mesh.h

/*
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Open Asset Import Library (assimp)
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*/

/** @file mesh.h
 *  @brief Declares the data structures in which the imported geometry is
    returned by ASSIMP: aiMesh, aiFace and aiBone data structures.
 */
#ifndef INCLUDED_AI_MESH_H
#define INCLUDED_AI_MESH_H

#include "types.h"

#ifdef __cplusplus
extern "C" {
#endif

// ---------------------------------------------------------------------------
// Limits. These values are required to match the settings Assimp was
// compiled against. Therfore, do not redefine them unless you build the
// library from source using the same definitions.
// ---------------------------------------------------------------------------

/** @def AI_MAX_FACE_INDICES
 *  Maximum number of indices per face (polygon). */

#ifndef AI_MAX_FACE_INDICES
#   define AI_MAX_FACE_INDICES 0x7fff
#endif

/** @def AI_MAX_BONE_WEIGHTS
 *  Maximum number of indices per face (polygon). */

#ifndef AI_MAX_BONE_WEIGHTS
#   define AI_MAX_BONE_WEIGHTS 0x7fffffff
#endif

/** @def AI_MAX_VERTICES
 *  Maximum number of vertices per mesh.  */

#ifndef AI_MAX_VERTICES
#   define AI_MAX_VERTICES 0x7fffffff
#endif

/** @def AI_MAX_FACES
 *  Maximum number of faces per mesh. */

#ifndef AI_MAX_FACES
#   define AI_MAX_FACES 0x7fffffff
#endif

/** @def AI_MAX_NUMBER_OF_COLOR_SETS
 *  Supported number of vertex color sets per mesh. */

#ifndef AI_MAX_NUMBER_OF_COLOR_SETS
#   define AI_MAX_NUMBER_OF_COLOR_SETS 0x8
#endif // !! AI_MAX_NUMBER_OF_COLOR_SETS

/** @def AI_MAX_NUMBER_OF_TEXTURECOORDS
 *  Supported number of texture coord sets (UV(W) channels) per mesh */

#ifndef AI_MAX_NUMBER_OF_TEXTURECOORDS
#   define AI_MAX_NUMBER_OF_TEXTURECOORDS 0x8
#endif // !! AI_MAX_NUMBER_OF_TEXTURECOORDS

// ---------------------------------------------------------------------------
/** @brief A single face in a mesh, referring to multiple vertices.
 *
 * If mNumIndices is 3, we call the face 'triangle', for mNumIndices > 3
 * it's called 'polygon' (hey, that's just a definition!).
 * <br>
 * aiMesh::mPrimitiveTypes can be queried to quickly examine which types of
 * primitive are actually present in a mesh. The #aiProcess_SortByPType flag
 * executes a special post-processing algorithm which splits meshes with
 * *different* primitive types mixed up (e.g. lines and triangles) in several
 * 'clean' submeshes. Furthermore there is a configuration option (
 * #AI_CONFIG_PP_SBP_REMOVE) to force #aiProcess_SortByPType to remove
 * specific kinds of primitives from the imported scene, completely and forever.
 * In many cases you'll probably want to set this setting to
 * @code
 * aiPrimitiveType_LINE|aiPrimitiveType_POINT
 * @endcode
 * Together with the #aiProcess_Triangulate flag you can then be sure that
 * #aiFace::mNumIndices is always 3.
 * @note Take a look at the @link data Data Structures page @endlink for
 * more information on the layout and winding order of a face.
 */
struct aiFace
{
    //! Number of indices defining this face.
    //! The maximum value for this member is #AI_MAX_FACE_INDICES.
    unsigned int mNumIndices;

    //! Pointer to the indices array. Size of the array is given in numIndices.
    unsigned int* mIndices;

#ifdef __cplusplus

    //! Default constructor
    aiFace()
      : mNumIndices( 0 )
      , mIndices( NULL )
    {
    }

    //! Default destructor. Delete the index array
    ~aiFace()
    {
        delete [] mIndices;
    }

    //! Copy constructor. Copy the index array
    aiFace( const aiFace& o)
      : mIndices( NULL )
    {
        *this = o;
    }

