diff --git a/.clang-format b/.clang-format
index eba6d586f..c8b8ab856 100644
--- a/.clang-format
+++ b/.clang-format
@@ -71,7 +71,7 @@ IncludeCategories:
     Priority:        3
 # IncludeIsMainRegex: '(Test)?$'
 IndentCaseLabels: true
-# IndentPPDirectives: None
+IndentPPDirectives: AfterHash
 IndentWidth:     4
 # IndentWrappedFunctionNames: false
 # JavaScriptQuotes: Leave
@@ -108,7 +108,7 @@ IndentWidth:     4
 # SpacesInParentheses: false
 # SpacesInSquareBrackets: false
 TabWidth:        4
-UseTab:          Always
+UseTab:          Never
 ---
 ### C++ specific config ###
 Language:        Cpp
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 08a1f3010..b98d1f78a 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -441,10 +441,6 @@ ELSE(HUNTER_ENABLED)
     DESTINATION "${ASSIMP_LIB_INSTALL_DIR}/cmake/assimp-${ASSIMP_VERSION_MAJOR}.${ASSIMP_VERSION_MINOR}" COMPONENT ${LIBASSIMP-DEV_COMPONENT})
 ENDIF(HUNTER_ENABLED)
 
-if (ASSIMP_BUILD_SAMPLES OR ASSIMP_BUILD_SAMPLES)
-  FIND_PACKAGE(DirectX)
-endif(ASSIMP_BUILD_SAMPLES OR ASSIMP_BUILD_SAMPLES)
-
 IF( BUILD_DOCS )
   ADD_SUBDIRECTORY(doc)
 ENDIF( BUILD_DOCS )
diff --git a/code/Common/BaseImporter.cpp b/code/Common/BaseImporter.cpp
index 660a6a965..8d7b029ba 100644
--- a/code/Common/BaseImporter.cpp
+++ b/code/Common/BaseImporter.cpp
@@ -191,7 +191,7 @@ void BaseImporter::GetExtensionList(std::set<std::string>& extensions) {
     }
 
     std::unique_ptr<IOStream> pStream (pIOHandler->Open(pFile));
-    if (pStream.get() ) {
+    if (pStream) {
         // read 200 characters from the file
         std::unique_ptr<char[]> _buffer (new char[searchBytes+1 /* for the '\0' */]);
         char *buffer( _buffer.get() );
@@ -283,7 +283,6 @@ std::string BaseImporter::GetExtension( const std::string& file ) {
         return "";
     }
 
-
     // thanks to Andy Maloney for the hint
     std::string ret = file.substr( pos + 1 );
     std::transform( ret.begin(), ret.end(), ret.begin(), ToLower<char>);
@@ -309,7 +308,7 @@ std::string BaseImporter::GetExtension( const std::string& file ) {
     };
     magic = reinterpret_cast<const char*>(_magic);
     std::unique_ptr<IOStream> pStream (pIOHandler->Open(pFile));
-    if (pStream.get() ) {
+    if (pStream) {
 
         // skip to offset
         pStream->Seek(offset,aiOrigin_SET);
@@ -603,7 +602,7 @@ unsigned int BatchLoader::AddLoadRequest(const std::string& file,
     }
 
     // no, we don't have it. So add it to the queue ...
-    m_data->requests.push_back(LoadRequest(file,steps,map, m_data->next_id));
+    m_data->requests.emplace_back(file, steps, map, m_data->next_id);
     return m_data->next_id++;
 }
 
diff --git a/code/Common/Importer.cpp b/code/Common/Importer.cpp
index 5601298f1..a59ec9812 100644
--- a/code/Common/Importer.cpp
+++ b/code/Common/Importer.cpp
@@ -1071,7 +1071,7 @@ ai_real Importer::GetPropertyFloat(const char* szName, ai_real iErrorReturn /*=
 
