text: //
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  // Copyright (c) 2008-2018 NVIDIA Corporation. All rights reserved.
  // Copyright (c) 2004-2008 AGEIA Technologies, Inc. All rights reserved.
  // Copyright (c) 2001-2004 NovodeX AG. All rights reserved.  
  
  
  #ifndef PX_COLLISION_NXTRIANGLEMESHDESC
  #define PX_COLLISION_NXTRIANGLEMESHDESC
  /** \addtogroup cooking
  @{
  */
  
  #include "PxPhysXConfig.h"
  #include "geometry/PxSimpleTriangleMesh.h"
  
  #if !PX_DOXYGEN
  namespace physx
  {
  #endif
  
  /**
  \brief Descriptor class for #PxTriangleMesh.
  
  Note that this class is derived from PxSimpleTriangleMesh which contains the members that describe the basic mesh.
  The mesh data is *copied* when an PxTriangleMesh object is created from this descriptor. After the call the
  user may discard the triangle data.
  
  @see PxTriangleMesh PxTriangleMeshGeometry PxShape
  */
  class PxTriangleMeshDesc : public PxSimpleTriangleMesh
  {
  public:
  
  	/**
  	Optional pointer to first material index, or NULL. There are PxSimpleTriangleMesh::numTriangles indices in total.
  	Caller may add materialIndexStride bytes to the pointer to access the next triangle.
  
  	When a triangle mesh collides with another object, a material is required at the collision point.
  	If materialIndices is NULL, then the material of the PxShape instance is used.
  	Otherwise, if the point of contact is on a triangle with index i, then the material index is determined as: 
  	PxMaterialTableIndex	index = *(PxMaterialTableIndex *)(((PxU8*)materialIndices) + materialIndexStride * i);
  
  	If the contact point falls on a vertex or an edge, a triangle adjacent to the vertex or edge is selected, and its index
  	used to look up a material. The selection is arbitrary but consistent over time. 
  
  	<b>Default:</b> NULL
  
  	@see materialIndexStride
  	*/
  	PxTypedStridedData<PxMaterialTableIndex> materialIndices;
  
  	/**
  	\brief Constructor sets to default.
  	*/
  	PX_INLINE PxTriangleMeshDesc();	
  
  	/**
  	\brief (re)sets the structure to the default.	
  	*/
  	PX_INLINE void setToDefault();
  
  	/**
  	\brief Returns true if the descriptor is valid.
  	\return true if the current settings are valid
  	*/
  	PX_INLINE bool isValid() const;
  };
  
  PX_INLINE PxTriangleMeshDesc::PxTriangleMeshDesc()	//constructor sets to default
  {
  	PxSimpleTriangleMesh::setToDefault();	
  }
  
  PX_INLINE void PxTriangleMeshDesc::setToDefault()
  {
  	*this = PxTriangleMeshDesc();
  }
  
  PX_INLINE bool PxTriangleMeshDesc::isValid() const
  {
  	if(points.count < 3) 	//at least 1 trig's worth of points
  		return false;
  	if ((!triangles.data) && (points.count%3))		// Non-indexed mesh => we must ensure the geometry defines an implicit number of triangles // i.e. numVertices can't be divided by 3
  		return false;
  	//add more validity checks here
  	if (materialIndices.data && materialIndices.stride < sizeof(PxMaterialTableIndex))
  		return false;
  	return PxSimpleTriangleMesh::isValid();
  }
  
  #if !PX_DOXYGEN
  } // namespace physx
  #endif
  
  /** @} */
  #endif
  