From 7a35a0f4196bc2ece323c24cdecaba568555eb4d Mon Sep 17 00:00:00 2001 From: Stefan Werner Date: Mon, 23 May 2016 13:27:46 +0200 Subject: [PATCH] Fixed a rare case of NaN in Cycles This fixes a rare case where NaNs could exist inside Cycles. When certain invalid meshes were passed in, Cycles would try too normalize a zero length normal during its setup stage. While it does check against division by zero, it still returns a zero length normal and passes it on to the path tracing kernel. The kernel then operates under the assumption that normals are valid, and in the case of such a zero length normal, would eventually create NaNs that propagate through and result in black pixels. Reviewers: #cycles Subscribers: brecht, sergey Projects: #cycles Differential Revision: https://developer.blender.org/D2008 --- intern/cycles/render/mesh.cpp | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/intern/cycles/render/mesh.cpp b/intern/cycles/render/mesh.cpp index de1533c26af..d26404035eb 100644 --- a/intern/cycles/render/mesh.cpp +++ b/intern/cycles/render/mesh.cpp @@ -285,7 +285,7 @@ static float3 compute_face_normal(const Mesh::Triangle& t, float3 *verts) float normlen = len(norm); if(normlen == 0.0f) - return make_float3(0.0f, 0.0f, 0.0f); + return make_float3(1.0f, 0.0f, 0.0f); return norm / normlen; }