source/extension.cpp

   1 #include <set>
   2 #ifndef WIN32
   3 #define GLX_GLXEXT_PROTOTYPES
   4 #include <GL/glx.h>
   5 #endif
   6 #include <msp/strings/format.h>
   7 #include <msp/strings/utils.h>
   8 #include "error.h"
   9 #include "extension.h"
  10 #include "gl.h"
  11
  12 using namespace std;
  13
  14 namespace Msp {
  15 namespace GL {
  16
  17 Extension::Extension(const char *n, InitFunc f):
  18         name(n),
  19         init_func(f),
  20         init_done(false),
  21         support(UNSUPPORTED)
  22 { }
  23
  24 Extension::operator bool() const
  25 {
  26         if(!init_done)
  27         {
  28                 support = init_func();
  29                 init_done = true;
  30         }
  31
  32         return support>UNSUPPORTED;
  33 }
  34
  35
  36 Require::Require(const Extension &ext)
  37 {
  38         if(!ext)
  39                 throw unsupported_extension(ext.get_name());
  40 }
  41
  42
  43 bool is_supported(const string &ext)
  44 {
  45         static set<string> extensions;
  46         static bool init_done = false;
  47
  48         if(!init_done)
  49         {
  50                 if(const char *gl_ext = reinterpret_cast<const char *>(glGetString(GL_EXTENSIONS)))
  51                 {
  52                         vector<string> exts = split(gl_ext);
  53                         extensions.insert(exts.begin(), exts.end());
  54                 }
  55
  56                 init_done = true;
  57         }
  58
  59         return extensions.count(ext);
  60 }
  61
  62 const Version &get_gl_version()
  63 {
  64         static Version version;
  65         static bool init_done = false;
  66
  67         if(!init_done)
  68         {
  69                 string gl_ver = reinterpret_cast<const char *>(glGetString(GL_VERSION));
  70                 vector<string> parts = split(gl_ver.substr(0, gl_ver.find(' ')), '.');
  71                 version.major = lexical_cast<unsigned>(parts[0]);
  72                 version.minor = lexical_cast<unsigned>(parts[1]);
  73
  74                 init_done = true;
  75         }
  76
  77         return version;
  78 }
  79
  80 bool is_version_at_least(unsigned a, unsigned b)
  81 {
  82         const Version &ver = get_gl_version();
  83         return (ver.major>a || (ver.major==a && ver.minor>=b));
  84 }
  85
  86 ExtFunc *get_proc_address(const string &name)
  87 {
  88 #ifndef WIN32
  89         return glXGetProcAddressARB(reinterpret_cast<const unsigned char *>(name.c_str()));
  90 #else
  91         return reinterpret_cast<ExtFunc *>(wglGetProcAddress(name.c_str()));
  92 #endif
  93 }
  94
  95 } // namespace GL
  96 } // namespace Msp