/// <summary>
/// Fills solid arrays with data about faces of an object generated whose status is as required
/// </summary>
/// <param name="obj"></param>
/// <param name="vertices"></param>
/// <param name="indices"></param>
/// <param name="faceStatus1"></param>
/// <param name="faceStatus2"></param>
private void GroupObjectComponents(CsgObject3D obj, List <Vertex> vertices, List <int> indices, FaceStatus faceStatus1, FaceStatus faceStatus2)
{
var vertexIndexByHashCode = new Dictionary <Vector3, int>();
//for each face..
foreach (CsgFace face in obj.Faces.All())
{
//if the face status fits with the desired status...
if (face.Status == faceStatus1 || face.Status == faceStatus2)
{
//adds the face elements into the arrays
Vertex[] faceVerts = { face.v1, face.v2, face.v3 };
for (int j = 0; j < faceVerts.Length; j++)
{
if (vertexIndexByHashCode.ContainsKey(faceVerts[j].Position))
{
indices.Add(vertexIndexByHashCode[faceVerts[j].Position]);
}
else
{
vertexIndexByHashCode.Add(faceVerts[j].Position, vertices.Count);
indices.Add(vertices.Count);
vertices.Add(faceVerts[j]);
}
}
}
}
}
/// <summary>
/// Classify faces as being inside, outside or on boundary of other object
/// </summary>
/// <param name="otherObject">object 3d used for the comparison</param>
public void ClassifyFaces(CsgObject3D otherObject, CancellationToken cancellationToken, Action <CsgFace> classifyFaces = null)
{
var otherBounds = otherObject.Bounds;
foreach (var vertex in vertices)
{
cancellationToken.ThrowIfCancellationRequested();
if (!otherBounds.Contains(vertex.Position) &&
vertex.Status != FaceStatus.Outside)
{
vertex.Status = FaceStatus.Outside;
}
}
//calculate adjacency information
Faces.All();
foreach (var face in Faces.QueryResults)
{
cancellationToken.ThrowIfCancellationRequested();
face.v1.AddAdjacentVertex(face.v2);
face.v1.AddAdjacentVertex(face.v3);
face.v2.AddAdjacentVertex(face.v1);
face.v2.AddAdjacentVertex(face.v3);
face.v3.AddAdjacentVertex(face.v1);
face.v3.AddAdjacentVertex(face.v2);
}
// for each face
foreach (var face in Faces.QueryResults)
{
cancellationToken.ThrowIfCancellationRequested();
// If the face vertices can't be classified with the simple classify
if (face.SimpleClassify() == false)
{
//makes the ray trace classification
face.RayTraceClassify(otherObject);
//mark the vertices
if (face.v1.Status == FaceStatus.Unknown)
{
face.v1.Mark(face.Status);
}
if (face.v2.Status == FaceStatus.Unknown)
{
face.v2.Mark(face.Status);
}
if (face.v3.Status == FaceStatus.Unknown)
{
face.v3.Mark(face.Status);
}
}
classifyFaces?.Invoke(face);
}
}
public BooleanModeller(Solid solid1, Solid solid2, Action <string, double> reporter, CancellationToken cancellationToken)
{
this.reporter = reporter;
this.cancellationToken = cancellationToken;
//representation to apply boolean operations
reporter?.Invoke("Create Csg Object 1", 0.1);
object1 = new CsgObject3D(solid1);
reporter?.Invoke("Create Csg Object 2", 0.2);
object2 = new CsgObject3D(solid2);
object1Copy = new CsgObject3D(solid1);
}
private void PrepareData()
{
if (object1Copy != null)
{
//split the faces so that none of them intercepts each other
reporter?.Invoke("Split Faces 1", 0.4);
object1.SplitFaces(object2, cancellationToken, Object1SplitFace, Object1SplitResults);
reporter?.Invoke("Split Faces 2", 0.6);
object2.SplitFaces(object1Copy, cancellationToken, Object2SplitFace, Object2SplitResults);
// free the memory
object1Copy = null;
//classify faces as being inside or outside the other solid
reporter?.Invoke("Classify Faces 1", 0.8);
object1.ClassifyFaces(object2, Object1ClassifyFace);
reporter?.Invoke("Classify Faces 2", 0.9);
object2.ClassifyFaces(object1, Object2ClassifyFace);
}
}
/// <summary>
/// Split faces so that no face is intercepted by a face of other object
/// </summary>
/// <param name="compareObject">the other object 3d used to make the split</param>
public void SplitFaces(CsgObject3D compareObject, CancellationToken cancellationToken,
Action <CsgFace, CsgFace> splitFaces = null,
Action <List <CsgFace> > results = null)
{
Stack <CsgFace> newFacesFromSplitting = new Stack <CsgFace>();
int numFacesStart = this.Faces.Count;
//if the objects bounds overlap...
