diff --git a/code/3DSConverter.cpp b/code/3DSConverter.cpp
index 081da1bcf..e07ca4c2d 100644
--- a/code/3DSConverter.cpp
+++ b/code/3DSConverter.cpp
@@ -120,7 +120,7 @@ void Discreet3DSImporter::ReplaceDefaultMaterial()
             else if ( (*a) >= mScene->mMaterials.size())
             {
                 (*a) = idx;
-                DefaultLogger::get()->warn("Material index overflow in 3DS file. Using default material");
+                ASSIMP_LOG_WARN("Material index overflow in 3DS file. Using default material");
                 ++cnt;
             }
         }
@@ -132,7 +132,7 @@ void Discreet3DSImporter::ReplaceDefaultMaterial()
         sMat.mDiffuse = aiColor3D(0.3f,0.3f,0.3f);
         mScene->mMaterials.push_back(sMat);
 
-        DefaultLogger::get()->info("3DS: Generating default material");
+        ASSIMP_LOG_INFO("3DS: Generating default material");
     }
 }
 
@@ -147,12 +147,12 @@ void Discreet3DSImporter::CheckIndices(D3DS::Mesh& sMesh)
         {
             if ((*i).mIndices[a] >= sMesh.mPositions.size())
             {
-                DefaultLogger::get()->warn("3DS: Vertex index overflow)");
+                ASSIMP_LOG_WARN("3DS: Vertex index overflow)");
                 (*i).mIndices[a] = (uint32_t)sMesh.mPositions.size()-1;
             }
             if ( !sMesh.mTexCoords.empty() && (*i).mIndices[a] >= sMesh.mTexCoords.size())
             {
-                DefaultLogger::get()->warn("3DS: Texture coordinate index overflow)");
+                ASSIMP_LOG_WARN("3DS: Texture coordinate index overflow)");
                 (*i).mIndices[a] = (uint32_t)sMesh.mTexCoords.size()-1;
             }
         }
@@ -497,7 +497,7 @@ void Discreet3DSImporter::AddNodeToGraph(aiScene* pcSOut,aiNode* pcOut,
                         pvCurrent->x *= -1.f;
                         t2->x *= -1.f;
                     }
-                    DefaultLogger::get()->info("3DS: Flipping mesh X-Axis");
+                    ASSIMP_LOG_INFO("3DS: Flipping mesh X-Axis");
                 }
 
                 // Handle pivot point
@@ -573,11 +573,11 @@ void Discreet3DSImporter::AddNodeToGraph(aiScene* pcSOut,aiNode* pcOut,
         pcIn->aTargetPositionKeys.size() > 1)
     {
         aiAnimation* anim = pcSOut->mAnimations[0];
-        ai_assert(NULL != anim);
+        ai_assert(nullptr != anim);
 
         if (pcIn->aCameraRollKeys.size() > 1)
         {
-            DefaultLogger::get()->debug("3DS: Converting camera roll track ...");
+            ASSIMP_LOG_DEBUG("3DS: Converting camera roll track ...");
 
             // Camera roll keys - in fact they're just rotations
             // around the camera's z axis. The angles are given
@@ -597,7 +597,7 @@ void Discreet3DSImporter::AddNodeToGraph(aiScene* pcSOut,aiNode* pcOut,
 #if 0
         if (pcIn->aTargetPositionKeys.size() > 1)
         {
-            DefaultLogger::get()->debug("3DS: Converting target track ...");
+            ASSIMP_LOG_DEBUG("3DS: Converting target track ...");
 
             // Camera or spot light - need to convert the separate
             // target position channel to our representation
@@ -743,7 +743,7 @@ void Discreet3DSImporter::GenerateNodeGraph(aiScene* pcOut)
         //   |       |       |            |         |
         // MESH_0  MESH_1  MESH_2  ...  MESH_N    CAMERA_0 ....
         //
-        DefaultLogger::get()->warn("No hierarchy information has been found in the file. ");
+        ASSIMP_LOG_WARN("No hierarchy information has been found in the file. ");
 
         pcOut->mRootNode->mNumChildren = pcOut->mNumMeshes +
             static_cast<unsigned int>(mScene->mCameras.size() + mScene->mLights.size());
diff --git a/code/3DSExporter.cpp b/code/3DSExporter.cpp
index fcd24d8aa..53976b16f 100644
--- a/code/3DSExporter.cpp
+++ b/code/3DSExporter.cpp
@@ -381,7 +381,7 @@ void Discreet3DSExporter::WriteTexture(const aiMaterial& mat, aiTextureType type
 
     // TODO: handle embedded textures properly
     if (path.data[0] == '*') {
-        DefaultLogger::get()->error("Ignoring embedded texture for export: " + std::string(path.C_Str()));
+        ASSIMP_LOG_ERROR("Ignoring embedded texture for export: " + std::string(path.C_Str()));
         return;
     }
 
diff --git a/code/3DSLoader.cpp b/code/3DSLoader.cpp
index bfe2bf6e5..3c95d8193 100644
--- a/code/3DSLoader.cpp
+++ b/code/3DSLoader.cpp
@@ -258,8 +258,9 @@ void Discreet3DSImporter::ReadChunk(Discreet3DS::Chunk* pcOut)
     if (pcOut->Size - sizeof(Discreet3DS::Chunk) > stream->GetRemainingSize())
         throw DeadlyImportError("Chunk is too large");
 
-    if (pcOut->Size - sizeof(Discreet3DS::Chunk) > stream->GetRemainingSizeToLimit())
-        DefaultLogger::get()->error("3DS: Chunk overflow");
+    if (pcOut->Size - sizeof(Discreet3DS::Chunk) > stream->GetRemainingSizeToLimit()) {
+        ASSIMP_LOG_ERROR("3DS: Chunk overflow");
+    }
 }
 
 // ------------------------------------------------------------------------------------------------
@@ -320,7 +321,7 @@ void Discreet3DSImporter::ParseEditorChunk()
         // print the version number
         char buff[10];
         ASSIMP_itoa10(buff,stream->GetI2());
-        DefaultLogger::get()->info(std::string("3DS file format version: ") + buff);
+        ASSIMP_LOG_INFO_F(std::string("3DS file format version: "), buff);
         }
         break;
     };
@@ -361,7 +362,7 @@ void Discreet3DSImporter::ParseObjectChunk()
         if (is_qnan(mClrAmbient.r))
         {
             // We failed to read the ambient base color.
-            DefaultLogger::get()->error("3DS: Failed to read ambient base color");
+            ASSIMP_LOG_ERROR("3DS: Failed to read ambient base color");
             mClrAmbient.r = mClrAmbient.g = mClrAmbient.b = 0.0f;
         }
         break;
@@ -463,7 +464,7 @@ void Discreet3DSImporter::ParseChunk(const char* name, unsigned int num)
         if (len < 1e-5) {
 
             // There are some files with lookat == position. Don't know why or whether it's ok or not.
-            DefaultLogger::get()->error("3DS: Unable to read proper camera look-at vector");
+            ASSIMP_LOG_ERROR("3DS: Unable to read proper camera look-at vector");
             camera->mLookAt = aiVector3D(0.0,1.0,0.0);
 
         }
@@ -629,9 +630,9 @@ void Discreet3DSImporter::SkipTCBInfo()
     if (!flags) {
         // Currently we can't do anything with these values. They occur
         // quite rare, so it wouldn't be worth the effort implementing
-        // them. 3DS ist not really suitable for complex animations,
+        // them. 3DS is not really suitable for complex animations,
         // so full support is not required.
-        DefaultLogger::get()->warn("3DS: Skipping TCB animation info");
+        ASSIMP_LOG_WARN("3DS: Skipping TCB animation info");
     }
 
     if (flags & Discreet3DS::KEY_USE_TENS) {
@@ -732,7 +733,6 @@ void Discreet3DSImporter::ParseHierarchyChunk(uint16_t parent)
 
             // If object name is DUMMY, take this one instead
             if (mCurrentNode->mName == "$$$DUMMY")  {
-                //DefaultLogger::get()->warn("3DS: Skipping dummy object name for non-dummy object");
                 mCurrentNode->mName = std::string(sz);
                 break;
             }
@@ -743,7 +743,7 @@ void Discreet3DSImporter::ParseHierarchyChunk(uint16_t parent)
 
         if ( Discreet3DS::CHUNK_TRACKINFO != parent)
         {
-            DefaultLogger::get()->warn("3DS: Skipping pivot subchunk for non usual object");
+            ASSIMP_LOG_WARN("3DS: Skipping pivot subchunk for non usual object");
             break;
         }
 
