private IReadOnlyList <IConfigurableFacade> CreateExternalFacades(Prism bounds, IFloorPlan plan)
{
var externalSections = new List <IConfigurableFacade>();
//Find the parent building which contains this floor
var building = this.SearchUp <IBuilding, IBuilding>(n => n, typeof(IBuildingContainer));
if (building == null)
{
throw new InvalidOperationException("Attempted to subdivide BaseFloor, but cannot find IBuilding node ancestor");
}
//Get all facades which cross this floor
var facades = building.Facades(FloorIndex);
for (var i = 0; i < plan.ExternalFootprint.Count; i++)
{
//Nb. There's lots of "WS" going on here, this stands for "World Space"
//We have the footprint in floor space and the facades in facade space, we transform both into world space to compare them
//Get start and end points of this edge
var start = plan.ExternalFootprint[i];
var end = plan.ExternalFootprint[(i + 1) % plan.ExternalFootprint.Count];
var footprintSegWS = new LineSegment2(start, end).Transform(WorldTransformation);
var footprintLineWS = footprintSegWS.Line;
//Select the exteral facade which lies along this edge
var wall = (from facade in facades
let facadeSegWS = facade.Section.ExternalLineSegment.Transform(facade.WorldTransformation)
let facadeLineWS = facadeSegWS.Line
where facadeLineWS.Parallelism(footprintLineWS) != Parallelism.None
let aD = footprintSegWS.DistanceToPoint(facadeSegWS.Start)
let bD = footprintSegWS.DistanceToPoint(facadeSegWS.End)
orderby aD + bD
select facade).FirstOrDefault();
//If we didn't find a parallel external facade then just give up!
if (wall == null)
{
continue;
}
//Start and end points (X-Axis) are always start and end of facade (i.e. subsection is always full width)
//What are the start and end points (Y-Axis)
var bottomOfFacade = building.Floor(wall.BottomFloorIndex).FloorAltitude;
var y = FloorAltitude - bottomOfFacade - _floorThickness - wall.Bounds.Height / 2;
//Height of the open space of the floor (top of floor, to bottom of ceiling)
var height = Bounds.Height - _floorThickness - _ceilingThickness;
//how wide is the wall?
var wallLength = wall.Section.ExternalLineSegment.LongLine.Direction.Length();
var subsection = new SubsectionFacade(wall,
new Vector2(-wallLength, y),
new Vector2(wallLength, y + height),
0, 1,
wall.Section
);
externalSections.Add(subsection);
}
return(externalSections);
}