source/extension.cpp

   1 /* $Id$
   2
   3 This file is part of libmspgl
   4 Copyright © 2007  Mikko Rasa, Mikkosoft Productions
   5 Distributed under the LGPL
   6 */
   7
   8 #include <set>
   9 #ifndef WIN32
  10 #include <GL/glx.h>
  11 #endif
  12 #include <msp/strings/formatter.h>
  13 #include <msp/strings/utils.h>
  14 #include "arb_shader_objects.h"
  15 #include "arb_vertex_buffer_object.h"
  16 #include "arb_vertex_shader.h"
  17 #include "ext_framebuffer_object.h"
  18 #include "except.h"
  19 #include "extension.h"
  20 #include "gl.h"
  21 #include "version_1_2.h"
  22 #include "version_1_3.h"
  23
  24 using namespace std;
  25
  26 namespace Msp {
  27 namespace GL {
  28
  29 bool is_supported(const string &ext)
  30 {
  31         static set<string> extensions;
  32         static bool init_done=false;
  33
  34         if(!init_done)
  35         {
  36                 if(const char *gl_ext=reinterpret_cast<const char *>(glGetString(GL_EXTENSIONS)))
  37                 {
  38                         vector<string> exts=split(gl_ext);
  39                         extensions.insert(exts.begin(), exts.end());
  40                 }
  41
  42                 /* XXX Conceptually a bit weird place for this, but I couldn't really come up
  43                    with anything better that would still be transparent. */
  44                 if(extensions.count("GL_ARB_shader_objects"))
  45                         init_arb_shader_objects();
  46                 if(extensions.count("GL_ARB_vertex_shader"))
  47                         init_arb_vertex_shader();
  48                 if(extensions.count("GL_EXT_framebuffer_object"))
  49                         init_ext_framebuffer_object();
  50                 if(extensions.count("GL_ARB_vertex_buffer_object"))
  51                         init_arb_vertex_buffer_object();
  52
  53                 init_done=true;
  54         }
  55
  56         return extensions.count(ext);
  57 }
  58
  59 const Version &get_gl_version()
  60 {
  61         static Version version;
  62         static bool init_done=false;
  63
  64         if(!init_done)
  65         {
  66                 string gl_ver=reinterpret_cast<const char *>(glGetString(GL_VERSION));
  67                 vector<string> parts=split(gl_ver.substr(0, gl_ver.find(' ')), '.');
  68                 version.major=lexical_cast<unsigned>(parts[0]);
  69                 version.minor=lexical_cast<unsigned>(parts[1]);
  70
  71                 unsigned combined=version.major*0x100+version.minor;
  72                 if(combined>=0x102)
  73                         init_version_1_2();
  74                 if(combined>=0x103)
  75                         init_version_1_3();
  76         }
  77
  78         return version;
  79 }
  80
  81 void require_extension(const string &ext)
  82 {
  83         if(!is_supported(ext))
  84                 throw UnsupportedExtension(ext);
  85 }
  86
  87 void require_version(unsigned a, unsigned b)
  88 {
  89         const Version &ver=get_gl_version();
  90         if(ver.major<a || (ver.major==a && ver.minor<b))
  91                 throw UnsupportedExtension(format("OpenGL %d.%d", a, b));
  92 }
  93
  94 ExtFunc *get_proc_address(const string &name)
  95 {
  96 #ifndef WIN32
  97         return glXGetProcAddressARB(reinterpret_cast<const GLubyte *>(name.c_str()));
  98 #else
  99         return reinterpret_cast<ExtFunc *>(wglGetProcAddress(name.c_str()));
 100 #endif
 101 }
 102
 103 } // namespace GL
 104 } // namespace Msp