Doom95

Doom95 is an official source port of Doom to Win9x operating systems. This port was created by Microsoft to serve as a flagship for their DirectX technology, and was released on August 20, 1996. It supports four screen resolutions (320x200, 320x240, 640x400 and 640x480) and has a launcher to configure options for external PWADs, player controls and multiplayer settings. It has a slightly higher visplane limit than the original Doom, allowing for more complicated maps. Doom95 works with Doom, Ultimate Doom, Doom II and Final Doom. It also has cheat codes that are exclusive to it, such as the ability to kill all of the monsters in a level.

History
In late 1995, Doom was estimated to be installed on more computers worldwide than Microsoft's new operating system Windows 95, despite million-dollar advertising campaigns for the latter. The game's popularity prompted Bill Gates to briefly consider buying id Software, and led Microsoft to develop a Windows 95 port of Doom to promote the operating system as a gaming platform. One related presentation to promote Windows 95 had Bill Gates digitally superimposed into the game.

The team at Microsoft who ported Doom to Windows was lead by Gabe Newell, who later co-founded Valve Software and developed Half-Life.

Bugs
Due to a bug in its handling of modern graphics cards, Doom95 does not render partial invisibility in its original form. Instead of seeing directly through the sprite, the player sees a wall texture or other background "refracted" through the creature's body at a slight angle, as though looking at an object through a glass of water. This makes invisible enemies somewhat easier to see, especially in dark rooms; on the other hand, tracking the movement of non-invisible creatures behind them can be more challenging, especially when trying to aim one's weapon through a pile of invisible corpses (which can easily occur, for example, in E1M9: Military Base). The bug can be prevented by disabling DirectDraw acceleration using the -emulate command line argument.

A bug in Doom95 prevents demo recording. As soon as the game is launched (with instructions to record a demo), Doom95 quits and returns to the desktop with an error: "I_Error says: demo recorded". An unofficial patch has been released that fixes this bug (by altering the file DOOMLNCH.DLL).

Mice do not work with Doom95 under Windows 2000/XP. This is because these operating systems do not support VXD files (Doom95 uses the file DMOUSE.VXD to communicate with the mouse).

The automap function for marking the current position with a number is extremely buggy. In addition to severe rendering bugs, the actual markers are not displayed at all or are displayed in the wrong positions. Adding the markers can even crash the game, though this is rare. The automap can be restored from the buggy state by moving the view away from the marker or by clearing all marks.

The intermission screen background shown during Thy Flesh Consumed intermissions is the one from Knee-Deep in the Dead, and the level names are from that episode as well. The bug only affects the intermission screen: in the automap the level names are correct.

After MAP30 of Doom II has been completed, a few frames of the monster animations are displayed in the upper left corner of the screen instead of the center. This seems to affect the Hell Knight, Arachnotron, Revenant, Arch-Vile, and Spider Mastermind.

While not necessarily a bug, the sound effects are played back at a slightly lower pitch than in regular Doom played under DOS.

Differences between vanilla Doom and Doom95
Unlike the later vanilla versions, Doom95 cannot play back true MIDIs, only real MUS files.

Some of Doom95's quit messages differ slightly from vanilla Doom, mostly by removing references to DOS.