Newsgroup: it.comp.giochi.action
Titolo: DirectX 12's new rendering features are coming to DirectX 11.3 too.

At this year’s Intel Developer Conference and Nvidia’s Maxwell Editor’s 
Day, Microsoft were busy banging the DirectX 12 drum. They were 
demonstrating its CPU efficiency boosts as well as talking up the new 
rendering features they’re implementing to show off the latest GPU 
hardware around.
 
Microsoft also announced the new rendering features are also going to 
be part of the DirectX 11.3 API, which is being shipped at the same 
time as DirectX 12. That sounds great, but it also fills me with fear. 
Back in 2007, DirectX 10 was exclusive to Vista, leaving popular 
Windows XP in the dust. The same thing could happen with Windows 7 and 
DirectX 12.
 
Microsoft wasn't talking about which versions of Windows DirectX 12 
would land on when it showed off the API, but it was talking about some 
impressive new features.
 
The principal development lead for Direct3D, Max Mullen, must have 
thought I was stalking him. Sat in the front row for his talk at IDF in 
San Francisco, I was scribbling down notes about frighteningly complex 
coding paths that my feeble mind could scarcely compute, and then the 
following day I’d tracked him down to Monterey at Nvidia’s Editor’s Day 
covering the new Maxwell graphics cards.
 
The new DirectX 12 API is set to really revolutionize the way 
developers code their games for the PC. The improvements to CPU 
overhead efficiency and boosted scalability across multiple cores are 
going to do great things for us folk with multi-core processors 
(y’know, all of us) and that’s something Intel itself is eager to 
support.
 
Speaking to Intel representatives last week they told me: “It used to 
be pretty difficult to do multi-threading. It's been what, ten years 
now, we've been trying to drive multi-threading. The tools are a lot 
easier now, it's a lot easier to manage the different things going on 
in codes. DX12 is structured to allow easier segmentation of your code 
so that you can do multi-threading.”
 
DirectX 12’s efficiency benefits are going to do great things for small 
form factor machines (a growing segment in PCs) and mobile gaming too.
 
The balancing act that DX12 can do between CPU and GPU load, 
demonstrated by the asteroid demo Intel and Microsoft were showing at 
both SIGGRAPH and IDF, means that the API is able to determine when the 
GPU needs the most power and can cut back the CPU when it’s not being 
needed.
 
This means you can dial back the CPU cooling as the chip’s not being so 
heavily used, greatly reducing fan noise, and that also means in the 
mobile world your processor isn’t chewing through your precious battery 
life so quickly.
 
At Nvidia’s Editor’s Day though the focus, obviously, was on graphics 
performance. In particular on a set of new rendering techniques that 
are being introduced to the next generations of the Direct3D family of 
APIs.
 
http://media.pcgamer.com/files/2014/09/New-rendering-features.jpg
 
 
McMullen introduced four new rendering features - rasterizer ordered 
views, typed UAV load, volume tiled resources and conservative 
rasterization. The reason these were being first spoken about at an 
event demonstrating Nvidia’s latest graphics architecture is because 
they link directly in with new graphical effects they’re both hoping 
developers take on board.
 
The first technique, rasterizer ordered views, is very much like the 
Direct3D extension Intel introduced last year, Pixel Sync. They both 
allow for order independent transparency, a tricky thing to reproduce 
in real-time gaming, and that means we’ll get cheaper and more 
effective blended textures and complex transparent objects - hopefully 
including smoke effects.
 
Volume tiled resources and conservative rasterization both lead into 
the new voxel-based lighting system, VXGI (Voxel Global Illumination), 
that Nvidia has introduced with their new Maxwell GPU architecture.
 
That’s a method of lighting a scene based on light rays bouncing off 
surfaces. To be able to function in real-time on a GPU it only 
calculates the first bounce, but it leads to incredibly accurate 
lighting models.
 
VXGI looks like being an important step on the path to genuine 
real-time ray-tracing.
 
It was first researched by Nvidia engineers back in 2011, but with the 
combination of work Microsoft has been doing with Direct3D 12 and the 
new hardware acceleration that the GTX 980 is going to enable, it’s 
finally going to be usable on a desktop PC rather than a hulking great 
workstation.
 
The image is converted into voxels to quantify the lighting data that 
passes through the 'boxes'
 
http://media.pcgamer.com/files/2014/09/Apollo-Voxel.jpg
 
 
Once the voxel calculations are complete the final scene has much more 
realistic lighting
 
http://media.pcgamer.com/files/2014/09/Apollo-VXGI.jpg
 
 
VXGI basically converts a scene into voxels, surrounding the images in 
large boxes, and then calculates how light moves and reacts through 
those boxes. The twin benefits of volume tiled resources and 
conservative rasterization allow this voxelisation of a scene to be 
done quicker, cheaper and with a greater degree of accuracy.
 
This voxelisation isn’t actually rendered out to the display though, so 
you wont see Witcher 3 rendered as a set of boxes for example, but it 
will use the lighting data to create incredibly accurate lighting 
models.
 
These new features aren’t restricted to DirectX 12 though.
 
“The reason we’re doing this really is Direct3D 12 is an awesome 
improvement in the ability to render rich, immersive scenes with lots 
of objects,” explained McMullen, “but not every game actually needs the 
CPU overhead reduction or the scalability across cores. Direct3D 11 has 
been, and is, a great API for a large number of games, and will be for 
the next few years.
 
"If you’re not CPU limited, chances are you are GPU limited. If you 
look at the history of hardware features, they tend to do two things. 
They either enable new scenarios that were never possible before, or 
they greatly increase efficiency in what you’re already rendering. 
That’s exactly why we’re bringing these new rendering features to 11. 
If your game still fits the CPU profile of D3D11, but you need more GPU 
perf you’ll get it with the new hardware features.”
 
So we’ll get all this new graphical goodness dropped into DirectX 11.3 
when that’s released alongside DirectX 12 next year. On the surface 
that sounds great and fingers crossed it’s only happening so existing 
DirectX 11-coded games will be able to leverage their benefits.
 
But my concern is that it will more easily enable Microsoft to limit 
DirectX 12 support to either Windows 8 or 9, cutting out the hardcore 
Windows 7 fans, in order to encourage them to upgrade.
 
If Windows 7 is limited to DirectX 11.3 with DirectX 12 being 
restricted to later versions of Microsoft’s operating system there’s 
going to be a lot of upset PC gamers out there.

 hardware around.
 
Morale della favola, useranno le 12 per spigne win 9. Ci schiafferanno 
dentro una paio di ficiurz implementate male e che si potevano fare 
benissimo con l'11 per piare solita percentuala vendite da Merdasoft.
Same old story