added missing libatomic1; adapt file hierarchy

Dockerfile

@@ -1,26 +1,27 @@
 FROM ubuntu:latest
 
-RUN apt-get update && apt-get install -y \
-    wget \
-    libxcb1 \
+RUN apt-get update && apt-get install --yes --no-install-recommends \
+    ca-certificates \
+    curl \
+    libatomic1 \
     libgl1-mesa-glx \
     libopenal1 \
-    libxrandr2 \
-    libxcursor1
+    libxcb1 \
+    libxcursor1 \
+    libxrandr2
 
-# download launcher
-RUN wget -O /tmp/ttr.tar.gz \
-    https://download.toontownrewritten.com/launcher/linux/TTRLinux-v1.2.3.tar.gz
-RUN mkdir /opt/ttr
-RUN tar -x -v --strip-components 1 -C /opt/ttr -f /tmp/ttr.tar.gz
+# ADD won't cache
+ARG LAUNCHER_VERSION=1.2.3
+RUN mkdir --parents /toontown-rewritten/launcher \
+    && curl -L https://download.toontownrewritten.com/launcher/linux/TTRLinux-v${LAUNCHER_VERSION}.tar.gz \
+        | tar -x -v --strip-components 1 -C /toontown-rewritten/launcher/
 
 RUN useradd player
-RUN usermod --shell /bin/sh player
 RUN usermod --append --groups video,audio player
-RUN chown -R player /opt/ttr
 
-RUN mkdir /engine && chown player /engine
+RUN mkdir /toontown-rewritten/engine \
+    && chown player /toontown-rewritten/engine
 USER player
-VOLUME /engine
-WORKDIR /engine
-CMD /opt/ttr/Launcher
+VOLUME /toontown-rewritten/engine
+WORKDIR /toontown-rewritten/engine
+CMD /toontown-rewritten/launcher/Launcher

launch

@@ -9,6 +9,6 @@ docker build -t ttr .
 docker run -ti \
     --env DISPLAY=$DISPLAY \
     -v /tmp/.X11-unix:/tmp/.X11-unix:ro \
-    -v toontown_rewritten_engine:/engine:rw \
+    -v toontown_rewritten_engine:/toontown-rewritten/engine:rw \
     --env QT_X11_NO_MITSHM=1 \
     ttr