assimp/code/Importer/IFC/IFCUtil.cpp

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

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  following disclaimer.

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*/

/** @file  IFCUtil.cpp
 *  @brief Implementation of conversion routines for some common Ifc helper entities.
 */



#ifndef ASSIMP_BUILD_NO_IFC_IMPORTER

#include "code/Importer/IFC/IFCUtil.h"
#include "code/PolyTools.h"
#include "code/ProcessHelper.h"
#include <assimp/Defines.h>

namespace Assimp {
    namespace IFC {

// ------------------------------------------------------------------------------------------------
void TempOpening::Transform(const IfcMatrix4& mat)
{
    if(profileMesh) {
        profileMesh->Transform(mat);
    }
    if(profileMesh2D) {
        profileMesh2D->Transform(mat);
    }
    extrusionDir *= IfcMatrix3(mat);
}

// ------------------------------------------------------------------------------------------------
aiMesh* TempMesh::ToMesh()
{
    ai_assert(mVerts.size() == std::accumulate(mVertcnt.begin(),mVertcnt.end(),size_t(0)));

    if (mVerts.empty()) {
        return NULL;
    }

    std::unique_ptr<aiMesh> mesh(new aiMesh());

    // copy vertices
    mesh->mNumVertices = static_cast<unsigned int>(mVerts.size());
    mesh->mVertices = new aiVector3D[mesh->mNumVertices];
    std::copy(mVerts.begin(),mVerts.end(),mesh->mVertices);

    // and build up faces
    mesh->mNumFaces = static_cast<unsigned int>(mVertcnt.size());
    mesh->mFaces = new aiFace[mesh->mNumFaces];

    for(unsigned int i = 0,n=0, acc = 0; i < mesh->mNumFaces; ++n) {
        aiFace& f = mesh->mFaces[i];
        if (!mVertcnt[n]) {
            --mesh->mNumFaces;
            continue;
        }

        f.mNumIndices = mVertcnt[n];
        f.mIndices = new unsigned int[f.mNumIndices];
        for(unsigned int a = 0; a < f.mNumIndices; ++a) {
            f.mIndices[a] = acc++;
        }

        ++i;
    }

    return mesh.release();
}

// ------------------------------------------------------------------------------------------------
void TempMesh::Clear()
{
    mVerts.clear();
    mVertcnt.clear();
}

// ------------------------------------------------------------------------------------------------
void TempMesh::Transform(const IfcMatrix4& mat)
{
    for(IfcVector3& v : mVerts) {
        v *= mat;
    }
}

// ------------------------------------------------------------------------------
IfcVector3 TempMesh::Center() const
{
    return (mVerts.size() == 0) ? IfcVector3(0.0f, 0.0f, 0.0f) : (std::accumulate(mVerts.begin(),mVerts.end(),IfcVector3()) / static_cast<IfcFloat>(mVerts.size()));
}

// ------------------------------------------------------------------------------------------------
void TempMesh::Append(const TempMesh& other)
{
    mVerts.insert(mVerts.end(),other.mVerts.begin(),other.mVerts.end());
    mVertcnt.insert(mVertcnt.end(),other.mVertcnt.begin(),other.mVertcnt.end());
}

// ------------------------------------------------------------------------------------------------
void TempMesh::RemoveDegenerates()
{
    // The strategy is simple: walk the mesh and compute normals using
    // Newell's algorithm. The length of the normals gives the area
    // of the polygons, which is close to zero for lines.

    std::vector<IfcVector3> normals;
    ComputePolygonNormals(normals, false);

    bool drop = false;
    size_t inor = 0;

    std::vector<IfcVector3>::iterator vit = mVerts.begin();
    for (std::vector<unsigned int>::iterator it = mVertcnt.begin(); it != mVertcnt.end(); ++inor) {
        const unsigned int pcount = *it;

        if (normals[inor].SquareLength() < 1e-10f) {
            it = mVertcnt.erase(it);
            vit = mVerts.erase(vit, vit + pcount);

            drop = true;
            continue;
        }

        vit += pcount;
        ++it;
    }

    if(drop) {
        IFCImporter::LogDebug("removing degenerate faces");
    }
}

// ------------------------------------------------------------------------------------------------
IfcVector3 TempMesh::ComputePolygonNormal(const IfcVector3* vtcs, size_t cnt, bool normalize)
{
    std::vector<IfcFloat> temp((cnt+2)*3);
    for( size_t vofs = 0, i = 0; vofs < cnt; ++vofs )
    {
        const IfcVector3& v = vtcs[vofs];
        temp[i++] = v.x;
        temp[i++] = v.y;
        temp[i++] = v.z;
    }

