The first output of AMD’s initiative is LiquidVR™, a set of innovative technologies focused on enabling exceptional Virtual Reality content development for AMD hardware, improved comfort in VR applications by facilitating performance, and plug-and-play compatibility with VR headsets. The upcoming LiquidVR SDK makes a number of technologies available which help address obstacles in content, comfort and compatibility that together take the industry a major step closer to true, life-like presence across all VR games, applications, and experiences. In virtual reality, the concept of ‘presence’ is described as the perception of being physically present in a simulated, nonphysical world in a way that fully immerses the user.
A key obstacle to achieving presence is addressing motion-to-photon latency, the time between when a user moves their head and when his or her eye sees an updated image reflecting that new position. Minimising motion-to-photon latency is critical to achieving both presence and comfort, two key elements of great VR. Reducing latency involves the entire processing pipeline, from the GPU, to the application, to the display technology in the headset. AMD GPU software and hardware subsystems are a major part of improving that latency equation, and with LiquidVR™, AMD is helping to solve the challenge by bringing smooth, liquid-like motion and responsiveness to developers and content creators for life-like presence in VR environments powered by AMD hardware. Basically – you won’t need to worry any more about motion sickness when using VR technology, which is great considering that it was a major issue for the original Rift headset! AMD have released the alpha version of LiquidVR SDK 1.0 to registered developers.
Significant features of version 1.0 of the LiquidVR SDK include:
- Async Shaders for smooth head-tracking enabling Hardware-Accelerated Time Warp, a technology that uses updated information on a user’s head position after a frame has been rendered and then warps the image to reflect the new viewpoint just before sending it to a VR headset, effectively minimising latency between when a user turns their head and what appears on screen.
- Affinity Multi-GPU for scalable rendering, a technology that allows multiple GPUs to work together to improve frame rates in VR applications by allowing them to assign work to run on specific GPUs. Each GPU renders the viewpoint from one eye, and then composites the outputs into a single stereo 3D image. With this technology, multi-GPU configurations become ideal for high performance VR rendering, delivering high frame rates for a smoother experience. Latest data latch for smooth head-tracking, a programming mechanism that helps get head tracking data from the head-mounted display to the GPU as quickly as possible by binding data as close to real-time as possible, practically eliminating any API overhead and removing latency.
- Direct-to-display for intuitively attaching VR headsets, to deliver a seamless plug-and-play virtual reality experience from an AMD Radeon™ graphics card to a connected VR headset, while enabling features such as booting directly to the display or using extended display features within Windows.
AMD FreeSync™ technology
You know when you’re playing a game and you hear a noise and turn around as quickly as possible, only for the game world to stutter and tear as you look and ruin the experience? Well, FreeSync is here to get rid of that. No stuttering. No tearing. No extra costs. Just smooth gaming. Those are pretty straightforward and reasonable requests from gamers, right? Today it becomes reality with the latest AMD Catalyst™ driver release.
Here’s another interesting fun fact: testing indicates that AMD FreeSync technology doesn’t incur any performance penalties. For Twitch.tv FPS gamers – AMD heard you guys loud and clear: Vsync isn’t enough. Streamers don’t want it because it limits framerates, and that limits opportunities for the freshest mouse data to reach your eyeballs. Call it what you will: mouse lag, input latency, whatever. With AMD FreeSync™ technology, AMD uniquely gives you the opportunity to turn Vsync off when the framerate of the application leaves the dynamic refresh range supported by the monitor.
So, if you have one of those 144Hz BenQ or Acer displays, but you’re a Counter-Strike: Global Offensive player that wants to run at 240 FPS… you can! You still get beautifully smooth, tearing-freegameplay from 40-144Hz with those monitors, but you don’t have to sacrifice your input latency to get it when the framerate goes to 145+.
Below you can see a conceptual example of this relationship. In this theoretical exercise, the red line reflects framerates and input latency of an application Vsynced to 60Hz, and the blue line demonstrates the superior framerates and mouse latency of a game unrestricted by Vsync. This is a hypothetical scenario, and you’ll want to tinker with your favourite game, but AMD FreeSync actually gives you the choice—the competition doesn’t.
The major goals and benefits of AMD FreeSync™ technology are:
- Dynamically adapt display refresh rate to variable gaming content update rate for low latency and
stutter-free gaming experience.
- Dynamically adapt display refresh rate to a fixed video content update rate for stutter free video
- Ensure that the transition between refresh rates is seamless and undetectable to the user
- AMD FreeSync technology costs virtually nothing for a monitor manufacturer to adopt.
AMD FreeSync technology is free of incremental hardware costs, free of performance penalties, free as a standard, open for use by anyone in the gaming industry, and unbelievably smooth framerates are I-can-never-go-back-to-the-old-way incredible for PC gaming.