 // ------------------------------------------------------------------------------------------------
 // Get a configuration property
-const std::string Importer::GetPropertyString(const char* szName, const std::string& iErrorReturn /*= ""*/) const {
+std::string Importer::GetPropertyString(const char* szName, const std::string& iErrorReturn /*= ""*/) const {
     ai_assert(nullptr != pimpl);
     
     return GetGenericProperty<std::string>(pimpl->mStringProperties,szName,iErrorReturn);
@@ -1079,7 +1079,7 @@ const std::string Importer::GetPropertyString(const char* szName, const std::str
 
 // ------------------------------------------------------------------------------------------------
 // Get a configuration property
-const aiMatrix4x4 Importer::GetPropertyMatrix(const char* szName, const aiMatrix4x4& iErrorReturn /*= aiMatrix4x4()*/) const {
+aiMatrix4x4 Importer::GetPropertyMatrix(const char* szName, const aiMatrix4x4& iErrorReturn /*= aiMatrix4x4()*/) const {
     ai_assert(nullptr != pimpl);
     
     return GetGenericProperty<aiMatrix4x4>(pimpl->mMatrixProperties,szName,iErrorReturn);
@@ -1110,10 +1110,9 @@ void Importer::GetMemoryRequirements(aiMemoryInfo& in) const {
     aiScene* mScene = pimpl->mScene;
 
     // return if we have no scene loaded
-    if (!pimpl->mScene)
+    if (!mScene)
         return;
 
-
     in.total = sizeof(aiScene);
 
     // add all meshes
@@ -1202,5 +1201,6 @@ void Importer::GetMemoryRequirements(aiMemoryInfo& in) const {
             in.materials += pc->mProperties[a]->mDataLength;
         }
     }
+
     in.total += in.materials;
 }
diff --git a/code/Common/ZipArchiveIOSystem.cpp b/code/Common/ZipArchiveIOSystem.cpp
index e83d3e50d..8d00da912 100644
--- a/code/Common/ZipArchiveIOSystem.cpp
+++ b/code/Common/ZipArchiveIOSystem.cpp
@@ -343,8 +343,6 @@ namespace Assimp {
     }
 
     ZipArchiveIOSystem::Implement::~Implement() {
-        m_ArchiveMap.clear();
-
         if (m_ZipFileHandle != nullptr) {
             unzClose(m_ZipFileHandle);
             m_ZipFileHandle = nullptr;
diff --git a/code/Obj/ObjFileData.h b/code/Obj/ObjFileData.h
index 985a49a42..298d1e1b7 100644
--- a/code/Obj/ObjFileData.h
+++ b/code/Obj/ObjFileData.h
@@ -110,10 +110,7 @@ struct Object {
     std::vector<unsigned int> m_Meshes;
 
     //! \brief  Default constructor
-    Object() 
-    : m_strObjName("") {
-        // empty
-    }
+    Object() = default;
 
     //! \brief  Destructor
     ~Object() {
@@ -191,16 +188,12 @@ struct Material {
     ,   illumination_model (1)
     ,   ior     ( ai_real( 1.0 ) )
     ,   transparent( ai_real( 1.0), ai_real (1.0), ai_real(1.0)) {
-        // empty
-        for (size_t i = 0; i < TextureTypeCount; ++i) {
-            clamp[ i ] = false;
-        }
+
+	    std::fill_n(clamp, static_cast<unsigned int>(TextureTypeCount), false);
     }
 
     // Destructor
-    ~Material() {
-        // empty
-    }
+    ~Material() = default;
 };
 
 // ------------------------------------------------------------------------------------------------
diff --git a/code/Obj/ObjFileParser.cpp b/code/Obj/ObjFileParser.cpp
index 48129c02c..7ba2216ae 100644
--- a/code/Obj/ObjFileParser.cpp
+++ b/code/Obj/ObjFileParser.cpp
@@ -53,6 +53,8 @@ OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 #include <assimp/material.h>
 #include <assimp/Importer.hpp>
 #include <cstdlib>
+#include <memory>
+#include <utility>
 
 namespace Assimp {
 
@@ -71,16 +73,16 @@ ObjFileParser::ObjFileParser()
 
