Source

id Tech 2 ▶ GoldSrc ▶ Source ▶ Source 2

Screenshot in-game of Counter-Strike: Source, using the Source Engine.

Screenshot taken in-game of Counter-Strike: Global Offensive, which uses a newer branch of the Source Engine.

Source is a 3D game engine created by Valve, it is the successor to GoldSrc. Source has been used by Valve, third-party companies, and (much like GoldSource) countless community mods by people around the globe.

Renderer

• Version 3.0 (and below) shaders
• Bump mapping and Normal mapping on models and the world
• Author shaders with HLSL
• Cube and environment mapping
  • Cubemapping also supports Anisotropy (in all games since )
• Phong shading for models
  • Phong is also supported on world brushes (in all games since )
• Dynamic lights, vertex lighting and lightmaps, many light types including flickering, pulsing etc.
• HDR (in all games since ) and SDR/LDR (not in and later) lighting
• Water with refraction, real-time world reflections and fresnel effects
  • Water also supports flow mapping (in all games since )
• Advanced particle systems that can emit sprites or models
• Render-to-texture shadows allow for a large number of characters per scene
• Occluder entities for visibility blocking
• Indoor/Outdoor environments
  • Deformable terrain
  • 3D Skyboxes extend the horizon and add parallax on distant objects
  • Dynamically rendered organics (grass, trees, etc.)
• Subdivision surfaces, diffuse & specular bump maps
• Real-time radiosity lighting
• Real-time cascaded shadow mapping that comes from the skybox (in all games since )
• Effects include but are not limited to: particles, beams, volumetric smoke, sparks, blood, & environmental effects like fog and rain
• Scalability
  • DX8-DX9 hardware supported (DX6-DX9 with modifications and fixed-function shaders)
    • DirectX 9 only (in all games since )

Materials System

• Instead of traditional textures, Source defines sets of materials that specify what the object is made from and the texture used for that object. A material specifies how an object will fracture when broken, what it will sound like when broken or dragged across another surface, and what that object's mass and buoyancy are. This system is much more flexible than other texture-only systems
• Materials can interact with objects or NPCs, such as mud or ice for vehicles to slide/lose traction on

Multiplayer Network Code

• Time- and gamer-tested by millions of gamers around the world
• Support for both LAN-based multiplayer and Internet-based multiplayer games
• Prediction analysis for interpolating collision/hit detection
• Optimizations for high-latency, high-packet-loss 56k connections

Advanced Characters

• Detailed and believable characters
• Realistic eyes
  • Focus on player/object, not simply parallel views
  • Proper eye bulge for realistic eye reflections
• Simulated musculature provides outstanding emotions, speech, and body language
• Language independent speech, characters can speak naturally in many languages
• Skeletal/bone system for animation
• Layered animation system can synthesize complex animations out of several pieces

Physics

• More responsive world with realistic interactions
• Sounds & graphics follow from physics
• AI characters can interact with physically simulated objects
• Ropes/cables, machines, constraint systems, ragdoll physics
• Can be controlled by level design
• Kinematic animated bone followers
• Custom procedural physics controllers
• Vehicles
  • Wheels slip and skid
  • Realistic suspensions with springs on each wheel
  • Realistic leaning during acceleration/deceleration and turning
  • Individually tunable parameters such as horsepower, gearing, max speed, shift speed, tire material, tire friction, spring tension/dampening, etc.
  • Multiple players in a vehicle in multiplayer
  • Hovercraft support for cheaper simulation

Advanced AI

• I/O system allows level designers to control AI
• Sophisticated navigation: characters that run, fly, jump, crouch, climb stairs and ladders, and burrow underground
• AI senses things using sight, sound, and smell
• AI relationships determine friend/foe status of other entities
• Battle AI allows squads of AI characters to operate together, know when to advance, retreat, lay cover fire, etc.

