C-to-WebAssembly

Overview

• We followed the really cool blog from surma
  • Step1: (tagged step1)
    • First we will understand how we are generating wasm from C
    • Start with a simple function add.c
  • Step2: (tagged step2)
    • Turned our simple function into something more complex that will allow to:
      • move a small box within an area
    • game.c is the core of the application.
    • It provides three functions (See game.h):
      • game_init(): do the init of structure used,
      • game_render(): render the small box,
      • game_keydown(): to be able to move the box when pressing keys,
    • game.c requires functions defined in game_ext.h. These functions can be provided by:
      • JS: when running in the browser (main_wasm.js)
      • Raylib: when running as a standalone app (main_rl.c)
    • So we have two ways to run the code:
      • a standalone application that uses Raylib and that can be run using: ./game_rl
      • a web application that uses HTML Canvas for rendering. The game.wasm is generated from game.c.
  • Step3: (not tagger yet)
    • Can we only use one C file that uses Raylib but can also generates a wasm module?
      • In this case function provided by Raylib will be implemented in the main_wasm.js.
    • This will allow to have the same code for both renders.

Requirements

• llvm: we are using clang for compilation.
• raylib for the standalone application.
  • To install it we just untar the release in current directory.

Build

• make will build the standalone application and the WASM module.
• If you have python3 with http module you can do: make run that will build and start the http server for you.
• NOTE: build.sh is documented but has been replaced by Makefile after step1.