assimp.assimp/code/AssetLib/Ply/PlyParser.cpp

/*
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*/

/** @file Implementation of the PLY parser class */

#ifndef ASSIMP_BUILD_NO_PLY_IMPORTER

#include "PlyLoader.h"
#include <assimp/ByteSwapper.h>
#include <assimp/fast_atof.h>
#include <assimp/DefaultLogger.hpp>
#include <unordered_set>
#include <utility>

namespace Assimp {

std::string to_string(EElementSemantic e) {

    switch (e) {
    case EEST_Vertex:
        return std::string{ "vertex" };
    case EEST_TriStrip:
        return std::string{ "tristrips" };
    case EEST_Edge:
        return std::string{ "edge" };
    case EEST_Material:
        return std::string{ "material" };
    case EEST_TextureFile:
        return std::string{ "TextureFile" };
    default:
        return std::string{ "invalid" };
    }
}

// ------------------------------------------------------------------------------------------------
PLY::EDataType PLY::Property::ParseDataType(std::vector<char> &buffer) {
    ai_assert(!buffer.empty());

    PLY::EDataType eOut = PLY::EDT_INVALID;

    if (PLY::DOM::TokenMatch(buffer, "char", 4) ||
            PLY::DOM::TokenMatch(buffer, "int8", 4)) {
        eOut = PLY::EDT_Char;
    } else if (PLY::DOM::TokenMatch(buffer, "uchar", 5) ||
               PLY::DOM::TokenMatch(buffer, "uint8", 5)) {
        eOut = PLY::EDT_UChar;
    } else if (PLY::DOM::TokenMatch(buffer, "short", 5) ||
               PLY::DOM::TokenMatch(buffer, "int16", 5)) {
        eOut = PLY::EDT_Short;
    } else if (PLY::DOM::TokenMatch(buffer, "ushort", 6) ||
               PLY::DOM::TokenMatch(buffer, "uint16", 6)) {
        eOut = PLY::EDT_UShort;
    } else if (PLY::DOM::TokenMatch(buffer, "int32", 5) || PLY::DOM::TokenMatch(buffer, "int", 3)) {
        eOut = PLY::EDT_Int;
    } else if (PLY::DOM::TokenMatch(buffer, "uint32", 6) || PLY::DOM::TokenMatch(buffer, "uint", 4)) {
        eOut = PLY::EDT_UInt;
    } else if (PLY::DOM::TokenMatch(buffer, "float", 5) || PLY::DOM::TokenMatch(buffer, "float32", 7)) {
        eOut = PLY::EDT_Float;
    } else if (PLY::DOM::TokenMatch(buffer, "double64", 8) || PLY::DOM::TokenMatch(buffer, "double", 6) ||
               PLY::DOM::TokenMatch(buffer, "float64", 7)) {
        eOut = PLY::EDT_Double;
    }
    if (PLY::EDT_INVALID == eOut) {
        ASSIMP_LOG_INFO("Found unknown data type in PLY file. This is OK");
    }

    return eOut;
}

// ------------------------------------------------------------------------------------------------
PLY::ESemantic PLY::Property::ParseSemantic(std::vector<char> &buffer) {
    ai_assert(!buffer.empty());

