source: GTP/trunk/Lib/Vis/Preprocessing/src/Mesh.h @ 1005

#ifndef _Mesh_H__
#define _Mesh_H__

#include <vector>
using namespace std;
#include "Intersectable.h"
#include "Plane3.h"
#include "Matrix4x4.h"
#include "AxisAlignedBox3.h"
#include "Material.h"
#include "Containers.h"


namespace GtpVisibilityPreprocessor {

extern bool MeshDebug;

struct Triangle3;
class MeshInstance;
class MeshKdTree;

/// default vertex container for Mesh
typedef std::vector<Vector3> VertexContainer;

/// vertex index container
//typedef std::vector<short> VertexIndexContainer;
typedef std::vector<int> VertexIndexContainer;

/** Patch used as an element of the mesh */
struct Face {

public:
  Face(): mVertexIndices() {}

  Face(const int a, const int b, const int c):mVertexIndices(3) {
    mVertexIndices[0] = a;
    mVertexIndices[1] = b;
    mVertexIndices[2] = c;
  }

  Face(const int a, const int b, const int c, const int d): 
  mVertexIndices(4) {
    mVertexIndices[0] = a;
    mVertexIndices[1] = b;
    mVertexIndices[2] = c;
    mVertexIndices[3] = d;
  }

  Face(const VertexIndexContainer &vertices):mVertexIndices(vertices.size()) {
        for (int i=0;  i < vertices.size(); i++)
          mVertexIndices[i] = vertices[i];
  }
  
  /// list of vertex pointers
  VertexIndexContainer mVertexIndices;  
};



/// default vertex container for Mesh
typedef vector<Vector3> VertexContainer;

/// default patch container for Mesh
typedef std::vector<Face *> FaceContainer;

/** Mesh containing polygonal patches */
class Mesh {

public:

  /// Default constructor
  Mesh():mVertices(), mFaces(), mMaterial(NULL), mKdTree(NULL), mId(0) {}

  /// Constructor with container preallocation
  Mesh(const int vertices, const int faces):
    mFaces(),
    mMaterial(NULL),
    mKdTree(NULL),
    mVertices(),
    mIsConvex(false),
    mIsWatertight(false),
        mId(0)
  {
    mVertices.reserve(vertices);
    mFaces.reserve(faces);
  }

  /** Constructor setting a unqiue mesh id.
  */
  Mesh(const int id);

  /** Setting unique mesh id and using preallocation.
  */
  Mesh(const int id, const int vertices, const int faces);

  /** Copy constructor making a deep copy of the faces.
  */
  Mesh(const Mesh &rhs);

  /** Assignement operator.
        @note does not copy id
        @note preprocess may be necessary
  */
  Mesh& operator=(const Mesh& m);

  ~Mesh();
  void Clear();
  
  void IndexVertices();
  
  void AssignRandomMaterial();
  void AddTriangle(const Triangle3 &triangle);
  void AddRectangle(const Rectangle3 &triangle);

  void Cleanup();
  
  bool ValidateFace(const int face);

  void AddFace(Face *face) 
  {
    mFaces.push_back(face);
  }

  void ComputeBoundingBox();

  /** This function must be called after creating the mesh
        because it creates the local kd tree and the bounding box.
        */
  void Preprocess();

  /** Applies transformation to the mesh.
        @note: meshkdtree will most likely be outdated after transformation, thus 
        another preprocess might be necessary.  
        */
  void ApplyTransformation(const Matrix4x4 &m);

  /** Axis aligned bounding box of the mesh in local mesh coordinates.
  */
  AxisAlignedBox3 mBox;
  
  /** Vertices forming the mesh.
  */
  VertexContainer mVertices;
  
  /** Patches forming the mesh.
  */
  FaceContainer mFaces;
  
  /** Global mesh material.
  */
  Material *mMaterial;
  
  /** true if the mesh is a convex mesh.
  */
  bool mIsConvex;

  /** true if the mesh is a convex mesh.
  */
  bool mIsWatertight;

