/**
* Fills solid arrays with data about faces of an object generated whose status
* is as required
*
* @param object3d solid object used to fill the arrays
* @param vertices vertices array to be filled
* @param indices indices array to be filled
* @param faceStatus1 a status expected for the faces used to to fill the data arrays
* @param faceStatus2 a status expected for the faces used to to fill the data arrays
*/
private void GroupObjectComponents(Object3D obj, List <Vertex> vertices, List <int> indices, Status faceStatus1, Status faceStatus2)
{
Face face;
//for each face..
for (int i = 0; i < obj.NumFaces; i++)
{
face = obj.GetFace(i);
//if the face status fits with the desired status...
if (face.GetStatus() == faceStatus1 || face.GetStatus() == 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 (vertices.Contains(faceVerts[j]))
{
indices.Add(vertices.IndexOf(faceVerts[j]));
}
else
{
indices.Add(vertices.Count);
vertices.Add(faceVerts[j]);
}
}
}
}
}
/// <summary>
/// 按特定条件选取物件中适合的三角面填充入容器
/// </summary>
/// <param name="obj">选取面的物体</param>
/// <param name="vertices">存放选取的顶点</param>
/// <param name="indices">存放选取的三角形序号</param>
/// <param name="faceStatus1">第一个筛选条件</param>
/// <param name="faceStatus2">第二个筛选条件</param>
private void GroupObjectComponents(Object3D obj, List <Vertex> vertices, List <int> indices, Status faceStatus1, Status faceStatus2)
{
using (var faceVs = CollectionPool <Vertex> .ListCell.Create(3))
{
for (int faceCount = 0; faceCount < obj.GetNumFaces(); faceCount++)
{
var face = obj.GetFace(faceCount);
if (face.Status == faceStatus1 || face.Status == faceStatus2) // if the face status fits with the desired status...
{
faceVs[0] = face.v1;
faceVs[1] = face.v2;
faceVs[2] = face.v3;
for (int triIndex = 0; triIndex < 3; triIndex++)
{
if (vertices.Contains(faceVs[triIndex]))
{
indices.Add(vertices.IndexOf(faceVs[triIndex]));
}
else
{
indices.Add(vertices.Count);
vertices.Add(faceVs[triIndex]);
}
}
}
}
}
}
/// <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(Object3D obj)
{
//creating a ray starting at the face baricenter going to the normal direction
Line ray = new Line(GetNormal(), center);
bool success;
double distance;
Vector3 intersectionPoint;
Face closestFace = null;
double closestDistance;
do
{
success = true;
closestDistance = Double.MaxValue;
//for each face from the other solid...
for (int faceIndex = 0; faceIndex < obj.GetNumFaces(); faceIndex++)
{
Face face = obj.GetFace(faceIndex);
intersectionPoint = ray.ComputePlaneIntersection(face.GetPlane());
//if ray intersects the plane...
if (intersectionPoint.x != double.PositiveInfinity)
{
double dotProduct = Vector3.Dot(face.GetNormal(), ray.Direction);
distance = ray.ComputePointToPointDistance(intersectionPoint);
//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();
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 = Status.OUTSIDE;
}
else //face found: test dot product
{
double dotProduct = Vector3.Dot(closestFace.GetNormal(), ray.Direction);
//distance = 0: coplanar faces
if (Math.Abs(closestDistance) < EqualityTolerance)
{
if (dotProduct > EqualityTolerance)
{
status = Status.SAME;
}
else if (dotProduct < -EqualityTolerance)
{
status = Status.OPPOSITE;
}
}
else if (dotProduct > EqualityTolerance)
{
//dot product > 0 (same direction): inside face
status = Status.INSIDE;
}
else if (dotProduct < -EqualityTolerance)
{
//dot product < 0 (opposite direction): outside face
status = Status.OUTSIDE;
}
}
}
/// <summary>
/// Split faces so that none 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(Object3D compareObject)
{
Line line;
Face thisFace, compareFace;
Segment segment1;
Segment segment2;
double v1DistToCompareFace, distFace1Vert2, distFace1Vert3, distFace2Vert1, distFace2Vert2, distFace2Vert3;
int signFace1Vert1, signFace1Vert2, signFace1Vert3, signFace2Vert1, signFace2Vert2, signFace2Vert3;
int numFacesBefore = this.GetNumFaces();
int numFacesStart = this.GetNumFaces();
//if the objects bounds overlap...