    PLY::ESemantic eOut = PLY::EST_INVALID;
    if (PLY::DOM::TokenMatch(buffer, "red", 3)) {
        eOut = PLY::EST_Red;
    } else if (PLY::DOM::TokenMatch(buffer, "green", 5)) {
        eOut = PLY::EST_Green;
    } else if (PLY::DOM::TokenMatch(buffer, "blue", 4)) {
        eOut = PLY::EST_Blue;
    } else if (PLY::DOM::TokenMatch(buffer, "alpha", 5)) {
        eOut = PLY::EST_Alpha;
    } else if (PLY::DOM::TokenMatch(buffer, "vertex_index", 12) || PLY::DOM::TokenMatch(buffer, "vertex_indices", 14)) {
        eOut = PLY::EST_VertexIndex;
    } else if (PLY::DOM::TokenMatch(buffer, "texcoord", 8)) // Manage uv coords on faces
    {
        eOut = PLY::EST_TextureCoordinates;
    } else if (PLY::DOM::TokenMatch(buffer, "material_index", 14)) {
        eOut = PLY::EST_MaterialIndex;
    } else if (PLY::DOM::TokenMatch(buffer, "ambient_red", 11)) {
        eOut = PLY::EST_AmbientRed;
    } else if (PLY::DOM::TokenMatch(buffer, "ambient_green", 13)) {
        eOut = PLY::EST_AmbientGreen;
    } else if (PLY::DOM::TokenMatch(buffer, "ambient_blue", 12)) {
        eOut = PLY::EST_AmbientBlue;
    } else if (PLY::DOM::TokenMatch(buffer, "ambient_alpha", 13)) {
        eOut = PLY::EST_AmbientAlpha;
    } else if (PLY::DOM::TokenMatch(buffer, "diffuse_red", 11)) {
        eOut = PLY::EST_DiffuseRed;
    } else if (PLY::DOM::TokenMatch(buffer, "diffuse_green", 13)) {
        eOut = PLY::EST_DiffuseGreen;
    } else if (PLY::DOM::TokenMatch(buffer, "diffuse_blue", 12)) {
        eOut = PLY::EST_DiffuseBlue;
    } else if (PLY::DOM::TokenMatch(buffer, "diffuse_alpha", 13)) {
        eOut = PLY::EST_DiffuseAlpha;
    } else if (PLY::DOM::TokenMatch(buffer, "specular_red", 12)) {
        eOut = PLY::EST_SpecularRed;
    } else if (PLY::DOM::TokenMatch(buffer, "specular_green", 14)) {
        eOut = PLY::EST_SpecularGreen;
    } else if (PLY::DOM::TokenMatch(buffer, "specular_blue", 13)) {
        eOut = PLY::EST_SpecularBlue;
    } else if (PLY::DOM::TokenMatch(buffer, "specular_alpha", 14)) {
        eOut = PLY::EST_SpecularAlpha;
    } else if (PLY::DOM::TokenMatch(buffer, "opacity", 7)) {
        eOut = PLY::EST_Opacity;
    } else if (PLY::DOM::TokenMatch(buffer, "specular_power", 14)) {
        eOut = PLY::EST_PhongPower;
    } else if (PLY::DOM::TokenMatch(buffer, "r", 1)) {
        eOut = PLY::EST_Red;
    } else if (PLY::DOM::TokenMatch(buffer, "g", 1)) {
        eOut = PLY::EST_Green;
    } else if (PLY::DOM::TokenMatch(buffer, "b", 1)) {
        eOut = PLY::EST_Blue;
    }

    // NOTE: Blender3D exports texture coordinates as s,t tuples
    else if (PLY::DOM::TokenMatch(buffer, "u", 1) || PLY::DOM::TokenMatch(buffer, "s", 1) || PLY::DOM::TokenMatch(buffer, "tx", 2) || PLY::DOM::TokenMatch(buffer, "texture_u", 9)) {
        eOut = PLY::EST_UTextureCoord;
    } else if (PLY::DOM::TokenMatch(buffer, "v", 1) || PLY::DOM::TokenMatch(buffer, "t", 1) || PLY::DOM::TokenMatch(buffer, "ty", 2) || PLY::DOM::TokenMatch(buffer, "texture_v", 9)) {
        eOut = PLY::EST_VTextureCoord;
    } else if (PLY::DOM::TokenMatch(buffer, "x", 1)) {
        eOut = PLY::EST_XCoord;
    } else if (PLY::DOM::TokenMatch(buffer, "y", 1)) {
        eOut = PLY::EST_YCoord;
    } else if (PLY::DOM::TokenMatch(buffer, "z", 1)) {
        eOut = PLY::EST_ZCoord;
    } else if (PLY::DOM::TokenMatch(buffer, "nx", 2)) {
        eOut = PLY::EST_XNormal;
    } else if (PLY::DOM::TokenMatch(buffer, "ny", 2)) {
        eOut = PLY::EST_YNormal;
    } else if (PLY::DOM::TokenMatch(buffer, "nz", 2)) {
        eOut = PLY::EST_ZNormal;
    } else {
        ASSIMP_LOG_INFO("Found unknown property semantic in file. This is ok");
        PLY::DOM::SkipLine(buffer);
    }
    return eOut;
}

// ------------------------------------------------------------------------------------------------
bool PLY::Property::ParseProperty(std::vector<char> &buffer, PLY::Property *pOut) {
    ai_assert(!buffer.empty());

    // Forms supported:
    // "property float x"
    // "property list uchar int vertex_index"

    // skip leading spaces
    if (!PLY::DOM::SkipSpaces(buffer)) {
        return false;
    }

    // skip the "property" string at the beginning
    if (!PLY::DOM::TokenMatch(buffer, "property", 8)) {
        // seems not to be a valid property entry
        return false;
    }
    // get next word
    if (!PLY::DOM::SkipSpaces(buffer)) {
        return false;
    }
    if (PLY::DOM::TokenMatch(buffer, "list", 4)) {
        pOut->bIsList = true;