//for each object1 face...
var bounds = compareObject.GetBound();
Faces.SearchBounds(bounds);
foreach (var thisFaceIn in Faces.QueryResults) // put it in an array as we will be adding new faces to it
{
newFacesFromSplitting.Push(thisFaceIn);
// make sure we process every face that we have added during splitting before moving on to the next face
while (newFacesFromSplitting.Count > 0)
{
var faceToSplit = newFacesFromSplitting.Pop();
// stop processing if operation has been canceled
cancellationToken.ThrowIfCancellationRequested();
//if object1 face bound and object2 bound overlap ...
//for each object2 face...
compareObject.Faces.SearchBounds(faceToSplit.GetBound());
foreach (var cuttingFace in compareObject.Faces.QueryResults)
{
//if object1 face bound and object2 face bound overlap...
//PART I - DO TWO POLIGONS INTERSECT?
//POSSIBLE RESULTS: INTERSECT, NOT_INTERSECT, COPLANAR
//distance from the face1 vertices to the face2 plane
double v1DistToCuttingFace = cuttingFace.DistanceFromPlane(faceToSplit.v1);
double v2DistToCuttingFace = cuttingFace.DistanceFromPlane(faceToSplit.v2);
double v3DistToCuttingFace = cuttingFace.DistanceFromPlane(faceToSplit.v3);
//distances signs from the face1 vertices to the face2 plane
PlaneSide sideFace1Vert1 = (v1DistToCuttingFace > EqualityTolerance ? PlaneSide.Front : (v1DistToCuttingFace < -EqualityTolerance ? PlaneSide.Back : PlaneSide.On));
PlaneSide sideFace1Vert2 = (v2DistToCuttingFace > EqualityTolerance ? PlaneSide.Front : (v2DistToCuttingFace < -EqualityTolerance ? PlaneSide.Back : PlaneSide.On));
PlaneSide sideFace1Vert3 = (v3DistToCuttingFace > EqualityTolerance ? PlaneSide.Front : (v3DistToCuttingFace < -EqualityTolerance ? PlaneSide.Back : PlaneSide.On));
//if all the signs are zero, the planes are coplanar
//if all the signs are positive or negative, the planes do not intersect
//if the signs are not equal...
if (!(sideFace1Vert1 == sideFace1Vert2 && sideFace1Vert2 == sideFace1Vert3))
{
//distance from the face2 vertices to the face1 plane
double faceToSplitTo1 = faceToSplit.DistanceFromPlane(cuttingFace.v1);
double faceToSplitTo2 = faceToSplit.DistanceFromPlane(cuttingFace.v2);
double faceToSplitTo3 = faceToSplit.DistanceFromPlane(cuttingFace.v3);
//distances signs from the face2 vertices to the face1 plane
PlaneSide signFace2Vert1 = (faceToSplitTo1 > EqualityTolerance ? PlaneSide.Front : (faceToSplitTo1 < -EqualityTolerance ? PlaneSide.Back : PlaneSide.On));
PlaneSide signFace2Vert2 = (faceToSplitTo2 > EqualityTolerance ? PlaneSide.Front : (faceToSplitTo2 < -EqualityTolerance ? PlaneSide.Back : PlaneSide.On));
PlaneSide signFace2Vert3 = (faceToSplitTo3 > EqualityTolerance ? PlaneSide.Front : (faceToSplitTo3 < -EqualityTolerance ? PlaneSide.Back : PlaneSide.On));
//if the signs are not equal...
