[G+smo] gsMultiPatch 类

得到几何信息： 

/// Dimension of the parameter domain (must match for all patches).
    int parDim() const 

/// Dimension of the geometry (must match for all patches).
    int geoDim() const;

/// Number of patches
    std::size_t nPatches() const          { return m_patches.size(); }

得到patch和geometry：

/// Return the \a i-th patch.
    gsGeometry<T>& patch( std::size_t i ) const

/// Return the basis of the \a i-th patch.
    gsBasis<T> & basis( std::size_t i ) const;

/// Returns the range of parameter
    gsMatrix<T> parameterRange(int i = 0) const;

 /// Number of patches
    std::size_t nPatches() const          { return m_patches.size(); }

/// Returns a vector of patches // to do : replace by copies
    PatchContainer const& patches() const { return m_patches; }

/// Return the \a i-th patch.
    const gsGeometry<T> & operator []( size_t i ) const { return *m_patches[i]; }

 /// Makes a deep copy of all bases and puts them in a vector
    std::vector<gsBasis<T> *> basesCopy() const;

修改几何：
/// Add a patch.
    void addPatch( gsGeometry<T> * g );

/// Search for the given geometry and return its patch index.
    int findPatchIndex( gsGeometry<T>* g ) const;

/// Add boundary

void addPatchBoundary( gsGeometry<T>* g, boxSide s ) 

///几何的细化和升阶

void uniformRefine(int numKnots = 1, int mul = 1);
    void degreeElevate(int elevationSteps = 1);

/// Attempt to compute interfaces and boundaries automatically. 几何类的计算
    bool computeTopology( T tol = 1e-4 );

///初始化

/// Clear (delete) all patches
    void clear()

gsMultiPatch的声明：gsMultiPatch<> * patches;

gsMultiPatch的定义：patches = gsNurbsCreator<>::BSplineSquareGrid(1, 1, 2, -1,-1); 定义一个 1×1 NURBS片，每个片的边长为2，左下侧点坐标为（-1，-1）。

patches->patch(0).degreeElevate(1);    

for (int i = 0; i < numRefine; ++i)
        patches->patch(0).uniformRefine();

patches->degreeElevate(1); 
    for (int i = 0; i < numRefine; ++i)
        patches->uniformRefine();

gsMultiPatch<> * patches  = gsNurbsCreator<>::BSplineSquareGrid(2, 2, 1, -1,-1);

//Scaling
    //for ( size_t i = 0; i<patches->nPatches(); ++i)
    //    patches->patch(i).coefs().array() /= 10.0;
    //gsWrite(*patches,"scaledpatches");

附录

头文件：stable\src\gsCore\gs\gsMultiPatch.h