    IfcVector3 nor;
    NewellNormal<3, 3, 3>(nor, static_cast<int>(cnt), &temp[0], &temp[1], &temp[2]);
    return normalize ? nor.Normalize() : nor;
}

// ------------------------------------------------------------------------------------------------
void TempMesh::ComputePolygonNormals(std::vector<IfcVector3>& normals,
    bool normalize,
    size_t ofs) const
{
    size_t max_vcount = 0;
    std::vector<unsigned int>::const_iterator begin = mVertcnt.begin()+ofs, end = mVertcnt.end(),  iit;
    for(iit = begin; iit != end; ++iit) {
        max_vcount = std::max(max_vcount,static_cast<size_t>(*iit));
    }

    std::vector<IfcFloat> temp((max_vcount+2)*4);
    normals.reserve( normals.size() + mVertcnt.size()-ofs );

    // `NewellNormal()` currently has a relatively strange interface and need to
    // re-structure things a bit to meet them.
    size_t vidx = std::accumulate(mVertcnt.begin(),begin,0);
    for(iit = begin; iit != end; vidx += *iit++) {
        if (!*iit) {
            normals.push_back(IfcVector3());
            continue;
        }
        for(size_t vofs = 0, cnt = 0; vofs < *iit; ++vofs) {
            const IfcVector3& v = mVerts[vidx+vofs];
            temp[cnt++] = v.x;
            temp[cnt++] = v.y;
            temp[cnt++] = v.z;
#ifdef ASSIMP_BUILD_DEBUG
            temp[cnt] = std::numeric_limits<IfcFloat>::quiet_NaN();
#endif
            ++cnt;
        }

        normals.push_back(IfcVector3());
        NewellNormal<4,4,4>(normals.back(),*iit,&temp[0],&temp[1],&temp[2]);
    }

    if(normalize) {
        for(IfcVector3& n : normals) {
            n.Normalize();
        }
    }
}

// ------------------------------------------------------------------------------------------------
// Compute the normal of the last polygon in the given mesh
IfcVector3 TempMesh::ComputeLastPolygonNormal(bool normalize) const
{
    return ComputePolygonNormal(&mVerts[mVerts.size() - mVertcnt.back()], mVertcnt.back(), normalize);
}

struct CompareVector
{
    bool operator () (const IfcVector3& a, const IfcVector3& b) const
    {
        IfcVector3 d = a - b;
        IfcFloat eps = 1e-6;
        return d.x < -eps || (std::abs(d.x) < eps && d.y < -eps) || (std::abs(d.x) < eps && std::abs(d.y) < eps && d.z < -eps);
    }
};
struct FindVector
{
    IfcVector3 v;
    FindVector(const IfcVector3& p) : v(p) { }
    bool operator () (const IfcVector3& p) { return FuzzyVectorCompare(1e-6)(p, v); }
};

// ------------------------------------------------------------------------------------------------
void TempMesh::FixupFaceOrientation()
{
    const IfcVector3 vavg = Center();

    // create a list of start indices for all faces to allow random access to faces
    std::vector<size_t> faceStartIndices(mVertcnt.size());
    for( size_t i = 0, a = 0; a < mVertcnt.size(); i += mVertcnt[a], ++a )
        faceStartIndices[a] = i;

    // list all faces on a vertex
    std::map<IfcVector3, std::vector<size_t>, CompareVector> facesByVertex;
    for( size_t a = 0; a < mVertcnt.size(); ++a )
    {
        for( size_t b = 0; b < mVertcnt[a]; ++b )
            facesByVertex[mVerts[faceStartIndices[a] + b]].push_back(a);
    }
    // determine neighbourhood for all polys
    std::vector<size_t> neighbour(mVerts.size(), SIZE_MAX);
    std::vector<size_t> tempIntersect(10);
    for( size_t a = 0; a < mVertcnt.size(); ++a )
    {
        for( size_t b = 0; b < mVertcnt[a]; ++b )
        {
            size_t ib = faceStartIndices[a] + b, nib = faceStartIndices[a] + (b + 1) % mVertcnt[a];
            const std::vector<size_t>& facesOnB = facesByVertex[mVerts[ib]];
            const std::vector<size_t>& facesOnNB = facesByVertex[mVerts[nib]];
            // there should be exactly one or two faces which appear in both lists. Our face and the other side
            std::vector<size_t>::iterator sectstart = tempIntersect.begin();
            std::vector<size_t>::iterator sectend = std::set_intersection(
                facesOnB.begin(), facesOnB.end(), facesOnNB.begin(), facesOnNB.end(), sectstart);

