assimp.assimp/include/assimp/SmoothingGroups.h

/*
Open Asset Import Library (assimp)
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/** @file Defines the helper data structures for importing 3DS files.
http://www.jalix.org/ressources/graphics/3DS/_unofficials/3ds-unofficial.txt */

#pragma once
#ifndef AI_SMOOTHINGGROUPS_H_INC
#define AI_SMOOTHINGGROUPS_H_INC

#ifdef __GNUC__
#   pragma GCC system_header
#endif

#include <assimp/vector3.h>

#include <stdint.h>
#include <vector>

// ---------------------------------------------------------------------------
/** Helper structure representing a face with smoothing groups assigned */
struct FaceWithSmoothingGroup {
    FaceWithSmoothingGroup() AI_NO_EXCEPT
    : mIndices()
    , iSmoothGroup(0) {
        // in debug builds set all indices to a common magic value
#ifdef ASSIMP_BUILD_DEBUG
        this->mIndices[0] = 0xffffffff;
        this->mIndices[1] = 0xffffffff;
        this->mIndices[2] = 0xffffffff;
#endif
    }


    //! Indices. .3ds is using uint16. However, after
    //! an unique vertex set has been generated,
    //! individual index values might exceed 2^16
    uint32_t mIndices[3];

    //! specifies to which smoothing group the face belongs to
    uint32_t iSmoothGroup;
};

// ---------------------------------------------------------------------------
/** Helper structure representing a mesh whose faces have smoothing
    groups assigned. This allows us to reuse the code for normal computations
    from smoothings groups for several loaders (3DS, ASE). All of them
    use face structures which inherit from #FaceWithSmoothingGroup,
    but as they add extra members and need to be copied by value we
    need to use a template here.
    */
template <class T>
struct MeshWithSmoothingGroups
{
    //! Vertex positions
    std::vector<aiVector3D> mPositions;

    //! Face lists
    std::vector<T> mFaces;

    //! List of normal vectors
    std::vector<aiVector3D> mNormals;
};

// ---------------------------------------------------------------------------
/** Computes normal vectors for the mesh
 */
template <class T>
void ComputeNormalsWithSmoothingsGroups(MeshWithSmoothingGroups<T>& sMesh);


// include implementations
#include "SmoothingGroups.inl"

#endif // !! AI_SMOOTHINGGROUPS_H_INC