assimp/code/Ply/PlyLoader.cpp

/*
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*/

/** @file  PlyLoader.cpp
 *  @brief Implementation of the PLY importer class
 */

#ifndef ASSIMP_BUILD_NO_PLY_IMPORTER

// internal headers
#include "PlyLoader.h"
#include <assimp/IOStreamBuffer.h>
#include <assimp/Macros.h>
#include <memory>
#include <assimp/IOSystem.hpp>
#include <assimp/scene.h>
#include <assimp/importerdesc.h>

using namespace ::Assimp;

static const aiImporterDesc desc = {
    "Stanford Polygon Library (PLY) Importer",
    "",
    "",
    "",
    aiImporterFlags_SupportBinaryFlavour | aiImporterFlags_SupportTextFlavour,
    0,
    0,
    0,
    0,
    "ply"
};


// ------------------------------------------------------------------------------------------------
// Internal stuff
namespace {
    // ------------------------------------------------------------------------------------------------
    // Checks that property index is within range
    template <class T>
    inline
    const T &GetProperty(const std::vector<T> &props, int idx) {
        if (static_cast<size_t>(idx) >= props.size()) {
            throw DeadlyImportError("Invalid .ply file: Property index is out of range.");
        }

        return props[idx];
    }
}

// ------------------------------------------------------------------------------------------------
// Constructor to be privately used by Importer
PLYImporter::PLYImporter()
: mBuffer(nullptr)
, pcDOM(nullptr)
, mGeneratedMesh(nullptr) {
    // empty
}

// ------------------------------------------------------------------------------------------------
// Destructor, private as well
PLYImporter::~PLYImporter() {
    // empty
}

// ------------------------------------------------------------------------------------------------
// Returns whether the class can handle the format of the given file.
bool PLYImporter::CanRead(const std::string& pFile, IOSystem* pIOHandler, bool checkSig) const {
    const std::string extension = GetExtension(pFile);

    if ( extension == "ply" ) {
        return true;
    } else if (!extension.length() || checkSig) {
        if ( !pIOHandler ) {
            return true;
        }
        static const char* tokens[] = { "ply" };
        return SearchFileHeaderForToken(pIOHandler, pFile, tokens, 1);
    }

    return false;
}

// ------------------------------------------------------------------------------------------------
const aiImporterDesc* PLYImporter::GetInfo() const {
    return &desc;
}

// ------------------------------------------------------------------------------------------------
static bool isBigEndian(const char* szMe) {
    ai_assert(nullptr != szMe);

    // binary_little_endian
    // binary_big_endian
    bool isBigEndian(false);
#if (defined AI_BUILD_BIG_ENDIAN)
    if ( 'l' == *szMe || 'L' == *szMe ) {
        isBigEndian = true;
    }
#else
    if ('b' == *szMe || 'B' == *szMe) {
        isBigEndian = true;
    }
#endif // ! AI_BUILD_BIG_ENDIAN

    return isBigEndian;
}

// ------------------------------------------------------------------------------------------------
// Imports the given file into the given scene structure.
void PLYImporter::InternReadFile(const std::string& pFile, aiScene* pScene, IOSystem* pIOHandler) {
    const std::string mode = "rb";
    std::unique_ptr<IOStream> fileStream(pIOHandler->Open(pFile, mode));
    if (!fileStream.get()) {
        throw DeadlyImportError("Failed to open file " + pFile + ".");
    }

    // Get the file-size
    const size_t fileSize( fileStream->FileSize() );
    if ( 0 == fileSize ) {
        throw DeadlyImportError("File " + pFile + " is empty.");
    }

    IOStreamBuffer<char> streamedBuffer(1024 * 1024);
    streamedBuffer.open(fileStream.get());

    // the beginning of the file must be PLY - magic, magic
    std::vector<char> headerCheck;
    streamedBuffer.getNextLine(headerCheck);

    if ((headerCheck.size() < 3) ||
            (headerCheck[0] != 'P' && headerCheck[0] != 'p') ||
            (headerCheck[1] != 'L' && headerCheck[1] != 'l') ||
            (headerCheck[2] != 'Y' && headerCheck[2] != 'y') ) {
        streamedBuffer.close();
        throw DeadlyImportError("Invalid .ply file: Magic number \'ply\' is no there");
    }

    std::vector<char> mBuffer2;
    streamedBuffer.getNextLine(mBuffer2);
    mBuffer = (unsigned char*)&mBuffer2[0];

    char* szMe = (char*)&this->mBuffer[0];
    SkipSpacesAndLineEnd(szMe, (const char**)&szMe);

