/*
Open Asset Import Library (assimp)
----------------------------------------------------------------------

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  following disclaimer.

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*/


/**
 * @file  MDLFileData.h
 * @brief Definition of in-memory structures for the MDL file format.
 *
 * The specification has been taken from various sources on the internet.
 * - http://tfc.duke.free.fr/coding/mdl-specs-en.html
 * - Conitec's MED SDK
 * - Many quite long HEX-editor sessions
 */

#ifndef AI_MDLFILEHELPER_H_INC
#define AI_MDLFILEHELPER_H_INC

#include <assimp/anim.h>
#include <assimp/mesh.h>
#include <assimp/Compiler/pushpack1.h>
#include <assimp/ByteSwapper.h>
#include <stdint.h>
#include <vector>

struct aiMaterial;

namespace Assimp {
namespace MDL {

// -------------------------------------------------------------------------------------
// to make it easier for us, we test the magic word against both "endiannesses"

// magic bytes used in Quake 1 MDL meshes
#define AI_MDL_MAGIC_NUMBER_BE  AI_MAKE_MAGIC("IDPO")
#define AI_MDL_MAGIC_NUMBER_LE  AI_MAKE_MAGIC("OPDI")

// magic bytes used in GameStudio A<very  low> MDL meshes
#define AI_MDL_MAGIC_NUMBER_BE_GS3  AI_MAKE_MAGIC("MDL2")
#define AI_MDL_MAGIC_NUMBER_LE_GS3  AI_MAKE_MAGIC("2LDM")

// magic bytes used in GameStudio A4 MDL meshes
#define AI_MDL_MAGIC_NUMBER_BE_GS4  AI_MAKE_MAGIC("MDL3")
#define AI_MDL_MAGIC_NUMBER_LE_GS4  AI_MAKE_MAGIC("3LDM")

// magic bytes used in GameStudio A5+ MDL meshes
#define AI_MDL_MAGIC_NUMBER_BE_GS5a AI_MAKE_MAGIC("MDL4")
#define AI_MDL_MAGIC_NUMBER_LE_GS5a AI_MAKE_MAGIC("4LDM")
#define AI_MDL_MAGIC_NUMBER_BE_GS5b AI_MAKE_MAGIC("MDL5")
#define AI_MDL_MAGIC_NUMBER_LE_GS5b AI_MAKE_MAGIC("5LDM")

// magic bytes used in GameStudio A7+ MDL meshes
#define AI_MDL_MAGIC_NUMBER_BE_GS7  AI_MAKE_MAGIC("MDL7")
#define AI_MDL_MAGIC_NUMBER_LE_GS7  AI_MAKE_MAGIC("7LDM")

// common limitations for Quake1 meshes. The loader does not check them,
// (however it warns) but models should not exceed these limits.
#if (!defined AI_MDL_VERSION)
#   define AI_MDL_VERSION               6
#endif
#if (!defined AI_MDL_MAX_FRAMES)
#   define AI_MDL_MAX_FRAMES            256
#endif
#if (!defined AI_MDL_MAX_UVS)
#   define AI_MDL_MAX_UVS               1024
#endif
#if (!defined AI_MDL_MAX_VERTS)
#   define AI_MDL_MAX_VERTS             1024
#endif
#if (!defined AI_MDL_MAX_TRIANGLES)
#   define AI_MDL_MAX_TRIANGLES         2048
#endif

// material key that is set for dummy materials that are
// just referencing another material
#if (!defined AI_MDL7_REFERRER_MATERIAL)
#   define AI_MDL7_REFERRER_MATERIAL "&&&referrer&&&",0,0
#endif

// -------------------------------------------------------------------------------------
/** \struct Header
 *  \brief Data structure for the MDL main header
 */
struct Header {
    //! magic number: "IDPO"
    uint32_t ident;

    //! version number: 6
    int32_t version;

    //! scale factors for each axis
    ai_real scale[3];

    //! translation factors for each axis
    ai_real translate[3];

    //! bounding radius of the mesh
    float boundingradius;

