GL_ARB_occlusion_query http://oss.sgi.com/projects/ogl-sample/registry/ARB/occlusion_query.txt GL_QUERY_COUNTER_BITS_ARB 0x8864 GL_CURRENT_QUERY_ARB 0x8865 GL_QUERY_RESULT_ARB 0x8866 GL_QUERY_RESULT_AVAILABLE_ARB 0x8867 GL_SAMPLES_PASSED_ARB 0x8914 void glBeginQueryARB (GLenum target, GLuint id) void glDeleteQueriesARB (GLsizei n, const GLuint* ids) void glEndQueryARB (GLenum target) void glGenQueriesARB (GLsizei n, GLuint* ids) void glGetQueryObjectivARB (GLuint id, GLenum pname, GLint* params) void glGetQueryObjectuivARB (GLuint id, GLenum pname, GLuint* params) void glGetQueryivARB (GLenum target, GLenum pname, GLint* params) GLboolean glIsQueryARB (GLuint id)