        // seems to be a list.
        if (EDT_INVALID == (pOut->eFirstType = PLY::Property::ParseDataType(buffer))) {
            // unable to parse list size data type
            PLY::DOM::SkipLine(buffer);
            return false;
        }
        if (!PLY::DOM::SkipSpaces(buffer)) return false;
        if (EDT_INVALID == (pOut->eType = PLY::Property::ParseDataType(buffer))) {
            // unable to parse list data type
            PLY::DOM::SkipLine(buffer);
            return false;
        }
    } else {
        if (EDT_INVALID == (pOut->eType = PLY::Property::ParseDataType(buffer))) {
            // unable to parse data type. Skip the property
            PLY::DOM::SkipLine(buffer);
            return false;
        }
    }

    if (!PLY::DOM::SkipSpaces(buffer))
        return false;

    pOut->Semantic = PLY::Property::ParseSemantic(buffer);

    if (PLY::EST_INVALID == pOut->Semantic) {
        ASSIMP_LOG_INFO("Found unknown semantic in PLY file. This is OK");
        std::string(&buffer[0], &buffer[0] + strlen(&buffer[0]));
    }

    PLY::DOM::SkipSpacesAndLineEnd(buffer);
    return true;
}

// ------------------------------------------------------------------------------------------------
PLY::EElementSemantic PLY::Element::ParseSemantic(std::vector<char> &buffer) {
    ai_assert(!buffer.empty());

    PLY::EElementSemantic eOut = PLY::EEST_INVALID;
    if (PLY::DOM::TokenMatch(buffer, "vertex", 6)) {
        eOut = PLY::EEST_Vertex;
    } else if (PLY::DOM::TokenMatch(buffer, "face", 4)) {
        eOut = PLY::EEST_Face;
    } else if (PLY::DOM::TokenMatch(buffer, "tristrips", 9)) {
        eOut = PLY::EEST_TriStrip;
    }
#if 0
  // TODO: maybe implement this?
  else if (PLY::DOM::TokenMatch(buffer,"range_grid",10))
  {
    eOut = PLY::EEST_Face;
  }
#endif
    else if (PLY::DOM::TokenMatch(buffer, "edge", 4)) {
        eOut = PLY::EEST_Edge;
    } else if (PLY::DOM::TokenMatch(buffer, "material", 8)) {
        eOut = PLY::EEST_Material;
    } else if (PLY::DOM::TokenMatch(buffer, "TextureFile", 11)) {
        eOut = PLY::EEST_TextureFile;
    }

    return eOut;
}

// ------------------------------------------------------------------------------------------------
bool PLY::Element::ParseElement(IOStreamBuffer<char> &streamBuffer, std::vector<char> &buffer, PLY::Element *pOut) {
    ai_assert(nullptr != pOut);
    // Example format: "element vertex 8"

    // skip leading spaces
    if (!PLY::DOM::SkipSpaces(buffer)) {
        return false;
    }

    // skip the "element" string at the beginning
    if (!PLY::DOM::TokenMatch(buffer, "element", 7) && !PLY::DOM::TokenMatch(buffer, "comment", 7)) {
        // seems not to be a valid property entry
        return false;
    }
    // get next word
    if (!PLY::DOM::SkipSpaces(buffer))
        return false;

    // parse the semantic of the element
    pOut->eSemantic = PLY::Element::ParseSemantic(buffer);
    if (PLY::EEST_INVALID == pOut->eSemantic) {
        // if the exact semantic can't be determined, just store
        // the original string identifier
        pOut->szName = std::string(&buffer[0], &buffer[0] + strlen(&buffer[0]));
        auto pos = pOut->szName.find_last_of(' ');
        if (pos != std::string::npos) {
            pOut->szName.erase(pos, pOut->szName.size());
        }
    }

    if (!PLY::DOM::SkipSpaces(buffer))
        return false;

    if (PLY::EEST_TextureFile == pOut->eSemantic) {
        char *endPos = &buffer[0] + (strlen(&buffer[0]) - 1);
        pOut->szName = std::string(&buffer[0], endPos);

        // go to the next line
        PLY::DOM::SkipSpacesAndLineEnd(buffer);

        return true;
    }

    // parse the number of occurrences of this element
    const char *pCur = (char *)&buffer[0];
    pOut->NumOccur = strtoul10(pCur, &pCur);

    // go to the next line
    PLY::DOM::SkipSpacesAndLineEnd(buffer);

    // now parse all properties of the element
    while (true) {
        streamBuffer.getNextLine(buffer);
        pCur = (char *)&buffer[0];

        // skip all comments and go to next line
        if (PLY::DOM::SkipComments(buffer)) continue;