if (!(signFace2Vert1 == signFace2Vert2 && signFace2Vert2 == signFace2Vert3))
{
var line = new Line(faceToSplit, cuttingFace);
//intersection of the face1 and the plane of face2
var segment1 = new Segment(line, faceToSplit, sideFace1Vert1, sideFace1Vert2, sideFace1Vert3);
//intersection of the face2 and the plane of face1
var segment2 = new Segment(line, cuttingFace, signFace2Vert1, signFace2Vert2, signFace2Vert3);
//if the two segments intersect...
if (segment1.Intersect(segment2))
{
//PART II - SUBDIVIDING NON-COPLANAR POLYGONS
Stack <CsgFace> facesFromSplit = new Stack <CsgFace>();
if (this.SplitFace(faceToSplit, segment1, segment2, facesFromSplit) &&
facesFromSplit.Count > 0 &&
!(facesFromSplit.Count == 1 && facesFromSplit.Peek().Equals(faceToSplit)))
{
foreach (var face in facesFromSplit)
{
newFacesFromSplitting.Push(face);
}
// send debugging information if registered
splitFaces?.Invoke(faceToSplit, cuttingFace);
results?.Invoke(facesFromSplit.ToList());
break;
}
}
}
}
}
}
}
}
/// <summary>
/// Classifies the face based on the ray trace technique
/// </summary>
/// <param name="obj">object3d used to compute the face status</param>
public void RayTraceClassify(CsgObject3D obj)
{
var random = new Random();
//creating a ray starting at the face baricenter going to the normal direction
Ray ray = new Ray(center, Normal);
//Line ray = new Line(GetNormal(), center);
ray.PerturbDirection(random);
bool success;
double distance;
Vector3 intersectionPoint;
CsgFace closestFace = null;
double closestDistance;
do
{
success = true;
closestDistance = Double.MaxValue;
//for each face from the other solid...
//foreach (Face face in obj.Faces.AllObjects())
obj.Faces.AlongRay(ray);
foreach (var face in obj.Faces.QueryResults)
{
double hitDistance;
bool front;
//if ray intersects the plane...
if (face.Plane.RayHitPlane(ray, out hitDistance, out front))
{
double dotProduct = Vector3.Dot(face.Normal, ray.directionNormal);
distance = hitDistance;
intersectionPoint = ray.origin + ray.directionNormal * hitDistance;
ray.maxDistanceToConsider = hitDistance;
//if ray lies in plane...
if (Math.Abs(distance) < EqualityTolerance && Math.Abs(dotProduct) < EqualityTolerance)
{
//disturb the ray in order to not lie into another plane
ray.PerturbDirection(random);
success = false;
break;
}
//if ray starts in plane...
if (Math.Abs(distance) < EqualityTolerance && Math.Abs(dotProduct) > EqualityTolerance)
{
//if ray intersects the face...
if (face.ContainsPoint(intersectionPoint))
{
//faces coincide
closestFace = face;
closestDistance = 0;
break;
}
}
//if ray intersects plane...
else if (Math.Abs(dotProduct) > EqualityTolerance && distance > EqualityTolerance)
{
if (distance < closestDistance)
{
//if ray intersects the face;
if (face.ContainsPoint(intersectionPoint))
{
//this face is the closest face until now
closestDistance = distance;
closestFace = face;
}
}
}
}
}
} while (success == false);
if (closestFace == null)
{
//none face found: outside face
Status = FaceStatus.Outside;
}
else //face found: test dot product
{
double dotProduct = Vector3.Dot(closestFace.Normal, ray.directionNormal);
//distance = 0: coplanar faces
if (Math.Abs(closestDistance) < EqualityTolerance)
{
if (dotProduct > EqualityTolerance)
{
Status = FaceStatus.Same;
}
else if (dotProduct < -EqualityTolerance)
{
Status = FaceStatus.Opposite;
}
}
else if (dotProduct > EqualityTolerance)
{
//dot product > 0 (same direction): inside face
Status = FaceStatus.Inside;
}
else if (dotProduct < -EqualityTolerance)
{
//dot product < 0 (opposite direction): outside face
Status = FaceStatus.Outside;
}
}
}