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gl.cc
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40 \*===========================================================================*/
41 
42 #include "gl.hh"
43 
44 #include <cstdlib>
45 #include <sstream>
46 #include <iostream>
47 
48 
49 
50 //=============================================================================
51 namespace ACG {
52 //=============================================================================
53 namespace {
60 inline const char *_getExtensionString() {
61  const char *supported_cstr = reinterpret_cast<const char*>(glGetString(GL_EXTENSIONS));
62  if (supported_cstr == 0) {
63  std::cerr << "\x1b[1;31mACG::checkExtensionsSupported: "
64  "glGetString(GL_EXTENSIONS) call failed.\x1b[0m\n";
65  return "";
66  }
67  return supported_cstr;
68 }
69 }
70 
73 bool checkExtensionSupported( const std::string& _extension ) {
78  static const std::string supported_str(_getExtensionString());
79 
80  /*
81  * supported_str is a space delimited list. Tokenize it. Simply searching
82  * for _extension within supported_str yields false positives if the
83  * requested extension is a substring of a supported one.
84  */
85  for (std::istringstream supported(supported_str); !supported.eof(); ) {
86  std::string feature;
87  supported >> feature;
88  if (feature == _extension) return true;
89  }
90  return false;
91 }
92 
95 bool openGLVersion( const int _major, const int _minor ) {
96 
97  // Read OpenGL Version string
98  std::string glVersionString = (const char*)glGetString(GL_VERSION);
99 
100  // Use string stream to parse
101  std::istringstream stream;
102  stream.str(glVersionString);
103 
104  // Buffer for the dot between major and minor
105  char dot;
106 
107  // Read Major version number
108  int major ;
109  stream >> major;
110  stream >> dot;
111 
112  // Read minor version number
113  int minor;
114  stream >> minor;
115 
116  if ( (_major > major) || ( (_major == major) && (_minor > minor)) ) {
117  std::cerr << "OpenGL Version check failed. Required : " << _major << "." << _minor << std::endl;
118  std::cerr << "OpenGL Version check failed. Available : " << major << "." << minor << std::endl;
119  return false;
120  }
121 
122  return true;
123 }
124 
125 
126 //=============================================================================
127 } // namespace ACG
128 //=============================================================================
Namespace providing different geometric functions concerning angles.
Definition: DBSCANT.cc:51
bool openGLVersion(const int _major, const int _minor)
Definition: gl.cc:95
bool checkExtensionSupported(const std::string &_extension)
Definition: gl.cc:73