consistency

include/bounce/quickhull/qh_hull.h

@@ -34,18 +34,14 @@ struct qhList
 struct qhHalfEdge;
 struct qhVertex;
 
+enum qhFaceMark
+{
+	e_visible,
+	e_invisible
+};
+
 struct qhFace
 {
-	enum State
-	{
-		e_invisible,
-		e_visible,
-		e_unknown,
-		e_deleted
-	};
-
-	qhFace* freeNext;
-
 	qhFace* prev;
 	qhFace* next;
 
@@ -53,30 +49,25 @@ struct qhFace
 
 	qhList<qhVertex> conflictList;
 
-	State state;
 	b3Vec3 center;
 	b3Plane plane;
 
+	qhFaceMark mark;
+	
 	u32 GetVertexCount() const;
 	u32 GetEdgeCount() const;
 	
 	qhHalfEdge* FindHalfEdge(const qhVertex* v1, const qhVertex* v2) const;
 	
 	void ComputeCenterAndPlane();
+
+	//
+	qhFace* freeNext;
+	bool active;
 };
 
 struct qhHalfEdge
 {
-	enum State
-	{
-		e_used,
-		e_deleted
-	};
-	
-	State state;
-
-	qhHalfEdge* freeNext;
-
 	qhVertex* tail;
 
 	qhHalfEdge* prev;
@@ -84,18 +75,24 @@ struct qhHalfEdge
 	qhHalfEdge* twin;
 
 	qhFace* face;
+
+	//
+	qhHalfEdge* freeNext;
+	bool active;
 };
 
 struct qhVertex
 {
-	qhVertex* freeNext;
-
 	qhVertex* prev;
 	qhVertex* next;
 
 	b3Vec3 position;
 
 	qhFace* conflictFace;
+
+	//
+	qhVertex* freeNext;
+	bool active;
 };
 
 // A convex hull builder. 
@@ -128,6 +125,7 @@ public:
 private:
 	bool BuildInitialHull(const b3Vec3* vertices, u32 count);
 	qhFace* AddFace(qhVertex* v1, qhVertex* v2, qhVertex* v3);
+	qhFace* RemoveFace(qhFace* face);
 
 	qhVertex* FindEyeVertex() const;
 	void AddVertex(qhVertex* v);

include/bounce/quickhull/qh_hull.inl

@@ -162,12 +162,16 @@ inline const qhList<qhFace>& qhHull::GetFaceList() const
 inline qhVertex* qhHull::AllocateVertex()
 {
 	qhVertex* v = m_freeVertices;
+	B3_ASSERT(v->active == false);
+	v->active = true;
 	m_freeVertices = v->freeNext;
 	return v;
 }
 
 inline void qhHull::FreeVertex(qhVertex* v)
 {
+	//B3_ASSERT(v->active == true);
+	v->active = false;
 	v->freeNext = m_freeVertices;
 	m_freeVertices = v;
 }
@@ -175,14 +179,16 @@ inline void qhHull::FreeVertex(qhVertex* v)
 inline qhHalfEdge* qhHull::AllocateEdge()
 {
 	qhHalfEdge* e = m_freeEdges;
-	e->state = qhHalfEdge::e_used;
+	B3_ASSERT(e->active == false);
+	e->active = true;
 	m_freeEdges = e->freeNext;
 	return e;
 }
 
 inline void qhHull::FreeEdge(qhHalfEdge* e)
 {
-	e->state = qhHalfEdge::e_deleted;
+	//B3_ASSERT(e->active == true);
+	e->active = false;
 	e->freeNext = m_freeEdges;
 	m_freeEdges = e;
 }
@@ -190,13 +196,16 @@ inline void qhHull::FreeEdge(qhHalfEdge* e)
 inline qhFace* qhHull::AllocateFace()
 {
 	qhFace* f = m_freeFaces;
+	B3_ASSERT(f->active == false);
+	f->active = true;
 	m_freeFaces = f->freeNext;
 	return f;
 }
 