 ObjFileParser::ObjFileParser( IOStreamBuffer<char> &streamBuffer, const std::string &modelName,
                               IOSystem *io, ProgressHandler* progress,
-                              const std::string &originalObjFileName) :
+                              std::string originalObjFileName) :
     m_DataIt(),
     m_DataItEnd(),
     m_pModel(nullptr),
     m_uiLine(0),
-    m_pIO( io ),
+    m_pIO(io),
     m_progress(progress),
-    m_originalObjFileName(originalObjFileName)
+    m_originalObjFileName(std::move(originalObjFileName))
 {
-    std::fill_n(m_buffer,Buffersize,0);
+    std::fill_n(m_buffer, Buffersize,0);
 
     // Create the model instance to store all the data
     m_pModel.reset(new ObjFile::Model());
@@ -96,7 +98,8 @@ ObjFileParser::ObjFileParser( IOStreamBuffer<char> &streamBuffer, const std::str
     parseFile( streamBuffer );
 }
 
-ObjFileParser::~ObjFileParser() {
+ObjFileParser::~ObjFileParser()
+{
 }
 
 void ObjFileParser::setBuffer( std::vector<char> &buffer ) {
@@ -128,7 +131,7 @@ void ObjFileParser::parseFile( IOStreamBuffer<char> &streamBuffer ) {
             processed = static_cast<unsigned int>(filePos);
             lastFilePos = filePos;
             progressCounter++;
-            m_progress->UpdateFileRead( processed, progressTotal );
+            m_progress->UpdateFileRead(processed, progressTotal);
         }
 
         // parse line
diff --git a/code/Obj/ObjFileParser.h b/code/Obj/ObjFileParser.h
index 124527413..f0f5a2dc1 100644
--- a/code/Obj/ObjFileParser.h
+++ b/code/Obj/ObjFileParser.h
@@ -78,7 +78,7 @@ public:
     /// @brief  The default constructor.
     ObjFileParser();
     /// @brief  Constructor with data array.
-    ObjFileParser( IOStreamBuffer<char> &streamBuffer, const std::string &modelName, IOSystem* io, ProgressHandler* progress, const std::string &originalObjFileName);
+    ObjFileParser(IOStreamBuffer<char> &streamBuffer, const std::string &modelName, IOSystem* io, ProgressHandler* progress, std::string originalObjFileName);
     /// @brief  Destructor
     ~ObjFileParser();
     /// @brief  If you want to load in-core data.
diff --git a/code/PostProcessing/TextureTransform.cpp b/code/PostProcessing/TextureTransform.cpp
index cebbd8042..bf60e2970 100644
--- a/code/PostProcessing/TextureTransform.cpp
+++ b/code/PostProcessing/TextureTransform.cpp
@@ -92,9 +92,8 @@ void TextureTransformStep::PreProcessUVTransform(STransformVecInfo& info)
      *  are applied is - as always - scaling, rotation, translation.
      */
 
-    char szTemp[512];
-    int rounded = 0;
-
+	int rounded;
+	char szTemp[512];
 
     /* Optimize the rotation angle. That's slightly difficult as
      * we have an inprecise floating-point number (when comparing
@@ -185,7 +184,6 @@ void TextureTransformStep::PreProcessUVTransform(STransformVecInfo& info)
             info.mTranslation.y = out;
         }
     }
-    return;
 }
 
