assimp/tools/assimp_cmd/CompareDump.cpp

/*
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*/

/** @file  CompareDump.cpp
 *  @brief Implementation of the 'assimp cmpdmp', which compares
 *    two model dumps for equality. It plays an important role
 *    in the regression test suite.
 */

#include "Main.h"
const char* AICMD_MSG_CMPDUMP_HELP =
"assimp cmpdump <actual> <expected>\n"
"\tCompare two short dumps produced with \'assimp dump <..> -s\' for equality.\n"
;

#include "Common/assbin_chunks.h"

////////////////////////////////////////////////////////////////////////////////////////////////////
#include "generic_inserter.hpp"
#include <map>
#include <deque>
#include <stack>
#include <sstream>
#include <iostream>
#include <assimp/ai_assert.h>

// get << for aiString
template <typename char_t, typename traits_t>
void mysprint(std::basic_ostream<char_t, traits_t>& os,  const aiString& vec)   {
    os << "[length: \'" << std::dec << vec.length << "\' content: \'"  << vec.data << "\']";
}

template <typename char_t, typename traits_t>
std::basic_ostream<char_t, traits_t>& operator<< (std::basic_ostream<char_t, traits_t>& os, const aiString& vec)    {
    return generic_inserter(mysprint<char_t,traits_t>, os, vec);
}

class sliced_chunk_iterator;
////////////////////////////////////////////////////////////////////////////////////////////////////
/// @class  compare_fails_exception
///
/// @brief  Sentinel exception to return quickly from deeply nested control paths
////////////////////////////////////////////////////////////////////////////////////////////////////
class compare_fails_exception : public virtual std::exception {
public:

    enum {MAX_ERR_LEN = 4096};

    /* public c'tors */
    compare_fails_exception(const char* msg) {
        strncpy(mywhat,msg,MAX_ERR_LEN-1);
        strcat(mywhat,"\n");
    }

    /* public member functions */
    const char* what() const throw() {
        return mywhat;
    }

private:

    char mywhat[MAX_ERR_LEN+1];
};


#define MY_FLT_EPSILON 1e-1f
#define MY_DBL_EPSILON 1e-1
////////////////////////////////////////////////////////////////////////////////////////////////////
/// @class  comparer_context
///
/// @brief  Record our way through the files to be compared and dump useful information if we fail.
////////////////////////////////////////////////////////////////////////////////////////////////////
class comparer_context {
    friend class sliced_chunk_iterator;

public:

    /* construct given two file handles to compare */
    comparer_context(FILE* actual,FILE* expect)
        : actual(actual)
        , expect(expect)
        , cnt_chunks(0)
    {
        ai_assert(actual);
        ai_assert(expect);

        fseek(actual,0,SEEK_END);
        lengths.emplace(static_cast<uint32_t>(ftell(actual)),0);
        fseek(actual,0,SEEK_SET);

        history.emplace_back("---",PerChunkCounter());
    }

public:


    /* set new scope */
    void push_elem(const char* msg) {
        const std::string s = msg;

        PerChunkCounter::const_iterator it = history.back().second.find(s);
        if(it != history.back().second.end()) {
            ++history.back().second[s];
        }
        else history.back().second[s] = 0;

        history.emplace_back(s,PerChunkCounter());
        debug_trace.push_back("PUSH " + s);
    }

    /* leave current scope */
    void pop_elem() {
        ai_assert(history.size());
        debug_trace.push_back("POP "+ history.back().first);
        history.pop_back();
    }


    /* push current chunk length and start offset on top of stack */
    void push_length(uint32_t nl, uint32_t start) {
        lengths.emplace(nl,start);
        ++cnt_chunks;
    }

    /* pop the chunk length stack */
    void pop_length() {
        ai_assert(lengths.size());
        lengths.pop();
    }

    /* access the current chunk length */
    uint32_t get_latest_chunk_length() {
        ai_assert(lengths.size());
        return lengths.top().first;
    }

    /* access the current chunk start offset */
    uint32_t get_latest_chunk_start() {
        ai_assert(lengths.size());
        return lengths.top().second;
    }

    /* total number of chunk headers passed so far*/
    uint32_t get_num_chunks() {
        return cnt_chunks;
    }


    /* get ACTUAL file desc. != NULL */
    FILE* get_actual() const {
        return actual;
    }

    /* get EXPECT file desc. != NULL */
    FILE* get_expect() const {
        return expect;
    }