    // determine the format of the file data and construct the aiMesh
    PLY::DOM sPlyDom;   
    this->pcDOM = &sPlyDom;

    if (TokenMatch(szMe, "format", 6)) {
        if (TokenMatch(szMe, "ascii", 5)) {
            SkipLine(szMe, (const char**)&szMe);
            if (!PLY::DOM::ParseInstance(streamedBuffer, &sPlyDom, this)) {
                if (mGeneratedMesh != nullptr) {
                    delete(mGeneratedMesh);
                    mGeneratedMesh = nullptr;
                }

                streamedBuffer.close();
                throw DeadlyImportError("Invalid .ply file: Unable to build DOM (#1)");
            }
        } else if (!::strncmp(szMe, "binary_", 7)) {
            szMe += 7;
            const bool bIsBE(isBigEndian(szMe));

            // skip the line, parse the rest of the header and build the DOM
            if (!PLY::DOM::ParseInstanceBinary(streamedBuffer, &sPlyDom, this, bIsBE)) {
                if (mGeneratedMesh != nullptr) {
                    delete(mGeneratedMesh);
                    mGeneratedMesh = nullptr;
                }

                streamedBuffer.close();
                throw DeadlyImportError("Invalid .ply file: Unable to build DOM (#2)");
            }
        } else {
            if (mGeneratedMesh != nullptr) {
                delete(mGeneratedMesh);
                mGeneratedMesh = nullptr;
            }

            streamedBuffer.close();
            throw DeadlyImportError("Invalid .ply file: Unknown file format");
        }
    } else {
        AI_DEBUG_INVALIDATE_PTR(this->mBuffer);
        if (mGeneratedMesh != nullptr) {
            delete(mGeneratedMesh);
            mGeneratedMesh = nullptr;
        }

        streamedBuffer.close();
        throw DeadlyImportError("Invalid .ply file: Missing format specification");
    }

    //free the file buffer
    streamedBuffer.close();

    if (mGeneratedMesh == nullptr) {
        throw DeadlyImportError("Invalid .ply file: Unable to extract mesh data ");
    }

    // if no face list is existing we assume that the vertex
    // list is containing a list of points
    bool pointsOnly = mGeneratedMesh->mFaces == nullptr ? true : false;
    if (pointsOnly) {
      mGeneratedMesh->mPrimitiveTypes = aiPrimitiveType::aiPrimitiveType_POINT;
    }

    // now load a list of all materials
    std::vector<aiMaterial*> avMaterials;
    std::string defaultTexture;
    LoadMaterial(&avMaterials, defaultTexture, pointsOnly);

    // now generate the output scene object. Fill the material list
    pScene->mNumMaterials = (unsigned int)avMaterials.size();
    pScene->mMaterials = new aiMaterial*[pScene->mNumMaterials];
    for (unsigned int i = 0; i < pScene->mNumMaterials; ++i) {
        pScene->mMaterials[i] = avMaterials[i];
    }

    // fill the mesh list
    pScene->mNumMeshes = 1;
    pScene->mMeshes = new aiMesh*[pScene->mNumMeshes];
    pScene->mMeshes[0] = mGeneratedMesh;
    mGeneratedMesh = nullptr;

    // generate a simple node structure
    pScene->mRootNode = new aiNode();
    pScene->mRootNode->mNumMeshes = pScene->mNumMeshes;
    pScene->mRootNode->mMeshes = new unsigned int[pScene->mNumMeshes];

    for (unsigned int i = 0; i < pScene->mRootNode->mNumMeshes; ++i) {
        pScene->mRootNode->mMeshes[i] = i;
    }
}

void PLYImporter::LoadVertex(const PLY::Element* pcElement, const PLY::ElementInstance* instElement, unsigned int pos) {
    ai_assert(nullptr != pcElement);
    ai_assert(nullptr != instElement);

    ai_uint aiPositions[3] = { 0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF };
    PLY::EDataType aiTypes[3] = { EDT_Char, EDT_Char, EDT_Char };

    ai_uint aiNormal[3] = { 0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF };
    PLY::EDataType aiNormalTypes[3] = { EDT_Char, EDT_Char, EDT_Char };

    unsigned int aiColors[4] = { 0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF };
    PLY::EDataType aiColorsTypes[4] = { EDT_Char, EDT_Char, EDT_Char, EDT_Char };

    unsigned int aiTexcoord[2] = { 0xFFFFFFFF, 0xFFFFFFFF };
    PLY::EDataType aiTexcoordTypes[2] = { EDT_Char, EDT_Char };