    //! Position of the viewer's exe. Ignored
    ai_real vEyePos[3];

    //! Number of textures
    int32_t num_skins;

    //! Texture width in pixels
    int32_t skinwidth;

    //! Texture height in pixels
    int32_t skinheight;

    //! Number of vertices contained in the file
    int32_t num_verts;

    //! Number of triangles contained in the file
    int32_t num_tris;

    //! Number of frames contained in the file
    int32_t num_frames;

    //! 0 = synchron, 1 = random . Ignored
    //! (MDLn formats: number of texture coordinates)
    int32_t synctype;

    //! State flag
    int32_t flags;

    //! Could be the total size of the file (and not a float)
    float size;
} PACK_STRUCT;


// -------------------------------------------------------------------------------------
/** \struct Header_MDL7
 *  \brief Data structure for the MDL 7 main header
 */
struct Header_MDL7 {
    //! magic number: "MDL7"
    char    ident[4];

    //! Version number. Ignored
    int32_t version;

    //! Number of bones in file
    uint32_t    bones_num;

    //! Number of groups in file
    uint32_t    groups_num;

    //! Size of data in the file
    uint32_t    data_size;

    //! Ignored. Used to store entity specific information
    int32_t entlump_size;

    //! Ignored. Used to store MED related data
    int32_t medlump_size;

    //! Size of the Bone_MDL7 data structure used in the file
    uint16_t bone_stc_size;

    //! Size of the Skin_MDL 7 data structure used in the file
    uint16_t skin_stc_size;

    //! Size of a single color (e.g. in a material)
    uint16_t colorvalue_stc_size;

    //! Size of the Material_MDL7 data structure used in the file
    uint16_t material_stc_size;

    //! Size of a texture coordinate set in the file
    uint16_t skinpoint_stc_size;

    //! Size of a triangle in the file
    uint16_t triangle_stc_size;

    //! Size of a normal vertex in the file
    uint16_t mainvertex_stc_size;

    //! Size of a per-frame animated vertex in the file
    //! (this is not supported)
    uint16_t framevertex_stc_size;

    //! Size of a bone animation matrix
    uint16_t bonetrans_stc_size;

    //! Size of the Frame_MDL7 data structure used in the file
    uint16_t frame_stc_size;
} PACK_STRUCT;


// -------------------------------------------------------------------------------------
/** \struct Bone_MDL7
 *  \brief Data structure for a bone in a MDL7 file
 */
struct Bone_MDL7 {
    //! Index of the parent bone of *this* bone. 0xffff means:
    //! "hey, I have no parent, I'm an orphan"
    uint16_t parent_index;
    uint8_t _unused_[2];

    //! Relative position of the bone (relative to the
    //! parent bone)
    float x,y,z;

    //! Optional name of the bone
    char name[1 /* DUMMY SIZE */];
} PACK_STRUCT;

#if (!defined AI_MDL7_BONE_STRUCT_SIZE__NAME_IS_20_CHARS)
#   define AI_MDL7_BONE_STRUCT_SIZE__NAME_IS_20_CHARS (16 + 20)
#endif

#if (!defined AI_MDL7_BONE_STRUCT_SIZE__NAME_IS_32_CHARS)
#   define AI_MDL7_BONE_STRUCT_SIZE__NAME_IS_32_CHARS (16 + 32)
#endif

#if (!defined AI_MDL7_BONE_STRUCT_SIZE__NAME_IS_NOT_THERE)
#   define AI_MDL7_BONE_STRUCT_SIZE__NAME_IS_NOT_THERE (16)
#endif

#if (!defined AI_MDL7_MAX_GROUPNAMESIZE)
#   define AI_MDL7_MAX_GROUPNAMESIZE    16
#endif // ! AI_MDL7_MAX_GROUPNAMESIZE

// -------------------------------------------------------------------------------------
/** \struct Group_MDL7
 *  \brief Group in a MDL7 file
 */
struct Group_MDL7 {
    //! = '1' -> triangle based Mesh
    unsigned char   typ;

    int8_t  deformers;
    int8_t  max_weights;
    int8_t  _unused_;