            if( std::distance(sectstart, sectend) != 2 )
                continue;
            if( *sectstart == a )
                ++sectstart;
            neighbour[ib] = *sectstart;
        }
    }

    // now we're getting started. We take the face which is the farthest away from the center. This face is most probably
    // facing outwards. So we reverse this face to point outwards in relation to the center. Then we adapt neighbouring
    // faces to have the same winding until all faces have been tested.
    std::vector<bool> faceDone(mVertcnt.size(), false);
    while( std::count(faceDone.begin(), faceDone.end(), false) != 0 )
    {
        // find the farthest of the remaining faces
        size_t farthestIndex = SIZE_MAX;
        IfcFloat farthestDistance = -1.0;
        for( size_t a = 0; a < mVertcnt.size(); ++a )
        {
            if( faceDone[a] )
                continue;
            IfcVector3 faceCenter = std::accumulate(mVerts.begin() + faceStartIndices[a],
                mVerts.begin() + faceStartIndices[a] + mVertcnt[a], IfcVector3(0.0)) / IfcFloat(mVertcnt[a]);
            IfcFloat dst = (faceCenter - vavg).SquareLength();
            if( dst > farthestDistance ) { farthestDistance = dst; farthestIndex = a; }
        }

        // calculate its normal and reverse the poly if its facing towards the mesh center
        IfcVector3 farthestNormal = ComputePolygonNormal(mVerts.data() + faceStartIndices[farthestIndex], mVertcnt[farthestIndex]);
        IfcVector3 farthestCenter = std::accumulate(mVerts.begin() + faceStartIndices[farthestIndex],
            mVerts.begin() + faceStartIndices[farthestIndex] + mVertcnt[farthestIndex], IfcVector3(0.0))
            / IfcFloat(mVertcnt[farthestIndex]);
        // We accapt a bit of negative orientation without reversing. In case of doubt, prefer the orientation given in
        // the file.
        if( (farthestNormal * (farthestCenter - vavg).Normalize()) < -0.4 )
        {
            size_t fsi = faceStartIndices[farthestIndex], fvc = mVertcnt[farthestIndex];
            std::reverse(mVerts.begin() + fsi, mVerts.begin() + fsi + fvc);
            std::reverse(neighbour.begin() + fsi, neighbour.begin() + fsi + fvc);
            // because of the neighbour index belonging to the edge starting with the point at the same index, we need to
            // cycle the neighbours through to match the edges again.
            // Before: points A - B - C - D with edge neighbour p - q - r - s
            // After: points D - C - B - A, reversed neighbours are s - r - q - p, but the should be
            //                r   q   p   s
            for( size_t a = 0; a < fvc - 1; ++a )
                std::swap(neighbour[fsi + a], neighbour[fsi + a + 1]);
        }
        faceDone[farthestIndex] = true;
        std::vector<size_t> todo;
        todo.push_back(farthestIndex);

        // go over its neighbour faces recursively and adapt their winding order to match the farthest face
        while( !todo.empty() )
        {
            size_t tdf = todo.back();
            size_t vsi = faceStartIndices[tdf], vc = mVertcnt[tdf];
            todo.pop_back();