        PLY::Property prop;
        if (!PLY::Property::ParseProperty(buffer, &prop))
            break;

        pOut->alProperties.push_back(prop);
    }

    return true;
}

bool PLY::DOM::SkipSpaces(std::vector<char> &buffer) {
    const char *pCur = buffer.empty() ? nullptr : (char *)&buffer[0];
    const char *end = pCur + buffer.size();
    bool ret = false;
    if (pCur) {
        const char *szCur = pCur;
        ret = Assimp::SkipSpaces(pCur, &pCur, end);

        uintptr_t iDiff = (uintptr_t)pCur - (uintptr_t)szCur;
        buffer.erase(buffer.begin(), buffer.begin() + iDiff);
        return ret;
    }

    return ret;
}

bool PLY::DOM::SkipLine(std::vector<char> &buffer) {
    const char *pCur = buffer.empty() ? nullptr : (char *)&buffer[0];
    const char *end = pCur + buffer.size();
    bool ret = false;
    if (pCur) {
        const char *szCur = pCur;
        ret = Assimp::SkipLine(pCur, &pCur, end);

        uintptr_t iDiff = (uintptr_t)pCur - (uintptr_t)szCur;
        buffer.erase(buffer.begin(), buffer.begin() + iDiff);
        return ret;
    }

    return ret;
}

bool PLY::DOM::TokenMatch(std::vector<char> &buffer, const char *token, unsigned int len) {
    const char *pCur = buffer.empty() ? nullptr : (char *)&buffer[0];
    bool ret = false;
    if (pCur) {
        const char *szCur = pCur;
        ret = Assimp::TokenMatch(pCur, token, len);

        uintptr_t iDiff = (uintptr_t)pCur - (uintptr_t)szCur;
        buffer.erase(buffer.begin(), buffer.begin() + iDiff);
        return ret;
    }

    return ret;
}

bool PLY::DOM::SkipSpacesAndLineEnd(std::vector<char> &buffer) {
    const char *pCur = buffer.empty() ? nullptr : (char *)&buffer[0];
    const char *end = pCur + buffer.size();
    bool ret = false;
    if (pCur) {
        const char *szCur = pCur;
        ret = Assimp::SkipSpacesAndLineEnd(pCur, &pCur, end);

        uintptr_t iDiff = (uintptr_t)pCur - (uintptr_t)szCur;
        buffer.erase(buffer.begin(), buffer.begin() + iDiff);
        return ret;
    }

    return ret;
}

bool PLY::DOM::SkipComments(std::vector<char> buffer) {
    ai_assert(!buffer.empty());

    std::vector<char> nbuffer = std::move(buffer);
    // skip spaces
    if (!SkipSpaces(nbuffer)) {
        return false;
    }

    if (TokenMatch(nbuffer, "comment", 7)) {
        if (!SkipSpaces(nbuffer))
            SkipLine(nbuffer);

        if (!TokenMatch(nbuffer, "TextureFile", 11)) {
            SkipLine(nbuffer);
            buffer = nbuffer;
            return true;
        }

        return true;
    }

    return false;
}

// ------------------------------------------------------------------------------------------------
bool PLY::DOM::ParseHeader(IOStreamBuffer<char> &streamBuffer, std::vector<char> &buffer, bool isBinary) {
    ASSIMP_LOG_VERBOSE_DEBUG("PLY::DOM::ParseHeader() begin");

    std::unordered_set<std::string> definedAlElements;
    // parse all elements
    while (!buffer.empty()) {
        // skip all comments
        PLY::DOM::SkipComments(buffer);

        PLY::Element out;
        if (PLY::Element::ParseElement(streamBuffer, buffer, &out)) {
            // add the element to the list of elements

            const auto propertyName = (out.szName.empty()) ? to_string(out.eSemantic) : out.szName;
            auto alreadyDefined = definedAlElements.find(propertyName);
            if (alreadyDefined != definedAlElements.end()) {
                throw DeadlyImportError("Property '" + propertyName + "' in header already defined ");
            }
            definedAlElements.insert(propertyName);
            alElements.push_back(out);
        } else if (TokenMatch(buffer, "end_header", 10)) {
            // we have reached the end of the header
            break;
        } else {
            // ignore unknown header elements
            if (!streamBuffer.getNextLine(buffer))
                return false;
        }
    }

    if (!isBinary) // it would occur an error, if binary data start with values as space or line end.
        SkipSpacesAndLineEnd(buffer);

    ASSIMP_LOG_VERBOSE_DEBUG("PLY::DOM::ParseHeader() succeeded");
    return true;
}

// ------------------------------------------------------------------------------------------------
bool PLY::DOM::ParseElementInstanceLists(IOStreamBuffer<char> &streamBuffer, std::vector<char> &buffer, PLYImporter *loader) {
    ASSIMP_LOG_VERBOSE_DEBUG("PLY::DOM::ParseElementInstanceLists() begin");
    alElementData.resize(alElements.size());

    std::vector<PLY::Element>::const_iterator i = alElements.begin();
    std::vector<PLY::ElementInstanceList>::iterator a = alElementData.begin();

