fix #35; check edge validity;

include/bounce/quickhull/qh_hull.h

@@ -67,6 +67,14 @@ struct qhFace
 
 struct qhHalfEdge
 {
+	enum State
+	{
+		e_used,
+		e_deleted
+	};
+	
+	State state;
+
 	qhHalfEdge* freeNext;
 
 	qhVertex* tail;

include/bounce/quickhull/qh_hull.inl

@@ -121,11 +121,7 @@ inline void qhFace::ComputeCenterAndPlane()
 
 // Given a number of points return the required memory size in 
 // bytes for constructing the convex hull of those points. 
-// This function uses constant expression (C++11). Therefore, you can evaluate 
-// its value at compile-time. That is particularly usefull when you want to 
-// create a stack buffer from a constant number of vertices. 
-// Due to the constexpr specifier, this function is automatically inlined.
-constexpr u32 qhGetBufferSize(u32 pointCount)
+inline u32 qhGetBufferSize(u32 pointCount)
 {
 	u32 size = 0;
 
@@ -179,12 +175,14 @@ inline void qhHull::FreeVertex(qhVertex* v)
 inline qhHalfEdge* qhHull::AllocateEdge()
 {
 	qhHalfEdge* e = m_freeEdges;
+	e->state = qhHalfEdge::e_used;
 	m_freeEdges = e->freeNext;
 	return e;
 }
 
 inline void qhHull::FreeEdge(qhHalfEdge* e)
 {
+	e->state = qhHalfEdge::e_deleted;
 	e->freeNext = m_freeEdges;
 	m_freeEdges = e;
 }

src/bounce/collision/shapes/qhull.cpp

@@ -172,8 +172,8 @@ void b3QHull::Set(const b3Vec3* points, u32 count)
 	// Create a convex hull.
 	
 	// Allocate memory buffer for the worst case.
-	const u32 qhBufferSize = qhGetBufferSize(B3_MAX_HULL_VERTICES);
-	u8 qhBuffer[qhBufferSize];
+	u32 qhBufferSize = qhGetBufferSize(B3_MAX_HULL_VERTICES);
+	void* qhBuffer = b3Alloc(qhBufferSize);
 
 	// Build
 	qhHull hull;
@@ -191,6 +191,7 @@ void b3QHull::Set(const b3Vec3* points, u32 count)
 		if (fs_count == B3_MAX_HULL_FACES)
 		{
 			// Face excess
+			b3Free(qhBuffer);
 			return;
 		}
 		
@@ -206,6 +207,7 @@ void b3QHull::Set(const b3Vec3* points, u32 count)
 			if (iv == B3_MAX_HULL_VERTICES)
 			{
 				// Vertex excess
+				b3Free(qhBuffer);
 				return;
 			}
 
@@ -214,6 +216,7 @@ void b3QHull::Set(const b3Vec3* points, u32 count)
 			if (iedge == B3_MAX_HULL_EDGES)
 			{
 				// Half-edge excess
+				b3Free(qhBuffer);
 				return;
 			}
 
@@ -222,6 +225,7 @@ void b3QHull::Set(const b3Vec3* points, u32 count)
 			if (itwin == B3_MAX_HULL_EDGES)
 			{
 				// Half-edge excess
+				b3Free(qhBuffer);
 				return;
 			}
 
@@ -271,6 +275,8 @@ void b3QHull::Set(const b3Vec3* points, u32 count)
 		++iface;
 	}
 
+	b3Free(qhBuffer);
+
 	B3_ASSERT(vs.count <= B3_MAX_HULL_VERTICES);
 	vertexCount = vs.count;
 

src/bounce/quickhull/qh_hull.cpp

@@ -768,6 +768,8 @@ 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;