Gratuitous Space Battles (GSB) is a video game developed by the UK-based company Positech Games. At a high level, the title is a space battle simulation consisting of a number of engagements between two opposing fleets of ships. While sometimes assumed to be a real-time strategy (RTS) game based on screenshots, actual gameplay focuses on the setup prior to the battle, making it play more like a tower defense game.
Gratuitous Space Battles challenges players with defeating opposing space fleets through careful pre-battle planning. For each skirmish or engagement, the player has a fixed budget and a maximum number of ships (pilots), as well as various other limitations or rules which influence the outcome of the battle. For example, a given environment may reduce the effectiveness of ship shields, or may reduce weapon ranges. Players must take this information into account when selecting and positioning the ships that form their own fleet. Once players have selected their ships and issued orders to the ships concerning how to engage the enemy fleet, the battle begins. The battle itself proceeds completely without human interaction, with the outcome being determined entirely based on the data, rather than on player reflexes or mid-battle decisions.
Gratuitous Space Battles encourages players to win battles using as few resources as possible by awarding honor for any unspent funds. That is, for each point of budgetary allocation which a player could have spent but did not, a point of honor is awarded upon victory. The game tracks the maximum honor previously awarded per battle at each difficulty level, so players can continue to earn more only by beating their previous best. After amassing a sufficient quantity of honor, it can then be traded (spent) to unlock new ship modules, new ship hull configurations, and new playable alien races.
As Gratuitous Space Battles consists solely of combat in space (foregoing any of the other elements of a traditional 4X game), it gives players a great deal of flexibility in how ships are designed. For a given playable race, players have a number of hull configurations from which to choose, made up of three different sizes of ships (fighters, frigates, and cruisers). Different ship hulls have different numbers of mounting points for modules and weapons, as well as having various inherent characteristics (in the form of overall bonuses in specific areas). Players must balance ship cost, weight, speed, power, crew, and offense/defense capabilities in deciding what combat role a given spacecraft will fulfill.
Gratuitous Space Battles began as a "dictator simulation" in late 2008 when Chris "Cliffski" Harris was starting on his next game after Kudos 2. After only several weeks of work on the initial concept of a "Virtual Saddam" game, the title went in an entirely different direction and instead became a space strategy game.
As with many indie video game projects, development cost was a significant issue. After an initial experiment spending several hundred dollars to purchase stock spaceship models, Harris eventually solicited quotes from 3 different artists and selected the most expensive one. The user interface was constructed by Chris Hildenbrand, a UI expert, leaving Harris to do his own special effect and user module graphics.
To maximize performance and minimize texture swapping, the graphics engine used for GSB was an entirely new DirectX 9 engine that was custom-developed for the game. It includes a variety of special case code to deal with the requirements of rendering ship and weapon graphics during battles.