    //! Assignment operator. Copy the index array
    aiFace& operator = ( const aiFace& o)
    {
        if (&o == this)
            return *this;

        delete[] mIndices;
        mNumIndices = o.mNumIndices;
        if (mNumIndices) {
            mIndices = new unsigned int[mNumIndices];
            ::memcpy( mIndices, o.mIndices, mNumIndices * sizeof( unsigned int));
        }
        else {
            mIndices = NULL;
        }
        return *this;
    }

    //! Comparison operator. Checks whether the index array
    //! of two faces is identical
    bool operator== (const aiFace& o) const
    {
        if (mIndices == o.mIndices)return true;
        else if (mIndices && mNumIndices == o.mNumIndices)
        {
            for (unsigned int i = 0;i < this->mNumIndices;++i)
                if (mIndices[i] != o.mIndices[i])return false;
            return true;
        }
        return false;
    }

    //! Inverse comparison operator. Checks whether the index
    //! array of two faces is NOT identical
    bool operator != (const aiFace& o) const
    {
        return !(*this == o);
    }
#endif // __cplusplus
}; // struct aiFace


// ---------------------------------------------------------------------------
/** @brief A single influence of a bone on a vertex.
 */
struct aiVertexWeight
{
    //! Index of the vertex which is influenced by the bone.
    unsigned int mVertexId;

    //! The strength of the influence in the range (0...1).
    //! The influence from all bones at one vertex amounts to 1.
    float mWeight;

#ifdef __cplusplus

    //! Default constructor
    aiVertexWeight() { }

    //! Initialisation from a given index and vertex weight factor
    //! \param pID ID
    //! \param pWeight Vertex weight factor
    aiVertexWeight( unsigned int pID, float pWeight)
        : mVertexId( pID), mWeight( pWeight)
    { /* nothing to do here */ }

#endif // __cplusplus
};


// ---------------------------------------------------------------------------
/** @brief A single bone of a mesh.
 *
 *  A bone has a name by which it can be found in the frame hierarchy and by
 *  which it can be addressed by animations. In addition it has a number of
 *  influences on vertices.
 */
struct aiBone
{
    //! The name of the bone.
    C_STRUCT aiString mName;

    //! The number of vertices affected by this bone
    //! The maximum value for this member is #AI_MAX_BONE_WEIGHTS.
    unsigned int mNumWeights;

    //! The vertices affected by this bone
    C_STRUCT aiVertexWeight* mWeights;

    //! Matrix that transforms from mesh space to bone space in bind pose
    C_STRUCT aiMatrix4x4 mOffsetMatrix;

#ifdef __cplusplus

    //! Default constructor
    aiBone()
        : mName()
        , mNumWeights( 0 )
      , mWeights( NULL )
    {
    }

    //! Copy constructor
    aiBone(const aiBone& other)
      : mName( other.mName )
      , mNumWeights( other.mNumWeights )
      , mOffsetMatrix( other.mOffsetMatrix )
    {
        if (other.mWeights && other.mNumWeights)
        {
            mWeights = new aiVertexWeight[mNumWeights];
            ::memcpy(mWeights,other.mWeights,mNumWeights * sizeof(aiVertexWeight));
        }
    }

    //! Destructor - deletes the array of vertex weights
    ~aiBone()
    {
        delete [] mWeights;
    }
#endif // __cplusplus
};


// ---------------------------------------------------------------------------
/** @brief Enumerates the types of geometric primitives supported by Assimp.
 *
 *  @see aiFace Face data structure
 *  @see aiProcess_SortByPType Per-primitive sorting of meshes
 *  @see aiProcess_Triangulate Automatic triangulation
 *  @see AI_CONFIG_PP_SBP_REMOVE Removal of specific primitive types.
 */
enum aiPrimitiveType
{
    /** A point primitive.
     *
     * This is just a single vertex in the virtual world,
     * #aiFace contains just one index for such a primitive.
     */
    aiPrimitiveType_POINT       = 0x1,

    /** A line primitive.
     *
     * This is a line defined through a start and an end position.
     * #aiFace contains exactly two indices for such a primitive.
     */
    aiPrimitiveType_LINE        = 0x2,

