While the general trend is that internet connections are getting faster and users are hobbled by fewer bandwidth limits, this isn't always the case. Some people are unlucky with the speeds of their connections due to location and others have their speeds/allowances limited by penny-pinching service providers. Whatever the cause, there is still a need to optimise remote game streaming to meet the quality demanded by end users while being thrifty with internet data requirements.
Yes, it's the 2004 vintage Doom 3 in a 'high-end gaming' demonstration video
In a newly published video and blog post Due University outlines research it has been undertaking with Microsoft to bring high-end games to smartphones and tablets "without guzzling gigabytes". A tool called 'Kahawai' (the Hawaiian word for stream), is said to deliver graphics and gameplay "on par with conventional cloud-gaming setups for a fraction of the bandwidth".
83 per cent less bandwidth required
The key feature of Kahawai is its 'collaborative rendering' functionality. In traditional cloud gaming remote servers compute all the game's 3D graphics and pipe them back to the local device. With collaborative rendering that load is lightened significantly by letting the local device's GPU do some of the work. Specifically the Duke University blog says that "collaborative rendering lets the mobile device generate a rough sketch of each frame, or a few high-detail sketches of select frames, while the remote server fills in the gaps". This results in a game with the same visual quality requiring just a sixth of the bandwidth.
Duke University and Microsoft researchers tested the new collaborative system with "50 hardcore gamers". The guinea pigs said they felt no difference in response times between Kahawai and traditional streaming and this was seen in the performance metric of gaming scores achieved. The researchers added that Kahawai can even allow games to play when the internet connection is lost, albeit with less good quality graphics. The technique can be used for both games and serious 3D applications.
Xbox One example
A couple of years ago, when we first started to hear news about the Microsoft Xbox One, we carried a news story about Microsoft cloud servers shouldering the responsibility to render 'latency-insensitive' graphics for the console. This is a technique that sounds like it is based on the same ideas and is similarly thrifty upon network demands as the new Kahawai research.
From reading around it seems like this facility has been used to improve the graphics in Titanfall on the Xbox One. Other than that, talk about the rendering of latency insensitive graphics using Microsoft's Azure cloud in shipping games is pretty thin on the ground.