Two Future AMD Features Are Debuting in PS4 Pro; Watch Dogs 2 & Mass Effect Andromeda Run @1800P
Eurogamer's Digital Foundry just posted a lengthy interview with the architect of Sony's PlayStation 4 Pro console, Mark Cerny. The huge article delves into plenty of technical details, but a few are particularly worthy of note.
The first one we've highlighted is that PS4 Pro sports not one, but two features that are on AMD's roadmap to be implemented in their discrete GPUs at some future point.
A few AMD roadmap features are appearing for the first time in PS4 Pro.
How it works is that we sit down with AMD, who are terribly collaborative. It's a real pleasure to work with them. So basically, we go ahead and say how many CUs we want to have and we look at the roadmap features and we look at area and we make some decisions and we even - in this case - have the opportunity, from time to time, to have a feature in our chip before it's in a discrete GPU. We have two of these this time, which is very nice.
One of the features appearing for the first time is the handling of 16-bit variables - it's possible to perform two 16-bit operations at a time instead of one 32-bit operation. In other words, at full floats, we have 4.2 teraflops. With half-floats, it's now double that, which is to say, 8.4 teraflops in 16-bit computation. This has the potential to radically increase performance.
Once a GPU gets to a certain size, it's important for the GPU to have a centralised brain that intelligently distributes and load-balances the geometry rendered. So it's something that's very focused on, say, geometry shading and tessellation, though there is some basic vertex work as well that it will distribute.
The work distributor in PS4 Pro is very advanced. Not only does it have the fairly dramatic tessellation improvements from Polaris, it also has some post-Polaris functionality that accelerates rendering in scenes with many small objects... So the improvement is that a single patch is intelligently distributed between a number of compute units, and that's trickier than it sounds because the process of sub-dividing and rendering a patch is quite complex.
He also proudly noted that even the reverse can happen. Such was the case with Asynchronous Compute: Mark Cerny was very passionate about it and Sony did a lot of work adding it to the original PlayStation 4. Asynchronous Compute then ended up getting incorporated into subsequent AMD GPUs and it's now of the main advantages AMD has over NVIDIA in terms of GPU architecture.
Cerny then explained that developers who are working on a PS4 Pro game can choose between two techniques that use the ID buffer to boost image quality: geometry rendering (which allows for crisper edges, detailed foliage and storm fences) and checkerboard rendering (which is more intensive but also brings increased detail in both textures and specular effects).
So far, nine of the first thirteen titles due to support PS4 Pro are going to use checkerboard rendering, including Watch Dogs 2, Mass Effect: Andromeda, Infamous: First Light and Killing Floor 2. These particular four will all run at 1800P (3200x1800) with checkerboard rendering.
There are, however, games like Paragon which merely add visual enhancements while the resolution will still be an upscaled 1080P on a 4K display. Cerny explained that going forward, Sony will encourage developers to seek higher resolution modes.
Going forward we are highly encouraging direct support for 4K TVs and HDTVs, though we leave the specifics of how they do that up to the development community. They know best, but we really do want to see a higher resolution mode for 4K TVs and then some technique for HDTVs. It can be just scaling down from a higher resolution.
Finally, the console has been packed with an additional gigabyte of DDR3 RAM that will be used to swap between games and other apps like Netflix while the remaining memory is used strictly for games.
PlayStation 4 Pro will be out on November 10th for $/€ 399 or £349 if you are in the United Kingdom.