Add README, improve build script help

README.md

@@ -0,0 +1,19 @@
+# rust-sdl2-emscripten
+
+This is an experimental repository while testing a Rust + SDL2 project built with Emscripten.
+
+- [hello-rust-sdl2-wasm](https://github.com/awwsmm/hello-rust-sdl2-wasm) - A bit of a weird repository, I'm not sure that the creator knows Rust that well, but it compiles. Note that the `asmjs-unknown-emscripten` target is deprecated, and you should use `wasm32-unknown-emscripten` instead. You'll need to change all the files, flags etc. to make it match.
+
+- [build.sh](./scripts/build.sh) - One of the core files in this repository, it builds the project with Emscripten. Note all the flags available for modifying the behavior of the build.
+
+### Goals
+
+- [X] Reproducible SDL2 Emscripten Builds
+  - This ensures that the project can iterate safely and be inspected in a safe environment, free from errors. Helps ensure errors are isolated to the machine or build script.
+- [ ] SDL2 Image, TFF, Mixer Usage
+  - All of these libraries are common and necessary for a lot of projects. Ensuring they work is important.
+- [ ] Example of External Javascript Interop
+  - The basic ability to provide some kind of Javascript binding would be important for a decent web-based project or game.
+  - The ability to use localStorage, fetch, or some browser-only API would be important.
+- [ ] Windows, MacOS, Linux Builds
+  - Simple ability to provide multi-platform builds in addition to the WASM build.

scripts/build.sh

@@ -7,14 +7,19 @@ skip_emsdk='false'
 clean='false'
 
 print_usage() {
-    printf "Usage: -r RELEASE -d DEBUG -s SERVE\n"
+    printf "Usage: -erdsc\n"
+    printf "  -e: Skip EMSDK setup (GitHub workflow only)\n"
+    printf "  -r: Build in release mode\n"
+    printf "  -d: Build in debug mode\n"
+    printf "  -s: Serve the WASM files once built\n"
+    printf "  -c: Clean the target/dist directory\n"
 }
 
 while getopts 'erdsc' flag; do
     case "${flag}" in
     e) skip_emsdk='true' ;;
     r) release='true' ;;
-    d) release='false' ;;
+    d) release='false' ;; # doesn't actually do anything, but last flag wins
     s) serve='true' ;;
     c) clean='true' ;;
     *)