Using GR3 with Docker

If you install the Julia or Python packages for GR or download the pre-built Linux binaries within a Docker container, you will be able to use the non-interactive output formats like PNG images or SVG files.

GR3 however requires X11 and OpenGL libraries to be installed and a connection to an X server to exist, which will usually not be the case inside a Docker container. To be able to use GR3 as well, you will need to install the X11 and OpenGL dependencies listed on the Julia, Python or C page and run Xvfb or a similar tool to start an X server that can then be used by GR3.

The following example shows how to use GR3 from within an official Julia or Python Docker container:

% docker run -it python:stretch bash

# Install X11, OpenGL and Xvfb
$ apt update -y
$ apt install -y libxt6 libxrender1 libxext6 libgl1-mesa-glx xvfb

# Set GKS_WSTYPE to output to PNG images
$ export GKS_WSTYPE=png

# Install the Python Package gr
$ pip3 install gr

# Run Python within an Xvfb session
$ xvfb-run --server-args '-screen 0 1920x1080x24' python3
>>> import gr3
>>> # GR3 will use software rendering, e.g. using llvmpipe
>>> gr3.getrenderpathstring()
[...] 3.0 Mesa 13.0.6 - Gallium 0.4 on llvmpipe (LLVM 3.9, 256 bits) [...]

% docker run -it julia:stretch bash

# Install X11, OpenGL and Xvfb
$ apt update -y
$ apt install -y libxt6 libxrender1 libxext6 libgl1-mesa-glx xvfb

# Set GKS_WSTYPE to output to PNG images
$ export GKS_WSTYPE=png

# Install the Julia Package GR
$ julia
julia> using Pkg
julia> Pkg.add("GR")

# Run Julia within an Xvfb session
$ xvfb-run --server-args '-screen 0 1920x1080x24' julia
julia> using GR
julia> # GR3 will use software rendering, e.g. using llvmpipe
julia> gr3.getrenderpathstring()
[...] 3.0 Mesa 13.0.6 - Gallium 0.4 on llvmpipe (LLVM 3.9, 256 bits) [...]