    /* compare next T from both streams, name occurs in error messages */
    template<typename T> T cmp(const std::string& name) {
        T a,e;
        read(a,e);

        if(a != e) {
            std::stringstream ss;
            failure((ss<< "Expected " << e << ", but actual is " << a,
                ss.str()),name);
        }
    //  std::cout << name << " " << std::hex << a << std::endl;
        return a;
    }

    /* compare next num T's from both streams, name occurs in error messages */
    template<typename T> void cmp(size_t num,const std::string& name) {
        for(size_t n = 0; n < num; ++n) {
            std::stringstream ss;
            cmp<T>((ss<<name<<"["<<n<<"]",ss.str()));
    //      std::cout << name << " " << std::hex << a << std::endl;
        }
    }

    /* Bounds of an aiVector3D array (separate function
     *  because partial specializations of member functions are illegal--)*/
    template<typename T> void cmp_bounds(const std::string& name) {
        cmp<T> (name+".<minimum-value>");
        cmp<T> (name+".<maximum-value>");
    }

private:

    /* Report failure */
    AI_WONT_RETURN void failure(const std::string& err, const std::string& name) AI_WONT_RETURN_SUFFIX {
        std::stringstream ss;
        throw compare_fails_exception((ss
            << "Files are different at "
            << history.back().first
            << "."
            << name
            << ".\nError is: "
            << err
            << ".\nCurrent position in scene hierarchy is "
            << print_hierarchy(),ss.str().c_str()
            ));
    }

    /** print our 'stack' */
    std::string print_hierarchy() {
        std::stringstream ss;
        ss << "\n";

        const char* last = history.back().first.c_str();
        std::string pad;

        for(ChunkHistory::reverse_iterator rev = history.rbegin(),
            end = history.rend(); rev != end; ++rev, pad += "  ")
        {
            ss << pad << (*rev).first << "(Index: " << (*rev).second[last] << ")" << "\n";
            last = (*rev).first.c_str();
        }

        ss << std::endl << "Debug trace: "<< "\n";
        for (std::vector<std::string>::const_iterator it = debug_trace.begin(); it != debug_trace.end(); ++it) {
            ss << *it << "\n";
        }
        ss << std::flush;

        return ss.str();
    }


    /* read from both streams at the same time */
    template <typename T> void read(T& filla,T& fille) {
        if(1 != fread(&filla,sizeof(T),1,actual)) {
            EOFActual();
        }
        if(1 != fread(&fille,sizeof(T),1,expect)) {
            EOFExpect();
        }
    }

private:

    void EOFActual() {
        std::stringstream ss;
        throw compare_fails_exception((ss
            << "Unexpected EOF reading ACTUAL.\nCurrent position in scene hierarchy is "
            << print_hierarchy(),ss.str().c_str()
            ));
    }

    void EOFExpect() {
        std::stringstream ss;
        throw compare_fails_exception((ss
            << "Unexpected EOF reading EXPECT.\nCurrent position in scene hierarchy is "
            << print_hierarchy(),ss.str().c_str()
            ));
    }


    FILE *const actual, *const expect;

    typedef std::map<std::string,unsigned int> PerChunkCounter;
    typedef std::pair<std::string,PerChunkCounter> HistoryEntry;

    typedef std::deque<HistoryEntry> ChunkHistory;
    ChunkHistory history;

    std::vector<std::string> debug_trace;

    typedef std::stack<std::pair<uint32_t,uint32_t> > LengthStack;
    LengthStack lengths;

    uint32_t cnt_chunks;
};


////////////////////////////////////////////////////////////////////////////////////////////////////
/* specialization for aiString (it needs separate handling because its on-disk representation
 * differs from its binary representation in memory and can't be treated as an array of n T's.*/
template <> void comparer_context :: read<aiString>(aiString& filla,aiString& fille) {
    uint32_t lena,lene;
    read(lena,lene);

    if(lena && 1 != fread(&filla.data,lena,1,actual)) {
        EOFActual();
    }
    if(lene && 1 != fread(&fille.data,lene,1,expect)) {
        EOFExpect();
    }

    fille.data[fille.length=static_cast<unsigned int>(lene)] = '\0';
    filla.data[filla.length=static_cast<unsigned int>(lena)] = '\0';
}

