I use a node group (see linked blend files) along with extremely limited numbers of bounces & lighting to achieve a certain non-photorealistic effect in cycles. This effect has previously resulted in renders that have zero noise and only solid blocks of color. However, any file I create with blender version 2.8 (see version output below) results in noise when using identical settings to the files created in pre-2.8. The pre-2.8 files perform as expected when rendered in 2.8. I suspect that there may be some setting that was set in 2.7 that isn't being set in 2.8's file initialization but I'm unsure how to confirm or deny that.
$ blender --version Blender 2.80 (sub 75) build date: 2019-07-30 build time: 16:57:38 build commit date: 2019-07-29 build commit time: 14:47 build hash: f6cb5f54494e build platform: Linux build type: Release build c flags: -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 -Wformat-signedness -Wrestrict -Wuninitialized -Wredundant-decls -Wshadow -Wno-error=unused-but-set-variable -Wimplicit-fallthrough=5 -march=x86-64 -mtune=generic -O2 -pipe -fno-plt -fuse-ld=gold -fopenmp -std=gnu11 -msse -pipe -fPIC -funsigned-char -fno-strict-aliasing -msse2 build c++ flags: -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 -Wformat-signedness -Wrestrict -Wuninitialized -Wundef -Wmissing-declarations -Wimplicit-fallthrough=5 -march=x86-64 -mtune=generic -O2 -pipe -fno-plt -fuse-ld=gold -fopenmp -std=c++11 -msse -pipe -fPIC -funsigned-char -fno-strict-aliasing -msse2 build link flags: -Wl,--version-script='/build/blender/src/blender-2.80/source/creator/blender.map' build system: CMake
The difference is very minor, but is there, as demonstrated by using a flood fill with a threshold of 0 via GIMP on various parts of each image:
My system information (generated with
System: Host: ganymede Kernel: 4.19.66-1-MANJARO x86_64 bits: 64 Desktop: KDE Plasma 5.16.4 Distro: Manjaro Linux Machine: Type: Desktop Mobo: Micro-Star model: X470 GAMING PLUS (MS-7B79) v: 2.0 serial: <root required> UEFI [Legacy]: American Megatrends v: A.B0 date: 07/04/2019 CPU: 8-Core: AMD Ryzen 7 2700X type: MT MCP speed: 2160 MHz min/max: 2200/3700 MHz Graphics: Device-1: Advanced Micro Devices [AMD/ATI] Ellesmere [Radeon RX 470/480/570/570X/580/580X/590] driver: amdgpu v: kernel Display: x11 server: X.Org 1.20.5 driver: amdgpu FAILED: ati unloaded: modesetting resolution: 1920x1080~60Hz, 1920x1080~60Hz OpenGL: renderer: Radeon RX 580 Series (POLARIS10 DRM 3.27.0 4.19.66-1-MANJARO LLVM 8.0.1) v: 4.5 Mesa 19.1.4 Network: Device-1: Realtek RTL8111/8168/8411 PCI Express Gigabit Ethernet driver: r8168 Drives: Local Storage: total: 1.84 TiB used: 818.81 GiB (43.4%) Info: Processes: 481 Uptime: 2d 1h 55m Memory: 31.42 GiB used: 16.30 GiB (51.9%) Shell: bash inxi: 3.0.35
It appears that this pixelated noise is happening regardless of what material I use. A simple node group of a noise texture fed through a colorramp on constant going to an emission shader, assigned to a flat plane demonstrates this very effectively. I've increased the contrast to highlight the noise in the midtone regions, though this has crushed out the noise in the black and white regions..
This has happened in PNG, JPEG, Targa, and TIFF export formats.