source/extension.cpp

   1 #include <set>
   2 #include <cstdlib>
   3 #if defined(__ANDROID__)
   4 #include <EGL/egl.h>
   5 #elif !defined(_WIN32) && !defined(__APPLE__)
   6 #define GLX_GLXEXT_PROTOTYPES
   7 #include <GL/glx.h>
   8 #endif
   9 #include <msp/strings/format.h>
  10 #include <msp/strings/utils.h>
  11 #include "error.h"
  12 #include "extension.h"
  13 #include "gl.h"
  14
  15 using namespace std;
  16
  17 namespace Msp {
  18 namespace GL {
  19
  20 Version::Version()
  21 {
  22         major = 0;
  23         minor = 0;
  24 }
  25
  26 Version::Version(unsigned short a, unsigned short i)
  27 {
  28         major = a;
  29         minor = i;
  30 }
  31
  32 Version::Version(const string &s)
  33 {
  34         vector<string> parts = split(s, '.');
  35         major = lexical_cast<unsigned>(parts[0]);
  36         minor = lexical_cast<unsigned>(parts[1]);
  37 }
  38
  39 bool Version::operator>=(const Version &other) const
  40 {
  41         return major>other.major || (major==other.major && minor>=other.minor);
  42 }
  43
  44
  45 Extension::Extension(const char *n, InitFunc f):
  46         name(n),
  47         init_func(f),
  48         init_done(false),
  49         support(UNSUPPORTED)
  50 { }
  51
  52 Extension::operator bool() const
  53 {
  54         if(!init_done)
  55         {
  56                 support = init_func();
  57                 init_done = true;
  58         }
  59
  60         return support>UNSUPPORTED;
  61 }
  62
  63
  64 Require::Require(const Extension &ext)
  65 {
  66         if(!ext)
  67                 throw unsupported_extension(ext.get_name());
  68 }
  69
  70
  71 bool is_supported(const string &ext)
  72 {
  73         static set<string> extensions;
  74         static bool init_done = false;
  75
  76         if(!init_done)
  77         {
  78                 if(const char *gl_ext = reinterpret_cast<const char *>(glGetString(GL_EXTENSIONS)))
  79                 {
  80                         vector<string> exts = split(gl_ext);
  81                         extensions.insert(exts.begin(), exts.end());
  82                 }
  83
  84                 if(const char *renderer_ptr = reinterpret_cast<const char *>(glGetString(GL_RENDERER)))
  85                 {
  86                         string renderer = renderer_ptr;
  87                         if(renderer.find("Radeon")!=string::npos || renderer.find("AMD")!=string::npos)
  88                         {
  89                                 /* Radeon doesn't process NV_primitive_restart correctly and treats
  90                                 the restart index as a normal element if the indices are stored in a
  91                                 buffer. */
  92                                 extensions.erase("GL_NV_primitive_restart");
  93
  94                                 /* AMD's uniform buffer objects only work with the core version of
  95                                 shaders. */
  96                                 if(!(get_gl_version()>=Version(2, 0)))
  97                                         extensions.erase("GL_ARB_uniform_buffer_object");
  98                         }
  99                 }
 100
 101                 if(const char *disable_ptr = getenv("MSPGL_DISABLE_EXTENSIONS"))
 102                 {
 103                         vector<string> disable = split(disable_ptr);
 104                         for(vector<string>::const_iterator i=disable.begin(); i!=disable.end(); ++i)
 105                                 extensions.erase(*i);
 106                 }
 107
 108                 init_done = true;
 109         }
 110
 111         return extensions.count(ext);
 112 }
 113
 114 GLApi get_gl_api()
 115 {
 116 #ifdef GL_ES_VERSION_2_0
 117         return OPENGL_ES2;
 118 #else
 119         return OPENGL;
 120 #endif
 121 }
 122
 123 inline Version _get_gl_version()
 124 {
 125         const char *gl_ver_ptr = reinterpret_cast<const char *>(glGetString(GL_VERSION));
 126         if(!gl_ver_ptr)
 127                 throw runtime_error("OpenGL version not available");
 128
 129         string gl_ver = gl_ver_ptr;
 130         if(!gl_ver.compare(0, 10, "OpenGL ES "))
 131                 gl_ver.erase(0, 10);
 132
 133         Version ver(gl_ver.substr(0, gl_ver.find(' ')));
 134
 135         if(const char *force_ver_ptr = getenv("MSPGL_FORCE_VERSION"))
 136         {
 137                 Version force_ver(force_ver_ptr);
 138                 if(!(force_ver>=ver))
 139                         ver = force_ver;
 140         }
 141
 142         return ver;
 143 }
 144
 145 const Version &get_gl_version()
 146 {
 147         static Version version = _get_gl_version();
 148         return version;
 149 }
 150
 151 inline Version _get_glsl_version()
 152 {
 153         const char *glsl_ver_ptr = reinterpret_cast<const char *>(glGetString(GL_SHADING_LANGUAGE_VERSION));
 154         if(!glsl_ver_ptr)
 155                 throw runtime_error("GLSL version not available");
 156
 157         string glsl_ver = glsl_ver_ptr;
 158         if(!glsl_ver.compare(0, 18, "OpenGL ES GLSL ES "))
 159                 glsl_ver.erase(0, 18);
 160
 161         Version ver(glsl_ver.substr(0, glsl_ver.find(' ')));
 162
 163         if(const char *force_ver_ptr = getenv("MSPGL_FORCE_GLSL_VERSION"))
 164         {
 165                 Version force_ver(force_ver_ptr);
 166                 if(!(force_ver>=ver))
 167                         ver = force_ver;
 168         }
 169
 170         return ver;
 171 }
 172
 173 const Version &get_glsl_version()
 174 {
 175         static Version version = _get_glsl_version();
 176         return version;
 177 }
 178
 179 bool is_version_at_least(unsigned a, unsigned b)
 180 {
 181         return get_gl_version()>=Version(a, b);
 182 }
 183
 184 ExtFunc *get_proc_address(const string &name)
 185 {
 186 #if defined(WIN32)
 187         return reinterpret_cast<ExtFunc *>(wglGetProcAddress(name.c_str()));
 188 #elif defined(__APPLE__)
 189         (void)name;
 190         return 0;  // Not supported
 191 #elif defined(__ANDROID__)
 192         return eglGetProcAddress(name.c_str());
 193 #else
 194         return glXGetProcAddressARB(reinterpret_cast<const unsigned char *>(name.c_str()));
 195 #endif
 196 }
 197
 198 } // namespace GL
 199 } // namespace Msp