    //! size of data for this group in bytes ( MD7_GROUP stc. included).
    int32_t groupdata_size;
    char    name[AI_MDL7_MAX_GROUPNAMESIZE];

    //! Number of skins
    int32_t numskins;

    //! Number of texture coordinates
    int32_t num_stpts;

    //! Number of triangles
    int32_t numtris;

    //! Number of vertices
    int32_t numverts;

    //! Number of frames
    int32_t numframes;
} PACK_STRUCT;

#define AI_MDL7_SKINTYPE_MIPFLAG                0x08
#define AI_MDL7_SKINTYPE_MATERIAL               0x10
#define AI_MDL7_SKINTYPE_MATERIAL_ASCDEF        0x20
#define AI_MDL7_SKINTYPE_RGBFLAG                0x80

#if (!defined AI_MDL7_MAX_BONENAMESIZE)
#   define AI_MDL7_MAX_BONENAMESIZE 20
#endif // !! AI_MDL7_MAX_BONENAMESIZE

// -------------------------------------------------------------------------------------
/** \struct Deformer_MDL7
 *  \brief Deformer in a MDL7 file
 */
struct Deformer_MDL7 {
    int8_t  deformer_version;       // 0
    int8_t  deformer_typ;           // 0 - bones
    int8_t  _unused_[2];
    int32_t group_index;
    int32_t elements;
    int32_t deformerdata_size;
} PACK_STRUCT;


// -------------------------------------------------------------------------------------
/** \struct DeformerElement_MDL7
 *  \brief Deformer element in a MDL7 file
 */
struct DeformerElement_MDL7 {
    //! bei deformer_typ==0 (==bones) element_index == bone index
    int32_t element_index;
    char    element_name[AI_MDL7_MAX_BONENAMESIZE];
    int32_t weights;
} PACK_STRUCT;

// -------------------------------------------------------------------------------------
/** \struct DeformerWeight_MDL7
 *  \brief Deformer weight in a MDL7 file
 */
struct DeformerWeight_MDL7 {
    //! for deformer_typ==0 (==bones) index == vertex index
    int32_t index;
    float   weight;
} PACK_STRUCT;

// don't know why this was in the original headers ...
typedef int32_t MD7_MATERIAL_ASCDEFSIZE;

// -------------------------------------------------------------------------------------
/** \struct ColorValue_MDL7
 *  \brief Data structure for a color value in a MDL7 file
 */
struct ColorValue_MDL7 {
    float r,g,b,a;
} PACK_STRUCT;

// -------------------------------------------------------------------------------------
/** \struct Material_MDL7
 *  \brief Data structure for a Material in a MDL7 file
 */
struct Material_MDL7 {
    //! Diffuse base color of the material
    ColorValue_MDL7 Diffuse;

    //! Ambient base color of the material
    ColorValue_MDL7 Ambient;

    //! Specular base color of the material
    ColorValue_MDL7 Specular;

    //! Emissive base color of the material
    ColorValue_MDL7 Emissive;

    //! Phong power
    float           Power;
} PACK_STRUCT;

// -------------------------------------------------------------------------------------
/** \struct Skin
 *  \brief Skin data structure #1 - used by Quake1, MDL2, MDL3 and MDL4
 */
struct Skin {
    //! 0 = single (Skin), 1 = group (GroupSkin)
    //! For MDL3-5: Defines the type of the skin and there
    //! fore the size of the data to skip:
    //-------------------------------------------------------
    //! 2 for 565 RGB,
    //! 3 for 4444 ARGB,
    //! 10 for 565 mipmapped,
    //! 11 for 4444 mipmapped (bpp = 2),
    //! 12 for 888 RGB mipmapped (bpp = 3),
    //! 13 for 8888 ARGB mipmapped (bpp = 4)
    //-------------------------------------------------------
    int32_t group;

    //! Texture data
    uint8_t *data;
} PACK_STRUCT;