    // parse all element instances
    // construct vertices and faces
    for (; i != alElements.end(); ++i, ++a) {
        if ((*i).eSemantic == EEST_Vertex || (*i).eSemantic == EEST_Face || (*i).eSemantic == EEST_TriStrip) {
            PLY::ElementInstanceList::ParseInstanceList(streamBuffer, buffer, &(*i), nullptr, loader);
        } else {
            (*a).alInstances.resize((*i).NumOccur);
            PLY::ElementInstanceList::ParseInstanceList(streamBuffer, buffer, &(*i), &(*a), nullptr);
        }
    }

    ASSIMP_LOG_VERBOSE_DEBUG("PLY::DOM::ParseElementInstanceLists() succeeded");
    return true;
}

// ------------------------------------------------------------------------------------------------
bool PLY::DOM::ParseElementInstanceListsBinary(IOStreamBuffer<char> &streamBuffer, std::vector<char> &buffer,
        const char *&pCur,
        unsigned int &bufferSize,
        PLYImporter *loader,
        bool p_bBE) {
    ASSIMP_LOG_VERBOSE_DEBUG("PLY::DOM::ParseElementInstanceListsBinary() begin");
    alElementData.resize(alElements.size());

    std::vector<PLY::Element>::const_iterator i = alElements.begin();
    std::vector<PLY::ElementInstanceList>::iterator a = alElementData.begin();

    // parse all element instances
    for (; i != alElements.end(); ++i, ++a) {
        if ((*i).eSemantic == EEST_Vertex || (*i).eSemantic == EEST_Face || (*i).eSemantic == EEST_TriStrip) {
            PLY::ElementInstanceList::ParseInstanceListBinary(streamBuffer, buffer, pCur, bufferSize, &(*i), nullptr, loader, p_bBE);
        } else {
            (*a).alInstances.resize((*i).NumOccur);
            PLY::ElementInstanceList::ParseInstanceListBinary(streamBuffer, buffer, pCur, bufferSize, &(*i), &(*a), nullptr, p_bBE);
        }
    }

    ASSIMP_LOG_VERBOSE_DEBUG("PLY::DOM::ParseElementInstanceListsBinary() succeeded");
    return true;
}

// ------------------------------------------------------------------------------------------------
bool PLY::DOM::ParseInstanceBinary(IOStreamBuffer<char> &streamBuffer, DOM *p_pcOut, PLYImporter *loader, bool p_bBE) {
    ai_assert(nullptr != p_pcOut);
    ai_assert(nullptr != loader);

    std::vector<char> buffer;
    streamBuffer.getNextLine(buffer);

    ASSIMP_LOG_VERBOSE_DEBUG("PLY::DOM::ParseInstanceBinary() begin");

    if (!p_pcOut->ParseHeader(streamBuffer, buffer, true)) {
        ASSIMP_LOG_VERBOSE_DEBUG("PLY::DOM::ParseInstanceBinary() failure");
        return false;
    }

    streamBuffer.getNextBlock(buffer);

    unsigned int bufferSize = static_cast<unsigned int>(buffer.size());
    const char *pCur = (char *)&buffer[0];
    if (!p_pcOut->ParseElementInstanceListsBinary(streamBuffer, buffer, pCur, bufferSize, loader, p_bBE)) {
        ASSIMP_LOG_VERBOSE_DEBUG("PLY::DOM::ParseInstanceBinary() failure");
        return false;
    }
    ASSIMP_LOG_VERBOSE_DEBUG("PLY::DOM::ParseInstanceBinary() succeeded");
    return true;
}

// ------------------------------------------------------------------------------------------------
bool PLY::DOM::ParseInstance(IOStreamBuffer<char> &streamBuffer, DOM *p_pcOut, PLYImporter *loader) {
    ai_assert(nullptr != p_pcOut);
    ai_assert(nullptr != loader);

    std::vector<char> buffer;
    streamBuffer.getNextLine(buffer);

    ASSIMP_LOG_VERBOSE_DEBUG("PLY::DOM::ParseInstance() begin");

    if (!p_pcOut->ParseHeader(streamBuffer, buffer, false)) {
        ASSIMP_LOG_VERBOSE_DEBUG("PLY::DOM::ParseInstance() failure");
        return false;
    }

    // get next line after header
    streamBuffer.getNextLine(buffer);
    if (!p_pcOut->ParseElementInstanceLists(streamBuffer, buffer, loader)) {
        ASSIMP_LOG_VERBOSE_DEBUG("PLY::DOM::ParseInstance() failure");
        return false;
    }
    ASSIMP_LOG_VERBOSE_DEBUG("PLY::DOM::ParseInstance() succeeded");
    return true;
}

