Dyntopo: Performance hit when moving the viewport #76109
Labels
No Label
Interest
Alembic
Interest
Animation & Rigging
Interest
Asset Browser
Interest
Asset Browser Project Overview
Interest
Audio
Interest
Automated Testing
Interest
Blender Asset Bundle
Interest
BlendFile
Interest
Collada
Interest
Compatibility
Interest
Compositing
Interest
Core
Interest
Cycles
Interest
Dependency Graph
Interest
Development Management
Interest
EEVEE
Interest
EEVEE & Viewport
Interest
Freestyle
Interest
Geometry Nodes
Interest
Grease Pencil
Interest
ID Management
Interest
Images & Movies
Interest
Import Export
Interest
Line Art
Interest
Masking
Interest
Metal
Interest
Modeling
Interest
Modifiers
Interest
Motion Tracking
Interest
Nodes & Physics
Interest
OpenGL
Interest
Overlay
Interest
Overrides
Interest
Performance
Interest
Physics
Interest
Pipeline, Assets & IO
Interest
Platforms, Builds & Tests
Interest
Python API
Interest
Render & Cycles
Interest
Render Pipeline
Interest
Sculpt, Paint & Texture
Interest
Text Editor
Interest
Translations
Interest
Triaging
Interest
Undo
Interest
USD
Interest
User Interface
Interest
UV Editing
Interest
VFX & Video
Interest
Video Sequencer
Interest
Virtual Reality
Interest
Vulkan
Interest
Wayland
Interest
Workbench
Interest: X11
Legacy
Blender 2.8 Project
Legacy
Milestone 1: Basic, Local Asset Browser
Legacy
OpenGL Error
Meta
Good First Issue
Meta
Papercut
Meta
Retrospective
Meta
Security
Module
Animation & Rigging
Module
Core
Module
Development Management
Module
EEVEE & Viewport
Module
Grease Pencil
Module
Modeling
Module
Nodes & Physics
Module
Pipeline, Assets & IO
Module
Platforms, Builds & Tests
Module
Python API
Module
Render & Cycles
Module
Sculpt, Paint & Texture
Module
Triaging
Module
User Interface
Module
VFX & Video
Platform
FreeBSD
Platform
Linux
Platform
macOS
Platform
Windows
Priority
High
Priority
Low
Priority
Normal
Priority
Unbreak Now!
Status
Archived
Status
Confirmed
Status
Duplicate
Status
Needs Info from Developers
Status
Needs Information from User
Status
Needs Triage
Status
Resolved
Type
Bug
Type
Design
Type
Known Issue
Type
Patch
Type
Report
Type
To Do
No Milestone
No project
No Assignees
8 Participants
Notifications
Due Date
No due date set.
Dependencies
No dependencies set.
Reference: blender/blender#76109
Loading…
Reference in New Issue
No description provided.
Delete Branch "%!s(<nil>)"
Deleting a branch is permanent. Although the deleted branch may continue to exist for a short time before it actually gets removed, it CANNOT be undone in most cases. Continue?
System Information
Operating system: Win10x64
Graphics card: GTX 1080Ti
Blender Version
Broken: 2.82 - 2.90
f96a689b3b(much worse in 2.9)Worked: Unknown
Short description of error
![2020-04-26 02.13.26 Blender_ [C__Blender_Sculpt Owl_Owl.blend].png](https://archive.blender.org/developer/F8495214/2020-04-26_02.13.26_Blender___C__Blender_Sculpt_Owl_Owl.blend_.png)
When I turn dyntopo on with a high poly count model, the viewport becomes extremely slow, even if I'm not sculpting and just rotating around.
As soon as I switch dyntopo off or switch modes, it's butter smooth again. Where I'm looking also seems to have an effect on framerate.
Why should a feature related to actual sculpting affect performance when just looking around?
Dyntopo ON 2.90:
Dyntopo ON 2.82:
Dyntopo OFF 2.90:
Exact steps for others to reproduce the error
Open a high poly count model
Go to sculpt mode
Notice viewport framerate
Turn on dyntopo, nothing else
Framerate is now much lower
Turn it off and it's back to smooth
(No actual sculpting was done)
Added subscriber: @RomanKornev
Added subscriber: @ankitm
Can confirm
Added subscriber: @NelsonNAS
Is it normal to confirm without changing the bug report to "Confirmed"? LOL
Performance regression (with high density meshes, see #73360) isn't always taken as bug report. So letting someone else do it.
Since I was adding project, I thought I should add a comment too.
Added subscriber: @PabloDobarro
^^^ This is causing the perf issue I think. Without Dyntopo, no calls to the
sculpt_brush_get_geometryis made & fps is high. CPU usage is also lower .Dyntopo:
No Dyntopo:
Changed status from 'Needs Triage' to: 'Confirmed'
Added subscriber: @Vyach
Poke
Any news? Is it relative to #79146 (Sculpt mode. Performance issues after enable/disable dyntopo with zoom )
Added subscriber: @DGordillo
Hi. I can confirm I'm having issues with Dyntopo performance on the latest versions (I could sculpt 2M ~ 4M polys easily on my PC and now the same system struggles with barely 400K polys )
My system is: AMD Ryzen Threadripper 1950X 16-Core Processor, Gigabyte X399 AORUS Gaming 7 Motherboard, 32Gb RAM, NVidia GeForce GTX 1080, on Ubuntu 20.04.2 LTS
And, the exact same file has no issues when working with a Intel i7-9700, 16Gb RAM on Windows. So I'm guessing there's some optimization issues with my CPU?? It used to work well a year ago!
I can confirm this still happens for me in 3.5.1
Also on an AMD CPU on Linux. When it hangs I see a single CPU core at 100% usage, so maybe Blender is waiting for a single threaded operation here?
Notice how the cursor also becomes slow for a short while after the hiccup is triggered at 40s in the video.
Experiencing the same thing, on Arch Linux, on an AMD Ryzen 7 7735HS CPU and AMD Radeon RX 7600S GPU, on latest Blender package from official repositories of version
17:4.0.2-21.It appears that the issue is exacerbated the more I zoom out from a mesh with a sufficient lot of triangles while having Dyntopo enabled, even if all of it is in view either way. Interestingly, stuttering also grows worse if I make my viewport smaller while the same amount of mesh is visible.
Maybe it has to do something with triangles being smaller than a pixel?
It seems like that just maximizing the viewport window and then making it large enough for all visible triangles to be bigger than that perfectly mitigates this issue, but it's not a very handy workflow lol
Uploading a video demonstrating both effects with an icosphere subdivided to 327680 tris in an otherwise basically default scene. Telling perspective change from a sphere is hard, so I tried to make sure there's a camera gizmo visible to the side when demonstrating.
Strange update: if I use integrated graphics in the AMD Ryzen 7 7735HS APU (i.e. AMD Radeon 680M), even though Blender's performance is generally worse (it's a slower device in general, obviously), the performance on a complex mesh with dyntopo enabled is significantly better (~45FPS), and only about 3x slower than what I get with it disabled on this iGPU (~140FPS)
This appears to be a GPU specific bug or something?
I'm having this issue with an AMD CPU and a dedicated AMD GPU on Linux, but Roman has it with an Nvidia GPU on Windows. I don't know if this tells us anything but I think everyone with this error might be on an AMD CPU with a dedicated GPU.
This also makes me think it could be an AMD CPU specific issue.
Maybe it will be fixed by #103346 or #120304.