// -------------------------------------------------------------------------------------
/** \struct Skin
 *  \brief Skin data structure #2 - used by MDL5, MDL6 and MDL7
 *  \see Skin
 */
struct Skin_MDL5 {
    int32_t size, width, height;
    uint8_t *data;
} PACK_STRUCT;

// maximum length of texture file name
#if (!defined AI_MDL7_MAX_TEXNAMESIZE)
#   define AI_MDL7_MAX_TEXNAMESIZE      0x10
#endif

// ---------------------------------------------------------------------------
/** \struct Skin_MDL7
 *  \brief Skin data structure #3 - used by MDL7 and HMP7
 */
struct Skin_MDL7 {
    uint8_t         typ;
    int8_t          _unused_[3];
    int32_t         width;
    int32_t         height;
    char            texture_name[AI_MDL7_MAX_TEXNAMESIZE];
} PACK_STRUCT;

// -------------------------------------------------------------------------------------
/** \struct RGB565
 *  \brief Data structure for a RGB565 pixel in a texture
 */
struct RGB565 {
    uint16_t r : 5;
    uint16_t g : 6;
    uint16_t b : 5;
} PACK_STRUCT;

// -------------------------------------------------------------------------------------
/** \struct ARGB4
 *  \brief Data structure for a ARGB4444 pixel in a texture
 */
struct ARGB4 {
    uint16_t a : 4;
    uint16_t r : 4;
    uint16_t g : 4;
    uint16_t b : 4;
} /*PACK_STRUCT*/;

// -------------------------------------------------------------------------------------
/** \struct GroupSkin
 *  \brief Skin data structure #2 (group of pictures)
 */
struct GroupSkin {
    //! 0 = single (Skin), 1 = group (GroupSkin)
    int32_t group;

    //! Number of images
    int32_t nb;

    //! Time for each image
    float *time;

    //! Data of each image
    uint8_t **data;
} PACK_STRUCT;

// -------------------------------------------------------------------------------------
/** \struct TexCoord
 *  \brief Texture coordinate data structure used by the Quake1 MDL format
 */
struct TexCoord {
    //! Is the vertex on the noundary between front and back piece?
    int32_t onseam;

    //! Texture coordinate in the tx direction
    int32_t s;

    //! Texture coordinate in the ty direction
    int32_t t;
} PACK_STRUCT;

// -------------------------------------------------------------------------------------
/** \struct TexCoord_MDL3
 *  \brief Data structure for an UV coordinate in the 3DGS MDL3 format
 */
struct TexCoord_MDL3 {
    //! position, horizontally in range 0..skinwidth-1
    int16_t u;

    //! position, vertically in range 0..skinheight-1
    int16_t v;
} PACK_STRUCT;

// -------------------------------------------------------------------------------------
/** \struct TexCoord_MDL7
 *  \brief Data structure for an UV coordinate in the 3DGS MDL7 format
 */
struct TexCoord_MDL7 {
    //! position, horizontally in range 0..1
    float u;

    //! position, vertically in range 0..1
    float v;
} PACK_STRUCT;

// -------------------------------------------------------------------------------------
/** \struct SkinSet_MDL7
 *  \brief Skin set data structure for the 3DGS MDL7 format
 * MDL7 references UV coordinates per face via an index list.
 * This allows the use of multiple skins per face with just one
 * UV coordinate set.
 */
struct SkinSet_MDL7
{
    //! Index into the UV coordinate list
    uint16_t    st_index[3]; // size 6

    //! Material index
    int32_t     material;    // size 4
} PACK_STRUCT;

// -------------------------------------------------------------------------------------
/** \struct Triangle
 *  \brief Triangle data structure for the Quake1 MDL format
 */
struct Triangle
{
    //! 0 = backface, 1 = frontface
    int32_t facesfront;

    //! Vertex indices
    int32_t vertex[3];
} PACK_STRUCT;

// -------------------------------------------------------------------------------------
/** \struct Triangle_MDL3
 *  \brief Triangle data structure for the 3DGS MDL3 format
 */
struct Triangle_MDL3
{
    //!  Index of 3 3D vertices in range 0..numverts
    uint16_t index_xyz[3];