            // check its neighbours
            for( size_t a = 0; a < vc; ++a )
            {
                // ignore neighbours if we already checked them
                size_t nbi = neighbour[vsi + a];
                if( nbi == SIZE_MAX || faceDone[nbi] )
                    continue;

                const IfcVector3& vp = mVerts[vsi + a];
                size_t nbvsi = faceStartIndices[nbi], nbvc = mVertcnt[nbi];
                std::vector<IfcVector3>::iterator it = std::find_if(mVerts.begin() + nbvsi, mVerts.begin() + nbvsi + nbvc, FindVector(vp));
                ai_assert(it != mVerts.begin() + nbvsi + nbvc);
                size_t nb_vidx = std::distance(mVerts.begin() + nbvsi, it);
                // two faces winded in the same direction should have a crossed edge, where one face has p0->p1 and the other
                // has p1'->p0'. If the next point on the neighbouring face is also the next on the current face, we need
                // to reverse the neighbour
                nb_vidx = (nb_vidx + 1) % nbvc;
                size_t oursideidx = (a + 1) % vc;
                if( FuzzyVectorCompare(1e-6)(mVerts[vsi + oursideidx], mVerts[nbvsi + nb_vidx]) )
                {
                    std::reverse(mVerts.begin() + nbvsi, mVerts.begin() + nbvsi + nbvc);
                    std::reverse(neighbour.begin() + nbvsi, neighbour.begin() + nbvsi + nbvc);
                    for( size_t a = 0; a < nbvc - 1; ++a )
                        std::swap(neighbour[nbvsi + a], neighbour[nbvsi + a + 1]);
                }

                // either way we're done with the neighbour. Mark it as done and continue checking from there recursively
                faceDone[nbi] = true;
                todo.push_back(nbi);
            }
        }

        // no more faces reachable from this part of the surface, start over with a disjunct part and its farthest face
    }
}

// ------------------------------------------------------------------------------------------------
void TempMesh::RemoveAdjacentDuplicates() {
    bool drop = false;
    std::vector<IfcVector3>::iterator base = mVerts.begin();
    for(unsigned int& cnt : mVertcnt) {
        if (cnt < 2){
            base += cnt;
            continue;
        }

        IfcVector3 vmin,vmax;
        ArrayBounds(&*base, cnt ,vmin,vmax);


        const IfcFloat epsilon = (vmax-vmin).SquareLength() / static_cast<IfcFloat>(1e9);
        //const IfcFloat dotepsilon = 1e-9;

        //// look for vertices that lie directly on the line between their predecessor and their
        //// successor and replace them with either of them.

        //for(size_t i = 0; i < cnt; ++i) {
        //  IfcVector3& v1 = *(base+i), &v0 = *(base+(i?i-1:cnt-1)), &v2 = *(base+(i+1)%cnt);
        //  const IfcVector3& d0 = (v1-v0), &d1 = (v2-v1);
        //  const IfcFloat l0 = d0.SquareLength(), l1 = d1.SquareLength();
        //  if (!l0 || !l1) {
        //      continue;
        //  }

        //  const IfcFloat d = (d0/std::sqrt(l0))*(d1/std::sqrt(l1));

        //  if ( d >= 1.f-dotepsilon ) {
        //      v1 = v0;
        //  }
        //  else if ( d < -1.f+dotepsilon ) {
        //      v2 = v1;
        //      continue;
        //  }
        //}

        // drop any identical, adjacent vertices. this pass will collect the dropouts
        // of the previous pass as a side-effect.
        FuzzyVectorCompare fz(epsilon);
        std::vector<IfcVector3>::iterator end = base+cnt, e = std::unique( base, end, fz );
        if (e != end) {
            cnt -= static_cast<unsigned int>(std::distance(e, end));
            mVerts.erase(e,end);
            drop  = true;
        }

        // check front and back vertices for this polygon
        if (cnt > 1 && fz(*base,*(base+cnt-1))) {
            mVerts.erase(base+ --cnt);
            drop  = true;
        }

        // removing adjacent duplicates shouldn't erase everything :-)
        ai_assert(cnt>0);
        base += cnt;
    }
    if(drop) {
        IFCImporter::LogDebug("removing duplicate vertices");
    }
}

// ------------------------------------------------------------------------------------------------
void TempMesh::Swap(TempMesh& other)
{
    mVertcnt.swap(other.mVertcnt);
    mVerts.swap(other.mVerts);
}

// ------------------------------------------------------------------------------------------------
bool IsTrue(const ::Assimp::STEP::EXPRESS::BOOLEAN& in)
{
    return (std::string)in == "TRUE" || (std::string)in == "T";
}

