Faceted geometry in Cycles along edges of shadows #69030

New Issue

Joe Williamsen · 2019-08-22T04:15:02+02:00

Joe Williamsen commented

2019-08-22 04:15:02 +02:00

System Information
Operating system: Windows-7-6.1.7601-SP1 64 Bits
Graphics card: GeForce RTX 2070/PCIe/SSE2 NVIDIA Corporation 4.5.0 NVIDIA 431.60

Blender Version
Broken: version: 2.80 (sub 75), branch: master, commit date: 2019-07-29 14:47, hash: f6cb5f5449
Worked: (optional)

Short description of error
Geometry can appear very "faceted" at the extreme edges of curved geometry - where the angle of the normal approaches perpendicular to the light.

I've been seeing this for a while, so, it might be a known issue. I spent a few hours trying different ways to eliminate this, and while using Adaptive Subdivision will work, it isn't ideal on meshes where subdivisions will affect the shape too dramatically.

I ran into a similar problem a while back using Redshift - they believed it to be related to their shadow bias algorithm ( https://www.redshift3d.com/forums/viewthread/8035/#51073 ) - and eventually, they dialed it in to where I never saw it again.

Exact steps for others to reproduce the error

Open the attached .blend file. Render using Cycles.

Faceted Geometry Bug.zip

**System Information** Operating system: Windows-7-6.1.7601-SP1 64 Bits Graphics card: GeForce RTX 2070/PCIe/SSE2 NVIDIA Corporation 4.5.0 NVIDIA 431.60 **Blender Version** Broken: version: 2.80 (sub 75), branch: master, commit date: 2019-07-29 14:47, hash: `f6cb5f5449` Worked: (optional) **Short description of error** Geometry can appear very "faceted" at the extreme edges of curved geometry - where the angle of the normal approaches perpendicular to the light. ![faceted geometry.jpg](https://archive.blender.org/developer/F7684400/faceted_geometry.jpg) I've been seeing this for a while, so, it might be a known issue. I spent a few hours trying different ways to eliminate this, and while using Adaptive Subdivision will work, it isn't ideal on meshes where subdivisions will affect the shape too dramatically. I ran into a similar problem a while back using Redshift - they believed it to be related to their shadow bias algorithm ( https://www.redshift3d.com/forums/viewthread/8035/#51073 ) - and eventually, they dialed it in to where I never saw it again. **Exact steps for others to reproduce the error** Open the attached .blend file. Render using Cycles. [Faceted Geometry Bug.zip](https://archive.blender.org/developer/F7684402/Faceted_Geometry_Bug.zip)

Joe Williamsen commented

2019-08-22 04:15:02 +02:00

Added subscriber: @Joe_W