/// <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; } } } } } } } } } } }