Maniphest T76130

Not possible to render smoke simulation in created view layer
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Assigned To
Richard Antalik (ISS)
Authored By
Wilbur Jaywright (zargulthewizard)
Apr 26 2020, 8:54 PM
Tags
  • BF Blender
  • Nodes & Physics
Subscribers
Alaska (Alaska)
Jacques Lucke (JacquesLucke)
Richard Antalik (ISS)
Wilbur Jaywright (zargulthewizard)

Description

System Information
Operating system: Windows 10 64 bit
Graphics card: Intel HD Graphics

Blender Version
Broken: 2.83 beta, hash blender-2.83-13e3a1c53222-windows64

Short description of error
I am trying to use smoke or fire for a heat wave effect, but when I've changed what layer the smoke domain is visible on, it malfunctioned and showed a black "shadow" when rendering, like Sauron in The Hobbit movie. After changing the material from the default principled volume to a simple emission shader with its strength driven by the "temperature" attribute, it no longer shows up at all in the second render layer. I have a blend file here that has the domain in both layers. "Render Image," and a split view should show up in the compositor.

Steps to reproduce

T76130.blend723 KBDownload

  1. Open file
  2. Render

Smoke is not visible

Event Timeline

Wilbur Jaywright (zargulthewizard) created this task.Apr 26 2020, 8:54 PM
Richard Antalik (ISS) renamed this task from Smoke and fire simulations do not show up properly when moved to other render layers to Not possible to render smoke simulation in created view layer.Apr 28 2020, 9:20 PM
Richard Antalik (ISS) changed the task status from Needs Triage to Confirmed.
Richard Antalik (ISS) updated the task description.
Richard Antalik (ISS) added a project: Nodes & Physics.
Jacques Lucke (JacquesLucke) changed the task status from Confirmed to Needs Information from User.May 11 2020, 5:57 PM
Jacques Lucke (JacquesLucke) added a subscriber: Jacques Lucke (JacquesLucke).

When I open the file, rebake the simulation and then render, I get this:

So I'm not sure how to reproduce the issue. Please provide more specific steps.

Wilbur Jaywright (zargulthewizard) added a comment.May 11 2020, 6:03 PM

This is not my file, so I'm not sure what the deal is there. But I do know that my file does not split the two layers in the render output. Only the spit viewer in the compositor shows the problem.

Wilbur Jaywright (zargulthewizard) added a comment.EditedMay 11 2020, 6:26 PM

To reproduce:

  • In blender 2.83 beta, hash 13e3a1c53222 for Windows 64 bit, make sure the default cube is selected.
  • Call a "Quick Smoke" effect on the cube.
  • Change the operator setting to "Fire."
  • Play the simulation a bit. It will work correctly. Stop and rewind to frame 1.
  • Change the cache type to "Final" so it can be baked, then bake the simulation.
  • Play the simulation, it will work correctly. Stop it at a point where there is fire in the air (I'm at frame 34).
  • Create a new View Layer, the tooltip python operation for this button is "bpy.ops.scene.view_layer_add()"
  • Switch back to the original View Layer.
  • Switch to the Compositing tab.
  • Check "Use nodes."
  • Add the new "View Layer.001" as an input in the compositor.
  • Add a split viewer node, and connect the two layers to it.
  • Render Image. The compositor will show the correct result.
  • Go ahead and click "Fit" to show the whole view output in the compositor.
  • Switch to the new "View Layer.001"
  • In the layout tab, add a new collection, and put the smoke domain in it.
  • Uncheck the original "Collection 1" so that it will not appear in "View layer.001"
  • Switch back to the original "View Layer"
  • Switch back to the compositor.
  • Render Image.
  • The side of the split viewer that shows the second view layer will show no cube (correct) and a dark shadow instead of fire (incorrect).
Wilbur Jaywright (zargulthewizard) added a comment.EditedMay 11 2020, 6:49 PM

CONTINUED:

  • After the above, go to the Shading tab.
  • Select and delete the Principled Volume node from the "Smoke Domain Material"
  • Add->Input->Attribute
  • Assign "temperature" to the Attribute node.
  • Add->Shader->Emission
  • Connect the temperature Factor output from Attribute to Strength input on Emission, then connect Emission output to Volume on Material Output.
  • Switch back to Compositing
  • Render Image.
  • The split view will show the cube (if you can discern it, it's hidden behind the following) and a bright white plume for View Layer (correct), but nothing, not even the Sauron mist, for View Layer.001 (incorrect).
Campbell Barton (campbellbarton) changed the task status from Needs Information from User to Needs Information from Developers.May 20 2020, 7:54 AM
Alaska (Alaska) added a subscriber: Alaska (Alaska).EditedMay 20 2020, 8:10 AM

I am able to reproduce the issue following the steps described in T76130#929028 on:

Linux-5.4.0-7626-generic-x86_64-with-debian-bullseye
GTX 1050Ti
Blender version: 2.83 rBdfe8195dfe83 (2020-05-19 23:15)

One step had to be added though. The smoke domain needs it's "Blackbody Intensity" turned up in the shader editor.

Alaska (Alaska) added a comment.May 20 2020, 8:15 AM

Can also reproduce the issue following the steps in T76130#929043 with the same setup.

The issue being described is that the "Temperature" attribute of the smoke domain does not appear to have an impact on the material shader if the view layer the domain is on has the emitter of the fire in a disabled collection. Even if the simulation has been baked.

Richard Antalik (ISS) closed this task as Resolved.Nov 26 2020, 7:37 PM
Richard Antalik (ISS) claimed this task.
Richard Antalik (ISS) added a subscriber: Richard Antalik (ISS).

I can reproduce this issue in 2.83, but not in latest 2.92 build, so I will close this as resolved.