    // now check whether which normal components are available
    unsigned int _a( 0 ), cnt( 0 );
    for ( std::vector<PLY::Property>::const_iterator a = pcElement->alProperties.begin();
            a != pcElement->alProperties.end(); ++a, ++_a) {
        if ((*a).bIsList) {
            continue;
        }

        // Positions
        if (PLY::EST_XCoord == (*a).Semantic) {
            ++cnt;
            aiPositions[0] = _a;
            aiTypes[0] = (*a).eType;
        } else if (PLY::EST_YCoord == (*a).Semantic) {
            ++cnt;
            aiPositions[1] = _a;
            aiTypes[1] = (*a).eType;
        } else if (PLY::EST_ZCoord == (*a).Semantic) {
            ++cnt;
            aiPositions[2] = _a;
            aiTypes[2] = (*a).eType;
        } else if (PLY::EST_XNormal == (*a).Semantic) {
            // Normals
            ++cnt;
            aiNormal[0] = _a;
            aiNormalTypes[0] = (*a).eType;
        } else if (PLY::EST_YNormal == (*a).Semantic) {
            ++cnt;
            aiNormal[1] = _a;
            aiNormalTypes[1] = (*a).eType;
        } else if (PLY::EST_ZNormal == (*a).Semantic) {
            ++cnt;
            aiNormal[2] = _a;
            aiNormalTypes[2] = (*a).eType;
        } else if (PLY::EST_Red == (*a).Semantic) {
            // Colors
            ++cnt;
            aiColors[0] = _a;
            aiColorsTypes[0] = (*a).eType;
        } else if (PLY::EST_Green == (*a).Semantic) {
            ++cnt;
            aiColors[1] = _a;
            aiColorsTypes[1] = (*a).eType;
        } else if (PLY::EST_Blue == (*a).Semantic) {
            ++cnt;
            aiColors[2] = _a;
            aiColorsTypes[2] = (*a).eType;
        } else if (PLY::EST_Alpha == (*a).Semantic) {
            ++cnt;
            aiColors[3] = _a;
            aiColorsTypes[3] = (*a).eType;
        } else if (PLY::EST_UTextureCoord == (*a).Semantic) {
            // Texture coordinates
            ++cnt;
            aiTexcoord[0] = _a;
            aiTexcoordTypes[0] = (*a).eType;
        } else if (PLY::EST_VTextureCoord == (*a).Semantic) {
            ++cnt;
            aiTexcoord[1] = _a;
            aiTexcoordTypes[1] = (*a).eType;
        }
    }

    // check whether we have a valid source for the vertex data
    if (0 != cnt) {
        // Position
        aiVector3D vOut;
        if (0xFFFFFFFF != aiPositions[0]) {
            vOut.x = PLY::PropertyInstance::ConvertTo<ai_real>(
                GetProperty(instElement->alProperties, aiPositions[0]).avList.front(), aiTypes[0]);
        }

        if (0xFFFFFFFF != aiPositions[1]) {
            vOut.y = PLY::PropertyInstance::ConvertTo<ai_real>(
                GetProperty(instElement->alProperties, aiPositions[1]).avList.front(), aiTypes[1]);
        }

        if (0xFFFFFFFF != aiPositions[2]) {
            vOut.z = PLY::PropertyInstance::ConvertTo<ai_real>(
                GetProperty(instElement->alProperties, aiPositions[2]).avList.front(), aiTypes[2]);
        }

        // Normals
        aiVector3D nOut;
        bool haveNormal = false;
        if (0xFFFFFFFF != aiNormal[0]) {
            nOut.x = PLY::PropertyInstance::ConvertTo<ai_real>(
                GetProperty(instElement->alProperties, aiNormal[0]).avList.front(), aiNormalTypes[0]);
            haveNormal = true;
        }

        if (0xFFFFFFFF != aiNormal[1]) {
            nOut.y = PLY::PropertyInstance::ConvertTo<ai_real>(
                GetProperty(instElement->alProperties, aiNormal[1]).avList.front(), aiNormalTypes[1]);
            haveNormal = true;
        }

        if (0xFFFFFFFF != aiNormal[2]) {
            nOut.z = PLY::PropertyInstance::ConvertTo<ai_real>(
                GetProperty(instElement->alProperties, aiNormal[2]).avList.front(), aiNormalTypes[2]);
            haveNormal = true;
        }