@@ -805,7 +805,7 @@ void Discreet3DSImporter::ParseHierarchyChunk(uint16_t parent)
         {
         // roll keys are accepted for cameras only
         if (parent != Discreet3DS::CHUNK_TRACKCAMERA)   {
-            DefaultLogger::get()->warn("3DS: Ignoring roll track for non-camera object");
+            ASSIMP_LOG_WARN("3DS: Ignoring roll track for non-camera object");
             break;
         }
         bool sortKeys = false;
@@ -845,7 +845,7 @@ void Discreet3DSImporter::ParseHierarchyChunk(uint16_t parent)
         // CAMERA FOV KEYFRAME
     case Discreet3DS::CHUNK_TRACKFOV:
         {
-            DefaultLogger::get()->error("3DS: Skipping FOV animation track. "
+            ASSIMP_LOG_ERROR("3DS: Skipping FOV animation track. "
                 "This is not supported");
         }
         break;
@@ -985,7 +985,7 @@ void Discreet3DSImporter::ParseFaceChunk()
             }
         }
         if (0xcdcdcdcd == idx)  {
-            DefaultLogger::get()->error(std::string("3DS: Unknown material: ") + sz);
+            ASSIMP_LOG_ERROR_F( "3DS: Unknown material: ", sz);
         }
 
         // Now continue and read all material indices
@@ -995,7 +995,7 @@ void Discreet3DSImporter::ParseFaceChunk()
 
             // check range
             if (fidx >= mMesh.mFaceMaterials.size())    {
-                DefaultLogger::get()->error("3DS: Invalid face index in face material list");
+                ASSIMP_LOG_ERROR("3DS: Invalid face index in face material list");
             }
             else mMesh.mFaceMaterials[fidx] = idx;
         }}
@@ -1110,7 +1110,7 @@ void Discreet3DSImporter::ParseMaterialChunk()
 
         if (!cnt)   {
             // This may not be, we use the default name instead
-            DefaultLogger::get()->error("3DS: Empty material name");
+            ASSIMP_LOG_ERROR("3DS: Empty material name");
         }
         else mScene->mMaterials.back().mName = std::string(sz,cnt);
         }
@@ -1123,7 +1123,7 @@ void Discreet3DSImporter::ParseMaterialChunk()
         ParseColorChunk(pc);
         if (is_qnan(pc->r)) {
             // color chunk is invalid. Simply ignore it
-            DefaultLogger::get()->error("3DS: Unable to read DIFFUSE chunk");
+            ASSIMP_LOG_ERROR("3DS: Unable to read DIFFUSE chunk");
             pc->r = pc->g = pc->b = 1.0f;
         }}
         break;
@@ -1135,7 +1135,7 @@ void Discreet3DSImporter::ParseMaterialChunk()
         ParseColorChunk(pc);
         if (is_qnan(pc->r)) {
             // color chunk is invalid. Simply ignore it
-            DefaultLogger::get()->error("3DS: Unable to read SPECULAR chunk");
+            ASSIMP_LOG_ERROR("3DS: Unable to read SPECULAR chunk");
             pc->r = pc->g = pc->b = 1.0f;
         }}
         break;
@@ -1147,7 +1147,7 @@ void Discreet3DSImporter::ParseMaterialChunk()
         ParseColorChunk(pc);
         if (is_qnan(pc->r)) {
             // color chunk is invalid. Simply ignore it
-            DefaultLogger::get()->error("3DS: Unable to read AMBIENT chunk");
+            ASSIMP_LOG_ERROR("3DS: Unable to read AMBIENT chunk");
             pc->r = pc->g = pc->b = 0.0f;
         }}
         break;
@@ -1159,7 +1159,7 @@ void Discreet3DSImporter::ParseMaterialChunk()
         ParseColorChunk(pc);
         if (is_qnan(pc->r)) {
             // color chunk is invalid. Simply ignore it
-            DefaultLogger::get()->error("3DS: Unable to read EMISSIVE chunk");
+            ASSIMP_LOG_ERROR("3DS: Unable to read EMISSIVE chunk");
             pc->r = pc->g = pc->b = 0.0f;
         }}
         break;
@@ -1293,7 +1293,7 @@ void Discreet3DSImporter::ParseTextureChunk(D3DS::Texture* pcOut)
         pcOut->mScaleU = stream->GetF4();
         if (0.0f == pcOut->mScaleU)
         {
-            DefaultLogger::get()->warn("Texture coordinate scaling in the x direction is zero. Assuming 1.");
+            ASSIMP_LOG_WARN("Texture coordinate scaling in the x direction is zero. Assuming 1.");
             pcOut->mScaleU = 1.0f;
         }
         break;
@@ -1302,7 +1302,7 @@ void Discreet3DSImporter::ParseTextureChunk(D3DS::Texture* pcOut)
         pcOut->mScaleV = stream->GetF4();
         if (0.0f == pcOut->mScaleV)
         {
-            DefaultLogger::get()->warn("Texture coordinate scaling in the y direction is zero. Assuming 1.");
+            ASSIMP_LOG_WARN("Texture coordinate scaling in the y direction is zero. Assuming 1.");
             pcOut->mScaleV = 1.0f;
         }
         break;
diff --git a/code/ACLoader.cpp b/code/ACLoader.cpp
index 3f8653d5d..7b8afbe9b 100644
--- a/code/ACLoader.cpp
+++ b/code/ACLoader.cpp
@@ -85,7 +85,7 @@ static const aiImporterDesc desc = {
 #define AI_AC_SKIP_TO_NEXT_TOKEN() \
     if (!SkipSpaces(&buffer)) \
     { \
-        DefaultLogger::get()->error("AC3D: Unexpected EOF/EOL"); \
+        ASSIMP_LOG_ERROR("AC3D: Unexpected EOF/EOL"); \
         continue; \
     }
 
@@ -101,7 +101,7 @@ static const aiImporterDesc desc = {
     { \
         if (IsLineEnd( *buffer )) \
         { \
-            DefaultLogger::get()->error("AC3D: Unexpected EOF/EOL in string"); \
+            ASSIMP_LOG_ERROR("AC3D: Unexpected EOF/EOL in string"); \
             out = "ERROR"; \
             break; \
         } \
@@ -120,7 +120,7 @@ static const aiImporterDesc desc = {
     { \
         if (strncmp(buffer,name,name_length) || !IsSpace(buffer[name_length])) \
         { \
-            DefaultLogger::get()->error("AC3D: Unexpexted token. " name " was expected."); \
+            ASSIMP_LOG_ERROR("AC3D: Unexpexted token. " name " was expected."); \
             continue; \
         } \
         buffer += name_length+1; \
@@ -217,7 +217,7 @@ void AC3DImporter::LoadObjectSection(std::vector<Object>& objects)
         light->mName.length = ::ai_snprintf(light->mName.data, MAXLEN, "ACLight_%i",static_cast<unsigned int>(mLights->size())-1);
         obj.name = std::string( light->mName.data );
 
-        DefaultLogger::get()->debug("AC3D: Light source encountered");
+        ASSIMP_LOG_DEBUG("AC3D: Light source encountered");
         obj.type = Object::Light;
     }
     else if (!ASSIMP_strincmp(buffer,"group",5))
@@ -307,12 +307,12 @@ void AC3DImporter::LoadObjectSection(std::vector<Object>& objects)
             {
                 if (!GetNextLine())
                 {
-                    DefaultLogger::get()->error("AC3D: Unexpected EOF: not all vertices have been parsed yet");
+                    ASSIMP_LOG_ERROR("AC3D: Unexpected EOF: not all vertices have been parsed yet");
                     break;
                 }
                 else if (!IsNumeric(*buffer))
                 {
-                    DefaultLogger::get()->error("AC3D: Unexpected token: not all vertices have been parsed yet");
+                    ASSIMP_LOG_ERROR("AC3D: Unexpected token: not all vertices have been parsed yet");
                     --buffer; // make sure the line is processed a second time
                     break;
                 }
@@ -338,8 +338,8 @@ void AC3DImporter::LoadObjectSection(std::vector<Object>& objects)
                     // example writes no surf chunks
                     if (!Q3DWorkAround)
                     {
-                        DefaultLogger::get()->warn("AC3D: SURF token was expected");
-                        DefaultLogger::get()->debug("Continuing with Quick3D Workaround enabled");
+                        ASSIMP_LOG_WARN("AC3D: SURF token was expected");
+                        ASSIMP_LOG_DEBUG("Continuing with Quick3D Workaround enabled");
                     }
                     --buffer; // make sure the line is processed a second time
                     // break; --- see fix notes above
@@ -384,7 +384,7 @@ void AC3DImporter::LoadObjectSection(std::vector<Object>& objects)
                         {
                             if(!GetNextLine())
                             {
-                                DefaultLogger::get()->error("AC3D: Unexpected EOF: surface references are incomplete");
+                                ASSIMP_LOG_ERROR("AC3D: Unexpected EOF: surface references are incomplete");
                                 break;
                             }
                             surf.entries.push_back(Surface::SurfaceEntry());
@@ -405,7 +405,7 @@ void AC3DImporter::LoadObjectSection(std::vector<Object>& objects)
             }
         }
     }
-    DefaultLogger::get()->error("AC3D: Unexpected EOF: \'kids\' line was expected");
+    ASSIMP_LOG_ERROR("AC3D: Unexpected EOF: \'kids\' line was expected");
 }
 
 // ------------------------------------------------------------------------------------------------
@@ -478,7 +478,7 @@ aiNode* AC3DImporter::ConvertObjectSection(Object& object,
                  therefore: if no surfaces are defined return point data only
              */
 
