Merge branch 'master' into feature/rust_bindings

Co-authored-by: coderabbitai[bot] <136622811+coderabbitai[bot]@users.noreply.github.com>

.github/workflows/ccpp.yml

@@ -182,7 +182,7 @@ jobs:
     runs-on: ubuntu-latest
     if: startsWith(github.ref, 'refs/tags/')
     steps:
-      - uses: softprops/action-gh-release@v3
+      - uses: softprops/action-gh-release@v2
         with:
           name: create-release
       - id: upload-url
@@ -197,4 +197,4 @@ jobs:
         with:
           files: |
             *.zip
- 
+ 

.github/workflows/cd.yml

@@ -45,7 +45,7 @@ jobs:
           filename: ${{ matrix.name }}-${{ github.event.release.tag_name }}.zip
           directory: build/bin/
 
-      - uses: softprops/action-gh-release@v3
+      - uses: softprops/action-gh-release@v2
         with:
           files: build/bin/${{ matrix.name }}-${{ github.event.release.tag_name }}.zip
           append_body: true

code/AssetLib/Assbin/AssbinLoader.cpp

@@ -149,18 +149,11 @@ aiQuaternion Read<aiQuaternion>(IOStream *stream) {
 template <>
 aiString Read<aiString>(IOStream *stream) {
     aiString s;
-    uint32_t len;
-    if (stream->Read(&len, 4, 1) != 1) {
-        throw DeadlyImportError("ASSBIN: Unexpected EOF reading string length");
+    stream->Read(&s.length, 4, 1);
+    if (s.length) {
+        stream->Read(s.data, s.length, 1);
     }
-    if (len >= AI_MAXLEN) {
-        throw DeadlyImportError("ASSBIN: String length too large, potential buffer overflow attempt");
-    }
-    s.length = len;
-    if ((s.length > 0) && (stream->Read(s.data, s.length, 1) != 1)) {
-        throw DeadlyImportError("ASSBIN: Unexpected EOF reading string data");
-    }
-    s.data[s.length] = '\0';
+    s.data[s.length] = 0;
 
     return s;
 }

code/AssetLib/Collada/ColladaLoader.cpp

@@ -507,20 +507,16 @@ void ColladaLoader::BuildMeshesForNode(const ColladaParser &pParser, const Node
             }
 
             if (table && !table->mMap.empty()) {
-                if (matIdx < newMats.size()) {
-                    std::pair<Collada::Effect *, aiMaterial *> &mat = newMats[matIdx];
+                std::pair<Collada::Effect *, aiMaterial *> &mat = newMats[matIdx];
 
-                    // Iterate through all texture channels assigned to the effect and
-                    // check whether we have mapping information for it.
-                    ApplyVertexToEffectSemanticMapping(mat.first->mTexDiffuse, *table);
-                    ApplyVertexToEffectSemanticMapping(mat.first->mTexAmbient, *table);
-                    ApplyVertexToEffectSemanticMapping(mat.first->mTexSpecular, *table);
-                    ApplyVertexToEffectSemanticMapping(mat.first->mTexEmissive, *table);
-                    ApplyVertexToEffectSemanticMapping(mat.first->mTexTransparent, *table);
-                    ApplyVertexToEffectSemanticMapping(mat.first->mTexBump, *table);
-                } else {
-                    ASSIMP_LOG_WARN("Collada: Ignoring material mapping for mesh \"", mid.mMeshOrController, "\". Material index ", matIdx, " is out of bounds (newMats.size()=", newMats.size(), ").");
-                }
+                // Iterate through all texture channels assigned to the effect and
+                // check whether we have mapping information for it.
+                ApplyVertexToEffectSemanticMapping(mat.first->mTexDiffuse, *table);
+                ApplyVertexToEffectSemanticMapping(mat.first->mTexAmbient, *table);
+                ApplyVertexToEffectSemanticMapping(mat.first->mTexSpecular, *table);
+                ApplyVertexToEffectSemanticMapping(mat.first->mTexEmissive, *table);
+                ApplyVertexToEffectSemanticMapping(mat.first->mTexTransparent, *table);
+                ApplyVertexToEffectSemanticMapping(mat.first->mTexBump, *table);
             }
 