    //! Index of 3 skin vertices in range 0..numskinverts
    uint16_t index_uv[3];
} PACK_STRUCT;

// -------------------------------------------------------------------------------------
/** \struct Triangle_MDL7
 *  \brief Triangle data structure for the 3DGS MDL7 format
 */
struct Triangle_MDL7
{
    //! Vertex indices
    uint16_t   v_index[3];  // size 6

    //! Two skinsets. The second will be used for multi-texturing
    SkinSet_MDL7  skinsets[2];
} PACK_STRUCT;

#if (!defined AI_MDL7_TRIANGLE_STD_SIZE_ONE_UV)
#   define AI_MDL7_TRIANGLE_STD_SIZE_ONE_UV (6+sizeof(SkinSet_MDL7)-sizeof(uint32_t))
#endif
#if (!defined AI_MDL7_TRIANGLE_STD_SIZE_ONE_UV_WITH_MATINDEX)
#   define AI_MDL7_TRIANGLE_STD_SIZE_ONE_UV_WITH_MATINDEX (6+sizeof(SkinSet_MDL7))
#endif
#if (!defined AI_MDL7_TRIANGLE_STD_SIZE_TWO_UV)
#   define AI_MDL7_TRIANGLE_STD_SIZE_TWO_UV (6+2*sizeof(SkinSet_MDL7))
#endif

// Helper constants for Triangle::facesfront
#if (!defined AI_MDL_BACKFACE)
#   define AI_MDL_BACKFACE          0x0
#endif
#if (!defined  AI_MDL_FRONTFACE)
#   define AI_MDL_FRONTFACE         0x1
#endif

// -------------------------------------------------------------------------------------
/** \struct Vertex
 *  \brief Vertex data structure
 */
struct Vertex
{
    uint8_t v[3];
    uint8_t normalIndex;
} PACK_STRUCT;


// -------------------------------------------------------------------------------------
struct Vertex_MDL4
{
    uint16_t v[3];
    uint8_t normalIndex;
    uint8_t unused;
} PACK_STRUCT;

#define AI_MDL7_FRAMEVERTEX120503_STCSIZE       16
#define AI_MDL7_FRAMEVERTEX030305_STCSIZE       26

// -------------------------------------------------------------------------------------
/** \struct Vertex_MDL7
 *  \brief Vertex data structure used in MDL7 files
 */
struct Vertex_MDL7
{
    float   x,y,z;
    uint16_t vertindex; // = bone index
    union {
        uint8_t norm162index;
        float norm[3];
    } PACK_STRUCT;
} PACK_STRUCT;

// -------------------------------------------------------------------------------------
/** \struct BoneTransform_MDL7
 *  \brief bone transformation matrix structure used in MDL7 files
 */
struct BoneTransform_MDL7
{
    //! 4*3
    float   m [4*4];

    //! the index of this vertex, 0.. header::bones_num - 1
    uint16_t bone_index;

    //! I HATE 3DGS AND THE SILLY DEVELOPER WHO DESIGNED
    //! THIS STUPID FILE FORMAT!
    int8_t _unused_[2];
} PACK_STRUCT;


#define AI_MDL7_MAX_FRAMENAMESIZE       16

// -------------------------------------------------------------------------------------
/** \struct Frame_MDL7
 *  \brief Frame data structure used by MDL7 files
 */
struct Frame_MDL7
{
    char    frame_name[AI_MDL7_MAX_FRAMENAMESIZE];
    uint32_t    vertices_count;
    uint32_t    transmatrix_count;
};


// -------------------------------------------------------------------------------------
/** \struct SimpleFrame
 *  \brief Data structure for a simple frame
 */
struct SimpleFrame
{
    //! Minimum vertex of the bounding box
    Vertex bboxmin;

    //! Maximum vertex of the bounding box
    Vertex bboxmax;

    //! Name of the frame
    char name[16];

    //! Vertex list of the frame
    Vertex *verts;
} PACK_STRUCT;

