2010 Khronos Group glGetFragDataLocation 3G glGetFragDataLocation query the bindings of color numbers to user-defined varying out variables GLint glGetFragDataLocation GLuint program const char * name program The name of the program containing varying out variable whose binding to query name The name of the user-defined varying out variable whose binding to query glGetFragDataLocation retrieves the assigned color number binding for the user-defined varying out variable name for program program. program must have previously been linked. name must be a null-terminated string. If name is not the name of an active user-defined varying out fragment shader variable within program, -1 will be returned. GL_INVALID_OPERATION is generated if program is not the name of a program object. glCreateProgram, glBindFragDataLocation Copyright 2010 Khronos Group. This material may be distributed subject to the terms and conditions set forth in the Open Publication License, v 1.0, 8 June 1999. http://opencontent.org/openpub/.