Day of Defeat: Source is a team-based online first-person shooter multiplayer video game developed by Valve. Set in World War II, the game is a remake of Day of Defeat. It was updated from the GoldSrc engine used by its predecessor to the Source engine, and a remake of the game models. The game was released for Microsoft Windows on September 26, 2005, distributed through Valve's online content delivery service Steam. Retail distribution of the game was handled by Electronic Arts.

The game was announced in February 2005. During the course of its development, Day of Defeat: Source progressed from being a straight conversion of Day of Defeat, to the alteration of certain aspects of the game's design and introduction of several features. In addition, Day of Defeat: Source has been used by Valve to present new design features on the Source engine, such as high dynamic range rendering and cinematic effects. The game itself revolves around two teams, the U.S. Army and the Wehrmacht, each with access to six player classes, fighting in a variety of scenarios inspired by World War II engagements in the European Theatre of 1944.

Upon release, the game received a generally favorable reception, praised for its atmospheric and strategic gameplay and its graphics, audio work and overall presentation. However, the game was criticized for the lack of content in it at the time of release, although subsequent updates to the game have added new game modes and levels.

Gameplay

left|thumb|A player surveys the beach landing at [[Anzio. This area acts as the insertion point for the Allied team.]]

Day of Defeat: Source is set in World War II, specifically the European Theatre in 1944. Players join the forces of either the United States Army or the German Wehrmacht and compete against each other in a variety of game modes. Players select from one of six classes to play as, each with its own role within the team. The strategic points take various forms, such as a destroyed tank in a street or fields and buildings, and are designated by a flag in its vicinity, which displays the army colors of the team who controls the point. Points are captured by a certain number of team members surrounding the point, with it either capturing instantly or after a couple of seconds. Grenades are carried by a number of classes, depending on their role in the game—riflemen are equipped with rifle grenades, the assault classes are armed with a single fragmentation grenade and a smoke grenade for providing concealment, while support classes have access to two standard fragmentation grenades. The game was opened to an internal beta test soon after, which certain members of the Day of Defeat community were invited to join. The beta version of the game was shown as a straight conversion of the most recent version of Day of Defeat, at the time even including the same player and weapon models as the game's GoldSrc counterpart. Due to the response of the beta testers, significant changes were made to the gameplay, taking it away from being a straight conversion: the behaviour of weapons was altered and several classes from Day of Defeat were dropped entirely. Later media releases showed the revamped version of the game, including its new player and weapon models, as well as new additions to the game, such as rifle grenades and smoke grenades. On September 2, 2005, Valve announced that they were "confident" that the game would be released that month, and seven days later announced an official release date of September 26, 2005. The game was made available for preload via Valve's Steam content delivery system on September 14, 2005, and was officially released on time on September 26.

Day of Defeat: Source has undergone several updates. These updates have consisted of gameplay tweaks, maps and graphical effects. The first new level was released on November 30, 2005, and was followed on January 25, 2006, by another map, used as a demonstration for the Source engine's abilities in rendering snow and ice. A major update was announced on June 22, 2006, adding the detonation game mode, various gameplay tweaks and two further maps to accommodate the new game mode. The update was released on June 28, 2006. On April 26, 2007, a group of maps produced by the game's community, entitled the Community Assembled Map Pack (CAMP1), was released. Consisting of three maps, the pack was created with the assistance and support of Valve. This was followed by CAMP2 on July 26, 2007, a pack which consisted of a further five maps. On May 23, 2008, Valve announced another major update to Day of Defeat: Source, this time giving the game support for the company's new Steamworks programmer. The update is open to any owners of Day of Defeat: Source. Along with various gameplay tweaks, the update moves the game to the Source engine version used with The Orange Box, allowing the game to utilize particle effects, as well as adding a map based on a long-standing custom map for Day of Defeat and 54 achievement awards for players completing certain tasks.

Technology

thumb|right|[[Depth of field, color correction and film grain effects used in the trailer]]

Day of Defeat: Source has been used by Valve as a platform for demonstrating several technologies in the Source engine. Day of Defeat: Source introduced a dynamic audio system that was limited to non-player characters in Half-Life 2. Other effects were added post-release to make the game appear as if it were a World War II era film. The effects include motion blur, depth of field, film grain and color correction. Phong shading on the Source engine was added to Day of Defeat: Source with the major update in the second quarter of 2006. Two further trailers were released to promote the major update to Day of Defeat: Source in the second quarter of 2006. The trailers, both from the American viewpoint, displayed how the new detonation gameplay worked, emphasising teamwork as the key to success, as well as introducing the viewer to the two new maps added by the update. To further create interest in the game, Valve has opened Day of Defeat: Source to three free weekends, the first taking place on February 10, 2006, the second on July 8, 2006 and the third on July 4, 2008, where anyone with a Steam account could download and play the game for a maximum of 48 hours free of charge.

Reception

Day of Defeat: Source was given a positive reception, receiving ratings of 80/100 and 81% from the review aggregation sites Metacritic and GameRankings.