for a Debug build, glerror() prints any gl errors that have occurred

git-svn-id: https://projectm.svn.sourceforge.net/svnroot/projectm/trunk@734 6778bc44-b910-0410-a7a0-be141de4315d

src/projectM-engine/glError.h

@@ -0,0 +1,31 @@
+//
+// File:   glError.h
+// Author: fatray
+//
+// Created on 02 December 2007, 16:08
+//
+
+#ifndef _GLERROR_H
+#define	_GLERROR_H
+
+// no need to include GL in here, 
+// if someone wants GL errors they probably already included it.
+
+
+/*
+ * if we are debugging, print all glErrors to stderr.
+ * Remeber that glErrors are buffered, this just prints any in the buffer.
+ */
+#ifdef NDEBUG
+#define glError()
+#else
+#define glError() { \
+	GLenum err; \
+	while ((err = glGetError()) != GL_NO_ERROR) \
+		fprintf(stderr, "glError: %s at %s:%u\n", \
+			(char *)gluErrorString(err), __FILE__, __LINE__); \
+}
+#endif	/* glError */
+
+#endif	/* _GLERROR_H */
+