-            DefaultLogger::get()->info("AC3D: No surfaces defined in object definition, "
+            ASSIMP_LOG_INFO("AC3D: No surfaces defined in object definition, "
                 "a point list is returned");
 
             meshes.push_back(new aiMesh());
@@ -519,12 +519,12 @@ aiNode* AC3DImporter::ConvertObjectSection(Object& object,
                 unsigned int idx = (*it).mat;
                 if (idx >= needMat.size())
                 {
-                    DefaultLogger::get()->error("AC3D: material index is out of range");
+                    ASSIMP_LOG_ERROR("AC3D: material index is out of range");
                     idx = 0;
                 }
                 if ((*it).entries.empty())
                 {
-                    DefaultLogger::get()->warn("AC3D: surface her zero vertex references");
+                    ASSIMP_LOG_WARN("AC3D: surface her zero vertex references");
                 }
 
                 // validate all vertex indices to make sure we won't crash here
@@ -533,7 +533,7 @@ aiNode* AC3DImporter::ConvertObjectSection(Object& object,
                 {
                     if ((*it2).first >= object.vertices.size())
                     {
-                        DefaultLogger::get()->warn("AC3D: Invalid vertex reference");
+                        ASSIMP_LOG_WARN("AC3D: Invalid vertex reference");
                         (*it2).first = 0;
                     }
                 }
@@ -561,7 +561,7 @@ aiNode* AC3DImporter::ConvertObjectSection(Object& object,
 
                     if ((*it).flags & 0xf)
                     {
-                        DefaultLogger::get()->warn("AC3D: The type flag of a surface is unknown");
+                        ASSIMP_LOG_WARN("AC3D: The type flag of a surface is unknown");
                         (*it).flags &= ~(0xf);
                     }
 
@@ -712,7 +712,7 @@ aiNode* AC3DImporter::ConvertObjectSection(Object& object,
             if (object.subDiv)  {
                 if (configEvalSubdivision) {
                     std::unique_ptr<Subdivider> div(Subdivider::Create(Subdivider::CATMULL_CLARKE));
-                    DefaultLogger::get()->info("AC3D: Evaluating subdivision surface: "+object.name);
+                    ASSIMP_LOG_INFO("AC3D: Evaluating subdivision surface: "+object.name);
 
                     std::vector<aiMesh*> cpy(meshes.size()-oldm,NULL);
                     div->Subdivide(&meshes[oldm],cpy.size(),&cpy.front(),object.subDiv,true);
@@ -721,7 +721,7 @@ aiNode* AC3DImporter::ConvertObjectSection(Object& object,
                     // previous meshes are deleted vy Subdivide().
                 }
                 else {
-                    DefaultLogger::get()->info("AC3D: Letting the subdivision surface untouched due to my configuration: "
+                    ASSIMP_LOG_INFO("AC3D: Letting the subdivision surface untouched due to my configuration: "
                         +object.name);
                 }
             }
@@ -813,7 +813,7 @@ void AC3DImporter::InternReadFile( const std::string& pFile,
     unsigned int version = HexDigitToDecimal( buffer[4] );
     char msg[3];
     ASSIMP_itoa10(msg,3,version);
-    DefaultLogger::get()->info(std::string("AC3D file format version: ") + msg);
+    ASSIMP_LOG_INFO_F("AC3D file format version: ", msg);
 
     std::vector<Material> materials;
     materials.reserve(5);
@@ -857,7 +857,7 @@ void AC3DImporter::InternReadFile( const std::string& pFile,
     }
     if (materials.empty())
     {
-        DefaultLogger::get()->warn("AC3D: No material has been found");
+        ASSIMP_LOG_WARN("AC3D: No material has been found");
         materials.push_back(Material());
     }
 
diff --git a/code/ASELoader.cpp b/code/ASELoader.cpp
index 32b0eae2d..1808f25e2 100644
--- a/code/ASELoader.cpp
+++ b/code/ASELoader.cpp
@@ -200,7 +200,7 @@ void ASEImporter::InternReadFile( const std::string& pFile,
             ConvertMeshes(*i,avOutMeshes);
         }
         if (tookNormals)    {
-            DefaultLogger::get()->debug("ASE: Taking normals from the file. Use "
+            ASSIMP_LOG_DEBUG("ASE: Taking normals from the file. Use "
                 "the AI_CONFIG_IMPORT_ASE_RECONSTRUCT_NORMALS setting if you "
                 "experience problems");
         }
@@ -297,15 +297,15 @@ void ASEImporter::BuildAnimations(const std::vector<BaseNode*>& nodes)
 
         // TODO: Implement Bezier & TCB support
         if ((*i)->mAnim.mPositionType != ASE::Animation::TRACK) {
-            DefaultLogger::get()->warn("ASE: Position controller uses Bezier/TCB keys. "
+            ASSIMP_LOG_WARN("ASE: Position controller uses Bezier/TCB keys. "
                 "This is not supported.");
         }
         if ((*i)->mAnim.mRotationType != ASE::Animation::TRACK) {
-            DefaultLogger::get()->warn("ASE: Rotation controller uses Bezier/TCB keys. "
+            ASSIMP_LOG_WARN("ASE: Rotation controller uses Bezier/TCB keys. "
                 "This is not supported.");
         }
         if ((*i)->mAnim.mScalingType != ASE::Animation::TRACK)  {
-            DefaultLogger::get()->warn("ASE: Position controller uses Bezier/TCB keys. "
+            ASSIMP_LOG_WARN("ASE: Position controller uses Bezier/TCB keys. "
                 "This is not supported.");
         }
 
@@ -624,7 +624,7 @@ void ASEImporter::AddNodes (const std::vector<BaseNode*>& nodes,
             node->mNumChildren++;
 
             // What we did is so great, it is at least worth a debug message
-            DefaultLogger::get()->debug("ASE: Generating separate target node ("+snode->mName+")");
+            ASSIMP_LOG_DEBUG("ASE: Generating separate target node ("+snode->mName+")");
         }
     }
 
@@ -947,7 +947,7 @@ void ASEImporter::ConvertMeshes(ASE::Mesh& mesh, std::vector<aiMesh*>& avOutMesh
     // validate the material index of the mesh
     if (mesh.iMaterialIndex >= mParser->m_vMaterials.size())    {
         mesh.iMaterialIndex = (unsigned int)mParser->m_vMaterials.size()-1;
-        DefaultLogger::get()->warn("Material index is out of range");
+        ASSIMP_LOG_WARN("Material index is out of range");
     }
 
     // If the material the mesh is assigned to is consisting of submeshes, split it
@@ -957,11 +957,11 @@ void ASEImporter::ConvertMeshes(ASE::Mesh& mesh, std::vector<aiMesh*>& avOutMesh
 
         std::vector<unsigned int>* aiSplit = new std::vector<unsigned int>[vSubMaterials.size()];
 
-        // build a list of all faces per submaterial
+        // build a list of all faces per sub-material
         for (unsigned int i = 0; i < mesh.mFaces.size();++i)    {
             // check range
             if (mesh.mFaces[i].iMaterial >= vSubMaterials.size()) {
-                DefaultLogger::get()->warn("Submaterial index is out of range");
+                ASSIMP_LOG_WARN("Submaterial index is out of range");
 
                 // use the last material instead
                 aiSplit[vSubMaterials.size()-1].push_back(i);
diff --git a/code/ASEParser.cpp b/code/ASEParser.cpp
index b953f8d96..298c6fe61 100644
--- a/code/ASEParser.cpp
+++ b/code/ASEParser.cpp
@@ -151,7 +151,7 @@ void Parser::LogWarning(const char* szWarn)
 #endif
 
     // output the warning to the logger ...
-    DefaultLogger::get()->warn(szTemp);
+    ASSIMP_LOG_WARN(szTemp);
 }
 
 // ------------------------------------------------------------------------------------------------
@@ -167,7 +167,7 @@ void Parser::LogInfo(const char* szWarn)
 #endif
 
     // output the information to the logger ...
-    DefaultLogger::get()->info(szTemp);
+    ASSIMP_LOG_INFO(szTemp);
 }
 
 // ------------------------------------------------------------------------------------------------
@@ -758,7 +758,7 @@ void Parser::ParseLV3MapBlock(Texture& map)
                     SkipToNextToken();
                 if (temp != "Bitmap" && temp != "Normal Bump")
                 {
-                    DefaultLogger::get()->warn("ASE: Skipping unknown map type: " + temp);
+                    ASSIMP_LOG_WARN_F("ASE: Skipping unknown map type: ", temp);
                     parsePath = false;
                 }
                 continue;
@@ -773,7 +773,7 @@ void Parser::ParseLV3MapBlock(Texture& map)
                 {
                     // Files with 'None' as map name are produced by
                     // an Maja to ASE exporter which name I forgot ..
-                    DefaultLogger::get()->warn("ASE: Skipping invalid map entry");
+                    ASSIMP_LOG_WARN("ASE: Skipping invalid map entry");
                     map.mMapName = "";
                 }
 
