Compiling Agar on Windows with Visual Studio

This guide describes how you can use Agar to compile an application using Microsoft Visual Studio 2005, 2003, 2002 or v6. It also describes the procedure for compiling Agar itself under Visual Studio. It assumes that you already have both the Microsoft Windows SDK ("Platform SDK") and the Visual C++ 2005 Redistributable Package installed on your system.

Installing Agar

Get the latest Agar Windows binary package from the download page. You can unpack the archive to a location such as C:\Program Files\Agar.

Start Visual Studio and bring up Tools / Options. Select Projects and Solutions / VC++ Directories. In the Show directories for field, select the option Include files. If you have unpacked the Agar SDK package into C:\Program Files\Agar, for example, insert the line:

  C:\Program Files\Agar\include

Now select Show directories for / Library files and insert the line:

  C:\Program Files\Agar\lib

Installing SDL

As of version 1.3, Agar requires SDL. If you have not already installed the SDL development package, go to the SDL download area, download the file SDL-devel-1.2.*-VC8.zip (or -VC6.zip), unpack its contents into a location such as C:\Program Files\SDL and add C:\Program Files\SDL\include to your include path and C:\Program Files\SDL\lib to your library path like you just did with the Agar SDK.

You will also want to copy SDL.dll to your C:\Windows\System (or C:\Windows\System32 on Windows x64). If you are going to be redistributing your application, you might want to include SDL.dll, README-SDL.txt and COPYING in the package.

Optional: Thread support

If you have installed one of the nothreads flavors of the Agar SDK, you can skip this section.

Thread safety and support for thread management in Agar-Core requires the POSIX threads API. Even if you are not using threads directly, network applications usually require threads to prevent blocking of the GUI during network operations.

POSIX threads are supported natively by all modern, decent operating systems. Under Windows, you will need to install a small library called Pthreads-win32. Go to the Pthreads-win32 download area, get the latest version (pthreads-w32-2-x-x-release.exe) and extract to in some temporary location. Rename and move the Pre-built.2 directory over to C:\Program Files\Pthreads.

Copy the DLL files (or at least PthreadVC2.DLL) from the lib subdirectory to your C:\Windows\System (or C:\Windows\SysWOW64 with Windows x64).

Go to Tools / Options / Projects and Solutions / VC++ Directories in Visual Studio and add C:\Program Files\Pthreads\include to your include path and C:\Program Files\Pthreads\lib to your library path like you just did for Agar and SDL.

Optional: Installing FreeType (from binary package)

If you have installed one of the nofreetype flavors of the Agar SDK, you can skip this section. Without FreeType, Agar will revert to a built-in, low-quality bitmap font engine (but you probably don't want to use it).

You can download a binary package of FreeType for Windows, which was compiled and tested using Visual Studio 2005, here: FreeType235-win32-i386.zip, and unpack it into a directory such as C:\Program Files\FreeType.

If for some reason this package doesn't work, there is also a package available from GnuWin32 (SourceForge download area), but you will have to rename lib/libfreetype.dll.a to freetype.lib (and copy bin/freetype6.dll to your C:\windows\system also or C:\windows\system32). You will probably get some linker warnings since the GnuWin32 binaries were not compiled with Visual C++.

Optional: Installing FreeType (by compiling it yourself)

If you would like to compile FreeType using Visual Studio yourself, follow these steps:

Go to the FreeType download area, download the latest source package (ft*.zip), and unpack it to some temporary location.

In the FreeType source directory, go to the builds\win32\visualc subdirectory and open up freetype.sln in Visual Studio. Locate the "Solution Configurations" selector in the Visual Studio toolbar, and select "Release Multithreaded".

Now build the solution. This will generate the .lib file we need. Then, right-click on the freetype project entry in Solution Explorer, go to Properties and locate Configuration Properties / General. In the Project Defaults section, set the Configuration Type field to Dynamic Library (.dll), and build the solution again, this time it will generate our .dll file.

Exit Visual Studio, and go to the build directory of FreeType (i.e., objs in the FreeType source directory). Locate the .lib file (e.g., freetype*MT.lib), copy it over to a new directory, such as C:\Program Files\FreeType\lib, and rename it freetype.lib. Then, locate freetype.dll in release_mt in the FreeType build directory, and copy it to C:\Program Files\FreeType\lib. You may want to copy this DLL to your C:\Windows\System or C:\Windows\System32 as well.

Copy the entire include directory from the FreeType sources to C:\Program Files\Freetype\include.

Like you just did with Agar and SDL, add the directories C:\Program Files\FreeType\include and C:\Program Files\FreeType\include\freetype2 to your include path and add C:\Program Files\FreeType\lib to your library path in Tools / Options / Project and Solutions / VC++ Directories. You should now be able to use FreeType from Visual Studio.

Creating an Agar application in Visual Studio

You can now create your application. In the Application Wizard, set Application type to Console application, check the Empty project box and click Finish.

In the Solution Explorer, go to Properties from the popup menu of your project. Click on Configuration Properties / Linker / System and set the SubSystem parameter to Windows (/SUBSYSTEM:WINDOWS). Click on Configuration Properties / Linker / Input, and add the following to the Additional Dependencies field:

  ag_gui.lib
  ag_core.lib
  SDL.lib
  SDLmain.lib
  opengl32.lib
  freetype.lib

If you are using a nogl flavor of the Agar SDK, you can remove opengl32.lib. If you are using a nofreetype flavor, you can remove freetype.lib.

Add a new C++ file to Source Files in the Solution Explorer, such as main.cpp. Here is a standard Hello World you can use. Your application should now compile and run properly.

Note: If you want your application to be portable to other operating systems and other development environments, consider the BSDBuild utility. It can even generate project files for you.

Compiling Agar itself with Visual Studio

If you are not using the precompiled SDK and would like to compile Agar yourself, look for the project files included in the .\ProjectFiles\ directory in the Agar source. Locate the .zip file matching your Visual C++ release, for example vs2005-windows.zip will work with all Visual C++ 2005 editions. There are also some flavors such as nothreads, which disable thread safety and nofreetype which does not depend on FreeType.

Unpack the archive into the very top Agar source directory, such that Agar.sln will end up in the same directory as Agar's README file.

Open Agar.sln with Visual Studio and you should now be able to compile the toolkit. Once Agar is compiled, run INSTALL-SDK.EXE in the root of the Agar source directory to install the libraries on your system. By default, they are installed into C:\Program Files\Agar.

Common issues

If you are getting this linker error:

  SDLmain.lib(SDL_win32_main.obj): error LNK2019:
  unresolved external symbol _SDL_main referenced in function _main

Make sure your main() is declared exactly as int main(int argc, char *argv).