    /** A triangular primitive.
     *
     * A triangle consists of three indices.
     */
    aiPrimitiveType_TRIANGLE    = 0x4,

    /** A higher-level polygon with more than 3 edges.
     *
     * A triangle is a polygon, but polygon in this context means
     * "all polygons that are not triangles". The "Triangulate"-Step
     * is provided for your convenience, it splits all polygons in
     * triangles (which are much easier to handle).
     */
    aiPrimitiveType_POLYGON     = 0x8,


    /** This value is not used. It is just here to force the
     *  compiler to map this enum to a 32 Bit integer.
     */
#ifndef SWIG
    _aiPrimitiveType_Force32Bit = INT_MAX
#endif
}; //! enum aiPrimitiveType

// Get the #aiPrimitiveType flag for a specific number of face indices
#define AI_PRIMITIVE_TYPE_FOR_N_INDICES(n) \
    ((n) > 3 ? aiPrimitiveType_POLYGON : (aiPrimitiveType)(1u << ((n)-1)))



// ---------------------------------------------------------------------------
/** @brief NOT CURRENTLY IN USE. An AnimMesh is an attachment to an #aiMesh stores per-vertex
 *  animations for a particular frame.
 *
 *  You may think of an #aiAnimMesh as a `patch` for the host mesh, which
 *  replaces only certain vertex data streams at a particular time.
 *  Each mesh stores n attached attached meshes (#aiMesh::mAnimMeshes).
 *  The actual relationship between the time line and anim meshes is
 *  established by #aiMeshAnim, which references singular mesh attachments
 *  by their ID and binds them to a time offset.
*/
struct aiAnimMesh
{
    /** Replacement for aiMesh::mVertices. If this array is non-NULL,
     *  it *must* contain mNumVertices entries. The corresponding
     *  array in the host mesh must be non-NULL as well - animation
     *  meshes may neither add or nor remove vertex components (if
     *  a replacement array is NULL and the corresponding source
     *  array is not, the source data is taken instead)*/
    C_STRUCT aiVector3D* mVertices;

    /** Replacement for aiMesh::mNormals.  */
    C_STRUCT aiVector3D* mNormals;

    /** Replacement for aiMesh::mTangents. */
    C_STRUCT aiVector3D* mTangents;

    /** Replacement for aiMesh::mBitangents. */
    C_STRUCT aiVector3D* mBitangents;

    /** Replacement for aiMesh::mColors */
    C_STRUCT aiColor4D* mColors[AI_MAX_NUMBER_OF_COLOR_SETS];

    /** Replacement for aiMesh::mTextureCoords */
    C_STRUCT aiVector3D* mTextureCoords[AI_MAX_NUMBER_OF_TEXTURECOORDS];

    /** The number of vertices in the aiAnimMesh, and thus the length of all
     * the member arrays.
     *
     * This has always the same value as the mNumVertices property in the
     * corresponding aiMesh. It is duplicated here merely to make the length
     * of the member arrays accessible even if the aiMesh is not known, e.g.
     * from language bindings.
     */
    unsigned int mNumVertices;

#ifdef __cplusplus

    aiAnimMesh()
        : mVertices( NULL )
        , mNormals( NULL )
        , mTangents( NULL )
        , mBitangents( NULL )
        , mNumVertices( 0 )
    {
        // fixme consider moving this to the ctor initializer list as well
        for( unsigned int a = 0; a < AI_MAX_NUMBER_OF_TEXTURECOORDS; a++){
            mTextureCoords[a] = NULL;
        }
        for( unsigned int a = 0; a < AI_MAX_NUMBER_OF_COLOR_SETS; a++) {
            mColors[a] = NULL;
        }
    }

    ~aiAnimMesh()
    {
        delete [] mVertices;
        delete [] mNormals;
        delete [] mTangents;
        delete [] mBitangents;
        for( unsigned int a = 0; a < AI_MAX_NUMBER_OF_TEXTURECOORDS; a++) {
            delete [] mTextureCoords[a];
        }
        for( unsigned int a = 0; a < AI_MAX_NUMBER_OF_COLOR_SETS; a++) {
            delete [] mColors[a];
        }
    }