@@ -1072,7 +1072,7 @@ void Parser::ParseLV2AnimationBlock(ASE::BaseNode& mesh)
                         ( mesh.mType != BaseNode::Light  || ((ASE::Light&)mesh).mLightType   != ASE::Light::TARGET))
                     {
 
-                        DefaultLogger::get()->error("ASE: Found target animation channel "
+                        ASSIMP_LOG_ERROR("ASE: Found target animation channel "
                             "but the node is neither a camera nor a spot light");
                         anim = NULL;
                     }
@@ -1098,7 +1098,7 @@ void Parser::ParseLV2AnimationBlock(ASE::BaseNode& mesh)
                 if (!anim || anim == &mesh.mTargetAnim)
                 {
                     // Target animation channels may have no rotation channels
-                    DefaultLogger::get()->error("ASE: Ignoring scaling channel in target animation");
+                    ASSIMP_LOG_ERROR("ASE: Ignoring scaling channel in target animation");
                     SkipSection();
                 }
                 else ParseLV3ScaleAnimationBlock(*anim);
@@ -1112,7 +1112,7 @@ void Parser::ParseLV2AnimationBlock(ASE::BaseNode& mesh)
                 if (!anim || anim == &mesh.mTargetAnim)
                 {
                     // Target animation channels may have no rotation channels
-                    DefaultLogger::get()->error("ASE: Ignoring rotation channel in target animation");
+                    ASSIMP_LOG_ERROR("ASE: Ignoring rotation channel in target animation");
                     SkipSection();
                 }
                 else ParseLV3RotAnimationBlock(*anim);
@@ -1295,12 +1295,14 @@ void Parser::ParseLV2NodeTransformBlock(ASE::BaseNode& mesh)
                     {
                         mode = 2;
                     }
-                    else DefaultLogger::get()->error("ASE: Ignoring target transform, "
-                        "this is no spot light or target camera");
+                    else {
+                        ASSIMP_LOG_ERROR("ASE: Ignoring target transform, "
+                            "this is no spot light or target camera");
+                    }
                 }
                 else
                 {
-                    DefaultLogger::get()->error("ASE: Unknown node transformation: " + temp);
+                    ASSIMP_LOG_ERROR("ASE: Unknown node transformation: " + temp);
                     // mode = 0
                 }
                 continue;
@@ -1916,7 +1918,7 @@ void Parser::ParseLV3MeshNormalListBlock(ASE::Mesh& sMesh)
                 else if (index == face.mIndices[2])
                     index = 2;
                 else    {
-                    DefaultLogger::get()->error("ASE: Invalid vertex index in MESH_VERTEXNORMAL section");
+                    ASSIMP_LOG_ERROR("ASE: Invalid vertex index in MESH_VERTEXNORMAL section");
                     continue;
                 }
                 // We'll renormalize later
@@ -1928,7 +1930,7 @@ void Parser::ParseLV3MeshNormalListBlock(ASE::Mesh& sMesh)
                 ParseLV4MeshFloatTriple(&vNormal.x,faceIdx);
 
                 if (faceIdx >= sMesh.mFaces.size()) {
-                    DefaultLogger::get()->error("ASE: Invalid vertex index in MESH_FACENORMAL section");
+                    ASSIMP_LOG_ERROR("ASE: Invalid vertex index in MESH_FACENORMAL section");
                     continue;
                 }
 
diff --git a/code/B3DImporter.cpp b/code/B3DImporter.cpp
index e4572f8eb..ce8bd5159 100644
--- a/code/B3DImporter.cpp
+++ b/code/B3DImporter.cpp
@@ -614,7 +614,7 @@ void B3DImporter::ReadBB3D( aiScene *scene ){
         if (!DefaultLogger::isNullLogger()) {
             char dmp[128];
             ai_snprintf(dmp, 128, "B3D file format version: %i",version);
-            DefaultLogger::get()->info(dmp);
+            ASSIMP_LOG_INFO(dmp);
         }
 
         while( ChunkSize() ){
diff --git a/code/BaseImporter.cpp b/code/BaseImporter.cpp
index 4782e9e2d..fa9f70603 100644
--- a/code/BaseImporter.cpp
+++ b/code/BaseImporter.cpp
@@ -64,23 +64,24 @@ using namespace Assimp;
 // ------------------------------------------------------------------------------------------------
 // Constructor to be privately used by Importer
 BaseImporter::BaseImporter()
-: m_progress()
-{
+: m_progress() {
     // nothing to do here
 }
 
 // ------------------------------------------------------------------------------------------------
 // Destructor, private as well
-BaseImporter::~BaseImporter()
-{
+BaseImporter::~BaseImporter() {
     // nothing to do here
 }
 
 // ------------------------------------------------------------------------------------------------
 // Imports the given file and returns the imported data.
-aiScene* BaseImporter::ReadFile(const Importer* pImp, const std::string& pFile, IOSystem* pIOHandler)
-{
+aiScene* BaseImporter::ReadFile(const Importer* pImp, const std::string& pFile, IOSystem* pIOHandler) {
     m_progress = pImp->GetProgressHandler();
+    if (nullptr == m_progress) {
+        return nullptr;
+    }
+
     ai_assert(m_progress);
 
     // Gather configuration properties for this run
@@ -100,8 +101,8 @@ aiScene* BaseImporter::ReadFile(const Importer* pImp, const std::string& pFile,
     } catch( const std::exception& err )    {
         // extract error description
         m_ErrorText = err.what();
-        DefaultLogger::get()->error(m_ErrorText);
-        return NULL;
+        ASSIMP_LOG_ERROR(m_ErrorText);
+        return nullptr;
     }
 
     // return what we gathered from the import.
@@ -195,7 +196,7 @@ void BaseImporter::GetExtensionList(std::set<std::string>& extensions) {
             // We got a match, either we don't care where it is, or it happens to
             // be in the beginning of the file / line
             if (!tokensSol || r == buffer || r[-1] == '\r' || r[-1] == '\n') {
-                DefaultLogger::get()->debug(std::string("Found positive match for header keyword: ") + tokens[i]);
+                ASSIMP_LOG_DEBUG_F( "Found positive match for header keyword: ", tokens[i] );
                 return true;
             }
         }
@@ -322,7 +323,7 @@ void BaseImporter::ConvertToUTF8(std::vector<char>& data)
 
     // UTF 8 with BOM
     if((uint8_t)data[0] == 0xEF && (uint8_t)data[1] == 0xBB && (uint8_t)data[2] == 0xBF) {
-        DefaultLogger::get()->debug("Found UTF-8 BOM ...");
+        ASSIMP_LOG_DEBUG("Found UTF-8 BOM ...");
 
         std::copy(data.begin()+3,data.end(),data.begin());
         data.resize(data.size()-3);
@@ -341,7 +342,7 @@ void BaseImporter::ConvertToUTF8(std::vector<char>& data)
 
     // UTF 32 LE with BOM
     if(*((uint32_t*)&data.front()) == 0x0000FFFE) {
-        DefaultLogger::get()->debug("Found UTF-32 BOM ...");
+        ASSIMP_LOG_DEBUG("Found UTF-32 BOM ...");
 
         std::vector<char> output;
         int *ptr = (int*)&data[ 0 ];
@@ -361,7 +362,7 @@ void BaseImporter::ConvertToUTF8(std::vector<char>& data)
 
     // UTF 16 LE with BOM
     if(*((uint16_t*)&data.front()) == 0xFEFF) {
-        DefaultLogger::get()->debug("Found UTF-16 BOM ...");
+        ASSIMP_LOG_DEBUG("Found UTF-16 BOM ...");
 
         std::vector<unsigned char> output;
         utf8::utf16to8(data.begin(), data.end(), back_inserter(output));
@@ -386,16 +387,14 @@ void BaseImporter::ConvertUTF8toISO8859_1(std::string& data)
                 data[j] = ((unsigned char) data[++i] + 0x40);
             } else {
                 std::stringstream stream;
-
                 stream << "UTF8 code " << std::hex << data[i] << data[i + 1] << " can not be converted into ISA-8859-1.";
-
-                DefaultLogger::get()->error(stream.str());
+                ASSIMP_LOG_ERROR( stream.str() );
 
                 data[j++] = data[i++];
                 data[j] = data[i];
             }
         } else {
-            DefaultLogger::get()->error("UTF8 code but only one character remaining");
+            ASSIMP_LOG_ERROR("UTF8 code but only one character remaining");
 
             data[j] = data[i];
         }
@@ -411,7 +410,7 @@ void BaseImporter::TextFileToBuffer(IOStream* stream,
     std::vector<char>& data,
     TextFileMode mode)
 {
-    ai_assert(NULL != stream);
+    ai_assert(nullptr != stream);
 
     const size_t fileSize = stream->FileSize();
     if (mode == FORBID_EMPTY) {
@@ -472,14 +471,14 @@ struct Assimp::BatchData {
     , pImporter( nullptr )
     , next_id(0xffff)
     , validate( validate ) {
-        ai_assert( NULL != pIO );
+        ai_assert( nullptr != pIO );
         
         pImporter = new Importer();
         pImporter->SetIOHandler( pIO );
     }
 
     ~BatchData() {
-        pImporter->SetIOHandler( NULL ); /* get pointer back into our possession */
+        pImporter->SetIOHandler( nullptr ); /* get pointer back into our possession */
         delete pImporter;
     }
 