             // built lookup index of the Mesh-Submesh-Material combination

code/AssetLib/FBX/FBXDeformer.cpp

@@ -45,8 +45,6 @@ OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 #ifndef ASSIMP_BUILD_NO_FBX_IMPORTER
 
-#include <algorithm>
-
 #include "FBXParser.h"
 #include "FBXDocument.h"
 #include "FBXMeshGeometry.h"
@@ -146,10 +144,8 @@ BlendShape::BlendShape(uint64_t id, const Element& element, const Document& doc,
     for (const Connection* con : conns) {
         const BlendShapeChannel* const bspc = ProcessSimpleConnection<BlendShapeChannel>(*con, false, "BlendShapeChannel -> BlendShape", element);
         if (bspc) {
-            // Only add a channel if it doesn't exist already
-            if (std::find(blendShapeChannels.begin(), blendShapeChannels.end(), bspc) == blendShapeChannels.end()) {
-                blendShapeChannels.push_back(bspc);
-            } else {
+            auto pr = blendShapeChannels.insert(bspc);
+            if (!pr.second) {
                 FBXImporter::LogWarn("there is the same blendShapeChannel id ", bspc->ID());
             }
         }
@@ -174,10 +170,8 @@ BlendShapeChannel::BlendShapeChannel(uint64_t id, const Element& element, const
     for (const Connection* con : conns) {
         const ShapeGeometry* const sg = ProcessSimpleConnection<ShapeGeometry>(*con, false, "Shape -> BlendShapeChannel", element);
         if (sg) {
-            // Only add a geometry if it doesn't exist already
-            if (std::find(shapeGeometries.begin(), shapeGeometries.end(), sg) == shapeGeometries.end()) {
-                shapeGeometries.push_back(sg);
-            } else {
+            auto pr = shapeGeometries.insert(sg);
+            if (!pr.second) {
                 FBXImporter::LogWarn("there is the same shapeGeometrie id ", sg->ID());
             }
         }

code/AssetLib/FBX/FBXDocument.h

@@ -865,14 +865,14 @@ public:
         return fullWeights;
     }
 
-    const std::vector<const ShapeGeometry*>& GetShapeGeometries() const {
+    const std::unordered_set<const ShapeGeometry*>& GetShapeGeometries() const {
         return shapeGeometries;
     }
 
 private:
     float percent;
     WeightArray fullWeights;
-    std::vector<const ShapeGeometry*> shapeGeometries;
+    std::unordered_set<const ShapeGeometry*> shapeGeometries;
 };
 
 /** DOM class for BlendShape deformers */
@@ -882,12 +882,12 @@ public:
 
     virtual ~BlendShape() = default;
 
-    const std::vector<const BlendShapeChannel*>& BlendShapeChannels() const {
+    const std::unordered_set<const BlendShapeChannel*>& BlendShapeChannels() const {
         return blendShapeChannels;
     }
 
 private:
-    std::vector<const BlendShapeChannel*> blendShapeChannels;
+    std::unordered_set<const BlendShapeChannel*> blendShapeChannels;
 };
 
 /** DOM class for skin deformer clusters (aka sub-deformers) */

code/AssetLib/FBX/FBXImporter.cpp

@@ -90,7 +90,7 @@ namespace {
 // Returns whether the class can handle the format of the given file.
 bool FBXImporter::CanRead(const std::string & pFile, IOSystem * pIOHandler, bool /*checkSig*/) const {
 	// at least ASCII-FBX files usually have a 'FBX' somewhere in their head
-	static const char *tokens[] = { " \n\r\n ", "fbx" };
+	static const char *tokens[] = { " \n\r\n " };
 	return SearchFileHeaderForToken(pIOHandler, pFile, tokens, AI_COUNT_OF(tokens));
 }
 

code/AssetLib/FBX/FBXMeshGeometry.cpp

@@ -45,7 +45,6 @@ OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 #ifndef ASSIMP_BUILD_NO_FBX_IMPORTER
 