if (this.GetBound().Overlap(compareObject.GetBound()))
{
//for each object1 face...
for (int thisFaceIndex = 0; thisFaceIndex < this.GetNumFaces(); thisFaceIndex++)
{
//if object1 face bound and object2 bound overlap ...
thisFace = GetFace(thisFaceIndex);
if (thisFace.GetBound().Overlap(compareObject.GetBound()))
{
//for each object2 face...
for (int compareFaceIndex = 0; compareFaceIndex < compareObject.GetNumFaces(); compareFaceIndex++)
{
//if object1 face bound and object2 face bound overlap...
compareFace = compareObject.GetFace(compareFaceIndex);
if (thisFace.GetBound().Overlap(compareFace.GetBound()))
{
//PART I - DO TWO POLIGONS INTERSECT?
//POSSIBLE RESULTS: INTERSECT, NOT_INTERSECT, COPLANAR
//distance from the face1 vertices to the face2 plane
v1DistToCompareFace = ComputeDistance(thisFace.v1, compareFace);
distFace1Vert2 = ComputeDistance(thisFace.v2, compareFace);
distFace1Vert3 = ComputeDistance(thisFace.v3, compareFace);
//distances signs from the face1 vertices to the face2 plane
signFace1Vert1 = (v1DistToCompareFace > EqualityTolerance ? 1 : (v1DistToCompareFace < -EqualityTolerance ? -1 : 0));
signFace1Vert2 = (distFace1Vert2 > EqualityTolerance ? 1 : (distFace1Vert2 < -EqualityTolerance ? -1 : 0));
signFace1Vert3 = (distFace1Vert3 > EqualityTolerance ? 1 : (distFace1Vert3 < -EqualityTolerance ? -1 : 0));
//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 (!(signFace1Vert1 == signFace1Vert2 && signFace1Vert2 == signFace1Vert3))
{
//distance from the face2 vertices to the face1 plane
distFace2Vert1 = ComputeDistance(compareFace.v1, thisFace);
distFace2Vert2 = ComputeDistance(compareFace.v2, thisFace);
distFace2Vert3 = ComputeDistance(compareFace.v3, thisFace);
//distances signs from the face2 vertices to the face1 plane
signFace2Vert1 = (distFace2Vert1 > EqualityTolerance ? 1 : (distFace2Vert1 < -EqualityTolerance ? -1 : 0));
signFace2Vert2 = (distFace2Vert2 > EqualityTolerance ? 1 : (distFace2Vert2 < -EqualityTolerance ? -1 : 0));
signFace2Vert3 = (distFace2Vert3 > EqualityTolerance ? 1 : (distFace2Vert3 < -EqualityTolerance ? -1 : 0));
//if the signs are not equal...
if (!(signFace2Vert1 == signFace2Vert2 && signFace2Vert2 == signFace2Vert3))
{
line = new Line(thisFace, compareFace);
//intersection of the face1 and the plane of face2
segment1 = new Segment(line, thisFace, signFace1Vert1, signFace1Vert2, signFace1Vert3);
//intersection of the face2 and the plane of face1
segment2 = new Segment(line, compareFace, signFace2Vert1, signFace2Vert2, signFace2Vert3);
//if the two segments intersect...
if (segment1.Intersect(segment2))
{
//PART II - SUBDIVIDING NON-COPLANAR POLYGONS
int lastNumFaces = GetNumFaces();
bool splitOccured = this.SplitFace(thisFaceIndex, segment1, segment2);
//prevent from infinite loop (with a loss of faces...)
