OpenGL: How to check if the user supports glGenBuffers()?

问题

I checked docs, and it says OpenGL version must be at least 1.5 to make glGenBuffers() work. The user has version 1.5 but the function call will cause a crash. Is this a mistake in the docs, or a driver problem on the user?

I am using this glGenBuffers() for VBO, how do i check if the user has support for this?

Edit: im using glew with glewInit() to initialize VBO

Edit2: I got it working on the user with glGenBuffersARB() function calls. But im still looking a way to find out when should i use glGenBuffers() and when should i use glGenBuffersARB() AND when should i use VertexArrays if none of the VBO function calls are supported.

I also found out that if(GLEW_VERSION_1_5) returns false on the user, but GL_VERSION gives 1.5.0, which just doesnt make any sense!

回答1:

I'm going to tell you now to stay far away from GLEW or any of these libraries mostly because they're useless, this is how I have always done it.

#ifndef STRINGIFY
  #define STRINGIFY(x) #x
#endif
#ifdef WIN32
  #include <windows.h>
  #define glGetProcAddress(a) wglGetProcAddress(a)
#endif
#ifdef X11
  #define glGetProcAddress(a) glXGetProcAddress ( \
    reinterpret_cast<const unsigned char*>(a)     \
  )
#endif

#ifndef GetExtension
  #define GetExtension(Type, ExtenName)     \
    ExtenName = (Type)                      \
    glGetProcAddress(STRINGIFY(ExtenName)); \
    if(!ExtenName)                          \
    {                                       \
      std:cout << "Your Computer Does Not " \
               << "Support GL Extension: "  \
               << STRINGIFY(ExtenName)      \
               << std::endl;                \
      exit(1);                              \         
    }                                       \
    else                                    \
    {                                       \
      std::cout << "Loadded Extension: "    \
                << STRINGIFY(ExtenName)     \
                << std::endl;               \
    }
#endif

// then just use this :D
GetExtension(PFNGLGENBUFFERSARBPROC, glGenBuffersARB)
// after your done you can do this
#undef GetExtension
#undef glGetProcAddress
// you can then also undef the STRINGIFY macro
// though it does come in handy.

回答2:

Check this link. Maybe it will help you;)

if (GLEW_VERSION_1_5)
{
  /* You have OpenGL 1.5 */
}

Try glGenBuffersARB insted glGenBuffers; I think you only need to check 1.5 support;

来源：https://stackoverflow.com/questions/4317062/opengl-how-to-check-if-the-user-supports-glgenbuffers

标签

c++

visual-studio-2008

opengl