This article details my adventures and disadventures while porting my +9 years old XNA games (originally for Windows Phone) to multiple other frameworks (PSVita, Android and Desktop platforms).

At the beginning of 2012 I decided to create emegeme and start developing games. I got some experience with XNA framework so I decided to develop games for the new Windows Phone platform that was recently published and it was supported by the framework.

First game I developed was DART that TARGET, a darts arcade game. It took me about 3 months of work to create all the graphics and write all the code, it was released by April 2012. Sales were terrible.

DART that TARGET XNA game screenshots. I really put a lot of care in details, you can touch the neons for some sparks!.

DART that TARGET XNA source code development cost estimation analyzed with scc 3.0.0. A really motivational tool to evaluate my productivity.

Despite DART that TARGET did not work as expected, I decided to develop a second game, FLIPS, a memory cards game. FLIPS development took me about 4 months and it was released at the beginning of September. I put a lot of effort on localization (9 languages supported), it delayed the release a bit.

FLIPS XNA game screenshots. Again, I put a lot of care in details. I draw the 64 veggies cards available by hand!.

FLIPS XNA source code development cost estimation analyzed with scc 3.0.0. It does not reflect the amount od work it took me to create all the art!

Again, sales were terrible but thanks to that game I got a job offer to teach some videogames development lessons at a private educational institution, only for a couple of weeks... that turn into a 6 years full-time job!. During that time, I started a new project called raylib but that's another story.

By the end of 2014, I decided to give emegeme another try and, with the help of some of my students, we started working on games development again. By that time raylib was already a thing and some of the development efforts were put on it, actually, some of those efforts were the origin of raygui and several raylib features.

Beside raylib, two videogames project were started, one was Koala Seasons, a raylib game for Android that was never released on that platform but open-sourced and released for web later on.

Second videogame project was a port of FLIPS to other platforms. XNA was discontinued by Microsoft and MonoGame seemed to be the best alternative but it has many dependencies and the custom content processor tool was not ready yet, so, I decided to use SharpDX, a lightweight alternative to support Windows desktop platform; actually, MonoGame was using SharpDX internally at that moment.

FLIPS port from XNA to SharpDX started on November 2014 and it was done in parallel with another two big game changes: a redesign from portrait to landscape mode (to better accomodate on Windows desktop) and a code split for Engine and Game, the engine was called geme. The plan was using that engine for future projects... never happened.

geme game engine logo and structure. It was a very simple engine with just a bunch of classes, intended for 2D games.

By the end of 2014 FLIPS was already running on Windows desktop, it was nice, it allowed the project to live a bit longer than on a Windows-Phone-only platform but from a business point of view, Windows desktop was not the best platform for that kind of game (or that was what I thought at that moment). I decided to port the game again to a new platform: PSVita, using PlayStation Mobile (PSM).

PlayStation Mobile platform had been around for some time and it was intended for independent developers, the most interesting feature was that it supported C# to code games (using Mono), so, it seemed a really nice fit for FLIPS.

PSM API was similar in some aspects to XNA but it required more work than SharpDX to port so, this time the port approach was a bit different, instead of replacing all XNA functionality by PSM equivalents, I decided to create an auxiliar library to map XNA to PSM, that library was called XNA2PSM.

I'm not an expert on games porting but during those ports I realized that, usually, porting a game between platforms requires reviewing some common elements. I thing most SDKs provide this kind of base elements:

• Graphics Device Manager: Functions for Graphic Device initialization and drawing on it.
• Content Manager: Functions to manage loading/unloading assets data.
• Inputs Manager: Functions to read and manage inputs, usually Keyboard, Mouse, Gamepad and Touch inputs.
• Storage Manager: Functions to access some persistent storage system to save and load game info.
• System-specific features: For example networking, ads, trophies, system-level error messages, etc.

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FLIPS PSM source code development cost estimation analyzed with scc 3.0.0. Interesting to note the increment in code complexity compared to XNA.

Porting FLIPS to PSM took longer than expected but it was finally released on June 2015, after 5 months of development and working on it as a second job, also working full-time as a teacher.