 // ------------------------------------------------------------------------------------------------
@@ -428,7 +426,7 @@ void TextureTransformStep::Execute( aiScene* pScene)
         // at the end of the list
         bool ref[AI_MAX_NUMBER_OF_TEXTURECOORDS];
         for (unsigned int n = 0; n < AI_MAX_NUMBER_OF_TEXTURECOORDS;++n)
-            ref[n] = (!mesh->mTextureCoords[n] ? true : false);
+            ref[n] = !mesh->mTextureCoords[n];
 
         for (it = trafo.begin();it != trafo.end(); ++it)
             ref[(*it).uvIndex] = true;
diff --git a/include/assimp/Importer.hpp b/include/assimp/Importer.hpp
index 7ec4f519c..df52471a9 100644
--- a/include/assimp/Importer.hpp
+++ b/include/assimp/Importer.hpp
@@ -285,7 +285,7 @@ public:
      *  The return value remains valid until the property is modified.
      * @see GetPropertyInteger()
      */
-    const std::string GetPropertyString(const char* szName,
+    std::string GetPropertyString(const char* szName,
         const std::string& sErrorReturn = "") const;
 
     // -------------------------------------------------------------------
@@ -294,7 +294,7 @@ public:
      *  The return value remains valid until the property is modified.
      * @see GetPropertyInteger()
      */
-    const aiMatrix4x4 GetPropertyMatrix(const char* szName,
+    aiMatrix4x4 GetPropertyMatrix(const char* szName,
         const aiMatrix4x4& sErrorReturn = aiMatrix4x4()) const;
 
     // -------------------------------------------------------------------
diff --git a/samples/SimpleTexturedOpenGL/CMakeLists.txt b/samples/SimpleTexturedOpenGL/CMakeLists.txt
index 40138c49b..941e18cea 100644
--- a/samples/SimpleTexturedOpenGL/CMakeLists.txt
+++ b/samples/SimpleTexturedOpenGL/CMakeLists.txt
@@ -35,7 +35,7 @@ ADD_EXECUTABLE( assimp_simpletexturedogl WIN32
 
 SET_PROPERTY(TARGET assimp_simpletexturedogl PROPERTY DEBUG_POSTFIX ${CMAKE_DEBUG_POSTFIX})
 
-TARGET_LINK_LIBRARIES( assimp_simpletexturedogl assimp ${OPENGL_LIBRARIES} ${GLUT_LIBRARIES} DevIL.lib )
+TARGET_LINK_LIBRARIES( assimp_simpletexturedogl assimp ${OPENGL_LIBRARIES} ${GLUT_LIBRARIES} )
 
 SET_TARGET_PROPERTIES( assimp_simpletexturedogl PROPERTIES
   OUTPUT_NAME assimp_simpletexturedogl
diff --git a/samples/SimpleTexturedOpenGL/SimpleTexturedOpenGL/src/model_loading.cpp b/samples/SimpleTexturedOpenGL/SimpleTexturedOpenGL/src/model_loading.cpp
index 8d25aaaed..8c2a08b2e 100644
--- a/samples/SimpleTexturedOpenGL/SimpleTexturedOpenGL/src/model_loading.cpp
+++ b/samples/SimpleTexturedOpenGL/SimpleTexturedOpenGL/src/model_loading.cpp
@@ -21,6 +21,8 @@
 #define STB_IMAGE_IMPLEMENTATION
 #include "contrib/stb_image/stb_image.h"
 
+#include <locale>
+#include <codecvt>
 #include <fstream>
 
 //to map image filenames to textureIds
@@ -75,6 +77,36 @@ GLuint*		textureIds;							// pointer to texture Array
 // Create an instance of the Importer class
 Assimp::Importer importer;
 
