自学教程：C++ BX_UNUSED函数代码示例

	void setMouseLock(WindowHandle _handle, bool _lock)	{		BX_UNUSED(_handle, _lock);	}

extern "C" int fscanf(FILE* _stream, const char* _format, ...){	BX_UNUSED(_stream, _format);	return -1;}

extern "C" int fclose(FILE* _stream){	BX_UNUSED(_stream);	return -1;}

extern "C" int closedir (struct DIR* dirp){	BX_UNUSED(dirp);	return 0;}

extern "C" int vfprintf(FILE* _stream, const char* _format, va_list _argList){	BX_UNUSED(_stream, _format, _argList);	return -1;}

extern "C" float acosf(float _x){	BX_UNUSED(_x);	return 0.0f;}

extern "C" struct DIR* opendir(const char* dirname){	BX_UNUSED(dirname);	return NULL;}

extern "C" double ldexp(double _x, int _exp){	BX_UNUSED(_x, _exp);	return 0.0;}

extern "C" float log10f(float _x){	BX_UNUSED(_x);	return 0.0f;}

extern "C" char* strdup(const char* _src){	BX_UNUSED(_src);	return NULL;}

extern "C" long int strtol(const char* _str, char** _end, int _base){	BX_UNUSED(_str, _end, _base);	return -1;}

extern "C" size_t mbstowcs(wchar_t* _dst, const char* _src, size_t _max){	BX_UNUSED(_dst, _src, _max);	return 0;}

uint32_t objToBin(const uint8_t* _objData                  , bx::WriterSeekerI* _writer                  , uint32_t _packUv                  , uint32_t _packNormal                  , bool _ccw                  , bool _flipV                  , bool _hasTangent                  , float _scale                 ){    int64_t parseElapsed = -bx::getHPCounter();    int64_t triReorderElapsed = 0;    const int64_t begin = _writer->seek();    Vector3Array positions;    Vector3Array normals;    Vector3Array texcoords;    Index3Map indexMap;    TriangleArray triangles;    BgfxGroupArray groups;    uint32_t num = 0;    MeshGroup group;    group.m_startTriangle = 0;    group.m_numTriangles = 0;    group.m_name = "";    group.m_material = "";    char commandLine[2048];    uint32_t len = sizeof(commandLine);    int argc;    char* argv[64];    const char* next = (const char*)_objData;    do    {        next = bx::tokenizeCommandLine(next, commandLine, len, argc, argv, BX_COUNTOF(argv), '/n');        if (0 < argc)        {            if (0 == strcmp(argv[0], "#") )            {                if (2 < argc                        &&  0 == strcmp(argv[2], "polygons") )                {                }            }            else if (0 == strcmp(argv[0], "f") )            {                Triangle triangle;                memset(&triangle, 0, sizeof(Triangle) );                const int numNormals   = (int)normals.size();                const int numTexcoords = (int)texcoords.size();                const int numPositions = (int)positions.size();                for (uint32_t edge = 0, numEdges = argc-1; edge < numEdges; ++edge)                {                    Index3 index;                    index.m_texcoord = 0;                    index.m_normal = 0;                    index.m_vertexIndex = -1;                    char* vertex = argv[edge+1];                    char* texcoord = strchr(vertex, '/');                    if (NULL != texcoord)                    {                        *texcoord++ = '/0';                        char* normal = strchr(texcoord, '/');                        if (NULL != normal)                        {                            *normal++ = '/0';                            const int nn = atoi(normal);                            index.m_normal = (nn < 0) ? nn+numNormals : nn-1;                        }                        const int tex = atoi(texcoord);                        index.m_texcoord = (tex < 0) ? tex+numTexcoords : tex-1;                    }                    const int pos = atoi(vertex);                    index.m_position = (pos < 0) ? pos+numPositions : pos-1;                    uint64_t hash0 = index.m_position;                    uint64_t hash1 = uint64_t(index.m_texcoord)<<20;                    uint64_t hash2 = uint64_t(index.m_normal)<<40;                    uint64_t hash = hash0^hash1^hash2;                    CS_STL::pair<Index3Map::iterator, bool> result = indexMap.insert(CS_STL::make_pair(hash, index) );                    if (!result.second)                    {                        Index3& oldIndex = result.first->second;                        BX_UNUSED(oldIndex);                        BX_CHECK(oldIndex.m_position == index.m_position                                 && oldIndex.m_texcoord == index.m_texcoord                                 && oldIndex.m_normal == index.m_normal                                 , "Hash collision!"                                );                    }//.........这里部分代码省略.........