FLIPS for PSVita (PSM) promotional trailer. Published one month before the platform closing. 😔

Unfortunately, Sony announced that the PSM store was closing by 15 July 2015, so, FLIPS was on the market for about 1 month until it dissapeared forever. All the technologies I had used to make games to that moment had end up disappearing (XNA/SharpDX/PSM) so I decided to focus my efforts on my own technology: raylib.

More than 9 years have passed since I released DART that TARGET and it's been more than 6 years since the last FLIPS port for PSVita PSM. During this time, I've released multiple raylib versions, several code libraries and even a set small tools for videogames development but I hadn't touched those games again... until now.

Recently I published raylib 4.0 and last week I decided to take a small break and try something different. I decided to port and publish FLIPS and DART that TARGET again.

This time I choose MonoGame for the ports, this framework has improved a lot in the last years and now it supports multiple platform seamlessly, so, I get down to the job and started porting those games again. The process took me about a week to get both games running on Android and Desktop (OpenGL) platforms.

Here are the details of the tasks done along this porting week:

• FLIPS: Define a proper project structure: My goal was to share as much code as possible between platforms so I decided to setup a solution with two projects (FLIPS.Android and FLIPS.Desktop) and link the source code from a common directory. I included the Content raw data with every project to be compiled by an MSBuild task on project compilation, same approach as the one proposed by MonoGame project templates.

• FLIPS: Manual Content compilation: I decided to move the Content raw data to a common directory outside of the projects and just keep the compilation config file (Content.mgcb) inside every project; I also tried to configure the output directories for the compiled data. Unfortunately, it didn't work, the MSBuild MonoGame task ignored my configurations and I couldn't get it working so I took another approach: Compile manually the assets for the desired platform and just properly add the compiled assets to the projects, it allowed me to remove the custom MSBuild task from the projects.
• FLIPS: Remove PSVita specific code: I removed the XNA2PSM library but there were still some #defines around the code for system-specific PSVITA code. I reviewed that code to get a running build (at least on Desktop platform).

• FLIPS: Code and formatting review: I reviewed most of the code, I did some cleaning and I also I reviewed code formatting. At that time I was not so concerned about clean code and naming conventions as I am today.

• FLIPS: Review screen and input scaling: The original XNA game was designed for a fixed resolution of 480x800, the PSM port was redesigned for a fixed 960x544. It was required to review that to support multiple resolutions. I just rendered the game to a Texture and then scaled it properly to the full display where the game is running. It also required inputs scaling to accomodate to the original resolution.
• FLIPS: Storage manager redesign: PSM implementation was specific for PSVita, it just accessed a byte array file and modified required bytes. I like that simple and low-level approach so I decided to keep it that way. I reimplemented the class to work that way but using the System.IO.IsolatedStorage; I got some problems with paths that took me longer than expected but I finally got it working on all platforms.
• FLIPS: Removed Ads manager: I just decided to remove ads, social networks sharing and trial version for the game. I decided to keep it as a premium simple game.

• DART: Complete project review: It was more than 9 years since last time I touched that code, project structure was unnecessarily comple, it had been greatly simplified for FLIPS but never back-ported, so, I decided to do a full review of the code. I removed the unneded classes, I replaced some classes and I did some code formatting and reorganization.

• FLIPS: Setup Google Play for publishing: I accessed my old developer account on Google Play and I start setting up the project for the release, filling all required information.
• DART: Redesigned InputManager: I decided to review game inputs, old implementation was using the gestures system only and I added support for Touch and Mouse, to allow playing the game on Desktop platforms. I also reviewed some other classes and I did some code cleaning.

• Start writing this article.

I decided to take a last step on the development and do a final port of those games, I decided to port them to raylib-cs.

Similar to what I did for PSVita PSM with XNA2PSM I decided to create an intermediate library to map XNA/MonoGame to raylib and I created Monotoray.

So, after almost 10 years since my first game was published, I was able to port my games to my own technology (or very close to it).