+// Used to convert between multibyte and unicode strings.
+class UTFConverter {
+	using UTFConverterImpl = std::wstring_convert<std::codecvt_utf8<wchar_t>, wchar_t>;
+public:
+	UTFConverter(const char* s) :
+		s_(s),
+		ws_(impl_.from_bytes(s)) {
+	}
+	UTFConverter(const std::string& s) :
+		s_(s),
+		ws_(impl_.from_bytes(s)) {
+	}
+	UTFConverter(const std::wstring& s) :
+		s_(impl_.to_bytes(s)),
+		ws_(s) {
+	}
+	inline const std::string& str() const {
+		return s_;
+	}
+	inline const wchar_t* c_wstr() const {
+		return ws_.c_str();
+	}
+private:
+	static UTFConverterImpl impl_;
+	std::string s_;
+	std::wstring ws_;
+};
+
+typename UTFConverter::UTFConverterImpl UTFConverter::impl_;
+
 void createAILogger()
 {
     // Change this line to normal if you not want to analyse the import process
@@ -120,7 +152,7 @@ bool Import3DFromFile( const std::string& pFile)
 	}
 	else
 	{
-		MessageBox(NULL, ("Couldn't open file: " + pFile).c_str() , "ERROR", MB_OK | MB_ICONEXCLAMATION);
+		MessageBox(NULL, UTFConverter("Couldn't open file: " + pFile).c_wstr() , TEXT("ERROR"), MB_OK | MB_ICONEXCLAMATION);
 		logInfo( importer.GetErrorString());
 		return false;
 	}
@@ -170,8 +202,21 @@ std::string getBasePath(const std::string& path)
 	return (std::string::npos == pos) ? "" : path.substr(0, pos + 1);
 }
 
+void freeTextureIds()
+{
+	textureIdMap.clear(); //no need to delete pointers in it manually here. (Pointers point to textureIds deleted in next step)
+
+	if (textureIds)
+	{
+		delete[] textureIds;
+		textureIds = NULL;
+	}
+}
+
 int LoadGLTextures(const aiScene* scene)
 {
+	freeTextureIds();
+
 	//ILboolean success;
 
 	/* Before calling ilInit() version should be checked. */
@@ -205,7 +250,7 @@ int LoadGLTextures(const aiScene* scene)
 		}
 	}
 
-	int numTextures = textureIdMap.size();
+	const size_t numTextures = textureIdMap.size();
 
 
 	/* array with DevIL image IDs */
@@ -217,13 +262,13 @@ int LoadGLTextures(const aiScene* scene)
 
 	/* create and fill array with GL texture ids */
 	textureIds = new GLuint[numTextures];
-	glGenTextures(numTextures, textureIds); /* Texture name generation */
+	glGenTextures(static_cast<GLsizei>(numTextures), textureIds); /* Texture name generation */
 
 	/* get iterator */
 	std::map<std::string, GLuint*>::iterator itr = textureIdMap.begin();
 
 	std::string basepath = getBasePath(modelpath);
-	for (int i=0; i<numTextures; i++)
+	for (size_t i=0; i<numTextures; i++)
 	{
 
 		//save IL image ID
@@ -268,7 +313,7 @@ int LoadGLTextures(const aiScene* scene)
 		else
 		{
 			/* Error occurred */
-			MessageBox(NULL, ("Couldn't load Image: " + fileloc).c_str() , "ERROR", MB_OK | MB_ICONEXCLAMATION);
+			MessageBox(NULL, UTFConverter("Couldn't load Image: " + fileloc).c_wstr(), TEXT("ERROR"), MB_OK | MB_ICONEXCLAMATION);
 		}
 	}
     // Because we have already copied image data into texture data  we can release memory used by image.
@@ -534,31 +579,34 @@ void KillGLWindow()			// Properly Kill The Window
 	{
 		if (!wglMakeCurrent(NULL, NULL))	// Are We Able To Release The DC And RC Contexts?
 		{
-			MessageBox(NULL, "Release Of DC And RC Failed.", "SHUTDOWN ERROR", MB_OK | MB_ICONINFORMATION);
+			MessageBox(NULL, TEXT("Release Of DC And RC Failed."), TEXT("SHUTDOWN ERROR"), MB_OK | MB_ICONINFORMATION);
 		}
 
 		if (!wglDeleteContext(hRC))			// Are We Able To Delete The RC?
 		{
-			MessageBox(NULL, "Release Rendering Context Failed.", "SHUTDOWN ERROR", MB_OK | MB_ICONINFORMATION);
+			MessageBox(NULL, TEXT("Release Rendering Context Failed."), TEXT("SHUTDOWN ERROR"), MB_OK | MB_ICONINFORMATION);
 		}
 		hRC = NULL;
 	}
 