// -------------------------------------------------------------------------------------
/** \struct Frame
 *  \brief Model frame data structure
 */
struct Frame
{
    //! 0 = simple frame, !0 = group frame
    int32_t type;

    //! Frame data
    SimpleFrame frame;
} PACK_STRUCT;


// -------------------------------------------------------------------------------------
struct SimpleFrame_MDLn_SP
{
    //! Minimum vertex of the bounding box
    Vertex_MDL4 bboxmin;

    //! Maximum vertex of the bounding box
    Vertex_MDL4 bboxmax;

    //! Name of the frame
    char name[16];

    //! Vertex list of the frame
    Vertex_MDL4 *verts;
} PACK_STRUCT;

// -------------------------------------------------------------------------------------
/** \struct GroupFrame
 *  \brief Data structure for a group of frames
 */
struct GroupFrame
{
    //! 0 = simple frame, !0 = group frame
    int32_t type;

    int32_t numframes;

    //! Minimum vertex for all single frames
    Vertex min;

    //! Maximum vertex for all single frames
    Vertex max;

    //! List of times for all single frames
    float *times;

    //! List of single frames
    SimpleFrame *frames;
} PACK_STRUCT;

#include <assimp/Compiler/poppack1.h>

// -------------------------------------------------------------------------------------
/** \struct IntFace_MDL7
 *  \brief Internal data structure to temporarily represent a face
 */
struct IntFace_MDL7 {
    // provide a constructor for our own convenience
    IntFace_MDL7() AI_NO_EXCEPT {
        ::memset( mIndices, 0, sizeof(uint32_t) *3);
        ::memset( iMatIndex, 0, sizeof( unsigned int) *2);
    }

    //! Vertex indices
    uint32_t mIndices[3];

    //! Material index (maximally two channels, which are joined later)
    unsigned int iMatIndex[2];
};

// -------------------------------------------------------------------------------------
/** \struct IntMaterial_MDL7
 *  \brief Internal data structure to temporarily represent a material
 *  which has been created from two single materials along with the
 *  original material indices.
 */
struct IntMaterial_MDL7 {
    // provide a constructor for our own convenience
    IntMaterial_MDL7() AI_NO_EXCEPT
    : pcMat( nullptr ) {
        ::memset( iOldMatIndices, 0, sizeof(unsigned int) *2);
    }

    //! Material instance
    aiMaterial* pcMat;

    //! Old material indices
    unsigned int iOldMatIndices[2];
};

// -------------------------------------------------------------------------------------
/** \struct IntBone_MDL7
 *  \brief Internal data structure to represent a bone in a MDL7 file with
 *  all of its animation channels assigned to it.
 */
struct IntBone_MDL7 : aiBone
{
    //! Default constructor
    IntBone_MDL7() AI_NO_EXCEPT : iParent (0xffff)
    {
        pkeyPositions.reserve(30);
        pkeyScalings.reserve(30);
        pkeyRotations.reserve(30);
    }

    //! Parent bone of the bone
    uint64_t iParent;

    //! Relative position of the bone
    aiVector3D vPosition;

    //! Array of position keys
    std::vector<aiVectorKey> pkeyPositions;

    //! Array of scaling keys
    std::vector<aiVectorKey> pkeyScalings;

    //! Array of rotation keys
    std::vector<aiQuatKey> pkeyRotations;
};

// -------------------------------------------------------------------------------------
//! Describes a MDL7 frame
struct IntFrameInfo_MDL7
{
    //! Construction from an existing frame header
    IntFrameInfo_MDL7(BE_NCONST MDL::Frame_MDL7* _pcFrame,unsigned int _iIndex)
        : iIndex(_iIndex)
        , pcFrame(_pcFrame)
    {}

    //! Index of the frame
    unsigned int iIndex;

    //! Points to the header of the frame
    BE_NCONST MDL::Frame_MDL7*  pcFrame;
};

