Back in 2004, Valve Software released two games based on a new engine: Half-Life 2 and Counter-Strike: Source. Both became instant classics that are still loved today, and Source, the engine powering the games, went on to be used in a number of third-party games such as the recently-released Titanfall, NeoTokyo, Dark Messiah of Might and Magic and SiN Episodes. Valve titles that depend on the Source engine include the Left 4 Dead series, the Portal games and more.

For a long while we've wondered when Valve would finally release the second generation Source engine. That day finally came this week during the Game Developers Conference 2015. The company not only revealed the new engine, but announced that it will support the Vulkan API and be completely free for content developers.

"With Source 2, our focus is increasing creator productivity. Given how important user generated content is becoming, Source 2 is designed not for just the professional developer, but enabling gamers themselves to participate in the creation and development of their favorite games," said Jay Stelly, Valve's Senior Engineer. "We will be making Source 2 available for free to content developers. This combined with recent announcements by Epic and Unity will help continue the PCs dominance as the premiere content authoring platform."

The news arrives after Epic Games announced earlier this week that Unreal Engine will now be completely free to use, with no monthly subscription fee required. The catch is that Epic requires a 5 percent royalty fee after the resulting product -- whether it's a game or an animated film -- brings in $3,000 per quarter. Previously, developers were required to shell out $19 per month to use the highly-popular game engine.

In addition to Epic Games and Valve Software, Unity Technologies also made an engine-related announcement during GDC 2015 on the release of Unity 5. This engine is served up in two flavors: Professional Edition and Personal Edition. With the Professional Edition, game studios big or small, will be required to pay $75 per month, but the cost will include Unity Cloud Build Pro, Team License, Game Performance Reporting, Asset Store Level 11 and more. As for the Personal Edition, this version is aimed at hobbyists and new studios building their first game; this version is provided for free.

"Unity 5 is a massive step up for Unity that empowers developers to make more beautiful and intricate games that reach bigger audiences, across more platforms," said John Riccitiello, CEO of Unity. "We want everyone to have access to Unity 5 which is why we've increased the value of our royalty-free licenses. Unity 5 Professional starts with the power of Unity 5.0 and adds valuable tools such as Unity Cloud Build Pro and Team License. Unity 5 Personal Edition is for the developer just getting started and offers all the power of the engine and editor for free."

As for Valve's Source 2 engine, there's now speculation that Half-Life 3 may be announced soon. Of course, that rumor has been around since the dawn of time, but with the new engine unleashed, there's a good chance the third Half-Life installment won't be too far behind. Valve could possibly announce the game sometime during the E3 2015 time frame, but that's just a hopeful guess.

As of this article, Valve has not released any information about when the Source 2 engine will be available. However, in a press release, Valve elaborated a bit more on Source 2's support for the Vulkan API, which was just revealed this week during GDC.

"Also as part of supporting PC gaming, Valve announced that it will be releasing a Vulkan-compatible version of the Source 2 engine," reads Valve's press release. "Vulkan is a cross-platform, cross-vendor 3D graphics API that allows game developers to get the most out of the latest graphics hardware, and ensures hardware developers that there is a consistent, low overhead method of taking advantage of products. Vulkan, previously called Next Generation OpenGL, is administered by the Khronos Group, along with other standards such as OpenCL, OpenGL, and WebGL."

What an exciting year this will be for PC gamers!

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