// ------------------------------------------------------------------------------------------------
bool PLY::ElementInstanceList::ParseInstanceList(
        IOStreamBuffer<char> &streamBuffer,
        std::vector<char> &buffer,
        const PLY::Element *pcElement,
        PLY::ElementInstanceList *p_pcOut,
        PLYImporter *loader) {
    ai_assert(nullptr != pcElement);

    // parse all elements
    if (EEST_INVALID == pcElement->eSemantic || pcElement->alProperties.empty()) {
        // if the element has an unknown semantic we can skip all lines
        // However, there could be comments
        for (unsigned int i = 0; i < pcElement->NumOccur; ++i) {
            PLY::DOM::SkipComments(buffer);
            PLY::DOM::SkipLine(buffer);
            streamBuffer.getNextLine(buffer);
        }
    } else {
        const char *pCur = (const char *)&buffer[0];
        const char *end = pCur + buffer.size();
        // be sure to have enough storage
        for (unsigned int i = 0; i < pcElement->NumOccur; ++i) {
            if (p_pcOut)
                PLY::ElementInstance::ParseInstance(pCur, end, pcElement, &p_pcOut->alInstances[i]);
            else {
                ElementInstance elt;
                PLY::ElementInstance::ParseInstance(pCur, end, pcElement, &elt);

                // Create vertex or face
                if (pcElement->eSemantic == EEST_Vertex) {
                    // call loader instance from here
                    loader->LoadVertex(pcElement, &elt, i);
                } else if (pcElement->eSemantic == EEST_Face) {
                    // call loader instance from here
                    loader->LoadFace(pcElement, &elt, i);
                } else if (pcElement->eSemantic == EEST_TriStrip) {
                    // call loader instance from here
                    loader->LoadFace(pcElement, &elt, i);
                }
            }

            streamBuffer.getNextLine(buffer);
            pCur = (buffer.empty()) ? nullptr : (const char *)&buffer[0];
        }
    }
    return true;
}

// ------------------------------------------------------------------------------------------------
bool PLY::ElementInstanceList::ParseInstanceListBinary(
        IOStreamBuffer<char> &streamBuffer,
        std::vector<char> &buffer,
        const char *&pCur,
        unsigned int &bufferSize,
        const PLY::Element *pcElement,
        PLY::ElementInstanceList *p_pcOut,
        PLYImporter *loader,
        bool p_bBE /* = false */) {
    ai_assert(nullptr != pcElement);

    // we can add special handling code for unknown element semantics since
    // we can't skip it as a whole block (we don't know its exact size
    // due to the fact that lists could be contained in the property list
    // of the unknown element)
    for (unsigned int i = 0; i < pcElement->NumOccur; ++i) {
        if (p_pcOut)
            PLY::ElementInstance::ParseInstanceBinary(streamBuffer, buffer, pCur, bufferSize, pcElement, &p_pcOut->alInstances[i], p_bBE);
        else {
            ElementInstance elt;
            PLY::ElementInstance::ParseInstanceBinary(streamBuffer, buffer, pCur, bufferSize, pcElement, &elt, p_bBE);

            // Create vertex or face
            if (pcElement->eSemantic == EEST_Vertex) {
                // call loader instance from here
                loader->LoadVertex(pcElement, &elt, i);
            } else if (pcElement->eSemantic == EEST_Face) {
                // call loader instance from here
                loader->LoadFace(pcElement, &elt, i);
            } else if (pcElement->eSemantic == EEST_TriStrip) {
                // call loader instance from here
                loader->LoadFace(pcElement, &elt, i);
            }
        }
    }
    return true;
}

// ------------------------------------------------------------------------------------------------
bool PLY::ElementInstance::ParseInstance(const char *&pCur, const char *end,
        const PLY::Element *pcElement,
        PLY::ElementInstance *p_pcOut) {
    ai_assert(nullptr != pcElement);
    ai_assert(nullptr != p_pcOut);

    // allocate enough storage
    p_pcOut->alProperties.resize(pcElement->alProperties.size());

    std::vector<PLY::PropertyInstance>::iterator i = p_pcOut->alProperties.begin();
    std::vector<PLY::Property>::const_iterator a = pcElement->alProperties.begin();
    for (; i != p_pcOut->alProperties.end(); ++i, ++a) {
        if (!(PLY::PropertyInstance::ParseInstance(pCur, end, &(*a), &(*i)))) {
            ASSIMP_LOG_WARN("Unable to parse property instance. "
                            "Skipping this element instance");

            PLY::PropertyInstance::ValueUnion v = PLY::PropertyInstance::DefaultValue((*a).eType);
            (*i).avList.push_back(v);
        }
    }
    return true;
}

