Merge commit '13.0-RC1~2'

os/emscripten/Dockerfile

@@ -1,4 +1,4 @@
-FROM emscripten/emsdk:2.0.34
+FROM emscripten/emsdk:3.1.28
 
 COPY emsdk-liblzma.patch /
 RUN cd /emsdk/upstream/emscripten && patch -p1 < /emsdk-liblzma.patch

os/emscripten/README.md

@@ -1,23 +1,38 @@
 ## How to build with Emscripten
 
-Building with Emscripten works with emsdk 3.0.0 and above.
-
-You will also need libharfbuzz-dev and libicu-dev installed on your host OS.
-
+Please use docker with the supplied `Dockerfile` to build for emscripten.
+It takes care of a few things:
+- Use a version of emscripten we know works
+- Patch in LibLZMA support (as this is not supported by upstream)
 
+First, build the docker image by navigating in the folder this `README.md` is in, and executing:
 ```
-  sudo apt-get install autoconf automake libtool gperf libharfbuzz-dev libicu-dev libfreetype-dev
-
-  ./emscripten-build.sh
+  docker build -t emsdk-lzma .
 ```
 
-And now you have in your build folder files like "openttd.html".
+Next, navigate back to the root folder of this project.
 
-To run it locally, you would have to start a local webserver, like:
+Now we build the host tools first:
+```
+  mkdir build-host
+  docker run -it --rm -v $(pwd):$(pwd) -u $(id -u):$(id -g) --workdir $(pwd)/build-host emsdk-lzma cmake .. -DOPTION_TOOLS_ONLY=ON
+  docker run -it --rm -v $(pwd):$(pwd) -u $(id -u):$(id -g) --workdir $(pwd)/build-host emsdk-lzma make -j$(nproc) tools
+```
+
+Finally, we build the actual game:
+```
+  mkdir build
+  docker run -it --rm -v $(pwd):$(pwd) -u $(id -u):$(id -g) --workdir $(pwd)/build emsdk-lzma emcmake cmake .. -DHOST_BINARY_DIR=../build-host -DCMAKE_BUILD_TYPE=Release -DOPTION_USE_ASSERTS=OFF
+  docker run -it --rm -v $(pwd):$(pwd) -u $(id -u):$(id -g) --workdir $(pwd)/build emsdk-lzma emmake make -j$(nproc)
+```
+
+In the `build` folder you will now see `openttd.html`.
+
+To run it locally, you would have to start a local webserver; something like:
 
 ```
   cd build
   python3 -m http.server
 ````
 
-Now you can play the game via http://127.0.0.1:8000/openttd.html .
+You can now play the game via http://127.0.0.1:8000/openttd.html .