        //Colors
        aiColor4D cOut;
        bool haveColor = false;
        if (0xFFFFFFFF != aiColors[0]) {
            cOut.r = NormalizeColorValue(GetProperty(instElement->alProperties,
                aiColors[0]).avList.front(), aiColorsTypes[0]);
            haveColor = true;
        }

        if (0xFFFFFFFF != aiColors[1]) {
            cOut.g = NormalizeColorValue(GetProperty(instElement->alProperties,
                aiColors[1]).avList.front(), aiColorsTypes[1]);
            haveColor = true;
        }

        if (0xFFFFFFFF != aiColors[2]) {
            cOut.b = NormalizeColorValue(GetProperty(instElement->alProperties,
                aiColors[2]).avList.front(), aiColorsTypes[2]);
            haveColor = true;
        }

        // assume 1.0 for the alpha channel if it is not set
        if (0xFFFFFFFF == aiColors[3]) {
            cOut.a = 1.0;
        } else {
            cOut.a = NormalizeColorValue(GetProperty(instElement->alProperties,
                aiColors[3]).avList.front(), aiColorsTypes[3]);

            haveColor = true;
        }

        //Texture coordinates
        aiVector3D tOut;
        tOut.z = 0;
        bool haveTextureCoords = false;
        if (0xFFFFFFFF != aiTexcoord[0]) {
            tOut.x = PLY::PropertyInstance::ConvertTo<ai_real>(
                GetProperty(instElement->alProperties, aiTexcoord[0]).avList.front(), aiTexcoordTypes[0]);
            haveTextureCoords = true;
        }

        if (0xFFFFFFFF != aiTexcoord[1]) {
            tOut.y = PLY::PropertyInstance::ConvertTo<ai_real>(
                GetProperty(instElement->alProperties, aiTexcoord[1]).avList.front(), aiTexcoordTypes[1]);
            haveTextureCoords = true;
        }

        //create aiMesh if needed
        if ( nullptr == mGeneratedMesh ) {
            mGeneratedMesh = new aiMesh();
            mGeneratedMesh->mMaterialIndex = 0;
        }

        if (nullptr == mGeneratedMesh->mVertices) {
            mGeneratedMesh->mNumVertices = pcElement->NumOccur;
            mGeneratedMesh->mVertices = new aiVector3D[mGeneratedMesh->mNumVertices];
        }

        mGeneratedMesh->mVertices[pos] = vOut;

        if (haveNormal) {
            if (nullptr == mGeneratedMesh->mNormals)
                mGeneratedMesh->mNormals = new aiVector3D[mGeneratedMesh->mNumVertices];
            mGeneratedMesh->mNormals[pos] = nOut;
        }

        if (haveColor) {
            if (nullptr == mGeneratedMesh->mColors[0])
                mGeneratedMesh->mColors[0] = new aiColor4D[mGeneratedMesh->mNumVertices];
            mGeneratedMesh->mColors[0][pos] = cOut;
        }

        if (haveTextureCoords) {
            if (nullptr == mGeneratedMesh->mTextureCoords[0]) {
                mGeneratedMesh->mNumUVComponents[0] = 2;
                mGeneratedMesh->mTextureCoords[0] = new aiVector3D[mGeneratedMesh->mNumVertices];
            }
            mGeneratedMesh->mTextureCoords[0][pos] = tOut;
        }
    }
}


// ------------------------------------------------------------------------------------------------
// Convert a color component to [0...1]
ai_real PLYImporter::NormalizeColorValue(PLY::PropertyInstance::ValueUnion val, PLY::EDataType eType) {
    switch (eType) {
        case EDT_Float:
            return val.fFloat;
        case EDT_Double:
            return (ai_real)val.fDouble;
        case EDT_UChar:
            return (ai_real)val.iUInt / (ai_real)0xFF;
        case EDT_Char:
            return (ai_real)(val.iInt + (0xFF / 2)) / (ai_real)0xFF;
        case EDT_UShort:
            return (ai_real)val.iUInt / (ai_real)0xFFFF;
        case EDT_Short:
            return (ai_real)(val.iInt + (0xFFFF / 2)) / (ai_real)0xFFFF;
        case EDT_UInt:
            return (ai_real)val.iUInt / (ai_real)0xFFFF;
        case EDT_Int:
            return ((ai_real)val.iInt / (ai_real)0xFF) + 0.5f;
        default:
            break;
    }

    return 0.0f;
}

// ------------------------------------------------------------------------------------------------
// Try to extract proper faces from the PLY DOM
void PLYImporter::LoadFace(const PLY::Element* pcElement, const PLY::ElementInstance* instElement,
        unsigned int pos) {
    ai_assert(nullptr != pcElement);
    ai_assert(nullptr != instElement);

    if (mGeneratedMesh == nullptr) {
        throw DeadlyImportError("Invalid .ply file: Vertices should be declared before faces");
    }

    bool bOne = false;