 inline void qhHull::FreeFace(qhFace* f)
 {
-	f->state = qhFace::e_deleted;
+	//B3_ASSERT(f->active == true);
+	f->active = false;
 	f->freeNext = m_freeFaces;
 	m_freeFaces = f;
 }

src/bounce/quickhull/qh_hull.cpp

@@ -352,17 +352,17 @@ void qhHull::AddVertex(qhVertex* eye)
 
 void qhHull::FindHorizon(qhVertex* eye)
 {
-	// Classify faces
+	// Mark faces
 	for (qhFace* face = m_faceList.head; face != NULL; face = face->next)
 	{
 		float32 d = b3Distance(eye->position, face->plane);
 		if (d > m_tolerance)
 		{
-			face->state = qhFace::e_visible;
+			face->mark = qhFaceMark::e_visible;
 		}
 		else
 		{
-			face->state = qhFace::e_invisible;
+			face->mark = qhFaceMark::e_invisible;
 		}
 	}
 
@@ -370,7 +370,7 @@ void qhHull::FindHorizon(qhVertex* eye)
 	m_horizonCount = 0;
 	for (qhFace* face = m_faceList.head; face != NULL; face = face->next)
 	{
-		if (face->state == qhFace::e_invisible)
+		if (face->mark == qhFaceMark::e_invisible)
 		{
 			continue;
 		}
@@ -382,7 +382,7 @@ void qhHull::FindHorizon(qhVertex* eye)
 			qhHalfEdge* twin = edge->twin;
 			qhFace* other = twin->face;
 
-			if (other->state == qhFace::e_invisible)
+			if (other->mark == qhFaceMark::e_invisible)
 			{
 				m_horizon[m_horizonCount++] = edge;
 			}
@@ -453,16 +453,14 @@ void qhHull::AddNewFaces(qhVertex* eye)
 	while (f)
 	{
 		// Invisible faces are maintained.
-		if (f->state == qhFace::e_invisible)
+		if (f->mark == qhFaceMark::e_invisible)
 		{
 			f = f->next;
 			continue;
 		}
 
-		// Remove the face
+		// Move the orphaned vertices into the new faces
-
+		// Also remove internal points 
-		// Assign orphaned vertices to the new faces
-		// Also discard internal points 
 		qhVertex* v = f->conflictList.head;
 		while (v)
 		{
@@ -499,27 +497,11 @@ void qhHull::AddNewFaces(qhVertex* eye)
 			}
 		}
 
-		// Remove face half-edges 
+		// Remove the face
-		qhHalfEdge* e = f->edge;
+		f = RemoveFace(f);
-		do
-		{
-			if (e->twin)
-			{
-				e->twin = NULL;
-			}
-
-			qhHalfEdge* e0 = e;
-			e = e->next;
-			FreeEdge(e0);
-		} while (e != f->edge);
-
-		// Remove face 
-		qhFace* f0 = f;
-		f = m_faceList.Remove(f);
-		FreeFace(f0);
 	}
 
-	// Connect the created faces with the remaining faces in the hull
+	// Add the new faces to the hull
 	for (u32 i = 0; i < m_newFaceCount; ++i)
 	{
 		qhFace* face = m_newFaces[i];
@@ -602,13 +584,40 @@ qhFace* qhHull::AddFace(qhVertex* v1, qhVertex* v2, qhVertex* v3)
 	face->edge = e1;
 	face->center = (v1->position + v2->position + v3->position) / 3.0f;
 	face->plane = b3Plane(v1->position, v2->position, v3->position);
-	face->state = qhFace::e_invisible;
 
 	m_faceList.PushFront(face);
 
