UnityEditor.AudioUtil.GetCustomFilterChannelCount C# (CSharp) Method

        public static extern int GetCustomFilterChannelCount(MonoBehaviour behaviour);
        [MethodImpl(MethodImplOptions.InternalCall), WrapperlessIcall]

        public void DrawAudioFilterGUI(MonoBehaviour behaviour)
        {
            int customFilterChannelCount = AudioUtil.GetCustomFilterChannelCount(behaviour);

            if (customFilterChannelCount > 0)
            {
                if (this.dataOut == null)
                {
                    this.dataOut = new EditorGUI.VUMeter.SmoothingData[customFilterChannelCount];
                }
                double num2 = ((double)AudioUtil.GetCustomFilterProcessTime(behaviour)) / 1000000.0;
                float  r    = ((float)num2) / ((((float)AudioSettings.outputSampleRate) / 1024f) / ((float)customFilterChannelCount));
                GUILayout.BeginHorizontal(new GUILayoutOption[0]);
                GUILayout.Space(13f);
                GUILayout.BeginVertical(new GUILayoutOption[0]);
                EditorGUILayout.Space();
                for (int i = 0; i < customFilterChannelCount; i++)
                {
                    GUILayoutOption[] optionArray1 = new GUILayoutOption[] { GUILayout.MinWidth(50f), GUILayout.Height(5f) };
                    EditorGUILayout.VUMeterHorizontal(AudioUtil.GetCustomFilterMaxOut(behaviour, i), ref this.dataOut[i], optionArray1);
                }
                GUILayout.EndVertical();
                Color color = GUI.color;
                GUI.color = new Color(r, 1f - r, 0f, 1f);
                GUILayoutOption[] options = new GUILayoutOption[] { GUILayout.MinWidth(40f), GUILayout.Height(20f) };
                GUILayout.Box($"{num2:00.00}ms", options);
                GUI.color = color;
                GUILayout.EndHorizontal();
                EditorGUILayout.Space();
                GUIView.current.Repaint();
            }
        }