Black render artifact with CPU+GPU rendering in viewport
Open, ConfirmedPublic


System Information
Windows 7 Pro
Nvidia Quadro P6000
Intel Xeon E5-2690 v4

Blender Version
Broken: daily builds 2.79 since at least 25.10.2017.
Worked: -

Short description of error
If I enable combined CPU+GPU rendering, a black rectangle shows up on one of my objects. It shows up in viewport rendering, and also in the final render. This seems to be independent of the material used. I have provided a stripped down version of the scene where it is still visible. This time only in the viewport, the final render works for this simplified scene.

The artifact seems to be "locked in space", I can move or rotate the object away, so that it disappears. In some rotation angles it is not a black rectangle, but dense black lines.
What is also interesting is that the surface of the object in not only black, but partly transparent. I have put a lamp and a cube inside the object in the demo scene, these should not be visible from outside, but they are.

Exact steps for others to reproduce the error

  • Open file. In the render settings GPU compute should be turned on, and in the user preferences CUDA should have both the CPU and GPU selected.
  • Turn on viewport rendering. --> black box visible.
  • Then switch to CPU rendering. No more black box.



Related Objects

Here, problem appears with GPU only too.

If origin of the object is moved to center of geometry, problem is solved.

It looks like a duplicate bugreport of this T4835 that became a ToDo.

Brecht Van Lommel (brecht) triaged this task as Confirmed priority.Nov 22 2017, 12:43 AM

Confirmed the artifacts, needs some investigation to figure out if this is a to do or new unknown case.