1578 Add WASM support

[reneSchm]

Changes and Information

Please briefly list the changes (main added features, changed items, or corrected bugs) made:

• Small changes to enable the pyodide/emscripten toolchain

If need be, add additional information and what the reviewer should look out for in particular:

• See comment below for instructions

Merge Request - Guideline Checklist

Please check our git workflow. Use the draft feature if the Pull Request is not yet ready to review.

Checks by code author

• Every addressed issue is linked (use the "Closes #ISSUE" keyword below).
• New code adheres to coding guidelines.
• No large data files have been added (files should in sum not exceed 100 KB, avoid PDFs, Word docs, etc.).
• Tests are added for new functionality and a local test run was successful (with and without OpenMP).
• Appropriate documentation within the code (Doxygen) for new functionality has been added in the code.
• Appropriate external documentation (ReadTheDocs) for new functionality has been added to the online documentation and checked in the preview.
• Proper attention to licenses, especially no new third-party software with conflicting license has been added.
• (For ABM development) Checked benchmark results and ran and posted a local test above from before and after development to ensure performance is monitored.

Checks by code reviewer(s)

• Corresponding issue(s) is/are linked and addressed.
• Code is clean of development artifacts (no deactivated or commented code lines, no debugging printouts, etc.).
• Appropriate unit tests have been added, CI passes, code coverage and performance is acceptable (did not decrease).
• No large data files added in the whole history of commits(files should in sum not exceed 100 KB, avoid PDFs, Word docs, etc.).
• On merge, add 2-5 lines with the changes (main added features, changed items, or corrected bugs) to the merge-commit-message. This can be taken from the briefly-list-the-changes above (best case) or the separate commit messages (worst case).

[reneSchm]

Read all steps first, not everything is stated in order.

Get git, cmake, make, python. Create and load python venv.

Sources:

• https://developer.mozilla.org/en-US/docs/WebAssembly/Guides/C_to_Wasm
• https://emscripten.org/docs/getting_started/downloads.html
• https://stackoverflow.com/questions/75594285/emscripten-in-cmake-doesnt-output-html-file-when-i-setcmake-executable-suffix
• https://pyodide-build.readthedocs.io/en/latest/tutorials/quickstart.html#
• https://docs.marimo.io/guides/wasm/#packages

Direct WASM builds

1. Set up emscripten SDK:

   # Get the emsdk repo
   git clone https://github.com/emscripten-core/emsdk.git
   
   # Enter that directory
   cd emsdk
   
   # Fetch the latest version of the emsdk (not needed the first time you clone)
   git pull
   
   # Download and install the latest SDK tools.
   ./emsdk install latest
   
   # Make the "latest" SDK "active" for the current user. (writes .emscripten file)
   ./emsdk activate latest
   
   # Activate PATH and other environment variables in the current terminal
   source ./emsdk_env.sh
   

2. Compile with cmake:

   WASM works better with static libraries, as the binary is supposed to run in a browser.

   EXPECT_DEBUG_DEATH was not found.

   If you want to run the examples, add set(CMAKE_EXECUTABLE_SUFFIX ".html") after the project() directive.

   emcmake cmake -S cpp -B cpp/build -DMEMILIO_BUILD_SHARED_LIBS=OFF -DMEMILIO_BUILD_TESTS=OFF

3. Build: cmake --build cpp/build -j10

4. If built with html suffix, you can run emrun cpp/build/bin/<example>

Pyodide packaging

1. Install pyodide-build from pip. Set up emscripten with the first step above, but replace the version "latest" with 5.0.3 (for pyodide-build 0.36.0)
2. Create a wheel using pyodide build -Ccmake.define.MEMILIO_BUILD_SHARED_LIBS=OFF pycode/memilio-simulation. The wheel will be stored in dist/.
3. For testing the wheel, you need a new env from pyodide. This requires a Node.js installation: pyodide venv venv-pyodide && source venv-pyodide/bin/activate
4. pip install dist/<wheel-name>
5. Run examples to verify installation.

WASM notebook

This section needs some figuring out... The steps might look like:

• build and run a Emscripten marimo (or some other notebook/platform)
• use the same Emscripten/Pyodite toolchain to compile memilio-simulation
• install wheel in the notebook via import micropip; micropip.install("memilio-simulation"); import memilio.simulation
  • the import can technically take file:/// though hosting the wheel might be easier?
• ???
• profit

[reneSchm]

@HenrZu If you want to take over, have fun ;)