How to use WebAssembly modules in a WeWeb project?

Step 1: Understand What WebAssembly Is

Before you start using WebAssembly modules in a WeWeb project, you must first understand what WebAssembly is. WebAssembly (also known as wasm) is a binary instruction format designed to be a portable target for the compilation of high-level languages like C, C++, and Rust, enabling deployment on the web for client and server applications.

Step 2: Ensure You Have the Required Tools

To run and test WebAssembly applications, you need to have a modern web browser (Chrome, Firefox, Safari, or Edge). These browsers have built-in support for WebAssembly. If you do not already have the Emscripten SDK (a cross-compiler toolchain), you need to install it as well.

Step 3: Setup the Emscripten SDK

First, clone the Emscripten SDK from GitHub to your local machine using the following command:

git clone https://github.com/emscripten-core/emsdk.git

Next, navigate into the cloned directory and pull the latest version:

cd emsdk
./emsdk update

Finally, install the latest SDK tools:

./emsdk install latest
./emsdk activate latest

Step 4: Create a WebAssembly Module

You need to code your WebAssembly module in a language that compiles to WebAssembly, such as C, C++, or Rust. Assuming you've coded your module in C++, you will need to compile it to WebAssembly using the Emscripten compiler.

To compile a helloworld.cpp program to WebAssembly, use the following command:

emcc helloworld.cpp -s WASM=1 -O3 -o helloworld.html

This will generate helloworld.wasm, helloworld.js, and helloworld.html files.

Step 5: Create Your WeWeb Project

After creating your WebAssembly module, you can then start your WeWeb project. On the WeWeb platform, you can create a new project via the "New Project" option. WeWeb is a great place to develop highly responsive websites.

Step 6: Add WebAssembly To Your Project

Once your WeWeb project has been created, you can add your WebAssembly module. Note that you will need the generated JavaScript file (helloworld.js in our example) and the WebAssembly file (helloworld.wasm).

In your WeWeb project, you will need to integrate and reference the JavaScript file, which will load the WebAssembly file. Here's how you do it:

• Upload the helloworld.js and helloworld.wasm files to your project's asset manager.
• Create a new custom code block in WeWeb and add a script tag that references helloworld.js.
• In the JavaScript code provided by Emscripten, replace the relative URL path to the .wasm file with the absolute URL of the .wasm file uploaded to the WeWeb asset manager.

Here's an example of how you could use the generated JavaScript file in WeWeb:

<script src="/path/to/helloworld.js"></script>

Now, when you load your WeWeb project in a web browser, the .js file will load and run the .wasm file.

Step 7: Use the WebAssembly Module Functions

Since the helloworld.js file will import the WebAssembly module, you can now access and use the module's exported functions. Please note that using the exported functions of a wasm module depends on the interfaces provided by the wasm module itself.

Step 8: Test Your WeWeb Project

Finally, once you have done all the steps above, do not forget to test your WeWeb project on different modern browsers to ensure that the WebAssembly module works perfectly as expected. You can view your project in a browser by clicking the 'View live' button in WeWeb.