From 8aa3bbe29e6f91ee510bb3017eb7df9280b5a4d9 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Miloslav=20=C4=8C=C3=AD=C5=BE?= <tastyfish@seznam.cz>
Date: Sun, 12 May 2019 15:07:18 +0200
Subject: [PATCH] Fix zero division

---
 s3l.h | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/s3l.h b/s3l.h
index 026cd09..4830090 100644
--- a/s3l.h
+++ b/s3l.h
@@ -1355,8 +1355,10 @@ void S3L_makeCameraMatrix(S3L_Transform3D cameraTransform, S3L_Mat4 *m)
 static inline void S3L_perspectiveDivide(S3L_Vec4 *vector,
   S3L_Unit focalLength)
 {
-  vector->x = (vector->x * focalLength) / vector->z;
-  vector->y = (vector->y * focalLength) / vector->z;
+  S3L_Unit divisor = S3L_nonZero(vector->z);
+
+  vector->x = (vector->x * focalLength) / divisor;
+  vector->y = (vector->y * focalLength) / divisor;
 }
 
 void S3L_drawModelIndexed(