From 121c996c6e51ab6e03c42543c8704876863a0f69 Mon Sep 17 00:00:00 2001
From: Eike Decker <zet23t@googlemail.com>
Date: Fri, 1 Aug 2025 08:40:28 +0200
Subject: [PATCH] fixing OBJ loading crash when there are no normals present

---
 src/rmodels.c | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/src/rmodels.c b/src/rmodels.c
index 0dc7572f1..246c2b0a3 100644
--- a/src/rmodels.c
+++ b/src/rmodels.c
@@ -4473,9 +4473,17 @@ static Model LoadOBJ(const char *fileName)
 
             for (int i = 0; i < 3; i++) model.meshes[meshIndex].vertices[localMeshVertexCount*3 + i] = objAttributes.vertices[vertIndex*3 + i];
 
-            for (int i = 0; i < 3; i++) model.meshes[meshIndex].normals[localMeshVertexCount*3 + i] = objAttributes.normals[normalIndex*3 + i];
-
             for (int i = 0; i < 2; i++) model.meshes[meshIndex].texcoords[localMeshVertexCount*2 + i] = objAttributes.texcoords[texcordIndex*2 + i];
+            if (objAttributes.normals != NULL && normalIndex != TINYOBJ_INVALID_INDEX && normalIndex >= 0)
+            {
+                for (int i = 0; i < 3; i++) model.meshes[meshIndex].normals[localMeshVertexCount*3 + i] = objAttributes.normals[normalIndex*3 + i];
+            }
+            else
+            {
+                model.meshes[meshIndex].normals[localMeshVertexCount*3 + 0] = 0.0f;
+                model.meshes[meshIndex].normals[localMeshVertexCount*3 + 1] = 1.0f;
+                model.meshes[meshIndex].normals[localMeshVertexCount*3 + 2] = 0.0f;
+            }
 
             model.meshes[meshIndex].texcoords[localMeshVertexCount*2 + 1] = 1.0f - model.meshes[meshIndex].texcoords[localMeshVertexCount*2 + 1];