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 "arb_shader_objects.h"
   9 #include "arb_vertex_buffer_object.h"
  10 #include "arb_vertex_program.h"
  11 #include "arb_vertex_shader.h"
  12 #include "ext_framebuffer_blit.h"
  13 #include "ext_framebuffer_multisample.h"
  14 #include "ext_framebuffer_object.h"
  15 #include "except.h"
  16 #include "extension.h"
  17 #include "gl.h"
  18 #include "nv_primitive_restart.h"
  19 #include "version_1_2.h"
  20 #include "version_1_3.h"
  21
  22 using namespace std;
  23
  24 namespace Msp {
  25 namespace GL {
  26
  27 bool is_supported(const string &ext)
  28 {
  29         static set<string> extensions;
  30         static bool init_done = false;
  31
  32         if(!init_done)
  33         {
  34                 if(const char *gl_ext = reinterpret_cast<const char *>(glGetString(GL_EXTENSIONS)))
  35                 {
  36                         vector<string> exts = split(gl_ext);
  37                         extensions.insert(exts.begin(), exts.end());
  38                 }
  39
  40                 /* XXX Conceptually a bit weird place for this, but I couldn't really come up
  41                    with anything better that would still be transparent. */
  42                 if(extensions.count("GL_ARB_shader_objects"))
  43                         init_arb_shader_objects();
  44                 if(extensions.count("GL_ARB_vertex_shader"))
  45                         init_arb_vertex_shader();
  46                 if(extensions.count("GL_ARB_vertex_program"))
  47                         init_arb_vertex_program();
  48                 if(extensions.count("GL_EXT_framebuffer_object"))
  49                         init_ext_framebuffer_object();
  50                 if(extensions.count("GL_EXT_framebuffer_blit"))
  51                         init_ext_framebuffer_blit();
  52                 if(extensions.count("GL_EXT_framebuffer_multisample"))
  53                         init_ext_framebuffer_multisample();
  54                 if(extensions.count("GL_ARB_vertex_buffer_object"))
  55                         init_arb_vertex_buffer_object();
  56                 if(extensions.count("GL_NV_primitive_restart"))
  57                         init_nv_primitive_restart();
  58
  59                 init_done = true;
  60         }
  61
  62         return extensions.count(ext);
  63 }
  64
  65 void require_extension(const string &ext)
  66 {
  67         if(!is_supported(ext))
  68                 throw UnsupportedExtension(ext);
  69 }
  70
  71 const Version &get_gl_version()
  72 {
  73         static Version version;
  74         static bool init_done = false;
  75
  76         if(!init_done)
  77         {
  78                 string gl_ver = reinterpret_cast<const char *>(glGetString(GL_VERSION));
  79                 vector<string> parts = split(gl_ver.substr(0, gl_ver.find(' ')), '.');
  80                 version.major = lexical_cast<unsigned>(parts[0]);
  81                 version.minor = lexical_cast<unsigned>(parts[1]);
  82
  83                 unsigned combined = version.major*0x100+version.minor;
  84                 if(combined>=0x102)
  85                         init_version_1_2();
  86                 if(combined>=0x103)
  87                         init_version_1_3();
  88
  89                 init_done = true;
  90         }
  91
  92         return version;
  93 }
  94
  95 bool is_version_at_least(unsigned a, unsigned b)
  96 {
  97         const Version &ver = get_gl_version();
  98         return (ver.major>a || (ver.major==a && ver.minor>=b));
  99 }
 100
 101 void require_version(unsigned a, unsigned b)
 102 {
 103         if(!is_version_at_least(a, b))
 104                 throw UnsupportedExtension(format("OpenGL %d.%d", a, b));
 105 }
 106
 107 ExtFunc *get_proc_address(const string &name)
 108 {
 109 #ifndef WIN32
 110         return glXGetProcAddressARB(reinterpret_cast<const unsigned char *>(name.c_str()));
 111 #else
 112         return reinterpret_cast<ExtFunc *>(wglGetProcAddress(name.c_str()));
 113 #endif
 114 }
 115
 116 } // namespace GL
 117 } // namespace Msp