From b2f6707efc2ce5e639671551060da62f878b799a Mon Sep 17 00:00:00 2001
From: PedroEdiaz <ppedroediaz@gmail.com>
Date: Tue, 3 Dec 2024 22:51:50 -0600
Subject: [PATCH] Update norm.h to be safe

---
 include/klein/norm.h | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/include/klein/norm.h b/include/klein/norm.h
index bca38f3..72b1729 100644
--- a/include/klein/norm.h
+++ b/include/klein/norm.h
@@ -1,3 +1,16 @@
+#ifdef KLEIN_NORM_H
+#error file included twice
+#endif
+#define KLEIN_NORM_H
+
+
+#ifndef KLEIN_H
+#warning Please include klein/klein.h
+#endif
+
+void klein_normalize(struct klein * klein);
+
+#ifdef KLEIN_IMPLEMENT
 static inline
 void __calculate_normal( float *p1, float *p2, float *p3, float *normal, unsigned char n)
 { unsigned char i;
@@ -116,3 +129,4 @@ void klein_normalize(struct klein * klein)
 
 	free(norm_vec);
 }
+#endif