    // index of the vertex index list
    unsigned int iProperty = 0xFFFFFFFF;
    PLY::EDataType eType = EDT_Char;
    bool bIsTriStrip = false;

    // index of the material index property
    //unsigned int iMaterialIndex = 0xFFFFFFFF;
    //PLY::EDataType eType2 = EDT_Char;

    // texture coordinates
    unsigned int iTextureCoord = 0xFFFFFFFF;
    PLY::EDataType eType3 = EDT_Char;

    // face = unique number of vertex indices
    if (PLY::EEST_Face == pcElement->eSemantic) {
        unsigned int _a = 0;
        for (std::vector<PLY::Property>::const_iterator a = pcElement->alProperties.begin();
                a != pcElement->alProperties.end(); ++a, ++_a) {
            if (PLY::EST_VertexIndex == (*a).Semantic) {
                // must be a dynamic list!
                if (!(*a).bIsList) {
                    continue;
                }

                iProperty = _a;
                bOne = true;
                eType = (*a).eType;
            } else if (PLY::EST_TextureCoordinates == (*a).Semantic) {
                // must be a dynamic list!
                if (!(*a).bIsList) {
                    continue;
                }
                iTextureCoord = _a;
                bOne = true;
                eType3 = (*a).eType;
            }
        }
    }
    // triangle strip
    // TODO: triangle strip and material index support???
    else if (PLY::EEST_TriStrip == pcElement->eSemantic) {
        unsigned int _a = 0;
        for (std::vector<PLY::Property>::const_iterator a = pcElement->alProperties.begin();
                a != pcElement->alProperties.end(); ++a, ++_a) {
            // must be a dynamic list!
            if (!(*a).bIsList) {
                continue;
            }
            iProperty = _a;
            bOne = true;
            bIsTriStrip = true;
            eType = (*a).eType;
            break;
        }
    }

    // check whether we have at least one per-face information set
    if (bOne) {
        if (mGeneratedMesh->mFaces == nullptr) {
            mGeneratedMesh->mNumFaces = pcElement->NumOccur;
            mGeneratedMesh->mFaces = new aiFace[mGeneratedMesh->mNumFaces];
        }

        if (!bIsTriStrip) {
            // parse the list of vertex indices
            if (0xFFFFFFFF != iProperty) {
                const unsigned int iNum = (unsigned int)GetProperty(instElement->alProperties, iProperty).avList.size();
                mGeneratedMesh->mFaces[pos].mNumIndices = iNum;
                mGeneratedMesh->mFaces[pos].mIndices = new unsigned int[iNum];

                std::vector<PLY::PropertyInstance::ValueUnion>::const_iterator p =
                GetProperty(instElement->alProperties, iProperty).avList.begin();

                for (unsigned int a = 0; a < iNum; ++a, ++p) {
                    mGeneratedMesh->mFaces[pos].mIndices[a] = PLY::PropertyInstance::ConvertTo<unsigned int>(*p, eType);
                }
            }

        // parse the material index
        // cannot be handled without processing the whole file first
        /*if (0xFFFFFFFF != iMaterialIndex)
        {
            mGeneratedMesh->mFaces[pos]. = PLY::PropertyInstance::ConvertTo<unsigned int>(
            GetProperty(instElement->alProperties, iMaterialIndex).avList.front(), eType2);
        }*/

            if (0xFFFFFFFF != iTextureCoord) {
                const unsigned int iNum = (unsigned int)GetProperty(instElement->alProperties, iTextureCoord).avList.size();

                //should be 6 coords
                std::vector<PLY::PropertyInstance::ValueUnion>::const_iterator p =
                GetProperty(instElement->alProperties, iTextureCoord).avList.begin();

                if ((iNum / 3) == 2) // X Y coord
                {
                    for (unsigned int a = 0; a < iNum; ++a, ++p) {
                        unsigned int vindex = mGeneratedMesh->mFaces[pos].mIndices[a / 2];
                        if (vindex < mGeneratedMesh->mNumVertices) {
                            if (mGeneratedMesh->mTextureCoords[0] == nullptr ) {
                                mGeneratedMesh->mNumUVComponents[0] = 2;
                                mGeneratedMesh->mTextureCoords[0] = new aiVector3D[mGeneratedMesh->mNumVertices];
                            }