@@ -505,9 +504,8 @@ struct Assimp::BatchData {
 typedef std::list<LoadRequest>::iterator LoadReqIt;
 
 // ------------------------------------------------------------------------------------------------
-BatchLoader::BatchLoader(IOSystem* pIO, bool validate )
-{
-    ai_assert(NULL != pIO);
+BatchLoader::BatchLoader(IOSystem* pIO, bool validate ) {
+    ai_assert(nullptr != pIO);
 
     m_data = new BatchData( pIO, validate );
 }
@@ -573,7 +571,7 @@ aiScene* BatchLoader::GetImport( unsigned int which )
             return sc;
         }
     }
-    return NULL;
+    return nullptr;
 }
 
 // ------------------------------------------------------------------------------------------------
@@ -596,13 +594,13 @@ void BatchLoader::LoadAll()
 
         if (!DefaultLogger::isNullLogger())
         {
-            DefaultLogger::get()->info("%%% BEGIN EXTERNAL FILE %%%");
-            DefaultLogger::get()->info("File: " + (*it).file);
+            ASSIMP_LOG_INFO("%%% BEGIN EXTERNAL FILE %%%");
+            ASSIMP_LOG_INFO("File: ", (*it).file);
         }
         m_data->pImporter->ReadFile((*it).file,pp);
         (*it).scene = m_data->pImporter->GetOrphanedScene();
         (*it).loaded = true;
 
-        DefaultLogger::get()->info("%%% END EXTERNAL FILE %%%");
+        ASSIMP_LOG_INFO("%%% END EXTERNAL FILE %%%");
     }
 }
diff --git a/code/BaseProcess.cpp b/code/BaseProcess.cpp
index 8508f59e4..ba968a819 100644
--- a/code/BaseProcess.cpp
+++ b/code/BaseProcess.cpp
@@ -85,7 +85,7 @@ void BaseProcess::ExecuteOnScene( Importer* pImp)
 
         // extract error description
         pImp->Pimpl()->mErrorString = err.what();
-        DefaultLogger::get()->error(pImp->Pimpl()->mErrorString);
+        ASSIMP_LOG_ERROR(pImp->Pimpl()->mErrorString);
 
         // and kill the partially imported data
         delete pImp->Pimpl()->mScene;
diff --git a/code/BlenderDNA.cpp b/code/BlenderDNA.cpp
index 1d88f8fa6..0bca902c6 100644
--- a/code/BlenderDNA.cpp
+++ b/code/BlenderDNA.cpp
@@ -210,8 +210,7 @@ void DNAParser::Parse ()
         s.size = offset;
     }
 
-    DefaultLogger::get()->debug((format(),"BlenderDNA: Got ",dna.structures.size(),
-        " structures with totally ",fields," fields"));
+    ASSIMP_LOG_DEBUG( "BlenderDNA: Got ", dna.structures.size()," structures with totally ",fields," fields");
 
 #ifdef ASSIMP_BUILD_BLENDER_DEBUG
     dna.DumpToFile();
@@ -233,7 +232,7 @@ void DNA :: DumpToFile()
 
     std::ofstream f("dna.txt");
     if (f.fail()) {
-        DefaultLogger::get()->error("Could not dump dna to dna.txt");
+        ASSIMP_LOG_ERROR("Could not dump dna to dna.txt");
         return;
     }
     f << "Field format: type name offset size" << "\n";
@@ -248,7 +247,7 @@ void DNA :: DumpToFile()
     }
     f << std::flush;
 
-    DefaultLogger::get()->info("BlenderDNA: Dumped dna to dna.txt");
+    ASSIMP_LOG_INFO("BlenderDNA: Dumped dna to dna.txt");
 }
 #endif
 
@@ -367,7 +366,7 @@ void SectionParser :: Next()
     }
 
 #ifdef ASSIMP_BUILD_BLENDER_DEBUG
-    DefaultLogger::get()->debug(current.id);
+    ASSIMP_LOG_DEBUG(current.id);
 #endif
 }
 
diff --git a/code/BlenderDNA.h b/code/BlenderDNA.h
index 3a2455275..4a1e83b64 100644
--- a/code/BlenderDNA.h
+++ b/code/BlenderDNA.h
@@ -381,7 +381,7 @@ template <>  struct Structure :: _defaultInitializer<ErrorPolicy_Warn> {
 
     template <typename T>
     void operator ()(T& out, const char* reason = "<add reason>") {
-        DefaultLogger::get()->warn(reason);
+        ASSIMP_LOG_WARN(reason);
 
         // ... and let the show go on
         _defaultInitializer<0 /*ErrorPolicy_Igno*/>()(out);
diff --git a/code/BlenderDNA.inl b/code/BlenderDNA.inl
index 163798a40..1f345b631 100644
--- a/code/BlenderDNA.inl
+++ b/code/BlenderDNA.inl
@@ -468,9 +468,7 @@ template <> bool Structure :: ResolvePointer<std::shared_ptr,ElemBase>(std::shar
         // this might happen if DNA::RegisterConverters hasn't been called so far
         // or if the target type is not contained in `our` DNA.
         out.reset();
-        DefaultLogger::get()->warn((Formatter::format(),
-            "Failed to find a converter for the `",s.name,"` structure"
-            ));
+        ASSIMP_LOG_WARN( "Failed to find a converter for the `",s.name,"` structure" );
         return false;
     }
 
diff --git a/code/BlenderLoader.cpp b/code/BlenderLoader.cpp
index d4d6473c5..71880e3ac 100644
--- a/code/BlenderLoader.cpp
+++ b/code/BlenderLoader.cpp
@@ -327,12 +327,12 @@ void BlenderImporter::ExtractScene(Scene& out, const FileDatabase& file)
     ss.Convert(out,file);
 
 #ifndef ASSIMP_BUILD_BLENDER_NO_STATS
-    DefaultLogger::get()->info((format(),
+    ASSIMP_LOG_INFO_F(
         "(Stats) Fields read: " ,file.stats().fields_read,
         ", pointers resolved: " ,file.stats().pointers_resolved,
         ", cache hits: "        ,file.stats().cache_hits,
         ", cached objects: "    ,file.stats().cached_objects
-    ));
+    );
 #endif
 }
 
diff --git a/code/BlenderModifier.h b/code/BlenderModifier.h
index cd34659c9..1b0976b1e 100644
--- a/code/BlenderModifier.h
+++ b/code/BlenderModifier.h
@@ -86,7 +86,7 @@ public:
         const Scene& /*in*/,
         const Object& /*orig_object*/
     ) {
-        DefaultLogger::get()->warn((Formatter::format("This modifier is not supported, skipping: "),orig_modifier.dna_type));
+        ASSIMP_LOG_INFO_F("This modifier is not supported, skipping: "),orig_modifier.dna_type);
         return;
     }
 };
diff --git a/code/COBLoader.cpp b/code/COBLoader.cpp
index 222088cbd..ae65f8f93 100644
--- a/code/COBLoader.cpp
+++ b/code/COBLoader.cpp
@@ -150,7 +150,7 @@ void COBImporter::InternReadFile( const std::string& pFile,
         ThrowException("Could not found magic id: `Caligari`");
     }
 
-    DefaultLogger::get()->info("File format tag: "+std::string(head+9,6));
+    ASSIMP_LOG_INFO_F("File format tag: ",std::string(head+9,6));
     if (head[16]!='L') {
         ThrowException("File is big-endian, which is not supported");
     }
@@ -303,7 +303,7 @@ aiNode* COBImporter::BuildNodes(const Node& root,const Scene& scin,aiScene* fill
                     }
                     std::unique_ptr<const Material> defmat;
                     if(!min) {
-                        DefaultLogger::get()->debug(format()<<"Could not resolve material index "
+                        ASSIMP_LOG_DEBUG(format()<<"Could not resolve material index "
                             <<reflist.first<<" - creating default material for this slot");
 
                         defmat.reset(min=new Material());
@@ -475,7 +475,7 @@ void COBImporter::UnsupportedChunk_Ascii(LineSplitter& splitter, const ChunkInfo
 
     // we can recover if the chunk size was specified.
     if(nfo.size != static_cast<unsigned int>(-1)) {
-        DefaultLogger::get()->error(error);
+        ASSIMP_LOG_ERROR(error);
 
         // (HACK) - our current position in the stream is the beginning of the
         // head line of the next chunk. That's fine, but the caller is going
@@ -935,7 +935,7 @@ void COBImporter::UnsupportedChunk_Binary( StreamReaderLE& reader, const ChunkIn
 