 	return face;
 }
 
+qhFace* qhHull::RemoveFace(qhFace* face)
+{
+	// Remove half-edges 
+	qhHalfEdge* e = face->edge;
+	do
+	{
+		qhHalfEdge* twin = e->twin;
+
+		// Remove half-edge and its twin if twin face does not exist
+		if (twin->face == NULL || twin->face == e->face)
+		{
+			e->twin = NULL;
+
+			FreeEdge(twin);
+
+			qhHalfEdge* e0 = e;
+			e = e->next;
+			FreeEdge(e0);
+		}
+
+	} while (e != face->edge);
+
+	// Remove face 
+	qhFace* nextFace = m_faceList.Remove(face);
+	FreeFace(face);
+	return nextFace;
+}
+
 qhFace* qhHull::AddNewFace(qhVertex* v1, qhVertex* v2, qhVertex* v3)
 {
 	qhFace* face = AllocateFace();
@@ -640,7 +649,6 @@ qhFace* qhHull::AddNewFace(qhVertex* v1, qhVertex* v2, qhVertex* v3)
 	face->edge = e1;
 	face->center = (v1->position + v2->position + v3->position) / 3.0f;
 	face->plane = b3Plane(v1->position, v2->position, v3->position);
-	face->state = qhFace::e_invisible;
 
 	face->prev = NULL;
 	face->next = NULL;
@@ -730,8 +738,8 @@ void qhHull::MergeFaces()
 	{
 		qhFace* face = m_newFaces[i];
 
-		// Was the face merged?
+		// Was the face deleted due to merging?
-		if (face->state == qhFace::e_deleted)
+		if (face->active == false)
 		{
 			continue;
 		}
@@ -743,9 +751,13 @@ void qhHull::MergeFaces()
 
 void qhHull::Validate(const qhHalfEdge* edge) const
 {
+	B3_ASSERT(edge->active == true);
+
 	const qhHalfEdge* twin = edge->twin;
 	B3_ASSERT(twin->twin == edge);
 
+	//B3_ASSERT(edge->tail->active == true);
+
 	b3Vec3 A = edge->tail->position;
 	b3Vec3 B = twin->tail->position;
 	B3_ASSERT(b3DistanceSquared(A, B) > B3_EPSILON * B3_EPSILON);
@@ -766,8 +778,6 @@ void qhHull::Validate(const qhFace* face) const
 	const qhHalfEdge* edge = begin;
 	do
 	{
-		B3_ASSERT(edge->state != qhHalfEdge::e_deleted);
-
 		B3_ASSERT(edge->face == face);
 
 		qhHalfEdge* twin = edge->twin;
@@ -784,23 +794,24 @@ void qhHull::Validate() const
 {
 	for (qhFace* face = m_faceList.head; face != NULL; face = face->next)
 	{
-		B3_ASSERT(face->state != face->e_deleted);
+		B3_ASSERT(face->active == true);
+
+		for (qhVertex* vertex = face->conflictList.head; vertex != NULL; vertex = vertex->next)
+		{
+			B3_ASSERT(vertex->active == true);
+		}
+
 		Validate(face);
 	}
 }
 
 void qhHull::Draw() const
 {
-	b3StackArray<b3Vec3, 256> polygon;
+	for (qhFace* face = m_faceList.head; face != NULL; face = face->next)
-
-	qhFace* face = m_faceList.head;
-	while (face)
 	{
+		b3StackArray<b3Vec3, 256> polygon;
 		polygon.Resize(0);
 
-		b3Vec3 c = face->center;
-		b3Vec3 n = face->plane.normal;
-
 		const qhHalfEdge* begin = face->edge;
 		const qhHalfEdge* edge = begin;
 		do
@@ -809,6 +820,9 @@ void qhHull::Draw() const
 			edge = edge->next;
 		} while (edge != begin);
 
+		b3Vec3 c = face->center;
+		b3Vec3 n = face->plane.normal;
+
 		b3Draw_draw->DrawSolidPolygon(n, polygon.Begin(), polygon.Count(), b3Color(1.0f, 1.0f, 1.0f, 0.5f));
 
 		qhVertex* v = face->conflictList.head;
@@ -820,7 +834,5 @@ void qhHull::Draw() const
 		}
 
 		b3Draw_draw->DrawSegment(c, c + n, b3Color(1.0f, 1.0f, 1.0f));
-
-		face = face->next;
 	}
 }