//.........这里部分代码省略.........				);			HDC hdc = GetDC(hwnd);			BGFX_FATAL(NULL != hdc, Fatal::UnableToInitialize, "GetDC failed!");			HGLRC context = createContext(hdc);			wglGetExtensionsStringARB = (PFNWGLGETEXTENSIONSSTRINGARBPROC)wglGetProcAddress("wglGetExtensionsStringARB");			wglChoosePixelFormatARB = (PFNWGLCHOOSEPIXELFORMATARBPROC)wglGetProcAddress("wglChoosePixelFormatARB");			wglCreateContextAttribsARB = (PFNWGLCREATECONTEXTATTRIBSARBPROC)wglGetProcAddress("wglCreateContextAttribsARB");			wglSwapIntervalEXT = (PFNWGLSWAPINTERVALEXTPROC)wglGetProcAddress("wglSwapIntervalEXT");			if (NULL != wglGetExtensionsStringARB)			{				const char* extensions = (const char*)wglGetExtensionsStringARB(hdc);				BX_TRACE("WGL extensions:");				dumpExtensions(extensions);			}			if (NULL != wglChoosePixelFormatARB			&&  NULL != wglCreateContextAttribsARB)			{				int32_t attrs[] =				{					WGL_SAMPLE_BUFFERS_ARB, 0,					WGL_SAMPLES_ARB, 0,					WGL_SUPPORT_OPENGL_ARB, true,					WGL_PIXEL_TYPE_ARB, WGL_TYPE_RGBA_ARB,					WGL_DRAW_TO_WINDOW_ARB, true,					WGL_DOUBLE_BUFFER_ARB, true,					WGL_COLOR_BITS_ARB, 32,					WGL_DEPTH_BITS_ARB, 24,					WGL_STENCIL_BITS_ARB, 8,					0				};				int result;				int pixelFormat;				uint32_t numFormats = 0;				do 				{					result = wglChoosePixelFormatARB(m_hdc, attrs, NULL, 1, &pixelFormat, &numFormats);					if (0 == result						||  0 == numFormats)					{						attrs[3] >>= 1;						attrs[1] = attrs[3] == 0 ? 0 : 1;					}				} while (0 == numFormats);				PIXELFORMATDESCRIPTOR pfd;				DescribePixelFormat(m_hdc, pixelFormat, sizeof(PIXELFORMATDESCRIPTOR), &pfd);				BX_TRACE("Pixel format:/n"					"/tiPixelType %d/n"					"/tcColorBits %d/n"					"/tcAlphaBits %d/n"					"/tcDepthBits %d/n"					"/tcStencilBits %d/n"					, pfd.iPixelType					, pfd.cColorBits					, pfd.cAlphaBits					, pfd.cDepthBits					, pfd.cStencilBits					);				result = SetPixelFormat(m_hdc, pixelFormat, &pfd);				// When window is created by SDL and SDL_WINDOW_OPENGL is set SetPixelFormat				// will fail. Just warn and continue. In case it failed for some other reason				// create context will fail and it will error out there.				BX_WARN(result, "SetPixelFormat failed (last err: 0x%08x)!", GetLastError() );				uint32_t flags = BGFX_CONFIG_DEBUG ? WGL_CONTEXT_DEBUG_BIT_ARB : 0;				BX_UNUSED(flags);				int32_t contextAttrs[9] =				{#if BGFX_CONFIG_RENDERER_OPENGL >= 31					WGL_CONTEXT_MAJOR_VERSION_ARB, 3,					WGL_CONTEXT_MINOR_VERSION_ARB, 1,					WGL_CONTEXT_FLAGS_ARB, flags,					WGL_CONTEXT_PROFILE_MASK_ARB, WGL_CONTEXT_CORE_PROFILE_BIT_ARB,#else					WGL_CONTEXT_MAJOR_VERSION_ARB, 2,					WGL_CONTEXT_MINOR_VERSION_ARB, 1,					0, 0,					0, 0,#endif // BGFX_CONFIG_RENDERER_OPENGL >= 31					0				};				m_context = wglCreateContextAttribsARB(m_hdc, 0, contextAttrs);				if (NULL == m_context)				{					// nVidia doesn't like context profile mask for contexts below 3.2?					contextAttrs[6] = WGL_CONTEXT_PROFILE_MASK_ARB == contextAttrs[6] ? 0 : contextAttrs[6];					m_context = wglCreateContextAttribsARB(m_hdc, 0, contextAttrs);				}				BGFX_FATAL(NULL != m_context, Fatal::UnableToInitialize, "Failed to create context 0x%08x.", GetLastError() );			}

extern "C" float floorf(float _x){	BX_UNUSED(_x);	return 0.0f;}

extern "C" double pow(double _x){	BX_UNUSED(_x);	return 0.0;}

extern "C" double floor(double _x){	BX_UNUSED(_x);	return 0.0;}

extern "C" float tanf(float _x){	BX_UNUSED(_x);	return 0.0f;}

extern "C" float fmodf(float _numer, float _denom){	BX_UNUSED(_numer, _denom);	return 0.0f;}

extern "C" float atan2f(float _y, float _x){	BX_UNUSED(_y, _x);	return 0.0f;}

extern "C" struct dirent* readdir(struct DIR* dirp){	BX_UNUSED(dirp);	return NULL;}

extern "C" float sqrtf(float _x){	BX_UNUSED(_x);	return 0.0f;}

extern "C" int printf(const char* _format, ...){	BX_UNUSED(_format);	return -1;}

extern "C" double sqrt(double _x){	BX_UNUSED(_x);	return 0.0;}

extern "C" int sscanf(const char* _str, const char* _format, ...){	BX_UNUSED(_str, _format);	return -1;}

extern "C" float ceilf(float _x){	BX_UNUSED(_x);	return 0.0f;}

extern "C" FILE* fopen(const char* _filename, const char* _mode){	BX_UNUSED(_filename, _mode);	return NULL;}

extern "C" double ceil(double _x){	BX_UNUSED(_x);	return 0.0;}

extern "C" size_t fwrite(const void* _ptr, size_t _size, size_t _count, FILE* _stream){	BX_UNUSED(_ptr, _size, _count, _stream);	return -1;}

	void toggleFullscreen(WindowHandle _handle)	{		BX_UNUSED(_handle);	}