Bad Mood

Bad Mood is a Doom hybrid custom engine and source port created for the Atari Falcon 030. It is distinguished by its ability to maintain a playable frame rate on unmodified hardware, such as models with a 16MHz 68030 CPU and 32MHz DSP.

History
Development of Bad Mood began in 1995. Initial versions were written in C, based on an Atari port of DView by Jake Hill, which was able to render Doom maps, albeit without texture mapping. These initial versions were slow on non-custom hardware. This initial architecture was optimized by the Bad Mood team using assembly routines to accelerate rendering of the flat-shaded maps. The last release of a version using this architecture was version 1.32a, released in November 1995.

DSP code, additional optimizations, and code for rendering of textures and sprites were added to the engine, with significant contributions from Doug Little, who was a well known developer in the Atari Falcon community. At this point the port still remained a map viewer rather than a fully playable game.

Following the 3.07a release of August 1997, development halted until 2013 due to lack of developer interest and occupation with other projects. This was partially related to the 1997 release of the official Linux source code, reducing interest in development of a custom engine. As demonstrated by the PmDoom source port, however, performance of a straight port of the official code to the Atari could not produce acceptable performance on all but the most powerful of these machines.

Doug Little returned to Bad Mood development in 2013. He merged the Doom codebase with the existing Bad Mood rendering engine and several additional optimizations to both the gameplay simulation and rendering code, creating a playable game.

Features

 * Supports Atari Falcon "True Colour" mode, particularly useful for supporting distance fading effects.
 * Ability to render individual textures with distinct palettes.
 * Liquid shaders capable of texture deformation.