-#include <algorithm>
 #include <functional>
 
 #include "FBXMeshGeometry.h"
@@ -70,10 +69,8 @@ Geometry::Geometry(uint64_t id, const Element& element, const std::string& name,
         }
         const BlendShape* const bsp = ProcessSimpleConnection<BlendShape>(*con, false, "BlendShape -> Geometry", element);
         if (bsp) {
-            // Only add a blendshape if it doesn't exist already
-            if (std::find(blendShapes.begin(), blendShapes.end(), bsp) == blendShapes.end()) {
-                blendShapes.push_back(bsp);
-            } else {
+            auto pr = blendShapes.insert(bsp);
+            if (!pr.second) {
                 FBXImporter::LogWarn("there is the same blendShape id ", bsp->ID());
             }
         }
@@ -81,7 +78,7 @@ Geometry::Geometry(uint64_t id, const Element& element, const std::string& name,
 }
 
 // ------------------------------------------------------------------------------------------------
-const std::vector<const BlendShape*>& Geometry::GetBlendShapes() const {
+const std::unordered_set<const BlendShape*>& Geometry::GetBlendShapes() const {
     return blendShapes;
 }
 

code/AssetLib/FBX/FBXMeshGeometry.h

@@ -72,11 +72,11 @@ public:
 
     /// @brief Get the BlendShape attached to this geometry or nullptr
     /// @return The blendshape arrays.
-    const std::vector<const BlendShape*>& GetBlendShapes() const;
+    const std::unordered_set<const BlendShape*>& GetBlendShapes() const;
 
 private:
     const Skin* skin;
-    std::vector<const BlendShape*> blendShapes;
+    std::unordered_set<const BlendShape*> blendShapes;
 
 };
 

code/AssetLib/M3D/M3DWrapper.cpp

@@ -36,6 +36,7 @@ DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
 ----------------------------------------------------------------------
 */
 #if !defined ASSIMP_BUILD_NO_M3D_IMPORTER || !(defined ASSIMP_BUILD_NO_EXPORT || defined ASSIMP_BUILD_NO_M3D_EXPORTER)
@@ -102,68 +103,15 @@ M3DWrapper::M3DWrapper(IOSystem *pIOHandler, const std::vector<unsigned char> &b
         ai_assert(nullptr != pIOHandler);
     }
 
-    // Security fix: Validate buffer size and content before processing
-    if (buffer.empty()) {
-        ASSIMP_LOG_ERROR("M3D: Empty buffer provided");
-        m3d_ = nullptr;
-        return;
-    }
-
-    // Check for minimum valid M3D file size (header + basic structure)
-    const size_t MIN_VALID_M3D_SIZE = 100; // Minimum reasonable size for a valid M3D file
-    if (buffer.size() < MIN_VALID_M3D_SIZE) {
-        ASSIMP_LOG_ERROR("M3D: Buffer too small to be a valid M3D file");
-        m3d_ = nullptr;
-        return;
-    }
-
-    // Validate M3D magic signature to ensure this is actually an M3D file
-    // M3D files should start with "3DMO" or "3dmo" magic signature
-    if (buffer.size() >= 4) {
-        bool valid_signature = false;
-        // Check for "3DMO" (uppercase)
-        if (buffer[0] == '3' && buffer[1] == 'D' && buffer[2] == 'M' && buffer[3] == 'O') {
-            valid_signature = true;
-        }
-        // Check for "3dmo" (lowercase)
-        else if (buffer[0] == '3' && buffer[1] == 'd' && buffer[2] == 'm' && buffer[3] == 'o') {
-            valid_signature = true;
-        }
-        
-        if (!valid_signature) {
-            ASSIMP_LOG_ERROR("M3D: Invalid file signature - not a valid M3D file");
-            m3d_ = nullptr;
-            return;
-        }
-    }
-
-    // Create a safe copy of the buffer with guard pages/validation
-    // This helps prevent buffer overflows from affecting the main process
-    std::vector<unsigned char> safe_buffer = buffer;
-    
-    // Add a guard page at the end to catch any overflow attempts
-    // Note: This is a defensive measure, not a complete fix for the underlying issue
-    safe_buffer.resize(safe_buffer.size() + 1);
-    safe_buffer.back() = 0xFF; // Guard byte
-
 #ifdef ASSIMP_USE_M3D_READFILECB
     // pass this IOHandler to the C callback in a thread-local pointer
     m3dimporter_pIOHandler = pIOHandler;
-    m3d_ = m3d_load(const_cast<unsigned char *>(safe_buffer.data()), m3dimporter_readfile, free, nullptr);
+    m3d_ = m3d_load(const_cast<unsigned char *>(buffer.data()), m3dimporter_readfile, free, nullptr);
     // Clear the C callback
     m3dimporter_pIOHandler = nullptr;
 #else
-    m3d_ = m3d_load(const_cast<unsigned char *>(safe_buffer.data()), nullptr, nullptr, nullptr);
+    m3d_ = m3d_load(const_cast<unsigned char *>(buffer.data()), nullptr, nullptr, nullptr);
 #endif
-
-    // Verify the guard byte wasn't overwritten (indicating potential buffer overflow)
-    if (safe_buffer.empty() || safe_buffer.back() != 0xFF) {
-        ASSIMP_LOG_ERROR("M3D: Potential buffer overflow detected during loading");
-        if (m3d_) {
-            m3d_free(m3d_);
-            m3d_ = nullptr;
-        }
-    }
 }
 
