/// <summary>
/// Determines if a cell is on the edges of a cell collections
/// </summary>
/// <param name="cellID">The ID of the cell</param>
/// <param name="cellularFloor">The CellularFloorBaseGeometry to which this cell belongs</param>
/// <param name="collection">Cell ID collection</param>
/// <returns>true for being on the edge false for not being on the edge</returns>
private static bool onEdge(int cellID, CellularFloorBaseGeometry cellularFloor, HashSet <int> collection)
{
var index = cellularFloor.FindIndex(cellID);
if (index.I == 0 || index.I == cellularFloor.GridWidth - 1 || index.J == 0 || index.J == cellularFloor.GridHeight - 1)
{
return(true);
}
int iMin = (index.I == 0) ? 0 : index.I - 1;
int iMax = (index.I == cellularFloor.GridWidth - 1) ? cellularFloor.GridWidth - 1 : index.I + 1;
int jMin = (index.J == 0) ? 0 : index.J - 1;
int jMax = (index.J == cellularFloor.GridHeight - 1) ? cellularFloor.GridHeight - 1 : index.J + 1;
for (int i = iMin; i <= iMax; i++)
{
for (int j = jMin; j <= jMax; j++)
{
if (cellularFloor.ContainsCell(i, j))
{
if (!collection.Contains(cellularFloor.Cells[i, j].ID))
{
return(true);
}
}
}
}
return(false);
}
/// <summary>
/// Determines if a cell is on the edges of a cell collections
/// </summary>
/// <param name="index">The index of the cell</param>
/// <param name="cellularFloor">The CellularFloorBaseGeometry to which this cell belongs</param>
/// <param name="collection">Cell ID collection</param>
/// <returns>true for being on the edge false for not being on the edge</returns>
private static bool onEdge(Index index, CellularFloorBaseGeometry cellularFloor, HashSet <Cell> collection)
{
foreach (Index item in Index.Neighbors)
{
Index neighbor = item + index;
if (cellularFloor.ContainsCell(neighbor))
{
if (!collection.Contains(cellularFloor.Cells[neighbor.I, neighbor.J]))
{
return(true);
}
}
}
return(false);
}
/// <summary>
/// Checks the existence of a line of sight between two points.
/// </summary>
/// <param name="origin">The origin.</param>
/// <param name="target">The target.</param>
/// <param name="barrierType">Type of the barrier.</param>
/// <param name="cellularFloor">The cellular floor.</param>
/// <param name="tolerance">The tolerance.</param>
/// <returns><c>true</c> if visible, <c>false</c> otherwise.</returns>
public static bool Visible(UV origin, UV target, BarrierType barrierType, CellularFloorBaseGeometry cellularFloor, double tolerance = OSMDocument.AbsoluteTolerance)
{
UV direction = target - origin;
double length = direction.GetLength();
direction /= length;
Ray ray = new Ray(origin, direction, cellularFloor.Origin,
cellularFloor.CellSize, tolerance);
while (ray.Length + tolerance < length)
{
Index index = ray.NextIndex(cellularFloor.FindIndex, tolerance);
if (cellularFloor.ContainsCell(index))
{
switch (barrierType)
{
case BarrierType.Visual:
if (cellularFloor.Cells[index.I, index.J].VisualOverlapState == OverlapState.Overlap)
{
foreach (int item in cellularFloor.Cells[index.I, index.J].VisualBarrierEdgeIndices)
{
double?distance = ray.DistanceToForIsovist(cellularFloor.VisualBarrierEdges[item], tolerance);
if (distance != null && distance.Value + tolerance < length)
{
UVLine hitEdge = cellularFloor.VisualBarrierEdges[item];
return(false);
}
}
}
break;
case BarrierType.Physical:
if (cellularFloor.Cells[index.I, index.J].PhysicalOverlapState == OverlapState.Overlap)
{
foreach (int item in cellularFloor.Cells[index.I, index.J].PhysicalBarrierEdgeIndices)
{
double?distance = ray.DistanceToForIsovist(cellularFloor.PhysicalBarrierEdges[item], tolerance);
if (distance != null && distance.Value + tolerance < length)
{
UVLine hitEdge = cellularFloor.PhysicalBarrierEdges[item];
return(false);
}
}
}
break;
case BarrierType.Field:
if (cellularFloor.Cells[index.I, index.J].FieldOverlapState == OverlapState.Overlap)
{
foreach (int item in cellularFloor.Cells[index.I, index.J].FieldBarrierEdgeIndices)
{
double?distance = ray.DistanceToForIsovist(cellularFloor.FieldBarrierEdges[item], tolerance);
if (distance != null && distance.Value + tolerance < length)
{
UVLine hitEdge = cellularFloor.FieldBarrierEdges[item];
return(false);
}
}
}
break;
default:
break;
}
}
}
return(true);
}
