// Various utilities.
+#include <GL/glew.h>
#include <stdio.h>
#include <stdlib.h>
-
-#include <string>
#include <Eigen/Core>
-
-#include "opengl.h"
+#include <string>
#define BUFFER_OFFSET(i) ((char *)NULL + (i))
#define check_error() { int err = glGetError(); if (err != GL_NO_ERROR) { printf("GL error 0x%x at %s:%d\n", err, __FILE__, __LINE__); exit(1); } }
#endif
+#ifdef __GNUC__
+#define MUST_CHECK_RESULT __attribute__((warn_unused_result))
+#else
+#define MUST_CHECK_RESULT
+#endif
+
+// CHECK() is like assert(), but retains any side effects no matter the compilation mode.
+#ifdef NDEBUG
+#define CHECK(x) (void)(x)
+#else
+#define CHECK(x) do { bool ok = x; if (!ok) { fprintf(stderr, "%s:%d: %s: Assertion `%s' failed.\n", __FILE__, __LINE__, __PRETTY_FUNCTION__, #x); abort(); } } while (false)
+#endif
+
#endif // !defined(_UTIL_H)