 M3DWrapper::~M3DWrapper() {
@@ -199,4 +147,4 @@ void M3DWrapper::ClearSave() {
 }
 } // namespace Assimp
 
-#endif
+#endif

code/AssetLib/M3D/M3DWrapper.h

@@ -72,7 +72,7 @@ public:
 
 	/// Construct an M3D model from provided buffer
 	/// @note The m3d.h SDK function does not mark the data as const. Have assumed it does not write.
-	/// SECURITY: Buffer size validation and guard pages added to mitigate potential overflows
+	/// BUG: SECURITY: The m3d.h SDK cannot be informed of the buffer size. BUFFER OVERFLOW IS CERTAIN
 	explicit M3DWrapper(IOSystem *pIOHandler, const std::vector<unsigned char> &buffer);
 
 	/// Theclasss destructor.

code/AssetLib/glTF2/glTF2Asset.inl

@@ -1038,27 +1038,21 @@ size_t Accessor::ExtractData(T *&outData, const std::vector<unsigned int> *remap
 
     const size_t maxSize = GetMaxByteSize();
 
-    if (elemSize > maxSize) {
-        throw DeadlyImportError("GLTF: elemSize ", elemSize, " > maxSize ", maxSize, " in ", getContextForErrorMessages(id, name));
-    }
-
-    const size_t maxCount = (maxSize - elemSize) / stride + 1;
-
-    if (count > maxCount) {
-        throw DeadlyImportError("GLTF: count ", count, " > maxCount ", maxCount, " in ", getContextForErrorMessages(id, name));
-    }
-
     outData = new T[usedCount];
 
     if (remappingIndices != nullptr) {
+        const unsigned int maxIndexCount = static_cast<unsigned int>(maxSize / stride);
         for (size_t i = 0; i < usedCount; ++i) {
             size_t srcIdx = (*remappingIndices)[i];
-            if (srcIdx >= count) {
-                throw DeadlyImportError("GLTF: index ", srcIdx, " >= count ", count, " in ", getContextForErrorMessages(id, name));
+            if (srcIdx >= maxIndexCount) {
+                throw DeadlyImportError("GLTF: index*stride ", (srcIdx * stride), " > maxSize ", maxSize, " in ", getContextForErrorMessages(id, name));
             }
             memcpy(outData + i, data + srcIdx * stride, elemSize);
         }
     } else { // non-indexed cases
+        if (usedCount * stride > maxSize) {
+            throw DeadlyImportError("GLTF: count*stride ", (usedCount * stride), " > maxSize ", maxSize, " in ", getContextForErrorMessages(id, name));
+        }
         if (stride == elemSize && targetElemSize == elemSize) {
             memcpy(outData, data, totalSize);
         } else {

code/AssetLib/glTF2/glTF2Exporter.cpp

@@ -556,6 +556,12 @@ void glTF2Exporter::GetMatTexProp(const aiMaterial &mat, unsigned int &prop, con
     mat.Get(textureKey.c_str(), tt, slot, prop);
 }
 
