UnityEditor.TextureUtil.GetStorageMemorySize C# (CSharp) Method

        public static extern int GetStorageMemorySize(Texture t);
        public static Vector4 GetTexelSizeVector(Texture t)

        private void Summary()
        {
            GUILayout.BeginVertical(EditorStyles.helpBox, new GUILayoutOption[0]);
            int bytes = 0;
            int num   = 0;
            Dictionary <Vector2, int> dictionary1 = new Dictionary <Vector2, int>();
            bool flag1 = false;

            foreach (LightmapData lightmap in LightmapSettings.lightmaps)
            {
                if (!((UnityEngine.Object)lightmap.lightmapFar == (UnityEngine.Object)null))
                {
                    ++num;
                    Vector2 key = new Vector2((float)lightmap.lightmapFar.width, (float)lightmap.lightmapFar.height);
                    if (dictionary1.ContainsKey(key))
                    {
                        Dictionary <Vector2, int> dictionary2;
                        Vector2 index;
                        (dictionary2 = dictionary1)[index = key] = dictionary2[index] + 1;
                    }
                    else
                    {
                        dictionary1.Add(key, 1);
                    }
                    bytes += TextureUtil.GetStorageMemorySize((Texture)lightmap.lightmapFar);
                    if ((bool)((UnityEngine.Object)lightmap.lightmapNear))
                    {
                        bytes += TextureUtil.GetStorageMemorySize((Texture)lightmap.lightmapNear);
                        flag1  = true;
                    }
                }
            }
            string str   = num.ToString() + (!flag1 ? " non-directional" : " directional") + " lightmap" + (num != 1 ? "s" : string.Empty);
            bool   flag2 = true;

            using (Dictionary <Vector2, int> .Enumerator enumerator = dictionary1.GetEnumerator())
            {
                while (enumerator.MoveNext())
                {
                    KeyValuePair <Vector2, int> current = enumerator.Current;
                    str  += !flag2 ? ", " : ": ";
                    flag2 = false;
                    if (current.Value > 1)
                    {
                        str = str + (object)current.Value + "x";
                    }
                    str = str + (object)current.Key.x + "x" + (object)current.Key.y + "px";
                }
            }
            GUILayout.BeginHorizontal();
            GUILayout.BeginVertical();
            GUILayout.Label(str + " ", LightingWindow.styles.labelStyle, new GUILayoutOption[0]);
            GUILayout.EndVertical();
            GUILayout.BeginVertical();
            GUILayout.Label(EditorUtility.FormatBytes(bytes), LightingWindow.styles.labelStyle, new GUILayoutOption[0]);
            GUILayout.Label(num != 0 ? string.Empty : "No Lightmaps", LightingWindow.styles.labelStyle, new GUILayoutOption[0]);
            GUILayout.EndVertical();
            GUILayout.EndHorizontal();
            GUILayout.EndVertical();
        }