Maniphest T78294

Cycles Alpha (mask) broken
Closed, Archived
Actions

Assigned To
Brecht Van Lommel (brecht)
Authored By
Eugene Du (APEC)
Jun 26 2020, 9:20 AM
Tags
  • BF Blender
Subscribers
Andrew Walsh (andywalshart)
Brecht Van Lommel (brecht)
Eugene Du (APEC)
Rahul Chaudhary (RC12)

Description

System Information
Operating system: Windows-10-10.0.18362-SP0 64 Bits
Graphics card: GeForce GTX 1650 SUPER/PCIe/SSE2 NVIDIA Corporation 4.5.0 NVIDIA 446.14

Blender Version
Broken: version: 2.83.0, branch: master, commit date: 2020-06-03 14:38, hash: rB211b6c29f771

Short description of error
Material with Alpha transparency incorrect display in Cycles

Exact steps for others to reproduce the error
Cycles



Eevee

234.blend747 KBDownload

Related Objects

Event Timeline

Eugene Du (APEC) created this task.Jun 26 2020, 9:20 AM
Rahul Chaudhary (RC12) added a subscriber: Rahul Chaudhary (RC12).Jun 26 2020, 11:49 AM

This is not a bug, you have to increase the transparency light bounces for it to work correctly

Eugene Du (APEC) added a comment.Jun 26 2020, 11:52 AM

If I have more faces density I need to increase bounces, so how I need to calculate this?

Investigation here
https://blenderartists.org/t/need-help-with-mask-in-cycle/1237174

Brecht Van Lommel (brecht) closed this task as Archived.Jun 26 2020, 11:58 AM
Brecht Van Lommel (brecht) claimed this task.
Brecht Van Lommel (brecht) added a subscriber: Brecht Van Lommel (brecht).

Indeed this is not a bug.

Eugene Du (APEC) added a comment.EditedJun 26 2020, 12:05 PM

So Eevee calculate this in a seconds, and cycles need to increase bounces to the ridiculous numbers and don't even get result similar to eevee?
nice!
How to get shadows with this huge numbers for bounce?

Eugene Du (APEC) added a comment.EditedJun 26 2020, 12:23 PM

Modo example with only 1 bounce for all lights

Blender with 70 bounces


How to get shadows with this huge numbers for bounce?
Modo with 1 bounce

Blender with 70 bounces

Brecht Van Lommel (brecht) added a comment.Jun 26 2020, 12:31 PM

This bug tracker is not for user support.

You simply need more transparent bounces in this case, while other bounces can be as low as you want. The same amount of transparent bounces will be needed in any renderer, they just might not have a setting to control the maximum and have transparent bounces set to infinite.

Evan Wilson (EAW) merged a task: T80206: Dark artifacts when overlapping alpha planes in cycles.Aug 29 2020, 9:44 AM
Evan Wilson (EAW) added a subscriber: Andrew Walsh (andywalshart).