////////////////////////////////////////////////////////////////////////////////////////////////////
/* Specialization for float, uses epsilon for comparisons*/
template<> float comparer_context :: cmp<float>(const std::string& name)
{
    float a,e,t;
    read(a,e);

    if((t=fabs(a-e)) > MY_FLT_EPSILON) {
        std::stringstream ss;
        failure((ss<< "Expected " << e << ", but actual is "
            << a << " (delta is " << t << ")", ss.str()),name);
    }
    return a;
}

////////////////////////////////////////////////////////////////////////////////////////////////////
/* Specialization for double, uses epsilon for comparisons*/
template<> double comparer_context :: cmp<double>(const std::string& name)
{
    double a,e,t;
    read(a,e);

    if((t=fabs(a-e)) > MY_DBL_EPSILON) {
        std::stringstream ss;
        failure((ss<< "Expected " << e << ", but actual is "
            << a << " (delta is " << t << ")", ss.str()),name);
    }
    return a;
}

////////////////////////////////////////////////////////////////////////////////////////////////////
/* Specialization for aiVector3D */
template<> aiVector3D comparer_context :: cmp<aiVector3D >(const std::string& name)
{
    const float x = cmp<float>(name+".x");
    const float y = cmp<float>(name+".y");
    const float z = cmp<float>(name+".z");

    return aiVector3D(x,y,z);
}

////////////////////////////////////////////////////////////////////////////////////////////////////
/* Specialization for aiColor4D */
template<> aiColor4D comparer_context :: cmp<aiColor4D >(const std::string& name)
{
    const float r = cmp<float>(name+".r");
    const float g = cmp<float>(name+".g");
    const float b = cmp<float>(name+".b");
    const float a = cmp<float>(name+".a");

    return aiColor4D(r,g,b,a);
}

////////////////////////////////////////////////////////////////////////////////////////////////////
/* Specialization for aiQuaternion */
template<> aiQuaternion comparer_context :: cmp<aiQuaternion >(const std::string& name)
{
    const float w = cmp<float>(name+".w");
    const float x = cmp<float>(name+".x");
    const float y = cmp<float>(name+".y");
    const float z = cmp<float>(name+".z");

    return aiQuaternion(w,x,y,z);
}

////////////////////////////////////////////////////////////////////////////////////////////////////
/* Specialization for aiQuatKey */
template<> aiQuatKey comparer_context :: cmp<aiQuatKey >(const std::string& name)
{
    const double mTime = cmp<double>(name+".mTime");
    const aiQuaternion mValue = cmp<aiQuaternion>(name+".mValue");

    return aiQuatKey(mTime,mValue);
}

////////////////////////////////////////////////////////////////////////////////////////////////////
/* Specialization for aiVectorKey */
template<> aiVectorKey comparer_context :: cmp<aiVectorKey >(const std::string& name)
{
    const double mTime = cmp<double>(name+".mTime");
    const aiVector3D mValue = cmp<aiVector3D>(name+".mValue");

    return aiVectorKey(mTime,mValue);
}

////////////////////////////////////////////////////////////////////////////////////////////////////
/* Specialization for aiMatrix4x4 */
template<> aiMatrix4x4 comparer_context :: cmp<aiMatrix4x4 >(const std::string& name)
{
    aiMatrix4x4 res;
    for(unsigned int i = 0; i < 4; ++i) {
        for(unsigned int j = 0; j < 4; ++j) {
            std::stringstream ss;
            res[i][j] = cmp<float>(name+(ss<<".m"<<i<<j,ss.str()));
        }
    }

    return res;
}

////////////////////////////////////////////////////////////////////////////////////////////////////
/* Specialization for aiVertexWeight */
template<> aiVertexWeight comparer_context :: cmp<aiVertexWeight >(const std::string& name)
{
    const unsigned int mVertexId = cmp<unsigned int>(name+".mVertexId");
    const float mWeight = cmp<float>(name+".mWeight");

    return aiVertexWeight(mVertexId,mWeight);
}

////////////////////////////////////////////////////////////////////////////////////////////////////
/// @class  sliced_chunk_iterator
///
/// @brief  Helper to iterate easily through corresponding chunks of two dumps simultaneously.
///
/// Not a *real* iterator, doesn't fully conform to the isocpp iterator spec
////////////////////////////////////////////////////////////////////////////////////////////////////
class sliced_chunk_iterator {

    friend class sliced_chunk_reader;
    sliced_chunk_iterator(comparer_context& ctx, long end)
        : ctx(ctx)
        , endit(false)
        , next(std::numeric_limits<long>::max())
        , end(end)
    {
        load_next();
    }

public:

