Add Windows building

build/.gitignore

@@ -1,3 +1,5 @@
 septadrop
 *.deb
-DEBIAN/usr/games/septadrop
+DEBIAN/usr/games/septadrop
+windows
+upx.exe

build/windows.bat

@@ -0,0 +1,49 @@
+@echo off
+SET TARGET=windows
+SET REQUIRED_DLLS=csfml-audio-2.dll csfml-graphics-2.dll csfml-system-2.dll openal32.dll
+REM Using UPX 3.96 results in the executable being marked as a virus by Windows.
+SET USE_UPX="n"
+IF %USE_UPX% == "y" (
+	IF NOT EXIST upx.exe (
+		ECHO Can't find upx.exe. You can download the latest UPX release from GitHub: https://github.com/upx/upx/releases
+		EXIT /b
+	)
+)
+SET missing_ddls="n"
+for %%a in (%REQUIRED_DLLS%) do (
+	IF NOT EXIST ..\target\release\%%a (
+		ECHO Can't find %%a in target\release.
+		SET missing_ddls="y"
+	)
+)
+IF %missing_ddls% == "y" (
+	ECHO You can download the required DDLs from SFML's website.
+	ECHO SFML 2.5.1:  https://www.sfml-dev.org/download/sfml/2.5.1/
+	ECHO CSFML 2.5.1: https://www.sfml-dev.org/download/csfml/
+	ECHO After downloading, copy them to target\debug and target\release, then try running this script again.
+	EXIT /b
+)
+IF EXIST %TARGET% (
+	RMDIR /S /Q %TARGET%
+)
+MD %TARGET%
+CD ..
+cargo build --release || (
+	ECHO Seems like something went wrong building the project, even though all required DDLs were found.
+	ECHO Have you copied all the appropriate .lib files for SFML and CSFML into your Rust toolchain's libraries folder?
+	ECHO If you're having trouble, please take a look at the following guides.
+	ECHO Rust SFML MSCV Windows Setup: https://www.youtube.com/watch?v=nnojR-8PT4M
+	ECHO rust-sfml Windows wiki page:  https://github.com/jeremyletang/rust-sfml/wiki/Windows
+	CD build
+	EXIT /b
+)
+COPY target\release\septadrop.exe build\%TARGET%\septadrop.exe > NUL
+for %%a in (%REQUIRED_DLLS%) do (
+	COPY target\release\%%a build\%TARGET% > NUL
+)
+XCOPY /E /D res build\%TARGET%\res\ > NUL
+CD build
+IF %USE_UPX% == "y" (
+	upx.exe --best --lzma %TARGET%/septadrop.exe
+)
+ECHO Finished building and packaging successfully! 

src/main.rs

@@ -1,3 +1,5 @@
+#![cfg_attr(not(debug_assertions), windows_subsystem = "windows")]
+
 use gcd::Gcd;
 use rand::seq::SliceRandom;
 use sfml::audio::*;