if (GetNumFaces() > numFacesStart * 100)
{
//System.out.println("possible infinite loop situation: terminating faces split");
//return;
int a = 0;
}
//if the face in the position isn't the same, there was a break
if (splitOccured &&
thisFace != GetFace(thisFaceIndex))
{
//if the generated solid is equal the origin...
if (thisFace.Equals(GetFace(GetNumFaces() - 1)))
{
//return it to its position and jump it
if (thisFaceIndex != (GetNumFaces() - 1))
{
faces.RemoveAt(GetNumFaces() - 1);
faces.Insert(thisFaceIndex, thisFace);
}
else
{
continue;
}
}
//else: test next face
else
{
thisFaceIndex--;
break;
}
}
}
}
}
}
}
}
}
}
}
/// <summary>
/// 为表面分类，基于光线追踪技术
/// </summary>
/// <param name="obj">计算面状态的 3D 物件</param>
public void RayTraceClassify(Object3D obj)
{
Line ray = new Line(PlaneNormal, Center); // 射线从面的几何中心发出，方向为法线方向
Face closet = default;
bool foundCloset = false;
double closestDistance;
bool success;
do
{
success = true;
closestDistance = double.MaxValue;
for (int faceIndex = 0; faceIndex < obj.GetNumFaces(); faceIndex++)
{
Face face = obj.GetFace(faceIndex);
var intersectionPoint = ray.ComputePlaneIntersection(face.Plane); // 对三角面所在的平面采样
if (intersectionPoint.x < float.PositiveInfinity) // 射线被平面拦截
{
var distance = ray.ComputePointToPointDistance(intersectionPoint);
var dot = Vector3Double.Dot(face.PlaneNormal, ray.Direction);
bool parallel = Math.Abs(dot) < epsilon; // 射线与平面平行
//if ray lies in plane...
if (Math.Abs(distance) < epsilon) // 交点是射线起点
{
if (parallel)
{
// 略微抖动光线方向以免采样到另一平面
ray.PerturbDirection();
success = false;
break;
}
else if (face.ContainsPoint(intersectionPoint))
{
// 面重合
closet = face;
foundCloset = true;
closestDistance = 0;
break;
}
}
else if (!parallel && distance > epsilon) // 射线产生交点
{
if (distance < closestDistance && face.ContainsPoint(intersectionPoint))
{
closestDistance = distance;
closet = face; // 当前的面时最近的平面
foundCloset = true;
}
}
}
}
} while (!success);
if (!foundCloset)
{
Status = Status.OUTSIDE;
} // 没有找到面，自己是外部面
else // 由离自己最近的面，检查方向
{
var dot = Vector3Double.Dot(closet.PlaneNormal, ray.Direction);
if (Math.Abs(closestDistance) < epsilon) // 距离为零，这个面和自己重合
{
if (dot > epsilon)
{
Status = Status.SAME;
}
else if (dot < -epsilon)
{
Status = Status.OPPOSITE;
}
}
else if (dot > epsilon)
{
Status = Status.INSIDE;
} // 不重合，同向，在参数物件内部
else if (dot < -epsilon)
{
Status = Status.OUTSIDE;
} // 不重合，反向，在参数物件外部
}
}
/// <summary>
/// Split faces so that none face is intercepted by a face of other object
/// </summary>
/// <param name="obj">the other object 3d used to make the split</param>
public void SplitFaces(Object3D obj)
{
Line line;
Face face1, face2;
Segment segment1;
Segment segment2;
double distFace1Vert1, distFace1Vert2, distFace1Vert3, distFace2Vert1, distFace2Vert2, distFace2Vert3;
int signFace1Vert1, signFace1Vert2, signFace1Vert3, signFace2Vert1, signFace2Vert2, signFace2Vert3;
int numFacesBefore = NumFaces;
int numFacesStart = NumFaces;
//if the objects bounds overlap...