// ------------------------------------------------------------------------------------------------
IfcFloat ConvertSIPrefix(const std::string& prefix)
{
    if (prefix == "EXA") {
        return 1e18f;
    }
    else if (prefix == "PETA") {
        return 1e15f;
    }
    else if (prefix == "TERA") {
        return 1e12f;
    }
    else if (prefix == "GIGA") {
        return 1e9f;
    }
    else if (prefix == "MEGA") {
        return 1e6f;
    }
    else if (prefix == "KILO") {
        return 1e3f;
    }
    else if (prefix == "HECTO") {
        return 1e2f;
    }
    else if (prefix == "DECA") {
        return 1e-0f;
    }
    else if (prefix == "DECI") {
        return 1e-1f;
    }
    else if (prefix == "CENTI") {
        return 1e-2f;
    }
    else if (prefix == "MILLI") {
        return 1e-3f;
    }
    else if (prefix == "MICRO") {
        return 1e-6f;
    }
    else if (prefix == "NANO") {
        return 1e-9f;
    }
    else if (prefix == "PICO") {
        return 1e-12f;
    }
    else if (prefix == "FEMTO") {
        return 1e-15f;
    }
    else if (prefix == "ATTO") {
        return 1e-18f;
    }
    else {
        IFCImporter::LogError("Unrecognized SI prefix: " + prefix);
        return 1;
    }
}

// ------------------------------------------------------------------------------------------------
void ConvertColor(aiColor4D& out, const Schema_2x3::IfcColourRgb& in)
{
    out.r = static_cast<float>( in.Red );
    out.g = static_cast<float>( in.Green );
    out.b = static_cast<float>( in.Blue );
    out.a = static_cast<float>( 1.f );
}

// ------------------------------------------------------------------------------------------------
void ConvertColor(aiColor4D& out, const Schema_2x3::IfcColourOrFactor& in,ConversionData& conv,const aiColor4D* base)
{
    if (const ::Assimp::STEP::EXPRESS::REAL* const r = in.ToPtr<::Assimp::STEP::EXPRESS::REAL>()) {
        out.r = out.g = out.b = static_cast<float>(*r);
        if(base) {
            out.r *= static_cast<float>( base->r );
            out.g *= static_cast<float>( base->g );
            out.b *= static_cast<float>( base->b );
            out.a = static_cast<float>( base->a );
        }
        else out.a = 1.0;
    }
    else if (const Schema_2x3::IfcColourRgb* const rgb = in.ResolveSelectPtr<Schema_2x3::IfcColourRgb>(conv.db)) {
        ConvertColor(out,*rgb);
    }
    else {
        IFCImporter::LogWarn("skipping unknown IfcColourOrFactor entity");
    }
}

// ------------------------------------------------------------------------------------------------
void ConvertCartesianPoint(IfcVector3& out, const Schema_2x3::IfcCartesianPoint& in)
{
    out = IfcVector3();
    for(size_t i = 0; i < in.Coordinates.size(); ++i) {
        out[static_cast<unsigned int>(i)] = in.Coordinates[i];
    }
}

// ------------------------------------------------------------------------------------------------
void ConvertVector(IfcVector3& out, const Schema_2x3::IfcVector& in)
{
    ConvertDirection(out,in.Orientation);
    out *= in.Magnitude;
}

// ------------------------------------------------------------------------------------------------
void ConvertDirection(IfcVector3& out, const Schema_2x3::IfcDirection& in)
{
    out = IfcVector3();
    for(size_t i = 0; i < in.DirectionRatios.size(); ++i) {
        out[static_cast<unsigned int>(i)] = in.DirectionRatios[i];
    }
    const IfcFloat len = out.Length();
    if (len<1e-6) {
        IFCImporter::LogWarn("direction vector magnitude too small, normalization would result in a division by zero");
        return;
    }
    out /= len;
}

// ------------------------------------------------------------------------------------------------
void AssignMatrixAxes(IfcMatrix4& out, const IfcVector3& x, const IfcVector3& y, const IfcVector3& z)
{
    out.a1 = x.x;
    out.b1 = x.y;
    out.c1 = x.z;

    out.a2 = y.x;
    out.b2 = y.y;
    out.c2 = y.z;

    out.a3 = z.x;
    out.b3 = z.y;
    out.c3 = z.z;
}

// ------------------------------------------------------------------------------------------------
void ConvertAxisPlacement(IfcMatrix4& out, const Schema_2x3::IfcAxis2Placement3D& in)
{
    IfcVector3 loc;
    ConvertCartesianPoint(loc,in.Location);