-	if (hDC && !ReleaseDC(hWnd, hDC))	// Are We able to Release The DC?
+	if (hDC)
 	{
-		MessageBox(NULL, "Release Device Context Failed.", "SHUTDOWN ERROR", MB_OK | MB_ICONINFORMATION);
-		hDC=NULL;
+		if (!ReleaseDC(hWnd, hDC)) // Are We able to Release The DC?
+			MessageBox(NULL, TEXT("Release Device Context Failed."), TEXT("SHUTDOWN ERROR"), MB_OK | MB_ICONINFORMATION);
+		hDC = NULL;
 	}
 
-	if (hWnd && !DestroyWindow(hWnd))	// Are We Able To Destroy The Window
+	if (hWnd)
 	{
-		MessageBox(NULL, "Could Not Release hWnd.", "SHUTDOWN ERROR", MB_OK | MB_ICONINFORMATION);
+		if (!DestroyWindow(hWnd)) // Are We Able To Destroy The Window
+			MessageBox(NULL, TEXT("Could Not Release hWnd."), TEXT("SHUTDOWN ERROR"), MB_OK | MB_ICONINFORMATION);
 		hWnd = NULL;
-	}
+	} 
 
-	if (!UnregisterClass("OpenGL", hInstance))	// Are We Able To Unregister Class
+	if (hInstance)
 	{
-		MessageBox(NULL, "Could Not Unregister Class.", "SHUTDOWN ERROR", MB_OK | MB_ICONINFORMATION);
+		if (!UnregisterClass(TEXT("OpenGL"), hInstance)) // Are We Able To Unregister Class
+			MessageBox(NULL, TEXT("Could Not Unregister Class."), TEXT("SHUTDOWN ERROR"), MB_OK | MB_ICONINFORMATION);
 		hInstance = NULL;
 	}
 }
@@ -566,7 +614,7 @@ void KillGLWindow()			// Properly Kill The Window
 GLboolean abortGLInit(const char* abortMessage)
 {
 	KillGLWindow();									// Reset Display
-	MessageBox(NULL, abortMessage, "ERROR", MB_OK|MB_ICONEXCLAMATION);
+	MessageBox(NULL, UTFConverter(abortMessage).c_wstr(), TEXT("ERROR"), MB_OK|MB_ICONEXCLAMATION);
 	return FALSE;									// quit and return False
 }
 
@@ -594,11 +642,11 @@ BOOL CreateGLWindow(const char* title, int width, int height, int bits, bool ful
 	wc.hCursor		= LoadCursor(NULL, IDC_ARROW);	// Load the default arrow
 	wc.hbrBackground= NULL;							// No Background required for OpenGL
 	wc.lpszMenuName	= NULL;							// No Menu
-	wc.lpszClassName= "OpenGL";						// Class Name
+	wc.lpszClassName= TEXT("OpenGL");		        // Class Name
 
 	if (!RegisterClass(&wc))
 	{
-		MessageBox(NULL, "Failed to register the window class", "ERROR", MB_OK | MB_ICONEXCLAMATION);
+		MessageBox(NULL, TEXT("Failed to register the window class"), TEXT("ERROR"), MB_OK | MB_ICONEXCLAMATION);
 		return FALSE;		//exit and return false
 	}
 
