Page MenuHome
Create Task
Maniphest T69303

Blender 2.8 - Rendered result biased/masked by texture alpha
Closed, ArchivedPublic
Actions

Description

System Information
Operating system: Linux-4.15.0-58-generic-x86_64-with-debian-buster-sid 64 Bits
Graphics card: GeForce GTX 1070 Ti/PCIe/SSE2 NVIDIA Corporation 4.5.0 NVIDIA 430.40

Blender Version
Broken: version: 2.80 (sub 75), branch: master, commit date: 2019-07-29 14:47, hash: rBf6cb5f54494e

Short description of error
Rendered result is masked by alpha, but if we connect alpha to a dummy Math node result is not masked anymore!

Exact steps for others to reproduce the error

  1. Open blend file:

wong_image_color.blend1 MBDownload

  1. Switch to rendered mode.
  2. Connect image texture node Alpha output to "Add" node (any input will do).
  3. Observe rendered result getting masked/unmasked by alpha channel.

Event Timeline

Simon (notallowed) created this task.Aug 29 2019, 4:46 PM
Simon (notallowed) updated the task description. (Show Details)
Simon (notallowed) updated the task description. (Show Details)
Brecht Van Lommel (brecht) changed the task status from Unknown Status to Unknown Status.Aug 29 2019, 5:01 PM
Brecht Van Lommel (brecht) claimed this task.
Brecht Van Lommel (brecht) added a subscriber: Brecht Van Lommel (brecht).

This is confusing but it works this way by design currently. If the alpha socket is used then alpha is removed from the color. We plan to improve this, but it's not considered a bug currently.

Simon (notallowed) added a comment.EditedAug 30 2019, 8:15 AM

Well I thought so, after a bit of studying, I found a workaround for this. I'm using Channel Packed alpha now, which in fact is proper choice for my needs (replicating game engine renderer).