Maniphest T96874

New haircurves brush adds them with zero radius, radius not taken into account by Eevee (when rendered as strips)
Closed, Archived
Actions

Assigned To
None
Authored By
Vyacheslav (hitrpr)
Mar 30 2022, 2:28 AM
Tags
  • BF Blender
  • EEVEE & Viewport
  • Nodes & Physics
Subscribers
Alaska (Alaska)
Dalai Felinto (dfelinto)
Hans Goudey (HooglyBoogly)
Jacques Lucke (JacquesLucke)
Philipp Oeser (lichtwerk)
Richard Antalik (ISS)
Vyacheslav (hitrpr)

Description

System Information
Operating system: Windows-8.1-6.3.9600-SP0 64 Bits
Graphics card: NVIDIA GeForce GTX 660 Ti/PCIe/SSE2 NVIDIA Corporation 4.5.0 NVIDIA 472.12

Blender Version
Broken: version: 3.2.0 Alpha, branch: master, commit date: 2022-03-28 21:29, hash: rB27424b758a87

Short description of error
Drivers are fresh (tried with old too). I can see hairs only in Cycles, only with default domain, but i can`t see hairs, that I add to

T96874.blend874 KBDownload

  1. Open file
  2. Switch to rendered shading
  3. Delete all hair
  4. Add new hair

New hair will not be visible

Related Objects

Event Timeline

Vyacheslav (hitrpr) created this task.Mar 30 2022, 2:28 AM
Alaska (Alaska) added a subscriber: Alaska (Alaska).Mar 30 2022, 4:09 AM

I assume the hair isn't displaying when you add it again because the hair has 0 as it's radius. Meaning it is infinitely thin. How do you change the radius? I don't know.

As for the hair not being visible in the workbench, that's probably a bug. I can see the hair in the work bench.

Richard Antalik (ISS) changed the task status from Needs Triage to Confirmed.Mar 30 2022, 4:16 AM
Richard Antalik (ISS) updated the task description.
Richard Antalik (ISS) added a project: Render & Cycles.
Richard Antalik (ISS) updated the task description.Mar 30 2022, 4:18 AM
Richard Antalik (ISS) edited projects, added Modeling; removed Render & Cycles.Mar 30 2022, 4:23 AM
Richard Antalik (ISS) added a subscriber: Richard Antalik (ISS).

@Alaska (Alaska) Hmm it's probably as you say, even if you don't remove existing hair, new is not visible. So will change tag to modeling instead. I don't see any hair radius setting for brush.

Hans Goudey (HooglyBoogly) edited projects, added EEVEE & Viewport; removed Modeling.Mar 30 2022, 5:17 AM
Hans Goudey (HooglyBoogly) added a subscriber: Hans Goudey (HooglyBoogly).

Yeah, there's no way to edit the radius yet. This stuff is all actively in development and not really ready for use yet.
So that part isn't really a bug. One important patch to follow is D14277.

I does seem there's a problem with the new object not being displayed in the viewport though, I'm not sure about that.

Philipp Oeser (lichtwerk) added a project: Nodes & Physics.Apr 6 2022, 2:54 PM
Philipp Oeser (lichtwerk) added a subscriber: Philipp Oeser (lichtwerk).

Yeah, it is the radius.

Quickie to change with python:

import bpy
C = bpy.context

radius = C.active_object.data.attributes['radius']
for dat in radius.data:
    dat.value = 0.05
  • Workbench does not take hair shape into account (also shouldnt I think, also didnt do this in the old particle hair)
  • Eevee did this in the old particle hair (but only if the shape was set to Strip and only using the "old" settings in particle hair Diameter Root and Diameter Tip)
Philipp Oeser (lichtwerk) added a subscriber: Jacques Lucke (JacquesLucke).Apr 6 2022, 3:01 PM

So actually the issue is twofold:

  • [1] The brush that adds curves adds them with zero radius
  • [2] Eevee does not take the radius into account when displaying the hair as Strip

I actually think this should be two separate TODOs.
reg. [1] : @Jacques Lucke (JacquesLucke) , would it make sense to

  • add an option Interpolate Radius to the brush? (or just silently do it when using Interpolate Shape?)
  • when not using interpolation, maybe it would make sense to add them with something close to the old particle hair: this had 1cm at the root and 0cm at the tip
Philipp Oeser (lichtwerk) renamed this task from invisible new hair/curve type to New haircurves brush adds them with zero radius, radius not taken into account by Eevee (when rendered as strips).Apr 6 2022, 3:02 PM
Hans Goudey (HooglyBoogly) added a comment.Apr 6 2022, 4:57 PM

Regarding the two todos, I think that mostly makes sense, though I'd probably combine the setting for radius interpolation with the interpolation of all generic attributes.

EEVEE/workbench rendering of the new curves object basically needs to be rewritten, there is already a todo for that here: T96455

Dalai Felinto (dfelinto) closed this task as Archived.May 9 2022, 3:07 PM
Dalai Felinto (dfelinto) added a subscriber: Dalai Felinto (dfelinto).

This is in development still. Archiving it for now.