/// <summary>
/// Allocate each geometry into appropriate tile
/// </summary>
/// <param name="geometries">Dictionary that contains geometries</param>
/// <param name="tiles">Dictionary that contains tiles</param>
/// <param name="maxElementPerTile">Maximum number of elements in each tile</param>
public static void AllocateGeometryToTile(ref Dictionary <string, GeometryStore> geometries, ref Dictionary <XbimRect3D, List <GeometryStore> > tiles, int maxElementPerTile)
{
// allocate element to appropriate tile according to intersect volume
foreach (GeometryStore gs in geometries.Values)
{
XbimRect3D candicateTile = XbimRect3D.Empty;
double intersectVolume = double.MinValue;
foreach (XbimRect3D tile in tiles.Keys)
{
double volume = GeometryStore.Intersect(gs.BoundBox, tile);
if (volume > intersectVolume)
{
candicateTile = tile;
intersectVolume = volume;
}
}
if (!candicateTile.Equals(XbimRect3D.Empty))
{
tiles[candicateTile].Add(gs);
}
}
foreach (XbimRect3D bbox in tiles.Keys.ToList())
{
// remove empty tile
if (tiles[bbox].Count == 0)
{
tiles.Remove(bbox);
}
else if (tiles[bbox].Count > maxElementPerTile && bbox.SizeX > 1 && bbox.SizeY > 1 && bbox.SizeZ > 1) // retile a tile(tile size should be large than 1)
{
Dictionary <XbimRect3D, List <GeometryStore> > subTiles = new Dictionary <XbimRect3D, List <GeometryStore> >();
SplitBoundingBox(bbox, ref subTiles, bbox.SizeX / 2.0, bbox.SizeY / 2.0, bbox.SizeZ / 2.0);
Dictionary <string, GeometryStore> elements = new Dictionary <string, GeometryStore>();
foreach (GeometryStore gs in tiles[bbox])
{
elements.Add(gs.GlobalId, gs);
}
AllocateGeometryToTile(ref elements, ref subTiles, maxElementPerTile);
tiles.Remove(bbox);
foreach (XbimRect3D subBbox in subTiles.Keys)
{
tiles.Add(subBbox, subTiles[subBbox]);
}
}
}
}
/// <summary>
/// Extract Geometries from IFC file.
/// </summary>
/// <param name="model">IfcStore model.</param>
/// <param name="geometries">Geometries data.</param>
/// <param name="modelBoundingBox">Bounding box of the ifc model.</param>
public static void ExtractGeometries(IfcStore model, ref Dictionary <string, GeometryStore> geometries, ref XbimRect3D modelBoundingBox)
{
// context is used to extract geometry data
var context = new Xbim3DModelContext(model);
var meter = context.Model.ModelFactors.OneMeter;
context.CreateContext();
// start to extract geometry data
var instances = context.ShapeInstances();
XbimColourMap colorMap = new XbimColourMap();
foreach (var instance in instances) // each instance is a mesh
{
MeshStore meshStore = new MeshStore();
// get the color of this mesh
var ss = model.Instances[instance.StyleLabel] as IIfcSurfaceStyle;
XbimColour color = XbimColour.DefaultColour;
if (ss != null)
{
var texture = XbimTexture.Create(ss);
color = texture.ColourMap.FirstOrDefault();
}
else
{
var styleId = instance.StyleLabel > 0 ? instance.StyleLabel : instance.IfcTypeId;
var theType = model.Metadata.GetType((short)styleId);
color = colorMap[theType.Name];
}
meshStore.Color = string.Format("{0},{1},{2},{3}", (int)(color.Red * 255), (int)(color.Green * 255), (int)(color.Blue * 255), color.Alpha * 255);
var geometry = context.ShapeGeometry(instance);
var data = (geometry as IXbimShapeGeometryData).ShapeData;
// multiple geometry may belong to one product, like frame and glass belong to a ifcwindow
var product = model.Instances[instance.IfcProductLabel] as IIfcProduct;
if (!geometries.ContainsKey(product.GlobalId))
{
geometries.Add(product.GlobalId, new GeometryStore(product.GlobalId, product.Name));
}
var geometryStore = geometries[product.GlobalId];
// reading the real geometry data
using (var stream = new MemoryStream(data))
{
using (var reader = new BinaryReader(stream))
{
// triangle the instance and transform it to the correct position
var mesh = reader.ReadShapeTriangulation();
mesh = mesh.Transform(instance.Transformation);
// geometry data
var verticesData = new List <double>();
var normalsData = new List <double>();
var indexesData = new List <int>();
// bouding box for instance.
double minX = double.MaxValue, minY = double.MaxValue, minZ = double.MaxValue,
maxX = double.MinValue, maxY = double.MinValue, maxZ = double.MinValue;
var faces = mesh.Faces as List <XbimFaceTriangulation>;
foreach (var face in faces)
{
foreach (var indice in face.Indices)
{
indexesData.Add(indice);
}
foreach (var normal in face.Normals)
{
normalsData.Add(normal.Normal.X);
normalsData.Add(normal.Normal.Y);
normalsData.Add(normal.Normal.Z);
}
}
var vertices = mesh.Vertices as List <XbimPoint3D>;
foreach (var point in vertices)
{
double x = point.X / meter, y = point.Y / meter, z = point.Z / meter;
verticesData.Add(x); // convert to meter
verticesData.Add(y);
verticesData.Add(z);
// update bounding box
minX = Math.Min(minX, x);
minY = Math.Min(minY, y);
minZ = Math.Min(minZ, z);
maxX = Math.Max(maxX, x);
maxY = Math.Max(maxY, y);
maxZ = Math.Max(maxZ, z);
}
if (minX == double.MaxValue || minY == double.MaxValue || minZ == double.MaxValue ||
maxX == double.MinValue || maxY == double.MinValue || maxZ == double.MinValue)
{
throw new Exception("Invalid Boundingbox");
}
// do not trust instance.BoundingBox, it seems to be wrong.
XbimRect3D bbox = new XbimRect3D(minX, minY, minZ, maxX - minX, maxY - minY, maxZ - minZ);
// update boundingbox of current geometryStore
geometryStore.BoundBox = GeometryStore.Union(geometryStore.BoundBox, bbox);
// update boundingbox of ifc model
modelBoundingBox = GeometryStore.Union(modelBoundingBox, bbox);
meshStore.Vertexes = verticesData;
meshStore.Normals = normalsData;
meshStore.Indexes = indexesData;
}
}
geometryStore.Meshes.Add(meshStore);
}
}