>().intensity = lightIntensity;
                    batteryIndicatorLightGM.GetComponent<Light>().color = lightMaterial.color; // new Color(lightRed, lightGreen, lightBlue);
                    Debug.Log(String.Format("[BatteryIndicatorLight] Light Material Color = ({0}, {1}, {2}, {3})",
                                            lightMaterial.color.r, lightMaterial.color.g, lightMaterial.color.b, lightMaterial.color.a));

                    batteryIndicatorLight = batteryIndicatorLightGM.GetComponent<Light>();
                } 
                else
                {
                    Debug.Log("[BatteryIndicatorLight] no lightMaterial found");
                }
                //base.OnStart(state);
            }
            catch (Exception e)
            {
                Debug.LogError("[BatteryIndicatorLight] Error onStart: " + e.Message);
            }
        }

        public override void OnUpdate()
        {
            try
            {
                if (batteryIndicatorLight != null)
                {
                    if (electricCharge.amount > 0f)
                    {
                        batteryIndicatorLight.color = lightMaterial.color;
                    }
                    else
                    {
                        StartCoroutine("shutLightDown");
                    }
                }
            }
            catch (Exception e)
            {
                Debug.LogError("[BatteryIndicatorLight] Error onUpdate: " + e.Message);
            }
        }

        //Coroutines are really easy in C#/Unity
        IEnumerator shutLightDown()
        {
            yield return new WaitForSeconds(lightDuration);
            batteryIndicatorLight.enabled = false;
        }
    }
}

 

• z-100Battery.cfg

Spoiler

@PART[batteryPack]
{
	MODULE
	{
		name = BatteryIndicatorLight
		lightDuration = 1.0
		lightIntensity = 10.0
		lightRange = 15.0
	}
}

 

Additionally, the file structure is as follows:

For reference, the code developed here is based on BatteryIndicator and EngineLightning. If anyone would be able to assist me in finding the cause of the error, I would be most grateful!

[Fwiffo]

You could also take a look at the IndicatorLights source code to see how that mod does it.

Edited October 22, 2016 by Fwiffo

[Diazo]

It's throwing an error on a method in the System namesapce, the only reason I can think that would happen is you're compiling against the wrong .NET level.

Check your project's properties and make sure you are compiling for .NET 3.5, not something newer.

D.

[InfamyKing]

Many thanks @Diazo, that was exactly my problem! I had no idea that the .NET framework level mattered in regards to KSP. I owe you one.

Also, I had no idea that mod existed @Fwiffo, thanks as well for sharing it here.