     // we can recover if the chunk size was specified.
     if(nfo.size != static_cast<unsigned int>(-1)) {
-        DefaultLogger::get()->error(error);
+        ASSIMP_LOG_ERROR(error);
         reader.IncPtr(nfo.size);
     }
     else ThrowException(error);
diff --git a/code/ColladaLoader.cpp b/code/ColladaLoader.cpp
index 4bb5f4521..a26df1898 100644
--- a/code/ColladaLoader.cpp
+++ b/code/ColladaLoader.cpp
@@ -294,7 +294,7 @@ void ColladaLoader::ResolveNodeInstances( const ColladaParser& pParser, const Co
             nd = FindNode(pParser.mRootNode, nodeInst.mNode);
         }
         if (!nd)
-            DefaultLogger::get()->error("Collada: Unable to resolve reference to instanced node " + nodeInst.mNode);
+            ASSIMP_LOG_ERROR_F("Collada: Unable to resolve reference to instanced node ", nodeInst.mNode);
 
         else {
             //  attach this node to the list of children
@@ -311,7 +311,7 @@ void ColladaLoader::ApplyVertexToEffectSemanticMapping(Collada::Sampler& sampler
     std::map<std::string, Collada::InputSemanticMapEntry>::const_iterator it = table.mMap.find(sampler.mUVChannel);
     if (it != table.mMap.end()) {
         if (it->second.mType != Collada::IT_Texcoord)
-            DefaultLogger::get()->error("Collada: Unexpected effect input mapping");
+            ASSIMP_LOG_ERROR("Collada: Unexpected effect input mapping");
 
         sampler.mUVId = it->second.mSet;
     }
@@ -327,7 +327,7 @@ void ColladaLoader::BuildLightsForNode( const ColladaParser& pParser, const Coll
         ColladaParser::LightLibrary::const_iterator srcLightIt = pParser.mLightLibrary.find( lid.mLight);
         if( srcLightIt == pParser.mLightLibrary.end())
         {
-            DefaultLogger::get()->warn("Collada: Unable to find light for ID \"" + lid.mLight + "\". Skipping.");
+            ASSIMP_LOG_WARN_F("Collada: Unable to find light for ID \"" , lid.mLight , "\". Skipping.");
             continue;
         }
         const Collada::Light* srcLight = &srcLightIt->second;
@@ -395,14 +395,14 @@ void ColladaLoader::BuildCamerasForNode( const ColladaParser& pParser, const Col
         ColladaParser::CameraLibrary::const_iterator srcCameraIt = pParser.mCameraLibrary.find( cid.mCamera);
         if( srcCameraIt == pParser.mCameraLibrary.end())
         {
-            DefaultLogger::get()->warn("Collada: Unable to find camera for ID \"" + cid.mCamera + "\". Skipping.");
+            ASSIMP_LOG_WARN_F("Collada: Unable to find camera for ID \"" , cid.mCamera , "\". Skipping.");
             continue;
         }
         const Collada::Camera* srcCamera = &srcCameraIt->second;
 
         // orthographic cameras not yet supported in Assimp
         if (srcCamera->mOrtho) {
-            DefaultLogger::get()->warn("Collada: Orthographic cameras are not supported.");
+            ASSIMP_LOG_WARN("Collada: Orthographic cameras are not supported.");
         }
 
         // now fill our ai data structure
@@ -472,7 +472,7 @@ void ColladaLoader::BuildMeshesForNode( const ColladaParser& pParser, const Coll
 
             if( !srcMesh)
             {
-                DefaultLogger::get()->warn( format() << "Collada: Unable to find geometry for ID \"" << mid.mMeshOrController << "\". Skipping." );
+                ASSIMP_LOG_WARN( "Collada: Unable to find geometry for ID \"", mid.mMeshOrController, "\". Skipping." );
                 continue;
             }
         } else
@@ -501,7 +501,8 @@ void ColladaLoader::BuildMeshesForNode( const ColladaParser& pParser, const Coll
             }
             else
             {
-                DefaultLogger::get()->warn( format() << "Collada: No material specified for subgroup <" << submesh.mMaterial << "> in geometry <" << mid.mMeshOrController << ">." );
+                ASSIMP_LOG_WARN_F( "Collada: No material specified for subgroup <", submesh.mMaterial, "> in geometry <",
+                    mid.mMeshOrController, ">." );
                 if( !mid.mMaterials.empty() )
                     meshMaterial = mid.mMaterials.begin()->second.mMatName;
             }
@@ -874,7 +875,7 @@ aiMesh* ColladaLoader::CreateMesh( const ColladaParser& pParser, const Collada::
             if( bnode)
                 bone->mName.Set( FindNameForNode( bnode));
             else
-                DefaultLogger::get()->warn( format() << "ColladaLoader::CreateMesh(): could not find corresponding node for joint \"" << bone->mName.data << "\"." );
+                ASSIMP_LOG_WARN( "ColladaLoader::CreateMesh(): could not find corresponding node for joint \"", bone->mName.data, "\"." );
 
             // and insert bone
             dstMesh->mBones[boneCount++] = bone;
@@ -1175,7 +1176,7 @@ void ColladaLoader::CreateAnimation( aiScene* pScene, const ColladaParser& pPars
                 else if( subElement == "Z")
                     entry.mSubElement = 2;
                 else
-                    DefaultLogger::get()->warn( format() << "Unknown anim subelement <" << subElement << ">. Ignoring" );
+                    ASSIMP_LOG_WARN( "Unknown anim subelement <", subElement, ">. Ignoring" );
             } else
             {
                 // no subelement following, transformId is remaining string
@@ -1406,7 +1407,7 @@ void ColladaLoader::CreateAnimation( aiScene* pScene, const ColladaParser& pPars
               anims.push_back( dstAnim);
         } else
         {
-          DefaultLogger::get()->warn( "Collada loader: found empty animation channel, ignored. Please check your exporter.");
+            ASSIMP_LOG_WARN( "Collada loader: found empty animation channel, ignored. Please check your exporter.");
         }
 
         if( !entries.empty() && entries.front().mTimeAccessor->mCount > 0 )
@@ -1561,7 +1562,7 @@ void ColladaLoader::AddTexture ( aiMaterial& mat, const ColladaParser& pParser,
             }
         }
         if (-1 == map) {
-            DefaultLogger::get()->warn("Collada: unable to determine UV channel for texture");
+            ASSIMP_LOG_WARN("Collada: unable to determine UV channel for texture");
             map = 0;
         }
     }
@@ -1598,7 +1599,7 @@ void ColladaLoader::FillMaterials( const ColladaParser& pParser, aiScene* /*pSce
                 break;
 
             default:
-                DefaultLogger::get()->warn("Collada: Unrecognized shading mode, using gouraud shading");
+                ASSIMP_LOG_WARN("Collada: Unrecognized shading mode, using gouraud shading");
                 shadeMode = aiShadingMode_Gouraud;
                 break;
             }
@@ -1752,11 +1753,7 @@ aiString ColladaLoader::FindFilenameForEffectTexture( const ColladaParser& pPars
     ColladaParser::ImageLibrary::const_iterator imIt = pParser.mImageLibrary.find( name);
     if( imIt == pParser.mImageLibrary.end())
     {
-        //missing texture should not stop the conversion
-        //throw DeadlyImportError( format() <<
-        //    "Collada: Unable to resolve effect texture entry \"" << pName << "\", ended up at ID \"" << name << "\"." );
-
-        DefaultLogger::get()->warn("Collada: Unable to resolve effect texture entry \"" + pName + "\", ended up at ID \"" + name + "\".");
+        ASSIMP_LOG_WARN_F("Collada: Unable to resolve effect texture entry \"", pName, "\", ended up at ID \"", name, "\".");
 
         //set default texture file name
         result.Set(name + ".jpg");
@@ -1775,7 +1772,7 @@ aiString ColladaLoader::FindFilenameForEffectTexture( const ColladaParser& pPars
 
         // setup format hint
         if (imIt->second.mEmbeddedFormat.length() > 3) {
-            DefaultLogger::get()->warn("Collada: texture format hint is too long, truncating to 3 characters");
+            ASSIMP_LOG_WARN("Collada: texture format hint is too long, truncating to 3 characters");
         }
         strncpy(tex->achFormatHint,imIt->second.mEmbeddedFormat.c_str(),3);
 
diff --git a/code/ColladaParser.cpp b/code/ColladaParser.cpp
index 31fbabe0e..20d6a39d5 100644
--- a/code/ColladaParser.cpp
+++ b/code/ColladaParser.cpp
@@ -152,22 +152,22 @@ void ColladaParser::ReadContents()
 
                     if (!::strncmp(version,"1.5",3)) {
                         mFormat =  FV_1_5_n;
-                        DefaultLogger::get()->debug("Collada schema version is 1.5.n");
+                        ASSIMP_LOG_DEBUG("Collada schema version is 1.5.n");
                     }
                     else if (!::strncmp(version,"1.4",3)) {
                         mFormat =  FV_1_4_n;
-                        DefaultLogger::get()->debug("Collada schema version is 1.4.n");
+                        ASSIMP_LOG_DEBUG("Collada schema version is 1.4.n");
                     }
                     else if (!::strncmp(version,"1.3",3)) {
                         mFormat =  FV_1_3_n;
-                        DefaultLogger::get()->debug("Collada schema version is 1.3.n");
+                        ASSIMP_LOG_DEBUG("Collada schema version is 1.3.n");
                     }
                 }
 