                            if (a % 2 == 0) {
                                mGeneratedMesh->mTextureCoords[0][vindex].x = PLY::PropertyInstance::ConvertTo<ai_real>(*p, eType3);
                            } else {
                                mGeneratedMesh->mTextureCoords[0][vindex].y = PLY::PropertyInstance::ConvertTo<ai_real>(*p, eType3);
                            }

                            mGeneratedMesh->mTextureCoords[0][vindex].z = 0;
                        }
                    }
                }
            }
        } else { // triangle strips
            // normally we have only one triangle strip instance where
            // a value of -1 indicates a restart of the strip
            bool flip = false;
            const std::vector<PLY::PropertyInstance::ValueUnion>& quak = GetProperty(instElement->alProperties, iProperty).avList;
            //pvOut->reserve(pvOut->size() + quak.size() + (quak.size()>>2u)); //Limits memory consumption

            int aiTable[2] = { -1, -1 };
            for (std::vector<PLY::PropertyInstance::ValueUnion>::const_iterator a = quak.begin(); a != quak.end(); ++a)  {
                const int p = PLY::PropertyInstance::ConvertTo<int>(*a, eType);

                if (-1 == p) {
                    // restart the strip ...
                    aiTable[0] = aiTable[1] = -1;
                    flip = false;
                    continue;
                }
                if (-1 == aiTable[0]) {
                    aiTable[0] = p;
                    continue;
                }
                if (-1 == aiTable[1]) {
                    aiTable[1] = p;
                    continue;
                }

                if (mGeneratedMesh->mFaces == nullptr) {
                    mGeneratedMesh->mNumFaces = pcElement->NumOccur;
                    mGeneratedMesh->mFaces = new aiFace[mGeneratedMesh->mNumFaces];
                }

                mGeneratedMesh->mFaces[pos].mNumIndices = 3;
                mGeneratedMesh->mFaces[pos].mIndices = new unsigned int[3];
                mGeneratedMesh->mFaces[pos].mIndices[0] = aiTable[0];
                mGeneratedMesh->mFaces[pos].mIndices[1] = aiTable[1];
                mGeneratedMesh->mFaces[pos].mIndices[2] = p;

                // every second pass swap the indices.
                flip = !flip;
                if ( flip ) {
                    std::swap(mGeneratedMesh->mFaces[pos].mIndices[0], mGeneratedMesh->mFaces[pos].mIndices[1]);
                }

                aiTable[0] = aiTable[1];
                aiTable[1] = p;
            }
        }
    }
}

// ------------------------------------------------------------------------------------------------
// Get a RGBA color in [0...1] range
void PLYImporter::GetMaterialColor(const std::vector<PLY::PropertyInstance>& avList,
  unsigned int aiPositions[4],
  PLY::EDataType aiTypes[4],
  aiColor4D* clrOut)
{
  ai_assert(NULL != clrOut);

  if (0xFFFFFFFF == aiPositions[0])clrOut->r = 0.0f;
  else
  {
    clrOut->r = NormalizeColorValue(GetProperty(avList,
      aiPositions[0]).avList.front(), aiTypes[0]);
  }

  if (0xFFFFFFFF == aiPositions[1])clrOut->g = 0.0f;
  else
  {
    clrOut->g = NormalizeColorValue(GetProperty(avList,
      aiPositions[1]).avList.front(), aiTypes[1]);
  }

  if (0xFFFFFFFF == aiPositions[2])clrOut->b = 0.0f;
  else
  {
    clrOut->b = NormalizeColorValue(GetProperty(avList,
      aiPositions[2]).avList.front(), aiTypes[2]);
  }

  // assume 1.0 for the alpha channel ifit is not set
  if (0xFFFFFFFF == aiPositions[3])clrOut->a = 1.0f;
  else
  {
    clrOut->a = NormalizeColorValue(GetProperty(avList,
      aiPositions[3]).avList.front(), aiTypes[3]);
  }
}

// ------------------------------------------------------------------------------------------------
// Extract a material from the PLY DOM
void PLYImporter::LoadMaterial(std::vector<aiMaterial*>* pvOut, std::string &defaultTexture, const bool pointsOnly)
{
  ai_assert(NULL != pvOut);

  // diffuse[4], specular[4], ambient[4]
  // rgba order
  unsigned int aaiPositions[3][4] = {

    { 0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF },
    { 0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF },
    { 0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF },
  };