+void glTF2Exporter::GetMatTexProp(const aiMaterial &mat, float &prop, const char *propName, aiTextureType tt, unsigned int slot) {
+    std::string textureKey = std::string(_AI_MATKEY_TEXTURE_BASE) + "." + propName;
+
+    mat.Get(textureKey.c_str(), tt, slot, prop);
+}
+
 void glTF2Exporter::GetMatTex(const aiMaterial &mat, Ref<Texture> &texture, unsigned int &texCoord, aiTextureType tt, unsigned int slot = 0) {
     if (mat.GetTextureCount(tt) == 0) {
         return;
@@ -646,7 +652,7 @@ void glTF2Exporter::GetMatTex(const aiMaterial &mat, NormalTextureInfo &prop, ai
 
     if (texture) {
         // GetMatTexProp(mat, prop.texCoord, "texCoord", tt, slot);
-        mat.Get(AI_MATKEY_GLTF_TEXTURE_SCALE(tt, slot), prop.scale);
+        GetMatTexProp(mat, prop.scale, "scale", tt, slot);
     }
 }
 
@@ -657,7 +663,7 @@ void glTF2Exporter::GetMatTex(const aiMaterial &mat, OcclusionTextureInfo &prop,
 
     if (texture) {
         // GetMatTexProp(mat, prop.texCoord, "texCoord", tt, slot);
-        mat.Get(AI_MATKEY_GLTF_TEXTURE_STRENGTH(tt, slot), prop.strength);
+        GetMatTexProp(mat, prop.strength, "strength", tt, slot);
     }
 }
 

code/AssetLib/glTF2/glTF2Exporter.h

@@ -110,6 +110,7 @@ protected:
     void WriteBinaryData(IOStream *outfile, std::size_t sceneLength);
     void GetTexSampler(const aiMaterial &mat, glTFCommon::Ref<glTF2::Texture> texture, aiTextureType tt, unsigned int slot);
     void GetMatTexProp(const aiMaterial &mat, unsigned int &prop, const char *propName, aiTextureType tt, unsigned int idx);
+    void GetMatTexProp(const aiMaterial &mat, float &prop, const char *propName, aiTextureType tt, unsigned int idx);
     void GetMatTex(const aiMaterial &mat, glTFCommon::Ref<glTF2::Texture> &texture, unsigned int &texCoord, aiTextureType tt, unsigned int slot);
     void GetMatTex(const aiMaterial &mat, glTF2::TextureInfo &prop, aiTextureType tt, unsigned int slot);
     void GetMatTex(const aiMaterial &mat, glTF2::NormalTextureInfo &prop, aiTextureType tt, unsigned int slot);

code/AssetLib/glTF2/glTF2Importer.cpp

@@ -237,7 +237,8 @@ static void SetMaterialTextureProperty(std::vector<int> &embeddedTexIdxs, Asset
     SetMaterialTextureProperty(embeddedTexIdxs, r, static_cast<TextureInfo>(prop), mat, texType, texSlot);
 
     if (prop.texture && prop.texture->source) {
-        mat->AddProperty(&prop.strength, 1, AI_MATKEY_GLTF_TEXTURE_STRENGTH(texType, texSlot));
+        std::string textureStrengthKey = std::string(_AI_MATKEY_TEXTURE_BASE) + "." + "strength";
+        mat->AddProperty(&prop.strength, 1, textureStrengthKey.c_str(), texType, texSlot);
     }
 }
 

code/PostProcessing/ImproveCacheLocality.cpp

@@ -58,55 +58,11 @@ OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 #include <stack>
 