    ~sliced_chunk_iterator() {
        fseek(ctx.get_actual(),end,SEEK_SET);
        fseek(ctx.get_expect(),end,SEEK_SET);
    }

public:

    /* get current chunk head */
    typedef std::pair<uint32_t,uint32_t> Chunk;
    const Chunk& operator*() {
        return current;
    }

    /* get to next chunk head */
    const sliced_chunk_iterator& operator++() {
        cleanup();
        load_next();
        return *this;
    }

    /* */
    bool is_end() const {
        return endit;
    }

private:

    /* get to the end of *this* chunk */
    void cleanup() {
        if(next != std::numeric_limits<long>::max()) {
            fseek(ctx.get_actual(),next,SEEK_SET);
            fseek(ctx.get_expect(),next,SEEK_SET);

            ctx.pop_length();
        }
    }

    /* advance to the next chunk */
    void load_next() {

        Chunk actual;
        size_t res=0;

        const long cur = ftell(ctx.get_expect());
        if(end-cur<8) {
            current = std::make_pair(0u,0u);
            endit = true;
            return;
        }

        res|=fread(&current.first,4,1,ctx.get_expect());
        res|=fread(&current.second,4,1,ctx.get_expect())    <<1u;
        res|=fread(&actual.first,4,1,ctx.get_actual())      <<2u;
        res|=fread(&actual.second,4,1,ctx.get_actual())     <<3u;

        if(res!=0xf) {
            ctx.failure("IO Error reading chunk head, dumps are malformed","<ChunkHead>");
        }

        if (current.first != actual.first) {
            std::stringstream ss;
            ctx.failure((ss
                <<"Chunk headers do not match. EXPECT: "
                << std::hex << current.first
                <<" ACTUAL: "
                << /*std::hex */actual.first,
                ss.str()),
                "<ChunkHead>");
        }

        if (current.first != actual.first) {
            std::stringstream ss;
            ctx.failure((ss
                <<"Chunk lengths do not match. EXPECT: "
                <<current.second
                <<" ACTUAL: "
                << actual.second,
                ss.str()),
                "<ChunkHead>");
        }

        next = cur+current.second+8;
        ctx.push_length(current.second,cur+8);
    }

    comparer_context& ctx;
    Chunk current;
    bool endit;
    long next,end;
};

////////////////////////////////////////////////////////////////////////////////////////////////////
/// @class  sliced_chunk_reader
///
/// @brief  Helper to iterate easily through corresponding chunks of two dumps simultaneously.
////////////////////////////////////////////////////////////////////////////////////////////////////
class sliced_chunk_reader  {
public:

    //
    sliced_chunk_reader(comparer_context& ctx)
        : ctx(ctx)
    {}

    //
    ~sliced_chunk_reader() = default;

public:

    sliced_chunk_iterator begin() const {
        return sliced_chunk_iterator(ctx,ctx.get_latest_chunk_length()+
            ctx.get_latest_chunk_start());
    }

private:

    comparer_context& ctx;
};

////////////////////////////////////////////////////////////////////////////////////////////////////
/// @class  scoped_chunk
///
/// @brief  Utility to simplify usage of comparer_context.push_elem/pop_elem
////////////////////////////////////////////////////////////////////////////////////////////////////
class scoped_chunk {
public:

    //
    scoped_chunk(comparer_context& ctx,const char* msg)
        : ctx(ctx)
    {
        ctx.push_elem(msg);
    }

    //
    ~scoped_chunk()
    {
        ctx.pop_elem();
    }

private:

    comparer_context& ctx;
};

////////////////////////////////////////////////////////////////////////////////////////////////////
void CompareOnTheFlyMaterialProperty(comparer_context& comp)    {
    scoped_chunk chunk(comp,"aiMaterialProperty");

    comp.cmp<aiString>("mKey");
    comp.cmp<uint32_t>("mSemantic");
    comp.cmp<uint32_t>("mIndex");
    const uint32_t length = comp.cmp<uint32_t>("mDataLength");
    const aiPropertyTypeInfo type = static_cast<aiPropertyTypeInfo>(
        comp.cmp<uint32_t>("mType"));

    switch (type)
    {
        case aiPTI_Float:
            comp.cmp<float>(length/4,"mData");
            break;

