Add the base image for 18.04

ci/Dockerfile.Ubuntu.18.04

@@ -0,0 +1,100 @@
+# Taichi Dockerfile for development
+FROM nvidia/cudagl:11.2.2-devel-ubuntu18.04
+# Use 11.2 instead of 11.4 to avoid forward compatibility issue on Nvidia driver 460
+
+ENV NVIDIA_DRIVER_CAPABILITIES compute,graphics,utility
+ENV DEBIAN_FRONTEND=noninteractive
+LABEL maintainer="https://github.com/taichi-dev"
+
+RUN apt-get update && \
+    apt-get install -y software-properties-common \
+                       python3-pip \
+                       libtinfo-dev \
+                       clang-10 \
+                       wget \
+                       git \
+                       unzip \
+                       libxrandr-dev \
+                       libxinerama-dev \
+                       libxcursor-dev \
+                       libxi-dev \
+                       libglu1-mesa-dev \
+                       freeglut3-dev \
+                       mesa-common-dev \
+                       libssl-dev \
+                       libglm-dev \
+                       libxcb-keysyms1-dev \
+                       libxcb-dri3-dev \
+                       libxcb-randr0-dev \
+                       libxcb-ewmh-dev \
+                       libpng-dev \
+                       g++-multilib \
+                       libmirclient-dev \
+                       libwayland-dev \
+                       bison \
+                       libx11-xcb-dev \
+                       liblz4-dev \
+                       libzstd-dev \
+                       qt5-default \
+                       libglfw3 \
+                       libglfw3-dev \
+                       libjpeg-dev \
+                       libvulkan-dev
+
+# Install the latest version of CMAKE v3.20.5 from source
+WORKDIR /
+RUN wget https://github.com/Kitware/CMake/releases/download/v3.20.5/cmake-3.20.5-linux-x86_64.tar.gz
+RUN tar xf cmake-3.20.5-linux-x86_64.tar.gz && \
+    rm cmake-3.20.5-linux-x86_64.tar.gz
+ENV PATH="/cmake-3.20.5-linux-x86_64/bin:$PATH"
+
+# Intall LLVM 10
+WORKDIR /
+# Make sure this URL gets updated each time there is a new prebuilt bin release
+RUN wget https://github.com/taichi-dev/taichi_assets/releases/download/llvm10_linux_patch2/taichi-llvm-10.0.0-linux.zip
+RUN unzip taichi-llvm-10.0.0-linux.zip && \
+    rm taichi-llvm-10.0.0-linux.zip
+ENV PATH="/taichi-llvm-10.0.0-linux/bin:$PATH"
+# Use Clang as the default compiler
+ENV CC="clang-10"
+ENV CXX="clang++-10"
+
+# Setting up Vulkan SDK
+# References
+# [1] https://github.com/edowson/docker-nvidia-vulkan
+# [2] https://gitlab.com/nvidia/container-images/vulkan/-/tree/master/docker
+WORKDIR /vulkan
+RUN wget https://sdk.lunarg.com/sdk/download/1.2.189.0/linux/vulkansdk-linux-x86_64-1.2.189.0.tar.gz
+RUN tar xf vulkansdk-linux-x86_64-1.2.189.0.tar.gz && \
+    rm vulkansdk-linux-x86_64-1.2.189.0.tar.gz
+# Locate Vulkan components
+ENV VULKAN_SDK="/vulkan/1.2.189.0/x86_64"
+ENV PATH="$VULKAN_SDK/bin:$PATH"
+ENV LD_LIBRARY_PATH="$VULKAN_SDK/lib${LD_LIBRARY_PATH:+:$LD_LIBRARY_PATH}"
+ENV VK_LAYER_PATH="$VULKAN_SDK/etc/vulkan/explicit_layer.d"
+WORKDIR /usr/share/vulkan/icd.d
+COPY ci/vulkan/icd.d/nvidia_icd.json nvidia_icd.json
+
+# Create non-root user for running the container
+RUN useradd -ms /bin/bash dev
+WORKDIR /home/dev
+USER dev
+
+# Install miniconda
+RUN wget https://repo.anaconda.com/miniconda/Miniconda3-latest-Linux-x86_64.sh && \
+    bash Miniconda3-latest-Linux-x86_64.sh -p /home/dev/miniconda -b
+ENV PATH="/home/dev/miniconda/bin:$PATH"
+
+# Set up multi-python environment
+RUN conda init bash
+RUN conda create -n py36 python=3.6 -y
+RUN conda create -n py37 python=3.7 -y
+RUN conda create -n py38 python=3.8 -y
+RUN conda create -n py39 python=3.9 -y
+
+# Load scripts for build and test
+WORKDIR /home/dev/scripts
+COPY ci/scripts/ubuntu_build_test.sh ubuntu_build_test.sh
+
+WORKDIR /home/dev
+ENV LANG="C.UTF-8"

ci/Dockerfile.Ubuntu.20.04

@@ -6,7 +6,6 @@ ENV NVIDIA_DRIVER_CAPABILITIES compute,graphics,utility
 ENV DEBIAN_FRONTEND=noninteractive
 LABEL maintainer="https://github.com/taichi-dev"
 
-# Ubuntu 20.04 installs Python 3.8 by default
 RUN apt-get update && \
     apt-get install -y software-properties-common \
                        python3-pip \