This page documents information about a third-party game running on a non-Valve engine. This information is documented here because it has technical and/or historical relevance to Valve's engines.
Todo: Elements relevant to Valve's engines (ex: skybox format, colored lighting, translucency, BSP format, etc.).
Quake II (1997) is the second installment of the Quake series, following Quake. The game moves away from the original Gothic Lovecraftian horror theme and instead, making the game more sci-fi aesthetic.
Like it's predecessor, the Valve's GoldSrc engine also used most of the code from Quake II Engine as far back during it's early development, through later in the final version it used the heavily modified Quake Engine, with only few Quake II engine code. Another game, such as SiN by Ritual, also used Quake II engine, which they licensed from id Software.
Furthermore, Half-Life was originally planned to be released in November 1997 to compete with Quake II (which would be released in Dec 1997), but it's was later delayed to 1998 with Valve reworking every level of the game.
Quake II was originally released in December 1997 for PC, then later ported to both Nintendo 64, PlayStation 1 in 1999, along with Classic Mac OS, Linux and BeOS operating systems, which all of them are also released in 1999. It is also ported to Xbox 360, available on Quake 4 bonus disc.
Quake II RTX
In March 2019, a remaster of Quake II, called Quake II RTX was announced by Nvidia, and later released in June 6 for both Windows and Linux. As the name suggest, you need a NVIDIA RTX, Intel Arc or AMD Radeon RX 6000 series card in order to enable ray-tracing, but the game offers software fallback for cards that are fast enough.
It is available for free on Steam with three demo levels included, but RTX version was able to play the full game as long the original game files were installed.
2023 Kex Engine remaster
Also known as Quake II Enhanced, and colloquially referred to as Q2EX.
Another remaster of Quake II was released for the Nintendo Switch, PlayStation 4, PlayStation 5, Windows, Xbox One and Xbox Series X/S on Aug 10, 2023 during QuakeCon. These runs on Kex Engine on top of modified version of id Tech 2 engine.
This is a first time that Quake II was officially ported to modern consoles, with 1080p 60FPS rendering on 8th gen consoles, while Windows, PS5, Xbox One X, and Xbox Series X|S are able to run on 4K (or higher on PC) up to 120FPS (or more on PC). It also introduced new single-player expansions, "Call of the Machine", which was designed exclusively for the remaster by Bethesda studio MachineGames, comprising 28 additional levels and a new Deathmatch map. A Nintendo 64 port of the game was also bundled with the remaster, as a bonus game.
Additionally, the game runs at a 40 Hz tickrate as opposed to the original's 10 Hz, and it's does not use any bilinear filtering for the textures at all unlike the original with OpenGL mode. 13 new achievements has been also added to the game.
Confirm: Does the Enhanced/2023 Kex Engine remaster have any texture filtering like the original running in OpenGL mode?
- John E. Laird. 2001. It knows what you're going to do: adding anticipation to a Quakebot. In Proceedings of the fifth international conference on Autonomous agents (AGENTS '01). Association for Computing Machinery, New York, NY, USA, 385–392. https://doi.org/10.1145/375735.376343
Thanks to the release of the Quake II source code, there have been many source ports that seek to supersede the vanilla engine. The following modern source ports are actively or semi-actively developed:
- Yamagi Quake II - Vanilla-friendly source port. Singleplayer-focused; multiplayer may be too insecure for netplay.
- Q2Pro - Multiplayer-focused source port, with added security fixes, optional anticheat, and many enhanced graphical features.
- Q2RTX (Quake II RTX) - Fork of Q2VKPT (which itself forked from Q2Pro) with real-time raytracing.
- KMQuake II - Feature-focused source port, aimed at removing limits to increasing mapping potential.
- Quake II XP - Graphics-focused source port, porting the graphics pipeline to modern GLSL. Aims to remaster the visuals without sacrificing the original "style" of the game.
For more source ports, see Source ports section on PCGW.
Important:Transparency and Translucency:
- Only translucency is supported in vanilla; alpha testing requires certain source ports (Notably not in Yamagi).
- Translucency is only supported on worldspawn textures and SP2 sprites, and cannot be used on brush entities or MD2 models in vanilla, due to the usage of the BSP tree for alpha sorting.
Compare to GoldSrc, which supports translucency on any brush entity except worldspawn (as well as models and sprites).
Some source ports (such as KMQuake2) support translucency on brush entities, but exhibit the same alpha sorting issues as GoldSrc.
Only in modern versions of Windows or modern PC
Like most unpatched games from the 1990s, the game can usually have issues and bugs when played on modern systems and modern version of Windows. You can check the Issues fixed section on PCGW for more information.
Enhanced version (2023 Kex Engine remaster)
Bug:Steam Cloud in the enhanced version of the game was misconfigured by the developers. As a result, only configurations files are synced, not the save files.
☑ Resolved: Fixed in August 15, 2023 update. 
- wolfinston85 on Steam Community:
Does Steam Cloud only support options and not saves? - last accessed on 2023-08-11
- Quake II History · Change #19910560 · SteamDB - last accessed on 2023-08-16