                 ReadStructure();
             } else
             {
-                DefaultLogger::get()->debug( format() << "Ignoring global element <" << mReader->getNodeName() << ">." );
+                ASSIMP_LOG_DEBUG_F( "Ignoring global element <", mReader->getNodeName(), ">." );
                 SkipElement();
             }
         } else
@@ -984,13 +984,13 @@ void ColladaParser::ReadImage( Collada::Image& pImage)
                     // they're not skipped.
                     int attrib = TestAttribute("array_index");
                     if (attrib != -1 && mReader->getAttributeValueAsInt(attrib) > 0) {
-                        DefaultLogger::get()->warn("Collada: Ignoring texture array index");
+                        ASSIMP_LOG_WARN("Collada: Ignoring texture array index");
                         continue;
                     }
 
                     attrib = TestAttribute("mip_index");
                     if (attrib != -1 && mReader->getAttributeValueAsInt(attrib) > 0) {
-                        DefaultLogger::get()->warn("Collada: Ignoring MIP map layer");
+                        ASSIMP_LOG_WARN("Collada: Ignoring MIP map layer");
                         continue;
                     }
 
@@ -1011,7 +1011,7 @@ void ColladaParser::ReadImage( Collada::Image& pImage)
                     // embedded image. get format
                     const int attrib = TestAttribute("format");
                     if (-1 == attrib)
-                        DefaultLogger::get()->warn("Collada: Unknown image file format");
+                        ASSIMP_LOG_WARN("Collada: Unknown image file format");
                     else pImage.mEmbeddedFormat = mReader->getAttributeValue(attrib);
 
                     const char* data = GetTextContent();
@@ -1590,7 +1590,7 @@ void ColladaParser::ReadSamplerProperties( Sampler& out )
                     out.mOp = aiTextureOp_Multiply;
 
                 else  {
-                    DefaultLogger::get()->warn("Collada: Unsupported MAYA texture blend mode");
+                    ASSIMP_LOG_WARN("Collada: Unsupported MAYA texture blend mode");
                 }
                 TestClosing( "blend_mode");
             }
@@ -2541,7 +2541,7 @@ void ColladaParser::ExtractDataObjectFromChannel( const InputChannel& pInput, si
             if( pInput.mIndex == 0)
                 pMesh->mPositions.push_back( aiVector3D( obj[0], obj[1], obj[2]));
             else
-                DefaultLogger::get()->error("Collada: just one vertex position stream supported");
+                ASSIMP_LOG_ERROR("Collada: just one vertex position stream supported");
             break;
         case IT_Normal:
             // pad to current vertex count if necessary
@@ -2552,7 +2552,7 @@ void ColladaParser::ExtractDataObjectFromChannel( const InputChannel& pInput, si
             if( pInput.mIndex == 0)
                 pMesh->mNormals.push_back( aiVector3D( obj[0], obj[1], obj[2]));
             else
-                DefaultLogger::get()->error("Collada: just one vertex normal stream supported");
+                ASSIMP_LOG_ERROR("Collada: just one vertex normal stream supported");
             break;
         case IT_Tangent:
             // pad to current vertex count if necessary
@@ -2563,7 +2563,7 @@ void ColladaParser::ExtractDataObjectFromChannel( const InputChannel& pInput, si
             if( pInput.mIndex == 0)
                 pMesh->mTangents.push_back( aiVector3D( obj[0], obj[1], obj[2]));
             else
-                DefaultLogger::get()->error("Collada: just one vertex tangent stream supported");
+                ASSIMP_LOG_ERROR("Collada: just one vertex tangent stream supported");
             break;
         case IT_Bitangent:
             // pad to current vertex count if necessary
@@ -2574,7 +2574,7 @@ void ColladaParser::ExtractDataObjectFromChannel( const InputChannel& pInput, si
             if( pInput.mIndex == 0)
                 pMesh->mBitangents.push_back( aiVector3D( obj[0], obj[1], obj[2]));
             else
-                DefaultLogger::get()->error("Collada: just one vertex bitangent stream supported");
+                ASSIMP_LOG_ERROR("Collada: just one vertex bitangent stream supported");
             break;
         case IT_Texcoord:
             // up to 4 texture coord sets are fine, ignore the others
@@ -2590,7 +2590,7 @@ void ColladaParser::ExtractDataObjectFromChannel( const InputChannel& pInput, si
                     pMesh->mNumUVComponents[pInput.mIndex]=3;
             }   else
             {
-                DefaultLogger::get()->error("Collada: too many texture coordinate sets. Skipping.");
+                ASSIMP_LOG_ERROR("Collada: too many texture coordinate sets. Skipping.");
             }
             break;
         case IT_Color:
@@ -2610,7 +2610,7 @@ void ColladaParser::ExtractDataObjectFromChannel( const InputChannel& pInput, si
                 pMesh->mColors[pInput.mIndex].push_back(result);
             } else
             {
-                DefaultLogger::get()->error("Collada: too many vertex color sets. Skipping.");
+                ASSIMP_LOG_ERROR("Collada: too many vertex color sets. Skipping.");
             }
 
             break;
@@ -2739,7 +2739,7 @@ void ColladaParser::ReadSceneNode( Node* pNode)
                 {
                     const char* s = mReader->getAttributeValue(attrId);
                     if (s[0] != '#')
-                        DefaultLogger::get()->error("Collada: Unresolved reference format of camera");
+                        ASSIMP_LOG_ERROR("Collada: Unresolved reference format of camera");
                     else
                         pNode->mPrimaryCamera = s+1;
                 }
@@ -2752,7 +2752,7 @@ void ColladaParser::ReadSceneNode( Node* pNode)
                 {
                     const char* s = mReader->getAttributeValue(attrID);
                     if (s[0] != '#')
-                        DefaultLogger::get()->error("Collada: Unresolved reference format of node");
+                        ASSIMP_LOG_ERROR("Collada: Unresolved reference format of node");
                     else
                     {
                         pNode->mNodeInstances.push_back(NodeInstance());
diff --git a/code/D3MFImporter.cpp b/code/D3MFImporter.cpp
index 2732c73c4..0a3a140f3 100644
--- a/code/D3MFImporter.cpp
+++ b/code/D3MFImporter.cpp
@@ -396,7 +396,7 @@ private:
                 return false;
             }
         }
-        DefaultLogger::get()->error("unexpected EOF, expected closing <" + closeTag + "> tag");
+        ASSIMP_LOG_ERROR("unexpected EOF, expected closing <" + closeTag + "> tag");
 
         return false;
     }
diff --git a/code/D3MFOpcPackage.cpp b/code/D3MFOpcPackage.cpp
index 3bf545813..8161a31e4 100644
--- a/code/D3MFOpcPackage.cpp
+++ b/code/D3MFOpcPackage.cpp
@@ -465,7 +465,7 @@ D3MFOpcPackage::D3MFOpcPackage(IOSystem* pIOHandler, const std::string& rFile)
                 }
             }
 
-            DefaultLogger::get()->debug(rootFile);
+            ASSIMP_LOG_DEBUG(rootFile);
 
             mRootStream = mZipArchive->Open(rootFile.c_str());
             ai_assert( mRootStream != nullptr );
diff --git a/code/DXFLoader.cpp b/code/DXFLoader.cpp
index c8aee18dd..6c42d0fc2 100644
--- a/code/DXFLoader.cpp
+++ b/code/DXFLoader.cpp
@@ -212,7 +212,7 @@ void DXFImporter::InternReadFile( const std::string& pFile,
         ++reader;
     }
     if (!eof) {
-        DefaultLogger::get()->warn("DXF: EOF reached, but did not encounter DXF EOF marker");
+        ASSIMP_LOG_WARN("DXF: EOF reached, but did not encounter DXF EOF marker");
     }
 
     ConvertMeshes(pScene,output);
@@ -229,7 +229,7 @@ void DXFImporter::InternReadFile( const std::string& pFile,
 void DXFImporter::ConvertMeshes(aiScene* pScene, DXF::FileData& output)
 {
     // the process of resolving all the INSERT statements can grow the
-    // polycount excessively, so log the original number.
+    // poly-count excessively, so log the original number.
     // XXX Option to import blocks as separate nodes?
     if (!DefaultLogger::isNullLogger()) {
 
@@ -241,16 +241,14 @@ void DXFImporter::ConvertMeshes(aiScene* pScene, DXF::FileData& output)
             }
         }
 
-        DefaultLogger::get()->debug((Formatter::format("DXF: Unexpanded polycount is "),
-            icount,", vertex count is ",vcount
-        ));
+        ASSIMP_LOG_DEBUG("DXF: Unexpanded polycount is ", icount, ", vertex count is ", vcount);
     }
 
     if (! output.blocks.size()  ) {
         throw DeadlyImportError("DXF: no data blocks loaded");
     }
 
-    DXF::Block* entities = 0;
+    DXF::Block* entities( nullptr );
 