    /** Check whether the anim mesh overrides the vertex positions
     *  of its host mesh*/
    bool HasPositions() const {
        return mVertices != NULL;
    }

    /** Check whether the anim mesh overrides the vertex normals
     *  of its host mesh*/
    bool HasNormals() const {
        return mNormals != NULL;
    }

    /** Check whether the anim mesh overrides the vertex tangents
     *  and bitangents of its host mesh. As for aiMesh,
     *  tangents and bitangents always go together. */
    bool HasTangentsAndBitangents() const {
        return mTangents != NULL;
    }

    /** Check whether the anim mesh overrides a particular
     * set of vertex colors on his host mesh.
     *  @param pIndex 0<index<AI_MAX_NUMBER_OF_COLOR_SETS */
    bool HasVertexColors( unsigned int pIndex) const    {
        return pIndex >= AI_MAX_NUMBER_OF_COLOR_SETS ? false : mColors[pIndex] != NULL;
    }

    /** Check whether the anim mesh overrides a particular
     * set of texture coordinates on his host mesh.
     *  @param pIndex 0<index<AI_MAX_NUMBER_OF_TEXTURECOORDS */
    bool HasTextureCoords( unsigned int pIndex) const   {
        return pIndex >= AI_MAX_NUMBER_OF_TEXTURECOORDS ? false : mTextureCoords[pIndex] != NULL;
    }

#endif
};


// ---------------------------------------------------------------------------
/** @brief A mesh represents a geometry or model with a single material.
*
* It usually consists of a number of vertices and a series of primitives/faces
* referencing the vertices. In addition there might be a series of bones, each
* of them addressing a number of vertices with a certain weight. Vertex data
* is presented in channels with each channel containing a single per-vertex
* information such as a set of texture coords or a normal vector.
* If a data pointer is non-null, the corresponding data stream is present.
* From C++-programs you can also use the comfort functions Has*() to
* test for the presence of various data streams.
*
* A Mesh uses only a single material which is referenced by a material ID.
* @note The mPositions member is usually not optional. However, vertex positions
* *could* be missing if the #AI_SCENE_FLAGS_INCOMPLETE flag is set in
* @code
* aiScene::mFlags
* @endcode
*/
struct aiMesh
{
    /** Bitwise combination of the members of the #aiPrimitiveType enum.
     * This specifies which types of primitives are present in the mesh.
     * The "SortByPrimitiveType"-Step can be used to make sure the
     * output meshes consist of one primitive type each.
     */
    unsigned int mPrimitiveTypes;

    /** The number of vertices in this mesh.
    * This is also the size of all of the per-vertex data arrays.
    * The maximum value for this member is #AI_MAX_VERTICES.
    */
    unsigned int mNumVertices;

    /** The number of primitives (triangles, polygons, lines) in this  mesh.
    * This is also the size of the mFaces array.
    * The maximum value for this member is #AI_MAX_FACES.
    */
    unsigned int mNumFaces;

    /** Vertex positions.
    * This array is always present in a mesh. The array is
    * mNumVertices in size.
    */
    C_STRUCT aiVector3D* mVertices;

    /** Vertex normals.
    * The array contains normalized vectors, NULL if not present.
    * The array is mNumVertices in size. Normals are undefined for
    * point and line primitives. A mesh consisting of points and
    * lines only may not have normal vectors. Meshes with mixed
    * primitive types (i.e. lines and triangles) may have normals,
    * but the normals for vertices that are only referenced by
    * point or line primitives are undefined and set to QNaN (WARN:
    * qNaN compares to inequal to *everything*, even to qNaN itself.
    * Using code like this to check whether a field is qnan is:
    * @code
    * #define IS_QNAN(f) (f != f)
    * @endcode
    * still dangerous because even 1.f == 1.f could evaluate to false! (
    * remember the subtleties of IEEE754 artithmetics). Use stuff like
    * @c fpclassify instead.
    * @note Normal vectors computed by Assimp are always unit-length.
    * However, this needn't apply for normals that have been taken
    *   directly from the model file.
    */
    C_STRUCT aiVector3D* mNormals;

