The game might be called Defense of the Ancients, but Valve is using the most cutting edge tech in its free-to-play MOBA game. A beta DLC pack was released yesterday that brings the Vulkan API to DOTA 2.
The Kronos Group released the open source Vulkan API in February with the promise of better graphics performance. In the three months that Vulkan has been available, there have been several announcements about various levels of support for the API. Nvidia added Vulkan support to its GeForce drivers, AMD added Vulkan support to the Radeon Software Crimson driver suite, and there’s a beta driver for Intel HD graphics. Imagination added Vulkan support to its PowerVR SDK, and Kishonti announced it updated GFXBench 5.0 with Vulkan support. And two weeks ago, Nvidia released a 6-minute long clip of Doom using Vulkan instead of OpenGL.
Doom was shown running Vulkan, but support for the API has not been released to the public yet. To our knowledge, Valve’s update for Dota 2 makes it the first game currently available to the public with Vulkan support.
To play Dota 2 with Vulkan enabled, you’ll have to opt-in to the Steam Client Beta to get the Steam Vulkan Overlay. The Vulkan DLC update can be found in the DLC tab of the game properties. Dota 2 won’t automatically launch with Vulkan enabled, even when the DLC is installed. You have to edit the launch parameters to include "-vulkan." Valve said that launch options for DirectX and OpenGL must be removed if present.
Valve said that it is aware of a few bugs. You may experience stuttering graphics the first time the game is run with Vulkan. Valve said this occurs when the engine is caching shaders to the disk drive, but it should affect only the first match you play or spectate. At least one person has reported seeing flickering shadows after enabling Vulkan. There is also a known issue with Linux and Nvidia GPUs that causes tearing when Vsync is enabled. Valve said Nvidia is working on a fix that will come in a future GPU driver update.
The Vulkan DLC Beta is already available to try.