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OpenGL Getting Useful System Information

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I've looked around everywhere and posted on several forums but so far I haven't gotten a single useful answer to this: I've been using OpenGL for quite some time now and now want to make my demo's a little smarter in how they set things up. But to do so I want to be able to find information about the current system it's running on and enable/disable things as such. I have no problems with extensions but it's other types of information that I can't find. -RAM/VRAM -Processor speed/maker/cores -Textures per pass -Pixel/Vertex Shader version/pipelines I'm sure there are a few other related ones that just don't come to mind at the moment. I have seen a few ways to get this information on DX but that's why I posted it here in the OpenGL forum. So far I haven't been able to find any functions in OpenGL to get this kind of information but if there are any other supplementary libraries that would do it I would be just as happy. Thanks in advance for any help. ~Chao

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Here's some code from my engine (it may not compile as it is btw) :

bool cRender::Init(void)

// Recuperation des ecrans et modes d'affichages disponibles
int displaynum = 0;
memset(&display, 0, sizeof(display));
display.cb = sizeof(display);

// Liste des moniteurs installes
while(EnumDisplayDevices(NULL, displaynum++, &display, NULL))
// Moniteur de rendu
// DebugManager->Print(Debug, __FUNCTION__, "%s", display.DeviceString);

DEVMODE devmode;
memset(&devmode, 0, sizeof(devmode));
devmode.dmSize = sizeof(devmode);
int num = 0;
while (EnumDisplaySettings(display.DeviceName, num++, &devmode))
if (devmode.dmBitsPerPel >=16 && devmode.dmPelsWidth >= 640 && devmode.dmPelsHeight >= 480)
// DebugManager->Print(Debug, __FUNCTION__, "%ix%ix%i@%i",
// devmode.dmPelsWidth, devmode.dmPelsHeight, devmode.dmBitsPerPel, devmode.dmDisplayFrequency);

// matrix stack
glGetIntegerv(GL_MATRIX_MODE, &val); // Initial matrix mode
int val = 0;
char *txt = NULL;
log << "<b>GL_MAX_MODELVIEW_STACK_DEPTH</b> = " << val << NewLine;

log << "<b>GL_MAX_PROJECTION_STACK_DEPTH</b> = " << val << NewLine;

glGetIntegerv(GL_MAX_TEXTURE_STACK_DEPTH, &val);
log << "<b>GL_MAX_TEXTURE_STACK_DEPTH</b> = " << val << NewLine;

// Infos sur la carte graphique
txt = (char *)glGetString(GL_VENDOR);
log << "<b>GL_VENDOR</b> = " << txt << NewLine;

txt = (char *)glGetString(GL_RENDERER);
log << "<b>GL_RENDERER</b> = " << txt << NewLine;

txt = (char *)glGetString(GL_VERSION);
log << "<b>GL_VERSION</b> = " << txt << NewLine;

txt = (char *)glGetString(GL_SHADING_LANGUAGE_VERSION);
log << "<b>GL_SL_VERSION</b> = " << txt << NewLine;

txt = (char *)glGetString(GL_EXTENSIONS );
log << "<b>GL_EXTENSIONS</b> = " << txt << NewLine;
log << wglGetExtensionsStringEXT();

// Initialisation de toutes les extensions

// ARB_vertex_buffer_object
if (EGL_HAS_GL_ARB_vertex_buffer_object)
DeviceCaps.HasVBO = true;
log << "ARB_vertex_buffer_object supported." << NewLine;

// GL_EXT_compiled_vertex_array
if (EGL_HAS_GL_EXT_compiled_vertex_array)
DeviceCaps.HasCVA = true;
log << "GL_EXT_compiled_vertex_array supported." << NewLine;

// ARB_vertex_program
if (EGL_HAS_GL_ARB_vertex_program)
DeviceCaps.HasVertexProgram = true;
log << "ARB_vertex_program supported." << NewLine;

// ARB_fragment_program
if (EGL_HAS_GL_ARB_fragment_program)
DeviceCaps.HasFragmentProgram = true;
log << "ARB_fragment_program supported." << NewLine;

// Transpose Matrix
if (EGL_HAS_GL_ARB_transpose_matrix)
HasTransposeMatrix = true;
log << "ARB_transpose_matrix supported." << NewLine;