if (_Bound.Overlap(obj._Bound))
{
//for each object1 face...
for (int i = 0; i < NumFaces; i++)
{
//if object1 face bound and object2 bound overlap ...
face1 = GetFace(i);
if (face1.GetBound().Overlap(obj._Bound))
{
//for each object2 face...
for (int j = 0; j < obj.NumFaces; j++)
{
//if object1 face bound and object2 face bound overlap...
face2 = obj.GetFace(j);
if (face1.GetBound().Overlap(face2.GetBound()))
{
//PART I - DO TWO POLIGONS INTERSECT?
//POSSIBLE RESULTS: INTERSECT, NOT_INTERSECT, COPLANAR
//distance from the face1 vertices to the face2 plane
distFace1Vert1 = ComputeDistance(face1.V1, face2);
distFace1Vert2 = ComputeDistance(face1.V2, face2);
distFace1Vert3 = ComputeDistance(face1.V3, face2);
//distances signs from the face1 vertices to the face2 plane
signFace1Vert1 = (distFace1Vert1 > EqualityTolerance ? 1 : (distFace1Vert1 < -EqualityTolerance ? -1 : 0));
signFace1Vert2 = (distFace1Vert2 > EqualityTolerance ? 1 : (distFace1Vert2 < -EqualityTolerance ? -1 : 0));
signFace1Vert3 = (distFace1Vert3 > EqualityTolerance ? 1 : (distFace1Vert3 < -EqualityTolerance ? -1 : 0));
//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 (!(signFace1Vert1 == signFace1Vert2 && signFace1Vert2 == signFace1Vert3))
{
//distance from the face2 vertices to the face1 plane
distFace2Vert1 = ComputeDistance(face2.V1, face1);
distFace2Vert2 = ComputeDistance(face2.V2, face1);
distFace2Vert3 = ComputeDistance(face2.V3, face1);
//distances signs from the face2 vertices to the face1 plane
signFace2Vert1 = (distFace2Vert1 > EqualityTolerance ? 1 : (distFace2Vert1 < -EqualityTolerance ? -1 : 0));
signFace2Vert2 = (distFace2Vert2 > EqualityTolerance ? 1 : (distFace2Vert2 < -EqualityTolerance ? -1 : 0));
signFace2Vert3 = (distFace2Vert3 > EqualityTolerance ? 1 : (distFace2Vert3 < -EqualityTolerance ? -1 : 0));
//if the signs are not equal...
if (!(signFace2Vert1 == signFace2Vert2 && signFace2Vert2 == signFace2Vert3))
{
line = new Line(face1, face2);
//intersection of the face1 and the plane of face2
segment1 = new Segment(line, face1, signFace1Vert1, signFace1Vert2, signFace1Vert3);
//intersection of the face2 and the plane of face1
segment2 = new Segment(line, face2, signFace2Vert1, signFace2Vert2, signFace2Vert3);
//if the two segments intersect...
if (segment1.Intersect(segment2))
{
//PART II - SUBDIVIDING NON-COPLANAR POLYGONS
int lastNumFaces = NumFaces;
SplitFace(i, segment1, segment2);
//prevent from infinite loop (with a loss of faces...)
//if(numFacesStart*20<getNumFaces())
//{
// System.out.println("possible infinite loop situation: terminating faces split");
// return;
//}
//if the face in the position isn't the same, there was a break
if (face1 != GetFace(i))
{
//if the generated solid is equal the origin...
if (face1.Equals(GetFace(NumFaces - 1)))
{
//return it to its position and jump it
if (i != (NumFaces - 1))
{
Faces.RemoveAt(NumFaces - 1);
Faces.Insert(i, face1);
}
else
{
continue;
}
}
//else: test next face
else
{
i--;
break;
}
}
}
}
}
}
}
}
}
}
}