/// <summary>
/// Gets the set of floating objects within a given prism.
/// Both objects used and unused in this simulation step are considered.
/// </summary>
public FloatingObjectsSet GetObjectsInPrism(Polygon3D basePolygon, Vector3D vector)
{
FloatingObjectsSet insideObjects = new FloatingObjectsSet();
var topPolygon = basePolygon.Select(vertex => vertex + vector);
foreach (var key in KeysInBox(new Box3D(basePolygon.Union(topPolygon))))
{
insideObjects.UnionWith(v_Grid[key].OldSet.GetHashSet().Where(fltObject =>
basePolygon.IntersectsWith(fltObject.Position, fltObject.Position - vector)));
insideObjects.UnionWith(v_Grid[key].NewSet.GetHashSet().Where(fltObject =>
basePolygon.IntersectsWith(fltObject.Position, fltObject.Position - vector)));
}
return(insideObjects);
}
/// <summary>
/// True if (a) both polygons lie in the same plane (vertical distance up to Msystem.Tolerance), and
/// (b) they overlap (the overlapping horizontal distance exceeds Msystem.Tolerance)
/// </summary>
public bool OverlapsWith(Polygon3D another)
{
if (!(Normal.IsParallelTo(another.Normal) &&
Plane.AbsoluteDistanceTo(another[0]) < MSystem.Tolerance))
{
return(false);
}
// If one polygon contains inside a vertex of another, then they overlap
// Border tolerance is allowed for case that they just touch (do not overlap)
if (another.Any(t => ContainsPoint(t, MSystem.Tolerance)) ||
this.Any(t => another.ContainsPoint(t, MSystem.Tolerance)))
{
return(true);
}
// Now check the case when no vertex of one polygon lies inside another
var intersections = new HashSet <Point3D>();
foreach (var edge1 in Edges)
{
foreach (var edge2 in another.Edges)
{
var intersection = edge1.ClosestPointsBetween(edge2, true);
if (intersection.Item1.DistanceTo(intersection.Item2) < MSystem.Tolerance)
{
intersections.Add(intersection.Item1);
}
}
}
if (!intersections.Any())
{
return(false);
}
// Again exclude the case when they just touch and do not overlap
var c = Point3D.Centroid(intersections);
return(ContainsPoint(c, MSystem.Tolerance) || another.ContainsPoint(c, MSystem.Tolerance));
}
/// <summary>
/// Calculates possible pushing of "another" polytope by this segment being itself
/// pushed by "pushingVector" which MAY cause its intersection with "another".
/// If this segment already intersects "another", "pushingVector" is returned.
/// </summary>
/// <param name="another">The vertices of object to be eventually pushed.</param>
/// <param name="pushingVector">Pushing vector of this object.</param>
/// <returns>Pushing vector of another object.</returns>
public Vector3D PushingOf(IPolytope another, Vector3D pushingVector)
{
Polygon3D polygon = another as Polygon3D;
if (polygon == null || pushingVector.Length < MSystem.Tolerance) // length must be tested, otherwise the Polygon3D ctor may throw an exception
{
return(default(Vector3D));
}
if (this.Vector.IsParallelTo(pushingVector))
{
var intersection0 = polygon.IntersectionWith(this[0], this[0] + pushingVector);
var intersection1 = polygon.IntersectionWith(this[1], this[1] + pushingVector);
var vector0 = intersection0.IsNaN() ? pushingVector : intersection0 - this[0];
var vector1 = intersection1.IsNaN() ? pushingVector : intersection1 - this[1];
// Get minimal vector from this segment to the intersection point
var minVector = vector0.Length > vector1.Length ? vector1 : vector0;
return(pushingVector - minVector);
}
var projectionFace = new Polygon3D(new List <Point3D> {
this[0], this[1], this[1] + pushingVector, this[0] + pushingVector
},
Name + "-pushing projection");
double pLength = pushingVector.Length, distance = pLength;
foreach (var point in polygon.IntersectionsWith(projectionFace))
{
distance = Math.Min(distance, point.DistanceTo(
Edges[0].ClosestPointsBetween(new Line3D(point, point - pushingVector), true).Item2));
}
return(pushingVector.ScaleBy((pLength - distance) / pLength));
}
/// <summary>
/// Gives the reference point close to a given position around which we search for / add / remove floating objects
/// inside/outside this object. If the object is not 2D, the first argument is returned.
/// </summary>
/// <param name="position">Position on tiles (typically of connector or protein)</param>
/// <param name="side">Side of the tile</param>
/// <returns>Reference point corresponding to "inside"/"outside" parameter</returns>
public Point3D SidePoint(Point3D position, Tile.SideType side)
{
Polygon3D polygon = Vertices as Polygon3D;
return(polygon?.SidePoint(position, side) ?? position);
}