Aura

Official Site

Introduction:
Aura will be a 3D flying multiplayer game, with the object of shooting down as many other players as possible. There is a single-player option (against bots). The landscape engine uses texture-mapped voxels, with the other players being represented with scaled bitmaps. The graphics mode autodetects between Mode-X (320x240x256) and VESA (either 320x240x32-bit or 640x480x32-bit). Networking is be UDP/IP under Win95 or Win98. The entire project runs in 32-bit protected mode.

Team Members:

• Peter Johnson: Graphics, Networking, Gameplay, etc.

Problem Description:
Some of the more challenging parts of this project include:

• Voxel Graphics Engine: The texture-mapping voxel engine is a very complex piece of code in itself and will be very CPU-intensive. Optimizing this engine will be a major part of the project.
• Sprite Graphics Engine: For multiplayer, sprites will represent the other players. These sprites will be bitmaps, distance-scaled and positioned to show the position of the other player(s) in the landscape. 3D clipping will be quite a problem when integrating this engine with the voxel engine, and there may not be time to properly implement this clipping.
• Graphics Modes: As the engine renders in 24-bit color, making the output look as good as possible will be a function of how well the colors can be rendered to the display. For speed reasons with the voxel engine, the resolution should be kept as low as possible. Thus the ideal mode to run this game in will be the 320x240x32-bit VESA mode offered by SciTech Display Doctor (SDD). For backward compatibility, both a 640x480x32-bit VESA mode and a Mode-X (320x240x256) mode will be supported. The biggest difficulty here will be rendering the colors down (and the resolution down) into the proper format.
• DPMI Protected Mode: Due to the high memory usage of 32-bit graphics and textures, the project will be written using NASM and DJGPP to run in 32-bit DPMI protected mode under NT, Win9x, and DOS (Note: Under NT, SDD is not yet available and so the 320x240x32-bit mode will not be a graphics option--this may change with the next verison of SDD). Running in protected mode, while having many benefits, also has many pitfalls. Unique routines will need to be written for everything from file loading to memory allocation and interrupts.
• Networking: The current plan for network play is client/server UDP/IP. This networking mode will only work under Win9x--it will NOT work in NT or DOS. A fallback NetBIOS mode might be added if there is time. Due to the incredible complexity of interfacing with Windows TCP/IP, an external library will be used for this purpose.
• Single-Player: In addition to the multiplayer networked gameplay, individual gameplay may be added, with competition against computer-controlled bots. This will be a modular plugin into the multiplayer code--instead of going to the network to get positions of other players, the game will simply go to the bot code.

Implementation

Procedures (by Module)

Limited Source Code (by Module)

External Routines:

• libsocket 0.7.4 (beta 1): The library used to interface with Win9x TCP/IP. Some sample server code from this library will also be used to create the server-side component of Aura.
• DJGPP C libraries: Just for the rand() function (and functions used by libsocket).
• Original Mode-X routines: By Michael Abrash. Converted, extended, and optimized by Peter Johnson.
• Textures: Textures for the voxel terrain have all been taken from Half-Life and undergone digital manipulation using Photoshop.
• VistaPro 4: An excellent landscape generator and renderer used to create the landscapes for the game. The export format (heightmap and texturemap) is loaded verbatim into Aura--this makes map revision particularly simple.

Screen Shots:
Click here to see the screenshots.