    /** Vertex tangents.
    * The tangent of a vertex points in the direction of the positive
    * X texture axis. The array contains normalized vectors, NULL if
    * not present. The array is mNumVertices in size. A mesh consisting
    * of points and lines only may not have normal vectors. Meshes with
    * mixed primitive types (i.e. lines and triangles) may have
    * normals, but the normals for vertices that are only referenced by
    * point or line primitives are undefined and set to qNaN.  See
    * the #mNormals member for a detailed discussion of qNaNs.
    * @note If the mesh contains tangents, it automatically also
    * contains bitangents.
    */
    C_STRUCT aiVector3D* mTangents;

    /** Vertex bitangents.
    * The bitangent of a vertex points in the direction of the positive
    * Y texture axis. The array contains normalized vectors, NULL if not
    * present. The array is mNumVertices in size.
    * @note If the mesh contains tangents, it automatically also contains
    * bitangents.
    */
    C_STRUCT aiVector3D* mBitangents;

    /** Vertex color sets.
    * A mesh may contain 0 to #AI_MAX_NUMBER_OF_COLOR_SETS vertex
    * colors per vertex. NULL if not present. Each array is
    * mNumVertices in size if present.
    */
    C_STRUCT aiColor4D* mColors[AI_MAX_NUMBER_OF_COLOR_SETS];

    /** Vertex texture coords, also known as UV channels.
    * A mesh may contain 0 to AI_MAX_NUMBER_OF_TEXTURECOORDS per
    * vertex. NULL if not present. The array is mNumVertices in size.
    */
    C_STRUCT aiVector3D* mTextureCoords[AI_MAX_NUMBER_OF_TEXTURECOORDS];

    /** Specifies the number of components for a given UV channel.
    * Up to three channels are supported (UVW, for accessing volume
    * or cube maps). If the value is 2 for a given channel n, the
    * component p.z of mTextureCoords[n][p] is set to 0.0f.
    * If the value is 1 for a given channel, p.y is set to 0.0f, too.
    * @note 4D coords are not supported
    */
    unsigned int mNumUVComponents[AI_MAX_NUMBER_OF_TEXTURECOORDS];

    /** The faces the mesh is constructed from.
    * Each face refers to a number of vertices by their indices.
    * This array is always present in a mesh, its size is given
    * in mNumFaces. If the #AI_SCENE_FLAGS_NON_VERBOSE_FORMAT
    * is NOT set each face references an unique set of vertices.
    */
    C_STRUCT aiFace* mFaces;

    /** The number of bones this mesh contains.
    * Can be 0, in which case the mBones array is NULL.
    */
    unsigned int mNumBones;

    /** The bones of this mesh.
    * A bone consists of a name by which it can be found in the
    * frame hierarchy and a set of vertex weights.
    */
    C_STRUCT aiBone** mBones;

    /** The material used by this mesh.
     * A mesh uses only a single material. If an imported model uses
     * multiple materials, the import splits up the mesh. Use this value
     * as index into the scene's material list.
     */
    unsigned int mMaterialIndex;

    /** Name of the mesh. Meshes can be named, but this is not a
     *  requirement and leaving this field empty is totally fine.
     *  There are mainly three uses for mesh names:
     *   - some formats name nodes and meshes independently.
     *   - importers tend to split meshes up to meet the
     *      one-material-per-mesh requirement. Assigning
     *      the same (dummy) name to each of the result meshes
     *      aids the caller at recovering the original mesh
     *      partitioning.
     *   - Vertex animations refer to meshes by their names.
     **/
    C_STRUCT aiString mName;


    /** NOT CURRENTLY IN USE. The number of attachment meshes */
    unsigned int mNumAnimMeshes;

    /** NOT CURRENTLY IN USE. Attachment meshes for this mesh, for vertex-based animation.
     *  Attachment meshes carry replacement data for some of the
     *  mesh'es vertex components (usually positions, normals). */
    C_STRUCT aiAnimMesh** mAnimMeshes;