  PLY::EDataType aaiTypes[3][4] = {
    { EDT_Char, EDT_Char, EDT_Char, EDT_Char },
    { EDT_Char, EDT_Char, EDT_Char, EDT_Char },
    { EDT_Char, EDT_Char, EDT_Char, EDT_Char }
  };
  PLY::ElementInstanceList* pcList = NULL;

  unsigned int iPhong = 0xFFFFFFFF;
  PLY::EDataType ePhong = EDT_Char;

  unsigned int iOpacity = 0xFFFFFFFF;
  PLY::EDataType eOpacity = EDT_Char;

  // search in the DOM for a vertex entry
  unsigned int _i = 0;
  for (std::vector<PLY::Element>::const_iterator i = this->pcDOM->alElements.begin();
    i != this->pcDOM->alElements.end(); ++i, ++_i)
  {
    if (PLY::EEST_Material == (*i).eSemantic)
    {
      pcList = &this->pcDOM->alElementData[_i];

      // now check whether which coordinate sets are available
      unsigned int _a = 0;
      for (std::vector<PLY::Property>::const_iterator
        a = (*i).alProperties.begin();
        a != (*i).alProperties.end(); ++a, ++_a)
      {
        if ((*a).bIsList)continue;

        // pohng specularity      -----------------------------------
        if (PLY::EST_PhongPower == (*a).Semantic)
        {
          iPhong = _a;
          ePhong = (*a).eType;
        }

        // general opacity        -----------------------------------
        if (PLY::EST_Opacity == (*a).Semantic)
        {
          iOpacity = _a;
          eOpacity = (*a).eType;
        }

        // diffuse color channels -----------------------------------
        if (PLY::EST_DiffuseRed == (*a).Semantic)
        {
          aaiPositions[0][0] = _a;
          aaiTypes[0][0] = (*a).eType;
        }
        else if (PLY::EST_DiffuseGreen == (*a).Semantic)
        {
          aaiPositions[0][1] = _a;
          aaiTypes[0][1] = (*a).eType;
        }
        else if (PLY::EST_DiffuseBlue == (*a).Semantic)
        {
          aaiPositions[0][2] = _a;
          aaiTypes[0][2] = (*a).eType;
        }
        else if (PLY::EST_DiffuseAlpha == (*a).Semantic)
        {
          aaiPositions[0][3] = _a;
          aaiTypes[0][3] = (*a).eType;
        }
        // specular color channels -----------------------------------
        else if (PLY::EST_SpecularRed == (*a).Semantic)
        {
          aaiPositions[1][0] = _a;
          aaiTypes[1][0] = (*a).eType;
        }
        else if (PLY::EST_SpecularGreen == (*a).Semantic)
        {
          aaiPositions[1][1] = _a;
          aaiTypes[1][1] = (*a).eType;
        }
        else if (PLY::EST_SpecularBlue == (*a).Semantic)
        {
          aaiPositions[1][2] = _a;
          aaiTypes[1][2] = (*a).eType;
        }
        else if (PLY::EST_SpecularAlpha == (*a).Semantic)
        {
          aaiPositions[1][3] = _a;
          aaiTypes[1][3] = (*a).eType;
        }
        // ambient color channels -----------------------------------
        else if (PLY::EST_AmbientRed == (*a).Semantic)
        {
          aaiPositions[2][0] = _a;
          aaiTypes[2][0] = (*a).eType;
        }
        else if (PLY::EST_AmbientGreen == (*a).Semantic)
        {
          aaiPositions[2][1] = _a;
          aaiTypes[2][1] = (*a).eType;
        }
        else if (PLY::EST_AmbientBlue == (*a).Semantic)
        {
          aaiPositions[2][2] = _a;
          aaiTypes[2][2] = (*a).eType;
        }
        else if (PLY::EST_AmbientAlpha == (*a).Semantic)
        {
          aaiPositions[2][3] = _a;
          aaiTypes[2][3] = (*a).eType;
        }
      }
      break;
    }
    else if (PLY::EEST_TextureFile == (*i).eSemantic)
    {
      defaultTexture = (*i).szName;
    }
  }
  // check whether we have a valid source for the material data
  if (NULL != pcList) {
    for (std::vector<ElementInstance>::const_iterator i = pcList->alInstances.begin(); i != pcList->alInstances.end(); ++i)  {
      aiColor4D clrOut;
      aiMaterial* pcHelper = new aiMaterial();

      // build the diffuse material color
      GetMaterialColor((*i).alProperties, aaiPositions[0], aaiTypes[0], &clrOut);
      pcHelper->AddProperty<aiColor4D>(&clrOut, 1, AI_MATKEY_COLOR_DIFFUSE);

