InlineCurveEditor.cs

using UnityEngine;
using UnityEditor;
using System.Reflection;
using Type = System.Type;

public class InlineCurveEditor
{
  private object curveEditor;
  private Type curveType;

  private Type curveDataType;

  private Type cureWrapperGetCallbackType;
  private Type cureWrapperSetCallbackType;

  public InlineCurveEditor()
  {
    curveType = FindType("ParticleSystemCurveEditor");
    curveDataType = FindType("ParticleSystemCurveEditor+CurveData");
    cureWrapperGetCallbackType = FindType("CurveWrapper+GetAxisScalarsCallback");
    cureWrapperSetCallbackType = FindType("CurveWrapper+SetAxisScalarsCallback");

    var construct = curveType.GetConstructor(new Type[0]);
    curveEditor = construct.Invoke(new object[0]);

    var initMeth = curveType.GetMethod("Init");
    initMeth.Invoke(curveEditor, new object[0]);
  }

  private static Type SearchType(Type parentType, string name)
  {
    if (parentType.FullName.Contains(name))
    {
      return parentType;
    }

    foreach (var type in parentType.GetNestedTypes())
    {
      var res = SearchType(type, name);
      if (res != null)
      {
        return res;
      }
    }

    return null;
  }

  public static Type FindType(string name)
  {
    foreach (var assembly in System.AppDomain.CurrentDomain.GetAssemblies())
    {
      foreach (var type in assembly.GetTypes())
      {
        var res = SearchType(type, name);
        if (res != null)
        {
          return res;
        }
      }
    }
    return null;
  }

  public void AddCurve(SerializedProperty prop)
  {
    var types = new Type[] {
      typeof(string),
      typeof(GUIContent),
      typeof(SerializedProperty),
      typeof(SerializedProperty),
      typeof(Color),
      typeof(bool),
      cureWrapperGetCallbackType,
      cureWrapperSetCallbackType,
      typeof(bool)
    };

    var cdConstruct = curveDataType.GetConstructor(types);
    var cd = cdConstruct.Invoke(new object[] {
      prop.name,
      new GUIContent(prop.name),
      null,
      prop,
      Color.red,
      false,
      null,
      null,
      true
    });

    var addCurveMeth = curveType.GetMethod("AddCurve");
    addCurveMeth.Invoke(curveEditor, new object[] { cd });
  }

  public void OnGUI()
  {
    var height = 200;
    var rect = GUILayoutUtility.GetRect(13f, height, new GUILayoutOption[]
    {
      GUILayout.MinHeight(height)
    });

    var onGUIMeth = curveType.GetMethod("OnGUI");
    onGUIMeth.Invoke(curveEditor, new object[] { rect });
  }

}