@@ -616,14 +664,14 @@ BOOL CreateGLWindow(const char* title, int width, int height, int bits, bool ful
 		if (ChangeDisplaySettings(&dmScreenSettings, CDS_FULLSCREEN)!=DISP_CHANGE_SUCCESSFUL)
 		{
 			// If The Mode Fails, Offer Two Options.  Quit Or Run In A Window.
-			if (MessageBox(NULL,"The Requested Fullscreen Mode Is Not Supported By\nYour Video Card. Use Windowed Mode Instead?","NeHe GL",MB_YESNO|MB_ICONEXCLAMATION)==IDYES)
+			if (MessageBox(NULL,TEXT("The Requested Fullscreen Mode Is Not Supported By\nYour Video Card. Use Windowed Mode Instead?"),TEXT("NeHe GL"),MB_YESNO|MB_ICONEXCLAMATION)==IDYES)
 			{
 				fullscreen = FALSE;		// Select Windowed Mode (Fullscreen = FALSE)
 			}
 			else
 			{
 				//Popup Messagebox: Closing
-				MessageBox(NULL, "Program will close now.", "ERROR", MB_OK|MB_ICONSTOP);
+				MessageBox(NULL, TEXT("Program will close now."), TEXT("ERROR"), MB_OK|MB_ICONSTOP);
 				return FALSE; //exit, return false
 			}
 		}
@@ -644,8 +692,8 @@ BOOL CreateGLWindow(const char* title, int width, int height, int bits, bool ful
 	AdjustWindowRectEx(&WindowRect, dwStyle, FALSE, dwExStyle);		// Adjust Window To True Requestes Size
 
 	if (!(hWnd=CreateWindowEx(	dwExStyle,						// Extended Style For The Window
-								"OpenGL",						// Class Name
-								title,							// Window Title
+								TEXT("OpenGL"),						// Class Name
+								UTFConverter(title).c_wstr(),							// Window Title
 								WS_CLIPSIBLINGS |				// Required Window Style
 								WS_CLIPCHILDREN |				// Required Window Style
 								dwStyle,						// Selected WIndow Style
@@ -729,6 +777,16 @@ BOOL CreateGLWindow(const char* title, int width, int height, int bits, bool ful
 	return TRUE;
 }
 
+void cleanup()
+{
+	freeTextureIds();
+
+	destroyAILogger();
+
+	if (hWnd)
+		KillGLWindow();
+};
+
 LRESULT CALLBACK WndProc(HWND hWnd,				// Handles for this Window
 						 UINT uMsg,				// Message for this Window
 						 WPARAM wParam,			// additional message Info
@@ -807,20 +865,25 @@ int WINAPI WinMain( HINSTANCE hInstance,         // The instance
 	if (argv != NULL && argc > 1)
 	{
 		std::wstring modelpathW(argv[1]);
-		modelpath = std::string(modelpathW.begin(), modelpathW.end());
+		modelpath = UTFConverter(modelpathW).str();
 	}
 
-	if (!Import3DFromFile(modelpath)) return 0;
+	if (!Import3DFromFile(modelpath))
+	{
+		cleanup();
+		return 0;
+	}
 
 	logInfo("=============== Post Import ====================");
 
-	if (MessageBox(NULL, "Would You Like To Run In Fullscreen Mode?", "Start Fullscreen?", MB_YESNO|MB_ICONEXCLAMATION)==IDNO)
+	if (MessageBox(NULL, TEXT("Would You Like To Run In Fullscreen Mode?"), TEXT("Start Fullscreen?"), MB_YESNO|MB_ICONEXCLAMATION)==IDNO)
 	{
 		fullscreen=FALSE;
 	}
 
 	if (!CreateGLWindow(windowTitle, 640, 480, 16, fullscreen))
 	{
+		cleanup();
 		return 0;
 	}
 
@@ -861,6 +924,7 @@ int WINAPI WinMain( HINSTANCE hInstance,         // The instance
 				fullscreen=!fullscreen;
 				if (!CreateGLWindow(windowTitle, 640, 480, 16, fullscreen))
 				{
+					cleanup();
 					return 0;
 				}
 			}
@@ -868,18 +932,6 @@ int WINAPI WinMain( HINSTANCE hInstance,         // The instance
 	}
 
 	// *** cleanup ***
-
-	textureIdMap.clear(); //no need to delete pointers in it manually here. (Pointers point to textureIds deleted in next step)
-
-	if (textureIds)
-	{
-		delete[] textureIds;
-		textureIds = NULL;
-	}
-
-	// *** cleanup end ***
-
-	destroyAILogger();
-	KillGLWindow();
-	return (msg.wParam);
+	cleanup();
+	return static_cast<int>(msg.wParam);
 }