        case aiPTI_String:
            comp.cmp<aiString>("mData");
            break;

        case aiPTI_Integer:
            comp.cmp<uint32_t>(length/4,"mData");
            break;

        case aiPTI_Buffer:
            comp.cmp<uint8_t>(length,"mData");
            break;

        default:
            break;
    };
}

////////////////////////////////////////////////////////////////////////////////////////////////////
void CompareOnTheFlyMaterial(comparer_context& comp)    {
    scoped_chunk chunk(comp,"aiMaterial");

    comp.cmp<uint32_t>("aiMaterial::mNumProperties");
    sliced_chunk_reader reader(comp);
    for(sliced_chunk_iterator it = reader.begin(); !it.is_end(); ++it) {
        if ((*it).first == ASSBIN_CHUNK_AIMATERIALPROPERTY) {
            CompareOnTheFlyMaterialProperty(comp);
        }
    }
}

////////////////////////////////////////////////////////////////////////////////////////////////////
void CompareOnTheFlyBone(comparer_context& comp)    {
    scoped_chunk chunk(comp,"aiBone");
    comp.cmp<aiString>("mName");
    comp.cmp<uint32_t>("mNumWeights");
    comp.cmp<aiMatrix4x4>("mOffsetMatrix");

    comp.cmp_bounds<aiVertexWeight>("mWeights");
}

////////////////////////////////////////////////////////////////////////////////////////////////////
void CompareOnTheFlyNodeAnim(comparer_context& comp)    {
    scoped_chunk chunk(comp,"aiNodeAnim");

    comp.cmp<aiString>("mNodeName");
    comp.cmp<uint32_t>("mNumPositionKeys");
    comp.cmp<uint32_t>("mNumRotationKeys");
    comp.cmp<uint32_t>("mNumScalingKeys");
    comp.cmp<uint32_t>("mPreState");
    comp.cmp<uint32_t>("mPostState");

    comp.cmp_bounds<aiVectorKey>("mPositionKeys");
    comp.cmp_bounds<aiQuatKey>("mRotationKeys");
    comp.cmp_bounds<aiVectorKey>("mScalingKeys");
}

////////////////////////////////////////////////////////////////////////////////////////////////////
void CompareOnTheFlyMesh(comparer_context& comp)    {
    scoped_chunk chunk(comp,"aiMesh");

    comp.cmp<uint32_t>("mPrimitiveTypes");
    comp.cmp<uint32_t>("mNumVertices");
    const uint32_t nf = comp.cmp<uint32_t>("mNumFaces");
    comp.cmp<uint32_t>("mNumBones");
    comp.cmp<uint32_t>("mMaterialIndex");

    const uint32_t present = comp.cmp<uint32_t>("<vertex-components-present>");
    if(present & ASSBIN_MESH_HAS_POSITIONS) {
        comp.cmp_bounds<aiVector3D>("mVertices");
    }

    if(present & ASSBIN_MESH_HAS_NORMALS) {
        comp.cmp_bounds<aiVector3D>("mNormals");
    }

    if(present & ASSBIN_MESH_HAS_TANGENTS_AND_BITANGENTS) {
        comp.cmp_bounds<aiVector3D>("mTangents");
        comp.cmp_bounds<aiVector3D>("mBitangents");
    }

    for(unsigned int i = 0; present & ASSBIN_MESH_HAS_COLOR(i); ++i) {
        std::stringstream ss;
        comp.cmp_bounds<aiColor4D>((ss<<"mColors["<<i<<"]",ss.str()));
    }

    for(unsigned int i = 0; present & ASSBIN_MESH_HAS_TEXCOORD(i); ++i) {
        std::stringstream ss;
        comp.cmp<uint32_t>((ss<<"mNumUVComponents["<<i<<"]",ss.str()));
        comp.cmp_bounds<aiVector3D>((ss.clear(),ss<<"mTextureCoords["<<i<<"]",ss.str()));
    }

    for(unsigned int i = 0; i< ((nf+511)/512); ++i) {
        std::stringstream ss;
        comp.cmp<uint32_t>((ss<<"mFaces["<<i*512<<"-"<<std::min(static_cast<
            uint32_t>((i+1)*512),nf)<<"]",ss.str()));
    }

    sliced_chunk_reader reader(comp);
    for(sliced_chunk_iterator it = reader.begin(); !it.is_end(); ++it) {
        if ((*it).first == ASSBIN_CHUNK_AIBONE) {
            CompareOnTheFlyBone(comp);
        }
    }
}