 namespace Assimp {
-namespace {
-    ai_real calculateInputACMR(aiMesh *pMesh, const aiFace *const pcEnd,
-            unsigned int configCacheDepth, unsigned int meshNum) {
-        ai_real fACMR = 0.0f;
-        unsigned int *piFIFOStack = new unsigned int[configCacheDepth];
-        memset(piFIFOStack, 0xff, configCacheDepth * sizeof(unsigned int));
-        unsigned int *piCur = piFIFOStack;
-        const unsigned int *const piCurEnd = piFIFOStack + configCacheDepth;
-
-        // count the number of cache misses
-        unsigned int iCacheMisses = 0;
-        for (const aiFace *pcFace = pMesh->mFaces; pcFace != pcEnd; ++pcFace) {
-            for (unsigned int qq = 0; qq < 3; ++qq) {
-                bool bInCache = false;
-                for (unsigned int *pp = piFIFOStack; pp < piCurEnd; ++pp) {
-                    if (*pp == pcFace->mIndices[qq]) {
-                        // the vertex is in cache
-                        bInCache = true;
-                        break;
-                    }
-                }
-                if (!bInCache) {
-                    ++iCacheMisses;
-                    if (piCurEnd == piCur) {
-                        piCur = piFIFOStack;
-                    }
-                    *piCur++ = pcFace->mIndices[qq];
-                }
-            }
-        }
-        delete[] piFIFOStack;
-        fACMR = (ai_real)iCacheMisses / pMesh->mNumFaces;
-        if (3.0 == fACMR) {
-            char szBuff[128]; // should be sufficiently large in every case
-
-            // the JoinIdenticalVertices process has not been executed on this
-            // mesh, otherwise this value would normally be at least minimally
-            // smaller than 3.0 ...
-            ai_snprintf(szBuff, 128, "Mesh %u: Not suitable for vcache optimization", meshNum);
-            ASSIMP_LOG_WARN(szBuff);
-            return static_cast<ai_real>(0.f);
-        }
-        return fACMR;
-    }
-}
 
 // ------------------------------------------------------------------------------------------------
 // Constructor to be privately used by Importer
-ImproveCacheLocalityProcess::ImproveCacheLocalityProcess() : mConfigCacheDepth(PP_ICL_PTCACHE_SIZE) {
+ImproveCacheLocalityProcess::ImproveCacheLocalityProcess() :
+        mConfigCacheDepth(PP_ICL_PTCACHE_SIZE) {
     // empty
 }
 
@@ -151,6 +107,51 @@ void ImproveCacheLocalityProcess::Execute(aiScene *pScene) {
     }
 }
 
+// ------------------------------------------------------------------------------------------------
+static ai_real calculateInputACMR(aiMesh *pMesh, const aiFace *const pcEnd,
+        unsigned int configCacheDepth, unsigned int meshNum) {
+    ai_real fACMR = 0.0f;
+    unsigned int *piFIFOStack = new unsigned int[configCacheDepth];
+    memset(piFIFOStack, 0xff, configCacheDepth * sizeof(unsigned int));
+    unsigned int *piCur = piFIFOStack;
+    const unsigned int *const piCurEnd = piFIFOStack + configCacheDepth;
+
+    // count the number of cache misses
+    unsigned int iCacheMisses = 0;
+    for (const aiFace *pcFace = pMesh->mFaces; pcFace != pcEnd; ++pcFace) {
+        for (unsigned int qq = 0; qq < 3; ++qq) {
+            bool bInCache = false;
+            for (unsigned int *pp = piFIFOStack; pp < piCurEnd; ++pp) {
+                if (*pp == pcFace->mIndices[qq]) {
+                    // the vertex is in cache
+                    bInCache = true;
+                    break;
+                }
+            }
+            if (!bInCache) {
+                ++iCacheMisses;
+                if (piCurEnd == piCur) {
+                    piCur = piFIFOStack;
+                }
+                *piCur++ = pcFace->mIndices[qq];
+            }
+        }
+    }
+    delete[] piFIFOStack;
+    fACMR = (ai_real)iCacheMisses / pMesh->mNumFaces;
+    if (3.0 == fACMR) {
+        char szBuff[128]; // should be sufficiently large in every case
+
+        // the JoinIdenticalVertices process has not been executed on this
+        // mesh, otherwise this value would normally be at least minimally
+        // smaller than 3.0 ...
+        ai_snprintf(szBuff, 128, "Mesh %u: Not suitable for vcache optimization", meshNum);
+        ASSIMP_LOG_WARN(szBuff);
+        return static_cast<ai_real>(0.f);
+    }
+    return fACMR;
+}
+
 // ------------------------------------------------------------------------------------------------
 // Improves the cache coherency of a specific mesh
 ai_real ImproveCacheLocalityProcess::ProcessMesh(aiMesh *pMesh, unsigned int meshNum) {

