The Source Engine is a 3D game engine developed by Valve Corporation. Its unique features include a large degree of modularity and flexibility, an artist-driven, shader-based renderer, accurate lip sync and facial expression technology, and a powerful, efficient and completely network-enabled physics system.

The Source engine was first shown to the world by being the power-horse behind the hugely anticipated Half-Life 2 which was released in late 2004. Since then the Source Engine has been upgraded with the release of such titles as Half-Life 2: Lost Coast, Team Fortress 2 and the Left 4 Dead series to name a few.

Whilst it has been years since the release of the Source Engine they haven't yet unveiled a 'next-generation engine' as the Source engine is always updating and is just as relevant in the gaming world today if not more than when it debuted in 2004. It has been aided by the release of the free Source Development Kit (SDK) which include such features as HDR for developers to use in their projects. Hence the reasons stated we have yet to see 'Source Engine 2'.

On July 10th 2012, Valve released the 'Source Filmmaker' - a freeware client to allowed anyone to make movies inside the Source Engine. More information on the Source Filmmaker can be found here.

Below you can find a list of amazing features that the Source Engine boasts:


  • Version 2.0 (and below) shaders, bump mapping, LOD on models and world
  • Author shaders with HLSL
  • Cube and environment mapping
  • Dynamic lights, vertex lighting and light maps, many light types including flickering, pulsing etc.
  • High-Dynamic Range lighting
  • Water with refraction and fresnel effects
  • Advanced particle system that can emit sprites or models
  • Projected 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
  • Effects include but are not limited to: particles, beams, volumetric smoke, sparks, blood, environmental effects like fog and rain
  • Scalability
  • Dx6-Dx9 hardware supported

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 based 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 naturally speak in many languages
  • Skeletal/bone system for animation
  • Layered animation system can synthesize complex animations out of several pieces
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Blog RSS Feed Report abuse Latest News: Devblog #44

About INFRA with 3 comments by assassini on Dec 12th, 2014

Hey guys. You've probably noticed the IndieDB Indie of the Year competition that has been going on for a week or so. The top 100 was announced three days ago, and we were in there! And that's because of your votes! It's awesome and you guys are awesome.

The second phase of voting has begun and we're now competing for the title of indie of the year. We would appreciate it if you would vote for us again!

Anyways. This week we have a fresh(ish) piece of concept art from our friends over at Kraffit.

These screenshots, on the other hand, are from a level that Mikko has been working on.

We've also been working on a plethora of other stuff, but none quite made the cut into this week's devblog. I guess this will have to do.

Media RSS Feed Latest Video
Half-Life 2

Half-Life 2 Half-Life 2

Updated 4 days ago Released Nov 15, 2004 Single & Multiplayer First Person Shooter

Pick up the crowbar of research scientist Gordon Freeman, who finds himself on an alien-infested Earth being picked to the bone, its resources depleted...

Garry’s Mod 10

Garry’s Mod 10 Garry’s Mod 10

Updated 6 days ago Released Nov 27, 2006 Single & Multiplayer First Person Shooter

Garry’s Mod is a sandbox mod for the Source Engine. Unlike normal games there aren't any predefined aims or goals. Players are given tools and are left...



Updated 6 days ago TBD Single Player Puzzle Compilation

Those most overlooked are often the most important. INFRA puts you into the shoes of a simple structural analyst. Nothing more than a quiet desk jockey...

Lost Story: The Last Days of Earth

Lost Story: The Last Days of Earth Lost Story: The Last Days of Earth

Updated 1 week ago TBD Single Player First Person Shooter

Lost Story: The Last Days of Earth - a sci-fi action adventure first-person game. The story takes place in a world that is not yet destroyed by the Seven...

Silent Escape

Silent Escape Silent Escape

Updated 1 week ago TBD Single Player First Person Shooter

Silent Escape is a mod that takes place in the Half-Life 2 universe. In Silent Escape, scientists has organized the project of "Silent Escape" in which...

Post comment Comments  (70 - 80 of 317)
McKane Oct 25 2011, 12:32pm says:

The Source Engine 2008 really showed itself off in Left 4 Dead, the first one. The visuals and the edge smoothing is just amazing!

+3 votes     reply to comment
ProspectGames Oct 22 2011, 9:35am says:

Does anyone know how, or know of, a tutorial for exporting models from Maya to Left 4 Dead 2?

+2 votes     reply to comment
tschumann Oct 29 2011, 3:19am replied:

Export the model and animations as .smd files I think Valve may ship an exporter in the Source SDK, but I'm not sure) and create a .qc file and compile with studiomdl. There are tutorials on writing .qc files on the Valve Developer wiki.

+2 votes     reply to comment
WS-GS8 Oct 14 2011, 4:04pm says:

Why you break hammer valve? My Gmod map was almost done!

+3 votes     reply to comment
McKane Aug 14 2011, 12:21pm says:

The Source engine is the most powerful and most beautifully detailed engines I have ever come across, Valve should start making RTS games with a engine like this, since there aren't many about at the minute.

-2 votes     reply to comment
david3 Oct 19 2011, 6:57am replied:

agreed. rts games will look a lot more awesome with this engine.
just look at hl2:wars modification.

+3 votes     reply to comment
shadowdude1 Aug 15 2011, 5:01pm replied:

You are a typical gamer
More advanced people will never claim Source as one of most powerful engine

+10 votes     reply to comment
McKane Oct 25 2011, 12:39pm replied:

Shadowdude, don't forget this engine is 7 years old. I know it has been slightly modified over the years, and yes, the most powerful engine I have ever seen is CryEngine 3.

But the CryEngine 3 is 2 years old though. Also the size of Valve compared to EA is massive.

+2 votes     reply to comment
MartyrT Sep 13 2011, 12:44pm replied:

Most powerful? Oh, absolutely not! But very versatile, very modifiable, and one of the longest running engines out there! They used it for HL2 7 years ago and are still using it on the new Counter-Strike!

+5 votes     reply to comment Oct 9 2011, 3:28am replied:

and it still looks great

+3 votes     reply to comment
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Released Oct 31, 2004
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Highest Rated (16 agree) 10/10

Even tho it is aging and it is beginning to show its weakness comparred to other more modern engines, it is still my most preferred engine and the only one I was able to get into succesfully. And with all of the updates Valve is giving it, I think the source engine will be with us for a long time. I wouldn't really recommend this for a commerical product, just because there are so many more modern engines out there that will be a lot easier in the long run (like UDK), but all of the commercial games…

Nov 16 2010, 3:48pm by Half_Kill

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