Sound System

• 7.1, 5.1 surround sound, 4 speaker surround

• High-quality 3D spatialization
• Custom software DSP
• Automatic DSP based on environmental geometry
• ADPCM decompression
• 16-bit 44KHz, stereo wave data with all features
• MP3 decompression (requires Miles license)
• Support for audio streaming on any wave
• Real-time wave file stitching
• Pre-authored Doppler effect encoded waves
• Pre-authored distance variant encoded waves
• Commentary system

UI

• Server browser — Displays all active game servers and allows a player to choose which one to participate on. Players can filter and sort server lists in order to speed up the display and selection of a server.
• VGUI — Valve's custom GUI interface mimics most of the Windows controls but is rendered using the Source engine for both in game and out of game uniform UI display. Some features:
  • Dynamic in-game HUD display
  • Many widgets/controls (e.g., buttons, treeview, html control…)
  • Themes/custom visualization allowed
  • Platform independent
  • Localized text (Unicode compliant)

Programming

• All code written in C/C++ using Visual Studio .NET 2003 and later. Easily and quickly derive new entities from existing base classes
• Internal context sensitive performance monitoring system
• Graphics performance measurement tools built into the engine
• Modular code design (via DLLs) allows swapping out of core components for easy upgrading or code replacement
• VScript scripting system allows using external coding languages, such as Squirrel and Lua, in maps to create more complex systems (in all games since ) (also in )

Tools

• HLFaceposer
  • Facial expression tool used to craft speech and emotions
• Valve Hammer Editor
  • WYSIWYG World editor
  • Create world brushes
  • Terrain editor
  • Place detailed world models and AI NPCs
  • Set navigation points/paths for NPCs
  • Place triggers, clip brushes, logic, etc.
  • Allows level designer to hook up I/O between entities to control AI within the game
• Half-Life Model Viewer
  • Full model previewer
  • Rotate models in any direction
  • Set up hit boxes
  • View physics hull
  • View normals
  • Wireframe, shaded or textured view modes
• Studiomdl
  • Model compiler
• VBSP, VRAD, VVIS, VMPI
  • Map compilation tools (bsp, lighting and visibility)
  • VMPI — distributed compilation tool allowing level compiles to be spread across many PCs greatly reducing compile times
• Exporters
  • XSI, Max and Maya .smd exporters for exporting 3D models

Games on Source

Valve

Games made by Valve.

• 2004 Counter-Strike: Source
• 2004 Half-Life 2
• 2004 Half-Life 2: Deathmatch
• 2004 Half-Life: Source
• 2005 Half-Life 2: Lost Coast
• 2005 Day of Defeat: Source
• 2006 Half-Life Deathmatch: Source
• 2006 Half-Life 2: Episode One
• 2007 Half-Life 2: Episode Two
• 2007 Portal
• 2007 Team Fortress 2
• 2008 Left 4 Dead
• 2009 Left 4 Dead 2
• 2010 Alien Swarm
• 2011 Portal 2
• 2012 Counter-Strike: Global Offensive
• 2013 Dota 2 - Formerly, now using Source 2 since 2015.

Third-Party

Games and mods made by third-party companies and mod teams.

• 2004 Vampire: The Masquerade – Bloodlines
• 2006 SiN
• 2006 The Ship: Murder Party
• 2006 Dark Messiah of Might and Magic
• 2006 Zombie Panic! Source
• 2007 Zeno Clash
• 2009 Vindictus
• 2010 Bloody Good Time
• 2011 Dino D-Day
• 2011 E.Y.E: Divine Cybermancy
• 2011 Nuclear Dawn
• 2011 No More Room in Hell
• 2011 Postal III
• 2012 Dear Esther
• 2012 Revelations 2012
• 2013 Tactical Intervention
• 2013 The Stanley Parable
• 2013 Consortium
• 2014 Insurgency
• 2014 Titanfall
• 2014 Contagion
• 2014 Lambda Wars
• 2015 Portal Stories: Mel
• 2015 Blade Symphony
• 2015 Double Action
• 2015 The Beginner's Guide
• 2016 INFRA
• 2016 Titanfall 2
• 2016 Day of Infamy
• 2017 Alien Swarm: Reactive Drop
• 2017 Entropy : Zero
• 2018 Hunt Down the Freeman
• 2019 Apex Legends
• 2020 Black Mesa
• 2020 G-String
• 2021 Portal Reloaded
• 2022 Divinia Chronicles
• 2022 Entropy : Zero 2
• 2022 JBMod
• 2022 infestus
• 2022 Jabroni Brawl: Episode 3
• 2023 Portal: Revolution
• 2023 Military Conflict: Vietnam

Unreleased

This section are for unreleased games that doesn't have their release date announced yet.

• 2023 (Upcoming) Swelter
• TBA Director's Cut
• TBA Momentum Mod
• TBA Portal 2: Community Edition
• TBA PUNT

More Third-party Source Engine games

• More Source mods

See Also

• Wikipedia:Source (game engine)