Cycles: Fix wrong shading when some mesh triangle has non-finite coordinate

This is fully unpredictable for artists when one damaged object makes the whole
scene to render incorrectly. This involves two main changes:

- It is not enough to check triangle bounds to be valid when building BVH.
  This is because triangle might have some finite vertices and some non-finite.

- We shouldn't add non-finite triangle area to the overall area for MIS.

1 files changed, 2 insertions, 0 deletions

diff --git a/intern/cycles/render/mesh.h b/intern/cycles/render/mesh.h
index 3483ab4fd69..ed7cb881e91 100644
--- a/intern/cycles/render/mesh.h
+++ b/intern/cycles/render/mesh.h
@@ -72,6 +72,8 @@ public:
 		                    float3 r_verts[3]) const;
 
 		float3 compute_normal(const float3 *verts) const;
+
+		bool valid(const float3 *verts) const;
 	};
 
 	Triangle get_triangle(size_t i) const