////////////////////////////////////////////////////////////////////////////////////////////////////
void CompareOnTheFlyCamera(comparer_context& comp)  {
    scoped_chunk chunk(comp,"aiCamera");

    comp.cmp<aiString>("mName");

    comp.cmp<aiVector3D>("mPosition");
    comp.cmp<aiVector3D>("mLookAt");
    comp.cmp<aiVector3D>("mUp");

    comp.cmp<float>("mHorizontalFOV");
    comp.cmp<float>("mClipPlaneNear");
    comp.cmp<float>("mClipPlaneFar");
    comp.cmp<float>("mAspect");
}

////////////////////////////////////////////////////////////////////////////////////////////////////
void CompareOnTheFlyLight(comparer_context& comp)   {
    scoped_chunk chunk(comp,"aiLight");

    comp.cmp<aiString>("mName");
    const aiLightSourceType type = static_cast<aiLightSourceType>(
        comp.cmp<uint32_t>("mType"));

    if(type!=aiLightSource_DIRECTIONAL) {
        comp.cmp<float>("mAttenuationConstant");
        comp.cmp<float>("mAttenuationLinear");
        comp.cmp<float>("mAttenuationQuadratic");
    }

    comp.cmp<aiVector3D>("mColorDiffuse");
    comp.cmp<aiVector3D>("mColorSpecular");
    comp.cmp<aiVector3D>("mColorAmbient");

    if(type==aiLightSource_SPOT) {
        comp.cmp<float>("mAngleInnerCone");
        comp.cmp<float>("mAngleOuterCone");
    }
}

////////////////////////////////////////////////////////////////////////////////////////////////////
void CompareOnTheFlyAnimation(comparer_context& comp)   {
    scoped_chunk chunk(comp,"aiAnimation");

    comp.cmp<aiString>("mName");
    comp.cmp<double>("mDuration");
    comp.cmp<double>("mTicksPerSecond");
    comp.cmp<uint32_t>("mNumChannels");

    sliced_chunk_reader reader(comp);
    for(sliced_chunk_iterator it = reader.begin(); !it.is_end(); ++it) {
        if ((*it).first == ASSBIN_CHUNK_AINODEANIM) {
            CompareOnTheFlyNodeAnim(comp);
        }
    }
}

////////////////////////////////////////////////////////////////////////////////////////////////////
void CompareOnTheFlyTexture(comparer_context& comp) {
    scoped_chunk chunk(comp,"aiTexture");

    const uint32_t w = comp.cmp<uint32_t>("mWidth");
    const uint32_t h = comp.cmp<uint32_t>("mHeight");
    (void)w; (void)h;
    comp.cmp<char>("achFormatHint[0]");
    comp.cmp<char>("achFormatHint[1]");
    comp.cmp<char>("achFormatHint[2]");
    comp.cmp<char>("achFormatHint[3]");
    comp.cmp<char>("achFormatHint[4]");
    comp.cmp<char>("achFormatHint[5]");
    comp.cmp<char>("achFormatHint[6]");
    comp.cmp<char>("achFormatHint[7]");
}

////////////////////////////////////////////////////////////////////////////////////////////////////
void CompareOnTheFlyNode(comparer_context& comp)    {
    scoped_chunk chunk(comp,"aiNode");
    comp.cmp<aiString>("mName");
    comp.cmp<aiMatrix4x4>("mTransformation");
    comp.cmp<uint32_t>("mNumChildren");
    comp.cmp<uint32_t>(comp.cmp<uint32_t>("mNumMeshes"),"mMeshes");

    sliced_chunk_reader reader(comp);
    for(sliced_chunk_iterator it = reader.begin(); !it.is_end(); ++it) {
        if ((*it).first == ASSBIN_CHUNK_AINODE) {
            CompareOnTheFlyNode(comp);
        }
    }
}

