#include <GL/glut.h> #include <error.h> #include <errno.h> void check_error (const char *filename, unsigned int linenum) { GLenum errCode = glGetError (); if (errCode != GL_NO_ERROR) { const GLubyte *errString = gluErrorString (errCode); error_at_line (-1, errno, filename, linenum, "OpenGL Error %s", errString); } return; }