Cycles renders missing/semitransparent faces on Tails OS #51051

New Issue

Hank · 2017-03-26T05:55:38+02:00

Hank commented

2017-03-26 05:55:38 +02:00

I'm running Blender 2.78c on Tails 2.11. When rendering using Cycles, the faces on some models appear transparent at best, and completely missing at worst.

The affected faces are mostly in flat areas of the model, where many faces that share the same normal are next to each other. Curved areas do not seem to be affected. This happens both using the "Rendered" viewport mode and in the final render, but other viewport modes (solid, textured, material) work fine.

I've tested this on two computers, both with Nvidia graphics cards. Both of them have the issue in Tails, but not when using Ubuntu or Windows, so I don't think it's a hardware issue.

Steps to reproduce:

Download Tails from the website and follow the instructions to install it onto a USB drive.
Boot Tails.
Download the 32-bit Blender .tar.gz distribution in Tails, extract it, and start it.
From the starting scene, select the cube, and enter edit mode.
Subdivide all faces of the cube by 10, to better show the effect. Exit edit mode.
(Optional) From the materials tab, edit the diffuse color to make the cube easier to see.
Switch to the Cycles renderer, and change the 3d viewport mode to "Rendered". Despite the cube having the default diffuse shader, some of the faces should be transparent or missing.

Example of an improperly rendered model:

I'm running Blender 2.78c on [Tails](https://tails.boum.org/) 2.11. When rendering using Cycles, the faces on some models appear transparent at best, and completely missing at worst. The affected faces are mostly in flat areas of the model, where many faces that share the same normal are next to each other. Curved areas do not seem to be affected. This happens both using the "Rendered" viewport mode and in the final render, but other viewport modes (solid, textured, material) work fine. I've tested this on two computers, both with Nvidia graphics cards. Both of them have the issue in Tails, but not when using Ubuntu or Windows, so I don't think it's a hardware issue. Steps to reproduce: 1. Download Tails from the website and follow the instructions to install it onto a USB drive. 2. Boot Tails. 3. Download the 32-bit Blender .tar.gz distribution in Tails, extract it, and start it. 4. From the starting scene, select the cube, and enter edit mode. 5. Subdivide all faces of the cube by 10, to better show the effect. Exit edit mode. 6. (Optional) From the materials tab, edit the diffuse color to make the cube easier to see. 7. Switch to the Cycles renderer, and change the 3d viewport mode to "Rendered". Despite the cube having the default diffuse shader, some of the faces should be transparent or missing. Example of an improperly rendered model: ![Screenshot from 2017-03-26 03_42_20.png](https://archive.blender.org/developer/F523106/Screenshot_from_2017-03-26_03_42_20.png)

Hank commented

2017-03-26 05:55:38 +02:00

Changed status to: 'Open'