// ------------------------------------------------------------------------------------------------
bool PLY::ElementInstance::ParseInstanceBinary(
        IOStreamBuffer<char> &streamBuffer,
        std::vector<char> &buffer,
        const char *&pCur,
        unsigned int &bufferSize,
        const PLY::Element *pcElement,
        PLY::ElementInstance *p_pcOut,
        bool p_bBE /* = false */) {
    ai_assert(nullptr != pcElement);
    ai_assert(nullptr != p_pcOut);

    // allocate enough storage
    p_pcOut->alProperties.resize(pcElement->alProperties.size());

    std::vector<PLY::PropertyInstance>::iterator i = p_pcOut->alProperties.begin();
    std::vector<PLY::Property>::const_iterator a = pcElement->alProperties.begin();
    for (; i != p_pcOut->alProperties.end(); ++i, ++a) {
        if (!(PLY::PropertyInstance::ParseInstanceBinary(streamBuffer, buffer, pCur, bufferSize, &(*a), &(*i), p_bBE))) {
            ASSIMP_LOG_WARN("Unable to parse binary property instance. "
                            "Skipping this element instance");

            (*i).avList.push_back(PLY::PropertyInstance::DefaultValue((*a).eType));
        }
    }
    return true;
}

// ------------------------------------------------------------------------------------------------
bool PLY::PropertyInstance::ParseInstance(const char *&pCur, const char *end, const PLY::Property *prop,
        PLY::PropertyInstance *p_pcOut) {
    ai_assert(nullptr != prop);
    ai_assert(nullptr != p_pcOut);

    // skip spaces at the beginning
    if (!SkipSpaces(&pCur, end)) {
        return false;
    }

    if (prop->bIsList) {
        // parse the number of elements in the list
        PLY::PropertyInstance::ValueUnion v;
        PLY::PropertyInstance::ParseValue(pCur, prop->eFirstType, &v);

        // convert to unsigned int
        unsigned int iNum = PLY::PropertyInstance::ConvertTo<unsigned int>(v, prop->eFirstType);

        // parse all list elements
        p_pcOut->avList.resize(iNum);
        for (unsigned int i = 0; i < iNum; ++i) {
            if (!SkipSpaces(&pCur, end))
                return false;

            PLY::PropertyInstance::ParseValue(pCur, prop->eType, &p_pcOut->avList[i]);
        }
    } else {
        // parse the property
        PLY::PropertyInstance::ValueUnion v;

        PLY::PropertyInstance::ParseValue(pCur, prop->eType, &v);
        p_pcOut->avList.push_back(v);
    }
    SkipSpacesAndLineEnd(&pCur, end);
    return true;
}

// ------------------------------------------------------------------------------------------------
bool PLY::PropertyInstance::ParseInstanceBinary(IOStreamBuffer<char> &streamBuffer, std::vector<char> &buffer,
        const char *&pCur,
        unsigned int &bufferSize,
        const PLY::Property *prop,
        PLY::PropertyInstance *p_pcOut,
        bool p_bBE) {
    ai_assert(nullptr != prop);
    ai_assert(nullptr != p_pcOut);

    // parse all elements
    if (prop->bIsList) {
        // parse the number of elements in the list
        PLY::PropertyInstance::ValueUnion v;
        PLY::PropertyInstance::ParseValueBinary(streamBuffer, buffer, pCur, bufferSize, prop->eFirstType, &v, p_bBE);

        // convert to unsigned int
        unsigned int iNum = PLY::PropertyInstance::ConvertTo<unsigned int>(v, prop->eFirstType);

        // parse all list elements
        p_pcOut->avList.resize(iNum);
        for (unsigned int i = 0; i < iNum; ++i) {
            PLY::PropertyInstance::ParseValueBinary(streamBuffer, buffer, pCur, bufferSize, prop->eType, &p_pcOut->avList[i], p_bBE);
        }
    } else {
        // parse the property
        PLY::PropertyInstance::ValueUnion v;
        PLY::PropertyInstance::ParseValueBinary(streamBuffer, buffer, pCur, bufferSize, prop->eType, &v, p_bBE);
        p_pcOut->avList.push_back(v);
    }
    return true;
}

// ------------------------------------------------------------------------------------------------
PLY::PropertyInstance::ValueUnion PLY::PropertyInstance::DefaultValue(PLY::EDataType eType) {
    PLY::PropertyInstance::ValueUnion out;

    switch (eType) {
    case EDT_Float:
        out.fFloat = 0.f;
        return out;

    case EDT_Double:
        out.fDouble = 0.;
        return out;

    default:;
    };
    out.iUInt = 0;
    return out;
}

// ------------------------------------------------------------------------------------------------
bool PLY::PropertyInstance::ParseValue(const char *&pCur,
        PLY::EDataType eType,
        PLY::PropertyInstance::ValueUnion *out) {
    ai_assert(nullptr != pCur);
    ai_assert(nullptr != out);