     // index blocks by name
     DXF::BlockMap blocks_by_name;
@@ -375,9 +373,7 @@ void DXFImporter::ExpandBlockReferences(DXF::Block& bl,const DXF::BlockMap& bloc
         // first check if the referenced blocks exists ...
         const DXF::BlockMap::const_iterator it = blocks_by_name.find(insert.name);
         if (it == blocks_by_name.end()) {
-            DefaultLogger::get()->error((Formatter::format("DXF: Failed to resolve block reference: "),
-                insert.name,"; skipping"
-            ));
+            ASSIMP_LOG_ERROR("DXF: Failed to resolve block reference: ", insert.name,"; skipping" );
             continue;
         }
 
diff --git a/code/Importer.cpp b/code/Importer.cpp
index 6f9b47562..1b3ccf2a1 100644
--- a/code/Importer.cpp
+++ b/code/Importer.cpp
@@ -368,11 +368,11 @@ bool Importer::IsDefaultProgressHandler() const
 bool _ValidateFlags(unsigned int pFlags)
 {
     if (pFlags & aiProcess_GenSmoothNormals && pFlags & aiProcess_GenNormals)   {
-        DefaultLogger::get()->error("#aiProcess_GenSmoothNormals and #aiProcess_GenNormals are incompatible");
+        ASSIMP_LOG_ERROR("#aiProcess_GenSmoothNormals and #aiProcess_GenNormals are incompatible");
         return false;
     }
     if (pFlags & aiProcess_OptimizeGraph && pFlags & aiProcess_PreTransformVertices)    {
-        DefaultLogger::get()->error("#aiProcess_OptimizeGraph and #aiProcess_PreTransformVertices are incompatible");
+        ASSIMP_LOG_ERROR("#aiProcess_OptimizeGraph and #aiProcess_PreTransformVertices are incompatible");
         return false;
     }
     return true;
@@ -594,7 +594,7 @@ const aiScene* Importer::ReadFile( const char* _pFile, unsigned int pFlags)
         if( !pimpl->mIOHandler->Exists( pFile)) {
 
             pimpl->mErrorString = "Unable to open file \"" + pFile + "\".";
-            DefaultLogger::get()->error(pimpl->mErrorString);
+            ASSIMP_LOG_ERROR(pimpl->mErrorString);
             return NULL;
         }
 
@@ -628,7 +628,7 @@ const aiScene* Importer::ReadFile( const char* _pFile, unsigned int pFlags)
             // Put a proper error message if no suitable importer was found
             if( !imp)   {
                 pimpl->mErrorString = "No suitable reader found for the file format of file \"" + pFile + "\".";
-                DefaultLogger::get()->error(pimpl->mErrorString);
+                ASSIMP_LOG_ERROR(pimpl->mErrorString);
                 return NULL;
             }
         }
@@ -716,7 +716,7 @@ const aiScene* Importer::ReadFile( const char* _pFile, unsigned int pFlags)
         pimpl->mErrorString = std::string("std::exception: ") + e.what();
 #endif
 
-        DefaultLogger::get()->error(pimpl->mErrorString);
+        ASSIMP_LOG_ERROR(pimpl->mErrorString);
         delete pimpl->mScene; pimpl->mScene = NULL;
     }
 #endif // ! ASSIMP_CATCH_GLOBAL_EXCEPTIONS
@@ -762,7 +762,7 @@ const aiScene* Importer::ApplyPostProcessing(unsigned int pFlags)
     if (pimpl->bExtraVerbose)
     {
 #ifdef ASSIMP_BUILD_NO_VALIDATEDS_PROCESS
-        DefaultLogger::get()->error("Verbose Import is not available due to build settings");
+        ASSIMP_LOG_ERROR("Verbose Import is not available due to build settings");
 #endif  // no validation
         pFlags |= aiProcess_ValidateDataStructure;
     }
@@ -800,18 +800,19 @@ const aiScene* Importer::ApplyPostProcessing(unsigned int pFlags)
 
         // If the extra verbose mode is active, execute the ValidateDataStructureStep again - after each step
         if (pimpl->bExtraVerbose)   {
-            DefaultLogger::get()->debug("Verbose Import: revalidating data structures");
+            DefaultLogger::get()->debug("Verbose Import: re-validating data structures");
 
             ValidateDSProcess ds;
             ds.ExecuteOnScene (this);
             if( !pimpl->mScene) {
-                DefaultLogger::get()->error("Verbose Import: failed to revalidate data structures");
+                ASSIMP_LOG_ERROR("Verbose Import: failed to re-validate data structures");
                 break;
             }
         }
 #endif // ! DEBUG
     }
-    pimpl->mProgressHandler->UpdatePostProcess( static_cast<int>(pimpl->mPostProcessingSteps.size()), static_cast<int>(pimpl->mPostProcessingSteps.size()) );
+    pimpl->mProgressHandler->UpdatePostProcess( static_cast<int>(pimpl->mPostProcessingSteps.size()), 
+        static_cast<int>(pimpl->mPostProcessingSteps.size()) );
 
     // update private scene flags
     if( pimpl->mScene )
@@ -858,7 +859,7 @@ const aiScene* Importer::ApplyCustomizedPostProcessing( BaseProcess *rootProcess
     if ( pimpl->bExtraVerbose )
     {
 #ifdef ASSIMP_BUILD_NO_VALIDATEDS_PROCESS
-        DefaultLogger::get()->error( "Verbose Import is not available due to build settings" );
+        ASSIMP_LOG_ERROR( "Verbose Import is not available due to build settings" );
 #endif  // no validation
     }
 #else
@@ -886,7 +887,7 @@ const aiScene* Importer::ApplyCustomizedPostProcessing( BaseProcess *rootProcess
         ValidateDSProcess ds;
         ds.ExecuteOnScene( this );
         if ( !pimpl->mScene ) {
-            DefaultLogger::get()->error( "Verbose Import: failed to revalidate data structures" );
+            ASSIMP_LOG_ERROR( "Verbose Import: failed to revalidate data structures" );
         }
     }
 
diff --git a/code/SceneCombiner.cpp b/code/SceneCombiner.cpp
index 589291131..2b6b1e19a 100644
--- a/code/SceneCombiner.cpp
+++ b/code/SceneCombiner.cpp
@@ -622,8 +622,8 @@ void SceneCombiner::MergeScenes(aiScene** _dest, aiScene* master, std::vector<At
                 }
             }
             if (!(*it).resolved) {
-                DefaultLogger::get()->error(std::string("SceneCombiner: Failed to resolve attachment ")
-                    + (*it).node->mName.data + " " + (*it).attachToNode->mName.data);
+                ASSIMP_LOG_ERROR_F( "SceneCombiner: Failed to resolve attachment ", (*it).node->mName.data,
+                    " ", (*it).attachToNode->mName.data );
             }
         }
     }
diff --git a/code/UnrealLoader.cpp b/code/UnrealLoader.cpp
index 5990ce1c5..64bfbb9e0 100644
--- a/code/UnrealLoader.cpp
+++ b/code/UnrealLoader.cpp
@@ -153,9 +153,9 @@ void UnrealImporter::InternReadFile( const std::string& pFile,
     a_path  = extension+"_a.3d";
     uc_path = extension+".uc";
 
-    DefaultLogger::get()->debug("UNREAL: data file is " + d_path);
-    DefaultLogger::get()->debug("UNREAL: aniv file is " + a_path);
-    DefaultLogger::get()->debug("UNREAL: uc file is "   + uc_path);
+    ASSIMP_LOG_DEBUG_F( "UNREAL: data file is ", d_path);
+    ASSIMP_LOG_DEBUG_F("UNREAL: aniv file is ", a_path);
+    ASSIMP_LOG_DEBUG_F("UNREAL: uc file is ", uc_path);
 
     // and open the files ... we can't live without them
     std::unique_ptr<IOStream> p(pIOHandler->Open(d_path));
@@ -179,7 +179,7 @@ void UnrealImporter::InternReadFile( const std::string& pFile,
 
             tri.mVertex[i] = d_reader.GetI2();
             if (tri.mVertex[i] >= numTris)  {
-                DefaultLogger::get()->warn("UNREAL: vertex index out of range");
+                ASSIMP_LOG_WARN("UNREAL: vertex index out of range");
                 tri.mVertex[i] = 0;
             }
         }
@@ -324,7 +324,7 @@ void UnrealImporter::InternReadFile( const std::string& pFile,
         }
     }
     else    {
-        DefaultLogger::get()->error("Unable to open .uc file");
+        ASSIMP_LOG_ERROR("Unable to open .uc file");
     }
 
     std::vector<Unreal::TempMat> materials;
diff --git a/include/assimp/BlobIOSystem.h b/include/assimp/BlobIOSystem.h
index 3c1691d5b..a0ed7209f 100644
--- a/include/assimp/BlobIOSystem.h
+++ b/include/assimp/BlobIOSystem.h
@@ -251,7 +251,7 @@ public:
             }
         }
         if (!master) {
-            DefaultLogger::get()->error("BlobIOSystem: no data written or master file was not closed properly.");
+            ASSIMP_LOG_ERROR("BlobIOSystem: no data written or master file was not closed properly.");
             return NULL;
         }