// -------------------------------------------------------------------------------------
//! Describes a MDL7 mesh group
struct IntGroupInfo_MDL7
{
    //! Default constructor
    IntGroupInfo_MDL7() AI_NO_EXCEPT
        :   iIndex(0)
        ,   pcGroup(nullptr)
        ,   pcGroupUVs(nullptr)
        ,   pcGroupTris(nullptr)
        ,   pcGroupVerts(nullptr)
        {}

    //! Construction from an existing group header
    IntGroupInfo_MDL7(BE_NCONST MDL::Group_MDL7* _pcGroup, unsigned int _iIndex)
        :   iIndex(_iIndex)
        ,   pcGroup(_pcGroup)
        ,   pcGroupUVs()
        ,   pcGroupTris()
        ,   pcGroupVerts()
    {}

    //! Index of the group
    unsigned int iIndex;

    //! Points to the header of the group
    BE_NCONST MDL::Group_MDL7*      pcGroup;

    //! Points to the beginning of the uv coordinate section
    BE_NCONST MDL::TexCoord_MDL7*   pcGroupUVs;

    //! Points to the beginning of the triangle section
    MDL::Triangle_MDL7* pcGroupTris;

    //! Points to the beginning of the vertex section
    BE_NCONST MDL::Vertex_MDL7*     pcGroupVerts;
};

// -------------------------------------------------------------------------------------
//! Holds the data that belongs to a MDL7 mesh group
struct IntGroupData_MDL7
{
    IntGroupData_MDL7() AI_NO_EXCEPT
        : bNeed2UV(false)
    {}

    //! Array of faces that belong to the group
    std::vector<MDL::IntFace_MDL7> pcFaces;

    //! Array of vertex positions
    std::vector<aiVector3D>     vPositions;

    //! Array of vertex normals
    std::vector<aiVector3D>     vNormals;

    //! Array of bones indices
    std::vector<unsigned int>   aiBones;

    //! First UV coordinate set
    std::vector<aiVector3D>     vTextureCoords1;

    //! Optional second UV coordinate set
    std::vector<aiVector3D>     vTextureCoords2;

    //! Specifies whether there are two texture
    //! coordinate sets required
    bool bNeed2UV;
};

// -------------------------------------------------------------------------------------
//! Holds data from an MDL7 file that is shared by all mesh groups
struct IntSharedData_MDL7 {
    //! Default constructor
    IntSharedData_MDL7() AI_NO_EXCEPT
        : apcOutBones(),
        iNum()
    {
        abNeedMaterials.reserve(12);
    }

    //! Destruction: properly delete all allocated resources
    ~IntSharedData_MDL7()
    {
        // kill all bones
        if (this->apcOutBones)
        {
            for (unsigned int m = 0; m < iNum;++m)
                delete this->apcOutBones[m];
            delete[] this->apcOutBones;
        }
    }

    //! Specifies which materials are used
    std::vector<bool> abNeedMaterials;

    //! List of all materials
    std::vector<aiMaterial*> pcMats;

    //! List of all bones
    IntBone_MDL7** apcOutBones;

    //! number of bones
    unsigned int iNum;
};

// -------------------------------------------------------------------------------------
//! Contains input data for GenerateOutputMeshes_3DGS_MDL7
struct IntSplitGroupData_MDL7
{
    //! Construction from a given shared data set
    IntSplitGroupData_MDL7(IntSharedData_MDL7& _shared,
        std::vector<aiMesh*>& _avOutList)

        : aiSplit(), shared(_shared), avOutList(_avOutList)
    {
    }

    //! Destruction: properly delete all allocated resources
    ~IntSplitGroupData_MDL7()
    {
        // kill all face lists
        if(this->aiSplit)
        {
            for (unsigned int m = 0; m < shared.pcMats.size();++m)
                delete this->aiSplit[m];
            delete[] this->aiSplit;
        }
    }

    //! Contains a list of all faces per material
    std::vector<unsigned int>** aiSplit;

    //! Shared data for all groups of the model
    IntSharedData_MDL7& shared;

    //! List of meshes
    std::vector<aiMesh*>& avOutList;
};


}
} // end namespaces

#endif // !! AI_MDLFILEHELPER_H_INC