    // calc element size
    bool ret = true;
    switch (eType) {
    case EDT_UInt:
    case EDT_UShort:
    case EDT_UChar:

        out->iUInt = (uint32_t)strtoul10(pCur, &pCur);
        break;

    case EDT_Int:
    case EDT_Short:
    case EDT_Char:

        out->iInt = (int32_t)strtol10(pCur, &pCur);
        break;

    case EDT_Float:
        // technically this should cast to float, but people tend to use float descriptors for double data
        // this is the best way to not risk losing precision on import and it doesn't hurt to do this
        ai_real f;
        pCur = fast_atoreal_move<ai_real>(pCur, f);
        out->fFloat = (ai_real)f;
        break;

    case EDT_Double:
        double d;
        pCur = fast_atoreal_move<double>(pCur, d);
        out->fDouble = (double)d;
        break;

    case EDT_INVALID:
    default:
        ret = false;
        break;
    }

    return ret;
}

// ------------------------------------------------------------------------------------------------
bool PLY::PropertyInstance::ParseValueBinary(IOStreamBuffer<char> &streamBuffer,
        std::vector<char> &buffer,
        const char *&pCur,
        unsigned int &bufferSize,
        PLY::EDataType eType,
        PLY::PropertyInstance::ValueUnion *out,
        bool p_bBE) {
    ai_assert(nullptr != out);

    // calc element size
    unsigned int lsize = 0;
    switch (eType) {
    case EDT_Char:
    case EDT_UChar:
        lsize = 1;
        break;

    case EDT_UShort:
    case EDT_Short:
        lsize = 2;
        break;

    case EDT_UInt:
    case EDT_Int:
    case EDT_Float:
        lsize = 4;
        break;

    case EDT_Double:
        lsize = 8;
        break;

    case EDT_INVALID:
    default:
        break;
    }

    // read the next file block if needed
    if (bufferSize < lsize) {
        std::vector<char> nbuffer;
        if (streamBuffer.getNextBlock(nbuffer)) {
            // concat buffer contents
            buffer = std::vector<char>(buffer.end() - bufferSize, buffer.end());
            buffer.insert(buffer.end(), nbuffer.begin(), nbuffer.end());
            nbuffer.clear();
            bufferSize = static_cast<unsigned int>(buffer.size());
            pCur = (char *)&buffer[0];
        } else {
            throw DeadlyImportError("Invalid .ply file: File corrupted");
        }
    }

    bool ret = true;
    switch (eType) {
    case EDT_UInt: {
        uint32_t t;
        memcpy(&t, pCur, sizeof(uint32_t));
        pCur += sizeof(uint32_t);

        // Swap endianness
        if (p_bBE) ByteSwap::Swap(&t);
        out->iUInt = t;
        break;
    }

    case EDT_UShort: {
        uint16_t t;
        memcpy(&t, pCur, sizeof(uint16_t));
        pCur += sizeof(uint16_t);

        // Swap endianness
        if (p_bBE) ByteSwap::Swap(&t);
        out->iUInt = t;
        break;
    }

    case EDT_UChar: {
        uint8_t t;
        memcpy(&t, pCur, sizeof(uint8_t));
        pCur += sizeof(uint8_t);
        out->iUInt = t;
        break;
    }

    case EDT_Int: {
        int32_t t;
        memcpy(&t, pCur, sizeof(int32_t));
        pCur += sizeof(int32_t);

        // Swap endianness
        if (p_bBE) ByteSwap::Swap(&t);
        out->iInt = t;
        break;
    }

    case EDT_Short: {
        int16_t t;
        memcpy(&t, pCur, sizeof(int16_t));
        pCur += sizeof(int16_t);

        // Swap endianness
        if (p_bBE) ByteSwap::Swap(&t);
        out->iInt = t;
        break;
    }

    case EDT_Char: {
        int8_t t;
        memcpy(&t, pCur, sizeof(int8_t));
        pCur += sizeof(int8_t);
        out->iInt = t;
        break;
    }

    case EDT_Float: {
        float t;
        memcpy(&t, pCur, sizeof(float));
        pCur += sizeof(float);

        // Swap endianness
        if (p_bBE) ByteSwap::Swap(&t);
        out->fFloat = t;
        break;
    }
    case EDT_Double: {
        double t;
        memcpy(&t, pCur, sizeof(double));
        pCur += sizeof(double);

        // Swap endianness
        if (p_bBE) ByteSwap::Swap(&t);
        out->fDouble = t;
        break;
    }
    default:
        ret = false;
    }

    bufferSize -= lsize;

    return ret;
}

} // namespace Assimp

#endif // !! ASSIMP_BUILD_NO_PLY_IMPORTER