Bender

The slender Blender render defender

What it does

Bender is a simple Blender render job manager for creating animation image sequences or single frames.

Bender uses python based configuration files, or profiles, to set up the render including any standard settings you'd like to apply. This means you don't need to check these are set correctly in your blend files, or have to keep updating them if you are targeting different preview or production configurations.

If a job gets interrupted, Bender recovers from the last frame rendered.

How it works

Bender is written on go

Build

go build -o ./bender cmd/bender/main.go

Run to view options

./bender

Usage:
    bender [options] 

Options:
    -j  --job        <job>         job name. (required)
    -p  --profile    <profile>     profile python file. (required)
    -b  --blend      <blend>       blend file. (required)
    -t  --target     <target>      target directory. (required)
    -s  --start      [number]      start frame. default [ 1 ]
    -e  --end        [number]      end frame. default [ 1 ]
    -l  --samples    [number]      cycles samples count. default [ 64 ]
    -r  --percent    [number]      resolution percent. default [ 100 ]
    -c  --camera     <camera>      camera name.
    -x  --executable <executable>  blender executable.

By default Bender will use the Blender executable path for MacOS. You can use the --executable option to override it.

/Applications/Blender.app/Contents/MacOS/Blender

You can set up global defaults by creating a file called .bender_defaults in your home directory. This should contain a single line with the args which will get appended.

Such as..

--target TargetDir --samples 512

These are not true defaults and doesn't yet support overrides. Coming soon.

Setting up a profile

This example template shows a 4K 2:1 aspect ratio configuration with motion blur and output to ZIP encoded EXR files. Options can be changed or removed as per your needs.

See the Blender python API documentation: https://docs.blender.org/api/current/index.html

example.py

import bpy

for scene in bpy.data.scenes:
    scene.cycles.device = "GPU"
    scene.cycles.samples = {samples}
    scene.frame_start = {start}
    scene.frame_end = {end}
    scene.frame_step = 1
    scene.render.filepath = "{outpath}"
    scene.render.resolution_x = 3840
    scene.render.resolution_y = 1920
    scene.render.resolution_percentage = {percent}
    scene.render.use_motion_blur = True
    scene.render.motion_blur_shutter = 0.5
    scene.render.use_overwrite = True
    scene.render.use_border = False
    scene.render.image_settings.file_format = "OPEN_EXR"
    scene.render.image_settings.exr_codec = "ZIP" # NONE, PXR24, ZIP, PIZ, RLE, ZIPS, B44, B44A, DWAA, DWAB
    scene.render.image_settings.color_depth = "32"
    scene.render.image_settings.color_mode='RGB'

camera_name = "{camera}"
if camera_name:
    bpy.context.scene.camera = bpy.context.scene.objects.get(camera_name)

Example job

./bender --job pants --target jobs --profile example.py --blend mypants.blend --start 1 --end 5 --samples 128

Bender will then create the following directory structure, creating the profile python file and run Blender which will create the frames in that directory.

jobs/
    pants/
         pants.py
         pants0001.exr
         pants0002.exr
         pants0003.exr
         pants0004.exr
         pants0005.exr

If a job gets interrupted, Bender recovers from the last frame rendered. If a job is complete Bender will do nothing. If you need to re-start a job simply delete off the output files and start again.

Bender parses the log output of Blender and attempts to produce a nice updating summary in your terminal. It's a bit flakey, and may break as Blender changes. But it's easier to read than Blender logs.