Development of Doom
"Doom"s original release date was the third quarter of 1993, which the team did not meet. By December 1993, the team was working non-stop on the game, with several employees sleeping at the office; programmer Dave Taylor claimed that working on the game gave him such a rush that he would pass out from the intensity. Id began receiving calls from people interested in the game or angry that it had missed its planned release date, as hype for the game had been building online. At midnight on December 10, 1993, after working for 30 straight hours, the development team at id uploaded the first episode of the game to the internet, letting interested players distribute it for them. So many users were connected to the first network that they planned to upload the game to—the University of Wisconsin–Parkside FTP network—that even after the network administrator increased the number of connections while on the phone with Wilbur, id was unable to connect, forcing them to kick all other users off to allow id to upload the game. When the upload finished thirty minutes later, 10,000 people attempted to download the game at once, crashing the university's network. Within hours, other university networks were banning "Doom" multiplayer games, as a rush of players overwhelmed their systems.
Development of Doom
Over spring and summer of 1993, Carmack worked on improving the graphics engine of the game. After Romero's level designs started to cause problems with the engine, he researched and began to use binary space partitioning to quickly select the portion of a level that the player could see at any given time. Additionally, in March 1993, the company had to stop work on the game while the team spent three weeks building a Super Nintendo Entertainment System port of "Wolfenstein 3D", after the contractor who had agreed to do the port proved to have made no progress. Taylor, along with programming other features into the game, added cheat codes; some, such as 'idspispopd', were based on ideas their fans had come up with while eagerly awaiting the game. By fall, the game was nearing completion, with players eager to see it, spurred on by a leaked press demo. John Carmack began to work on the multiplayer component of the game; within two weeks he had two computers playing the same game over the internal office network. Soon, the office was playing four-player Deathmatch games.