Add build instructions for Windows.

diff --git a/README.md b/README.md
index 83e0648b1d8bd19100a88f88fd2452315007dd84..5754000027ae104f7a1f18d6781e0127bbbab8f2 100644 (file)
--- a/README.md
+++ b/README.md
@@ -3,21 +3,59 @@
 ## Overview
 
 MandelWow is a generalized version of Mandelbrot & Julia in which both C and Z0 vary in a 4-dimensional space.
-In each frame, we render a 3D slice of the MandelWow, varying the remaining dimension through time.
+On each frame we render a 3D slice of the MandelWow, varying the remaining dimension through time.
 
-I wrote this hack to learn Rust & basic GLSL. Mind the mess.
+I wrote this demo to learn Rust & basic GLSL. Mind the mess.
+
+
+## Requirements
+
+The native binary requires OpenGL 3.1. Should perform well on reasonably modern
+hardware. Tested on Linux with Intel HD Graphics 4000 (Ivy Bridge) and NVidia GTX 970.
+
+The asmjs and WebAssembly versions were tested on Chromium 57 and Firefox 53.
 
 
 ## Building from source
 
-### Native
+### Linux
 
-Install cargo, then simply type:
+Install cargo (either your distro's packaged version or via rustup), then go to the source root and type:
 
 ```
 cargo run --release
 ```
 
+### Windows
+
+Mandelwow depends on [libxm](https://github.com/nukep/libxm-rs) and [SDL2](https://github.com/AngryLawyer/rust-sdl2) for sound.
+Both are tricky to build using Rust's MSVC toolchain because they assume GCC, so I recommend using the GNU toolchain instead.
+I followed these steps to build a native Windows binary:
+
+* Install Cargo via [rustup](https://www.rustup.rs).
+* Install mingw-w64. The [MSYS2](http://www.msys2.org/) installer provides the basic shell environment and the package manager.
+* From the MSYS2 console, install the W64 native toolchain and libSDL2:
+  ```
+  pacman -Sy
+  pacman -S mingw-w64-x86_64-gcc mingw-w64-x86_64-SDL2
+  ```
+* While you're at it, you may also want to install the git package: `pacman -S git`
+* I had to manually add the mingw-w64 toolchain to your path:
+  ```
+  export PATH="/mingw64/bin:$PATH"
+  export LIBRARY_PATH=/mingw64/lib
+  ```
+* In case `cargo` and `rustup` aren't in the shell path, add `$USERPROFILE/.cargo/bin` too.
+* Next, install the Rust toolchain targeting GCC:
+  ```
+  rustup toolchain install stable-x86_64-pc-windows-gnu
+  rustup default stable-x86_64-pc-windows-gnu
+  ```
+* Now you can proceed to mandelwow's source tree and build a native Windows binary without further hassles:
+  ```
+  cargo run --release
+  ```
+
 ### WebAssembly / asm.js
 
 Install emsdk 1.36.14:
@@ -57,13 +95,6 @@ cd mandelwow
 ./release_wasm.sh
 ```
 
-## Requirements
-
-The native binary requires OpenGL 3.1. Should perform well on reasonably modern
-hardware. Tested on Linux with Intel HD Graphics 4000 (Ivy Bridge) and NVidia GTX 970.
-
-The asmjs and WebAssembly versions were tested on Chromium 57 and Firefox 53.
-
 ## License
 
 This project is GPL 3.0.