      // build the specular material color
      GetMaterialColor((*i).alProperties, aaiPositions[1], aaiTypes[1], &clrOut);
      pcHelper->AddProperty<aiColor4D>(&clrOut, 1, AI_MATKEY_COLOR_SPECULAR);

      // build the ambient material color
      GetMaterialColor((*i).alProperties, aaiPositions[2], aaiTypes[2], &clrOut);
      pcHelper->AddProperty<aiColor4D>(&clrOut, 1, AI_MATKEY_COLOR_AMBIENT);

      // handle phong power and shading mode
      int iMode = (int)aiShadingMode_Gouraud;
      if (0xFFFFFFFF != iPhong)   {
        ai_real fSpec = PLY::PropertyInstance::ConvertTo<ai_real>(GetProperty((*i).alProperties, iPhong).avList.front(), ePhong);

        // if shininess is 0 (and the pow() calculation would therefore always
        // become 1, not depending on the angle), use gouraud lighting
        if (fSpec)  {
          // scale this with 15 ... hopefully this is correct
          fSpec *= 15;
          pcHelper->AddProperty<ai_real>(&fSpec, 1, AI_MATKEY_SHININESS);

          iMode = (int)aiShadingMode_Phong;
        }
      }
      pcHelper->AddProperty<int>(&iMode, 1, AI_MATKEY_SHADING_MODEL);

      // handle opacity
      if (0xFFFFFFFF != iOpacity) {
        ai_real fOpacity = PLY::PropertyInstance::ConvertTo<ai_real>(GetProperty((*i).alProperties, iPhong).avList.front(), eOpacity);
        pcHelper->AddProperty<ai_real>(&fOpacity, 1, AI_MATKEY_OPACITY);
      }

      // The face order is absolutely undefined for PLY, so we have to
      // use two-sided rendering to be sure it's ok.
      const int two_sided = 1;
      pcHelper->AddProperty(&two_sided, 1, AI_MATKEY_TWOSIDED);

      //default texture
      if (!defaultTexture.empty())
      {
        const aiString name(defaultTexture.c_str());
        pcHelper->AddProperty(&name, _AI_MATKEY_TEXTURE_BASE, aiTextureType_DIFFUSE, 0);
      }

      if (!pointsOnly)
      {
        const int two_sided = 1;
        pcHelper->AddProperty(&two_sided, 1, AI_MATKEY_TWOSIDED);
      }

      //set to wireframe, so when using this material info we can switch to points rendering
      if (pointsOnly)
      {
        const int wireframe = 1;
        pcHelper->AddProperty(&wireframe, 1, AI_MATKEY_ENABLE_WIREFRAME);
      }

      // add the newly created material instance to the list
      pvOut->push_back(pcHelper);
    }
  }
  else
  {
    // generate a default material
    aiMaterial* pcHelper = new aiMaterial();

    // fill in a default material
    int iMode = (int)aiShadingMode_Gouraud;
    pcHelper->AddProperty<int>(&iMode, 1, AI_MATKEY_SHADING_MODEL);

    //generate white material most 3D engine just multiply ambient / diffuse color with actual ambient / light color
    aiColor3D clr;
    clr.b = clr.g = clr.r = 1.0f;
    pcHelper->AddProperty<aiColor3D>(&clr, 1, AI_MATKEY_COLOR_DIFFUSE);
    pcHelper->AddProperty<aiColor3D>(&clr, 1, AI_MATKEY_COLOR_SPECULAR);

    clr.b = clr.g = clr.r = 1.0f;
    pcHelper->AddProperty<aiColor3D>(&clr, 1, AI_MATKEY_COLOR_AMBIENT);

    // The face order is absolutely undefined for PLY, so we have to
    // use two-sided rendering to be sure it's ok.
    if (!pointsOnly)
    {
      const int two_sided = 1;
      pcHelper->AddProperty(&two_sided, 1, AI_MATKEY_TWOSIDED);
    }

    //default texture
    if (!defaultTexture.empty())
    {
      const aiString name(defaultTexture.c_str());
      pcHelper->AddProperty(&name, _AI_MATKEY_TEXTURE_BASE, aiTextureType_DIFFUSE, 0);
    }

    //set to wireframe, so when using this material info we can switch to points rendering
    if (pointsOnly)
    {
      const int wireframe = 1;
      pcHelper->AddProperty(&wireframe, 1, AI_MATKEY_ENABLE_WIREFRAME);
    }

    pvOut->push_back(pcHelper);
  }
}

#endif // !! ASSIMP_BUILD_NO_PLY_IMPORTER