Smoke domain's wireframe visible on render


I set up smoke simulation using quick effects, use “Fire” as flow type in emitter and use emission volumetric shader using “flame” attribute as color input. The problem is that some parts of smoke domain’s are visible on render in form of small dots. It looks like wireframe reflects light somehow. Does anybody know how to get rid of this?


somke.issue.blend (510 KB)

Hm, no ideas? It looks like very fundamental issue for me, it seems strange that nobody experienced it before. Maybe my setup is incorrect somehow?

I don’t get those when I bake and render (view and regular) – it’s clean. Try blender 2.71a.

You can also 1) bake at higher resolution. 2) Add a brightness/contrast node between flame attribute and emission, and increase contrast.

I confirm - those artifacts are not visible on version 2.71. Is it some bug? Can anybody check whether you see the artifacts when rendering on 2.77?

2.77.1 - GPU render -no artefacts.
TBH, after i rendered what was in file (on frame 36) i changed Emission value to 1 and added Color Ramp between Attribute ‘flame’ and Emission nodes where i did set HSV V=0.5. This gives not overblown white on final image, otherwise most values are clipped at RGB 1 while HDR white is mostly 4.5.

Thank you for your investigation :slight_smile: Could you also check it with CPU render and no modification to the file? I just think it should render properly without the need of any workaround. Otherwise we should consider it as a bug. Is that correct? :slight_smile:

Here you go - same frame No.36, CPU render from file as it was posted.

So it looks like some issue with my configuration. Thanks a lot!

Aghh, I’ve just realized that I also don’t get those fake pixels when doing regular render from this blend file - I get them only in viewport render… But I succeeded to create new blend file which gives fake pixels with regular render as well (see attachment).

I would like to kindly ask if any of you could take this new file and do regular CPU render with blender version 2.77 and no modification to the file except doing flame simulation (it takes only a few seconds to render it). I would be really grateful because this issue is driving me crazy :slight_smile:


smoke.issue2.blend (1.46 MB)

I used to have same issue with wireframe and smoke in Blender 2.77

Have you found any work around for this problem maybe? :slight_smile:

This is odd, may be a bug – on cpu I get the artifacts, but on gpu it’s clean. Win 7 pro 64bit, Blender 2.77a, GTX 780, i5 Quad

I’ve just reported a bug:

We will see whether developers can confirm this issue.

I can not confirm any artefacts on CPU render:
3.19.0-32-generic #37~14.04.1-Ubuntu (Mint), AMD Athlon 64 X2 Dual Core 3800+
Attention! 23Mb file -

2.77 (sub 1), branch: master, commit date: 2016-06-18 20:37, hash: 7da189b, type: Release
build date: 2016-06-19, 00:04:37
platform: Linux
binary path: '/home/user/BLENDER/2.77/blender-2.77-7da189b-linux-glibc211-x86_64/blender'
build cflags:  -Wall -Wcast-align -Werror=implicit-function-declaration -Werror=return-type -Werror=vla -Wstrict-prototypes -Wmissing-prototypes -Wno-char-subscripts -Wno-unknown-pragmas -Wpointer-arith -Wunused-parameter -Wwrite-strings -Wlogical-op -Wundef -Winit-self -Wnonnull -Wmissing-include-dirs -Wno-div-by-zero -Wtype-limits -Wuninitialized -Wredundant-decls -Wno-error=unused-but-set-variable  -std=gnu99  -msse2  -msse -pipe -fPIC -funsigned-char -fno-strict-aliasing
build cxxflags:  -Wredundant-decls -Wall -Wno-invalid-offsetof -Wno-sign-compare -Wlogical-op -Winit-self -Wmissing-include-dirs -Wno-div-by-zero -Wtype-limits -Werror=return-type -Werror=implicit-function-declaration -Wno-char-subscripts -Wno-unknown-pragmas -Wpointer-arith -Wunused-parameter -Wwrite-strings -Wundef -Wuninitialized -Wundef -Wmissing-declarations   -msse2  -msse -pipe -fPIC -funsigned-char -fno-strict-aliasing
build linkflags:  -Wl,--version-script='/home/sources/buildbot-x86_64-slave/linux_glibc211_x86_64_cmake/blender.git/source/creator/'
build system: CMake


version: 3.5.1 (default, Apr 12 2016, 13:36:06) 
[GCC 4.7.1]

I had this wireframes on GPU render. I sort it out by scaling the domain so camera will not see that