/// <summary>
        /// Loads VertexGeometry from aara files. Beware: add Local2Global node for global space.
        /// </summary>
        /// <param name="positions">Raw positions, read from aara files for possible further processing.</param>
        /// <param name="dataType">DataType of positions.</param>
        /// <returns>Vertex Geometry in local OPC space.</returns>
        public static VertexGeometry LoadPatch(PatchFileInfo info, string basePath, PositionsType posType, out Array positions, out Symbol dataType,
                                               bool loadNormals = true, bool loadTexCoords = true, bool loadDiffTex = true, bool loadHueTex = true, float maxTriangleSize = float.PositiveInfinity, bool loadAsDoubles = false)
        {
            var vg = new VertexGeometry(GeometryMode.TriangleList);

            positions = null;

            // load metadata
            var aara3dPos = AaraData.FromFile(
                Path.Combine(basePath, posType == PositionsType.V3dPositions
                ? info.Positions : info.Positions2d));

            dataType = aara3dPos.DataTypeAsSymbol;

            var resolution = new V2i(aara3dPos.Size);

            if (resolution.AnySmaller(2))
            {
                Report.Warn("ignoring patch {0} due to invalid gridresolution {1}", basePath, resolution);
                return(null);
            }

            // load positions
            positions = aara3dPos.LoadElements();
            var positions3d = loadAsDoubles ? positions : AaraData.ConvertArrayToV3fs[aara3dPos.DataTypeAsSymbol](positions);

            //var positionsV3 = loadAsDoubles ?
            //    (Array)AaraData.ConvertArrayToV3ds[aara3dPos.DataTypeAsSymbol](positions) :
            //    (Array);

            vg.Positions = positions3d;

            var p = AaraData.ConvertArrayToV3fs[aara3dPos.DataTypeAsSymbol](positions);

            // calculate indices
            var invalidPoints = OpcIndices.GetInvalidPositions(p);

            // limit triangle size
            if ((maxTriangleSize < float.PositiveInfinity) && (maxTriangleSize > 0.000001f))
            {
                vg.Indices = OpcIndices.ComputeIndexArray(resolution, invalidPoints.ToList(), p, maxTriangleSize);
            }
            else
            {
                vg.Indices = OpcIndices.ComputeIndexArray(resolution, invalidPoints.ToList());
            }

            // load normals
            if (loadNormals)
            {
                var normalPath = Path.Combine(basePath, "Normals.aara");
                if (StorageConfig.FileExists(normalPath))
                {
                    var normals   = AaraData.FromFile(normalPath);
                    var normals3d = AaraData.ConvertArrayToV3fs[normals.DataTypeAsSymbol](normals.LoadElements());
                    vg.Normals = normals3d;
                }
            }

            // load coordinates
            vg.Coordinates = new CoordinatesMap();
            if (loadTexCoords)
            {
                var coordPath   = Path.Combine(basePath, info.Coordinates.First());
                var coordinates = AaraData.FromFile(coordPath).LoadElements() as V2f[];
                vg.Coordinates[VertexGeometry.Property.DiffuseColorCoordinates] = coordinates;
            }

            // load textures
            vg.Textures = new TexturesMap();
            if (loadDiffTex)
            {
                var texFile = Path.ChangeExtension(info.Textures.First(), ".dds");
                var texPath = Path.GetFullPath(Path.Combine(basePath, @"..\..\images", texFile));

                if (StorageConfig.FileExists(texPath))
                {
                    var img = Convertible.FromFile(texPath);

                    vg.Textures[VertexGeometry.Property.DiffuseColorTexture] =
                        new Aardvark.Rendering.Texture(img)
                    {
                        ForceImmediateUpload = false
                    };
                }
            }
            if (loadHueTex)
            {
                vg.Textures[VertexGeometry.Property.LightMapTexture] =
                    new Aardvark.Rendering.Texture(Resources.HueColorMap.Convertible());
            }

            return(vg);
        }