  MeshKdTree *mKdTree;

  int
  CastRay(Ray &ray, MeshInstance *instance);
        
  int
  CastRayToSelectedFaces(
                                                 Ray &ray,
                                                 const vector<int> &faces,
                                                 Intersectable *instance
                                                 );
        
  int
  CastRayToFace(
                                const int faceIndex,
                                Ray &ray,
                                float &nearestT,
                                int &nearestFace,
                                Intersectable *instance
                                );
        
  
  int
  RayFaceIntersection(const int faceIndex,
                                        const Ray &ray,
                                        float &t,
                                        const float nearestT
                                        );
  
  Plane3 GetFacePlane(const int faceIndex);

  AxisAlignedBox3 GetFaceBox(const int faceIndex);

  int GetRandomSurfacePoint(Vector3 &point, Vector3 &normal);

  int
  GetRandomVisibleSurfacePoint(Vector3 &point,
                                                           Vector3 &normal,
                                                           const Vector3 &viewpoint,
                                                           const int maxTries
                                                           );
 
  /** Returns unique mesh id.
  */
  int GetId() const
  {
          return mId;
  }

  virtual ostream &Describe(ostream &s) {
        return s<<"Mesh #vertices="<<(int)mVertices.size()<<" #faces="<<(int)mFaces.size();
  }
  
  /** Creates a mesh from a axis aligned bounding box.
      The mesh is handled from the resource manager.
  */
  friend Mesh *CreateMeshFromBox(const AxisAlignedBox3 &box);

 
protected:

  /// Unique id of this mesh.
  int mId;
};


class MeshInstance : public Intersectable {

public:
  MeshInstance(Mesh *mesh):Intersectable(), mMesh(mesh), mMaterial(NULL)
  {
  }

  int GetRandomSurfacePoint(Vector3 &point, Vector3 &normal);

        int
        GetRandomVisibleSurfacePoint(Vector3 &point,
                                                                                                                         Vector3 &normal,
                                                                                                                         const Vector3 &viewpoint,
                                                                                                                         const int maxTries
                                                                                                                         );


  Mesh *GetMesh() { return mMesh; }

  virtual AxisAlignedBox3 GetBox() {
    return mMesh->mBox;
  }

  virtual int CastRay(Ray &ray);

  virtual bool IsConvex() { return mMesh->mIsConvex; }
  virtual bool IsWatertight() { return mMesh->mIsWatertight; }
  virtual float IntersectionComplexity() {  return (float)mMesh->mFaces.size(); }

        virtual int NumberOfFaces() const {  return (int)mMesh->mFaces.size(); }

  virtual int Type() const { return MESH_INSTANCE; }

  virtual int
  CastRay(
          Ray &ray,
          const vector<int> &faces
          );


        virtual ostream &Describe(ostream &s) {
                s<<"MeshInstance Id="<<GetId();
                return mMesh->Describe(s);
        }
        
        /** Sets the material. this overrides the material from 
                the mesh itself.
        */
        void SetMaterial(Material *mat);

        /** Returns the material of this mesh instance.
                if not defined, returns the material of the mesh itself.
        */
        Material *GetMaterial() const;

protected:

        Mesh *mMesh;
        /** This material overrides the mesh material;
        */
        Material *mMaterial;  
};


/** This mesh instance includes a world transform. Use this
        class if the same mesh should be instantiated on different places.
*/
class TransformedMeshInstance: public MeshInstance
{
public:
  TransformedMeshInstance(Mesh *mesh);
  
  virtual AxisAlignedBox3 GetBox();
   
  
  virtual int CastRay(Ray &ray);

  virtual int CastRay(Ray &ray, const vector<int> &faces);

  virtual int Type() const { return TRANSFORMED_MESH_INSTANCE; }

  int GetRandomSurfacePoint(Vector3 &point, Vector3 &normal);

  /** Transforms this mesh instance by m.
  */
  void ApplyWorldTransform(const Matrix4x4 &m);

  /** Loads the transformation matrix into this mesh instance.
  */
  void LoadWorldTransform(const Matrix4x4 &m);

  /** The transformation is returned in m.
  */
  void GetWorldTransform(Matrix4x4 &m);

  /** Transforms a mesh according to the stored world transform.
        @param transformedMesh returns the tranformed mesh.
  */
  void GetTransformedMesh(Mesh &transformedMesh);

protected:

        /// the transformation matrix    
        Matrix4x4 mWorldTransform;
  
};

}

#endif