    IfcVector3 z(0.f,0.f,1.f),r(1.f,0.f,0.f),x;

    if (in.Axis) {
        ConvertDirection(z,*in.Axis.Get());
    }
    if (in.RefDirection) {
        ConvertDirection(r,*in.RefDirection.Get());
    }

    IfcVector3 v = r.Normalize();
    IfcVector3 tmpx = z * (v*z);

    x = (v-tmpx).Normalize();
    IfcVector3 y = (z^x);

    IfcMatrix4::Translation(loc,out);
    AssignMatrixAxes(out,x,y,z);
}

// ------------------------------------------------------------------------------------------------
void ConvertAxisPlacement(IfcMatrix4& out, const Schema_2x3::IfcAxis2Placement2D& in)
{
    IfcVector3 loc;
    ConvertCartesianPoint(loc,in.Location);

    IfcVector3 x(1.f,0.f,0.f);
    if (in.RefDirection) {
        ConvertDirection(x,*in.RefDirection.Get());
    }

    const IfcVector3 y = IfcVector3(x.y,-x.x,0.f);

    IfcMatrix4::Translation(loc,out);
    AssignMatrixAxes(out,x,y,IfcVector3(0.f,0.f,1.f));
}

// ------------------------------------------------------------------------------------------------
void ConvertAxisPlacement(IfcVector3& axis, IfcVector3& pos, const Schema_2x3::IfcAxis1Placement& in)
{
    ConvertCartesianPoint(pos,in.Location);
    if (in.Axis) {
        ConvertDirection(axis,in.Axis.Get());
    }
    else {
        axis = IfcVector3(0.f,0.f,1.f);
    }
}

// ------------------------------------------------------------------------------------------------
void ConvertAxisPlacement(IfcMatrix4& out, const Schema_2x3::IfcAxis2Placement& in, ConversionData& conv)
{
    if(const Schema_2x3::IfcAxis2Placement3D* pl3 = in.ResolveSelectPtr<Schema_2x3::IfcAxis2Placement3D>(conv.db)) {
        ConvertAxisPlacement(out,*pl3);
    }
    else if(const Schema_2x3::IfcAxis2Placement2D* pl2 = in.ResolveSelectPtr<Schema_2x3::IfcAxis2Placement2D>(conv.db)) {
        ConvertAxisPlacement(out,*pl2);
    }
    else {
        IFCImporter::LogWarn("skipping unknown IfcAxis2Placement entity");
    }
}

// ------------------------------------------------------------------------------------------------
void ConvertTransformOperator(IfcMatrix4& out, const Schema_2x3::IfcCartesianTransformationOperator& op)
{
    IfcVector3 loc;
    ConvertCartesianPoint(loc,op.LocalOrigin);

    IfcVector3 x(1.f,0.f,0.f),y(0.f,1.f,0.f),z(0.f,0.f,1.f);
    if (op.Axis1) {
        ConvertDirection(x,*op.Axis1.Get());
    }
    if (op.Axis2) {
        ConvertDirection(y,*op.Axis2.Get());
    }
    if (const Schema_2x3::IfcCartesianTransformationOperator3D* op2 = op.ToPtr<Schema_2x3::IfcCartesianTransformationOperator3D>()) {
        if(op2->Axis3) {
            ConvertDirection(z,*op2->Axis3.Get());
        }
    }

    IfcMatrix4 locm;
    IfcMatrix4::Translation(loc,locm);
    AssignMatrixAxes(out,x,y,z);


    IfcVector3 vscale;
    if (const Schema_2x3::IfcCartesianTransformationOperator3DnonUniform* nuni = op.ToPtr<Schema_2x3::IfcCartesianTransformationOperator3DnonUniform>()) {
        vscale.x = nuni->Scale?op.Scale.Get():1.f;
        vscale.y = nuni->Scale2?nuni->Scale2.Get():1.f;
        vscale.z = nuni->Scale3?nuni->Scale3.Get():1.f;
    }
    else {
        const IfcFloat sc = op.Scale?op.Scale.Get():1.f;
        vscale = IfcVector3(sc,sc,sc);
    }

    IfcMatrix4 s;
    IfcMatrix4::Scaling(vscale,s);

    out = locm * out * s;
}


} // ! IFC
} // ! Assimp

#endif