// Transpose Matrix
if (EGL_HAS_GL_ARB_shader_objects)
DeviceCaps.HasShaderObjects = true;
log << "GL_ARB_shader_objects supported." << NewLine;

// Texture's part
glGetIntegerv(GL_MAX_TEXTURE_UNITS_ARB, (GLint *)param); // Max texture units
glGetIntegerv(GL_MAX_TEXTURE_SIZE, (GLint *)param); // Max texture size
glGetIntegerv(GL_MAX_LIGHTS, (GLint *)param); // Mas number of lights

// ARB_texture_compression
if (RenderManager->IsExtensionAvailable("ARB_texture_compression"))
TextureCompression = true;
log << "ARB_texture_compression supported";

// GL_EXT_texture_compression_s3tc
if (RenderManager->IsExtensionAvailable("GL_EXT_texture_compression_s3tc"))
TextureCompressionS3TC = true;
log << "GL_EXT_texture_compression_s3tc supported";

// GL_SGIS_generate_mipmap
if (RenderManager->IsExtensionAvailable("GL_SGIS_generate_mipmap"))
AutoGenerateMipMap = true;
log << "GL_SGIS_generate_mipmap supported";

// GL_EXT_texture_compression_s3tc
if (RenderManager->IsExtensionAvailable("GL_EXT_texture_filter_anisotropic"))
log << "GL_EXT_texture_filter_anisotropic supported";

// GL_EXT_bgra
if (RenderManager->IsExtensionAvailable("GL_EXT_bgra"))
BGRAFormat = true;
log << "Native BGRA texture format supported";


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And the hardware's part

string txt;

memset(&version, 0, sizeof(OSVERSIONINFOEX));
version.dwOSVersionInfoSize = sizeof(OSVERSIONINFOEX);
if (GetVersionEx((OSVERSIONINFO *)&version))
// Famille NT
if ( version.dwMajorVersion == 5 && version.dwMinorVersion == 2 )
txt = "Microsoft Windows Server 2003 family";

if ( version.dwMajorVersion == 5 && version.dwMinorVersion == 1 )
txt = "Microsoft Windows XP";

if ( version.dwMajorVersion == 5 && version.dwMinorVersion == 0 )
txt = "Microsoft Windows 2000";

if ( version.dwMajorVersion <= 4 )
txt = "Microsoft Windows NT";

// Service pack ?
if (version.szCSDVersion) txt += version.szCSDVersion;


// Famille 9x
if (version.dwMajorVersion == 4 && version.dwMinorVersion == 0)
txt = "Microsoft Windows 95 ";
if ( version.szCSDVersion[1] == 'C' || version.szCSDVersion[1] == 'B' )
txt += "OSR2";

if (version.dwMajorVersion == 4 && version.dwMinorVersion == 10)
txt = "Microsoft Windows 98 ";
if (version.szCSDVersion[1] == 'A') txt += "SE ";

if (version.dwMajorVersion == 4 && version.dwMinorVersion == 90)
txt = "Microsoft Windows Millennium Edition";

txt = "Unknown Operating System !!";

txt = "Unable to gather hardware informations.";

log << txt << ::NewLine;

// Memoire dispo
statex.dwLength = sizeof(statex);
log << "Available memory " << (statex.dwTotalPhys>>20) << "Mo (" << (statex.dwAvailPhys>>20)<< "Mo free)" << ::NewLine;

// Informations sur le(s) processeur(s)
log << "Number of processor(s) : " << sinfo.dwNumberOfProcessors;

// Lecture depuis la base de registre
HKEY key;
long result = RegOpenKeyEx(HKEY_LOCAL_MACHINE, "Hardware\\Description\\System\\CentralProcessor\\0",
0, KEY_QUERY_VALUE, &key);

if (result == ERROR_SUCCESS)

// Type de cpu - ProcessorNameString
DWORD size = 1024;
RegQueryValueEx(key, "ProcessorNameString", NULL, NULL, (LPBYTE)txt.c_str(), &size);
log << txt << ::NewLine;

// Identifiant - Identifier
size = 1024;
RegQueryValueEx(key, "Identifier", NULL, NULL, (LPBYTE)txt.c_str(), &size);
log << txt;


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