include/assimp/StreamReader.h

@@ -182,7 +182,7 @@ public:
     // ---------------------------------------------------------------------
     /// Get the remaining stream size (to the end of the stream)
     size_t GetRemainingSize() const {
-        return static_cast<size_t>(mEnd - mCurrent);
+        return (unsigned int)(mEnd - mCurrent);
     }
 
     // ---------------------------------------------------------------------
@@ -190,29 +190,16 @@ public:
      *  return value is the remaining size of the stream if no custom
      *  read limit has been set. */
     size_t GetRemainingSizeToLimit() const {
-        return static_cast<size_t>(mLimit - mCurrent);
+        return (unsigned int)(mLimit - mCurrent);
     }
 
     // ---------------------------------------------------------------------
     /** Increase the file pointer (relative seeking)  */
     void IncPtr(intptr_t plus) {
-        // Ensure internal pointer invariants hold
-        if (mCurrent < mBuffer || mCurrent > mLimit) {
-            throw DeadlyImportError("StreamReader: Invalid internal pointer state");
-        }
-
-        if (plus < 0) {
-            const size_t absPlus = static_cast<size_t>(-(plus + 1)) + 1;
-            if (absPlus > static_cast<size_t>(mCurrent - mBuffer)) {
-                throw DeadlyImportError("StreamReader: Attempted to seek outside buffer bounds");
-            }
-        } else if (plus > 0) {
-            if (static_cast<size_t>(plus) > static_cast<size_t>(mLimit - mCurrent)) {
-                throw DeadlyImportError("StreamReader: Attempted to seek outside buffer bounds");
-            }
-        }
-
         mCurrent += plus;
+        if (mCurrent > mLimit) {
+            throw DeadlyImportError("End of file or read limit was reached");
+        }
     }
 
     // ---------------------------------------------------------------------
@@ -246,9 +233,8 @@ public:
     }
 
     /// @brief Get the current offset from the beginning of the file
-    /// @return The current offset from the beginning of the file.
     int GetCurrentPos() const {
-        return static_cast<int>(mCurrent - mBuffer);
+        return (unsigned int)(mCurrent - mBuffer);
     }
 
     void SetCurrentPos(size_t pos) {
@@ -258,10 +244,10 @@ public:
     // ---------------------------------------------------------------------
     /** Setup a temporary read limit
      *
-     *  @param _limit Maximum number of bytes to be read from
+     *  @param limit Maximum number of bytes to be read from
      *    the beginning of the file. Specifying UINT_MAX
      *    resets the limit to the original end of the stream.
-     *  @return The previously set limit. */
+     *  Returns the previously set limit. */
     unsigned int SetReadLimit(unsigned int _limit) {
         unsigned int prev = GetReadLimit();
         if (UINT_MAX == _limit) {
@@ -278,10 +264,9 @@ public:
 
     // ---------------------------------------------------------------------
     /** Get the current read limit in bytes. Reading over this limit
-     *  accidentally raises an exception.
-     *  @return The current limit. */
+     *  accidentally raises an exception.  */
     unsigned int GetReadLimit() const {
-        return static_cast<unsigned int>(mLimit - mBuffer);
+        return (unsigned int)(mLimit - mBuffer);
     }
 
     // ---------------------------------------------------------------------