////////////////////////////////////////////////////////////////////////////////////////////////////
void CompareOnTheFlyScene(comparer_context& comp)   {
    scoped_chunk chunk(comp,"aiScene");

    comp.cmp<uint32_t>("mFlags");
    comp.cmp<uint32_t>("mNumMeshes");
    comp.cmp<uint32_t>("mNumMaterials");
    comp.cmp<uint32_t>("mNumAnimations");
    comp.cmp<uint32_t>("mNumTextures");
    comp.cmp<uint32_t>("mNumLights");
    comp.cmp<uint32_t>("mNumCameras");

    sliced_chunk_reader reader(comp);
    for(sliced_chunk_iterator it = reader.begin(); !it.is_end(); ++it) {
        if ((*it).first == ASSBIN_CHUNK_AIMATERIAL) {
            CompareOnTheFlyMaterial(comp);
        }
        else if ((*it).first == ASSBIN_CHUNK_AITEXTURE) {
            CompareOnTheFlyTexture(comp);
        }
        else if ((*it).first == ASSBIN_CHUNK_AIMESH) {
            CompareOnTheFlyMesh(comp);
        }
        else if ((*it).first == ASSBIN_CHUNK_AIANIMATION) {
            CompareOnTheFlyAnimation(comp);
        }
        else if ((*it).first == ASSBIN_CHUNK_AICAMERA) {
            CompareOnTheFlyCamera(comp);
        }
        else if ((*it).first == ASSBIN_CHUNK_AILIGHT) {
            CompareOnTheFlyLight(comp);
        }
        else if ((*it).first == ASSBIN_CHUNK_AINODE) {
            CompareOnTheFlyNode(comp);
        }
    }
}

////////////////////////////////////////////////////////////////////////////////////////////////////
void CompareOnTheFly(comparer_context& comp)
{
    sliced_chunk_reader reader(comp);
    for(sliced_chunk_iterator it = reader.begin(); !it.is_end(); ++it) {
        if ((*it).first == ASSBIN_CHUNK_AISCENE) {
            CompareOnTheFlyScene(comp);
            break;
        }
    }
}

////////////////////////////////////////////////////////////////////////////////////////////////////
void CheckHeader(comparer_context& comp)
{
    fseek(comp.get_actual(),ASSBIN_HEADER_LENGTH,SEEK_CUR);
    fseek(comp.get_expect(),ASSBIN_HEADER_LENGTH,SEEK_CUR);
}

////////////////////////////////////////////////////////////////////////////////////////////////////
int Assimp_CompareDump (const char* const* params, unsigned int num)
{
    // --help
    if ((num == 1 && !strcmp( params[0], "-h")) || !strcmp( params[0], "--help") || !strcmp( params[0], "-?") ) {
        printf("%s",AICMD_MSG_CMPDUMP_HELP);
        return AssimpCmdError::Success;
    }

    // assimp cmpdump actual expected
    if (num < 2) {
        std::cout << "assimp cmpdump: Invalid number of arguments. "
            "See \'assimp cmpdump --help\'\r\n" << std::endl;
        return AssimpCmdError::InvalidNumberOfArguments;
    }

    if(!strcmp(params[0],params[1])) {
        std::cout << "assimp cmpdump: same file, same content." << std::endl;
        return AssimpCmdError::Success;
    }

    class file_ptr
    {
    public:
        file_ptr(FILE *p)
            : m_file(p)
        {}
        ~file_ptr()
        {
            if (m_file)
            {
                fclose(m_file);
                m_file = nullptr;
            }
        }

        operator FILE *() { return m_file; }

    private:
        FILE *m_file;
    };
    file_ptr actual(fopen(params[0],"rb"));
    if (!actual) {
        std::cout << "assimp cmpdump: Failure reading ACTUAL data from " <<
            params[0]  << std::endl;
        return AssimpCmdError::FailedToLoadInputFile;
    }
    file_ptr expected(fopen(params[1],"rb"));
    if (!expected) {
        std::cout << "assimp cmpdump: Failure reading EXPECT data from " <<
            params[1]  << std::endl;
        return AssimpCmdCompareDumpError::FailedToLoadExpectedInputFile;
    }

    comparer_context comp(actual,expected);
    try {
        CheckHeader(comp);
        CompareOnTheFly(comp);
    }
    catch(const compare_fails_exception& ex) {
        printf("%s",ex.what());
        return AssimpCmdCompareDumpError::FileComparaisonFailure;
    }
    catch(...) {
        // we don't bother checking too rigourously here, so
        // we might end up here ...
        std::cout << "Unknown failure, are the input files well-defined?";
        return AssimpCmdCompareDumpError::UnknownFailure;
    }

    std::cout << "Success (totally " << std::dec << comp.get_num_chunks() <<
        " chunks)" << std::endl;

    return AssimpCmdError::Success;
}