Cross-Platform Game Engine

In the first semester of my MSc Computer Science degree as part of the Games Development Architectures module we were tasked to design and implement a cross-platform game engine. A game would also be made using the engine.

The chosen platforms were a Windows PC and Windows Phone 8 device. I decided that considering Microsoft had developed a Universal Application framework for targeting both of these, I would utilise it. This was good from the point of view that it simplified the cross-platform compatibility, but introduced a few limitations (namely having to work with the Windows RT platform and resultant consequences for dealing with inputs via ‘ref classes’ etc.. Coming from experience with Win32 desktop programs, Windows RT feels very different to program for and much less flexible, but then again Win32 really does need some modernisation.

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Project Details:

  • Engine coded in C++ (Visual Studio).
  • DirectX11 rendering engine component coded from scratch.
  • HLSL shaders.
  • The Universal App framework used to contain the code solution and deploy to both platforms.

We were given a design specification for a simple game called ‘Tunnel Terror’. It involved the player having to control a vehicle/object through a tunnel, avoiding various obstacles. The speed would gradually increase the longer the player survived and any collisions with obstacles would result in death. Score was determined by length of survival. I decided to add various extras including power ups such as coins and a randomised speed-up/slow-down. The game would need to play on both a PC and Windows Phone 8 device, allowing for the differing input controls to play. I decided the PC would utilise keyboard whereas the phone would rely on the accelerometer (tilt) sensor to manoeuvre the player through the tunnel. The PC also required a 2 player mode. Main menu, high score table and game over screens would be needed as well as Multiple camera modes such as first-person, third-person and death fly-by cameras.

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Although marks were given for the game implementation and extra features, much of the module was graded based on the engine design, implementation and accompanying report. My report justified the design based on four principles of games architecture, namely ‘Simplicity’, ‘Reusability’, ‘Abstractness’ and ‘Modularity’. Below is an example of the UML design used for my engines platform independent rendering component, with examples given to how behaviour could be derived for both DirectX and OpenGL.

Renderer

In the report we also had to research how we would have implemented the game on next-generation architecture such as the PlayStation 4 and how the engine would deal with the addition of different kinds of input devices.

There were some marks awarded for graphics quality and since the target platforms were both Microsoft, DirectX11 was used for the graphics. I implemented normal bump mapping to give it a nice look when flying down the tunnel. I also randomly changed the textures of each tunnel section and reset them to the end of the sequence once passing behind the frustum to give the impression of an endless tunnel with non-repeating sections.2

Annoyingly because the game is a Windows Store application there is no runnable executable so without actually publishing it to the Store and getting past all the certification requirements I cannot put it up anywhere to play! What is worse though is that currently I know of no screen capture software that can even record footage of the game running (at a decent FPS), both Fraps and Bandicam do not capture it since it’s not a desktop application. Bandicam does have desktop capture support but this also didn’t seem able to see the game and is not suitable for high frame-rate applications. So, as it stands I can’t make a video of the game running without hardware recording. Hopefully, this is something that won’t always be the case.

I was very pleased with the final engine and received a 92% grade for the module. I have since improved upon it and reused design elements for subsequent modules such as Real-time Graphics. I think a lot of what I coded for this project will be extremely useful going forward.

 

 

 

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