#ifdef __cplusplus

    //! Default constructor. Initializes all members to 0
    aiMesh()
        : mPrimitiveTypes( 0 )
        , mNumVertices( 0 )
        , mNumFaces( 0 )
        , mVertices( NULL )
        , mNormals( NULL )
        , mTangents( NULL )
        , mBitangents( NULL )
        , mFaces( NULL )
        , mNumBones( 0 )
        , mBones( NULL )
        , mMaterialIndex( 0 )
        , mNumAnimMeshes( 0 )
        , mAnimMeshes( NULL )
    {
        for( unsigned int a = 0; a < AI_MAX_NUMBER_OF_TEXTURECOORDS; a++)
        {
            mNumUVComponents[a] = 0;
            mTextureCoords[a] = NULL;
        }

        for( unsigned int a = 0; a < AI_MAX_NUMBER_OF_COLOR_SETS; a++)
            mColors[a] = NULL;
    }

    //! Deletes all storage allocated for the mesh
    ~aiMesh()
    {
        delete [] mVertices;
        delete [] mNormals;
        delete [] mTangents;
        delete [] mBitangents;
        for( unsigned int a = 0; a < AI_MAX_NUMBER_OF_TEXTURECOORDS; a++) {
            delete [] mTextureCoords[a];
        }
        for( unsigned int a = 0; a < AI_MAX_NUMBER_OF_COLOR_SETS; a++) {
            delete [] mColors[a];
        }

        // DO NOT REMOVE THIS ADDITIONAL CHECK
        if (mNumBones && mBones)    {
            for( unsigned int a = 0; a < mNumBones; a++) {
                delete mBones[a];
            }
            delete [] mBones;
        }

        if (mNumAnimMeshes && mAnimMeshes)  {
            for( unsigned int a = 0; a < mNumAnimMeshes; a++) {
                delete mAnimMeshes[a];
            }
            delete [] mAnimMeshes;
        }

        delete [] mFaces;
    }

    //! Check whether the mesh contains positions. Provided no special
    //! scene flags are set, this will always be true
    bool HasPositions() const
        { return mVertices != NULL && mNumVertices > 0; }

    //! Check whether the mesh contains faces. If no special scene flags
    //! are set this should always return true
    bool HasFaces() const
        { return mFaces != NULL && mNumFaces > 0; }

    //! Check whether the mesh contains normal vectors
    bool HasNormals() const
        { return mNormals != NULL && mNumVertices > 0; }

    //! Check whether the mesh contains tangent and bitangent vectors
    //! It is not possible that it contains tangents and no bitangents
    //! (or the other way round). The existence of one of them
    //! implies that the second is there, too.
    bool HasTangentsAndBitangents() const
        { return mTangents != NULL && mBitangents != NULL && mNumVertices > 0; }

    //! Check whether the mesh contains a vertex color set
    //! \param pIndex Index of the vertex color set
    bool HasVertexColors( unsigned int pIndex) const
    {
        if( pIndex >= AI_MAX_NUMBER_OF_COLOR_SETS)
            return false;
        else
            return mColors[pIndex] != NULL && mNumVertices > 0;
    }

    //! Check whether the mesh contains a texture coordinate set
    //! \param pIndex Index of the texture coordinates set
    bool HasTextureCoords( unsigned int pIndex) const
    {
        if( pIndex >= AI_MAX_NUMBER_OF_TEXTURECOORDS)
            return false;
        else
            return mTextureCoords[pIndex] != NULL && mNumVertices > 0;
    }

    //! Get the number of UV channels the mesh contains
    unsigned int GetNumUVChannels() const
    {
        unsigned int n = 0;
        while (n < AI_MAX_NUMBER_OF_TEXTURECOORDS && mTextureCoords[n])++n;
        return n;
    }

    //! Get the number of vertex color channels the mesh contains
    unsigned int GetNumColorChannels() const
    {
        unsigned int n = 0;
        while (n < AI_MAX_NUMBER_OF_COLOR_SETS && mColors[n])++n;
        return n;
    }

    //! Check whether the mesh contains bones
    inline bool HasBones() const
        { return mBones != NULL && mNumBones > 0; }

#endif // __cplusplus
};


#ifdef __cplusplus
}
#endif //! extern "C"
#endif // __AI_MESH_H_INC