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SMS dev discussing Shift 2 and upcoming pc patch

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http://www.nogripracing.com/forum/showt ... p?t=248847

Read replies to questions at NoGrip, but here's his introduction:

Hi,

My name is Martin Griffiths and I'm PC Lead on SHIFT 2 Unleashed. I'm

going to use this post to give you some background on our engine and

what's coming up in the first patch.

SHIFT 2 has a completely new engine which is a deferred, light pre-pass

renderer. A basic overview of this rendering method can be found at

http://en.wikipedia.org/wiki/Deferred_shading .

Our deferred renderer is far from basic though - the rendering team at SMS

has about 100 man years of render coding between us, and we used some

of the most advanced techniques that are known at this time. We did our

best - so it's sometimes disappointing after so many late nights to see

flippant remarks, over constructive criticism.

So, this new engine allowed us to do cool things such as the night racing that

would have been very difficult with an old style forward renderer. With

deferred rendering the lighting stage is separate from the geometry stage(s)

and hardware anti-aliasing like MSAA in a basic form won't produce correct

results. Solutions to allow us to anti-alias had to be found - we came up with

two methods to balance AA processing cost/quality over a wide range of

PCs. A very large amount of time was spent on this and while some other

developers just choose to do a post-pass edge detection filter we weren't

satisfied with that, the 'HIGH" method for example was 3 months of R&D.

There are lots of 'tips' about overriding the AA mode - doing this will produce

problems with lighting at edges and will also break other lighting components

like Bloom, giving a visual look that we didn't intend. If you prefer the look

with a driver over-ride then we've no problem with that - but the graphics

team wanted a consistent look and feel, to do the many artists who created

the tracks and cars justice.

There has been some confusion that our anti-aliasing uses the CPU - it does

not. In the graphics options the 'Normal' mode uses MSAA with a special

sampling trick to produce correct results at triangle edges - the 'HIGH'

method extends this with a depth based search which requires a GPU with

high bandwidth because the shaders are sampling many depth pixels for

each pixel in the scene. Any performance issue on particular hardware is

down to the characteristics of that GPU - there isn't anything we can do

about this without a driver update.

To better balance very high-end CPUs the patch will include a 3rd anti-aliasing

method which is CPU based - MLAA. We are working with Intel R&D to add

this. On quad-core (and above) systems this will allow AA without any GPU

cost and little impact to the frame rate to what you see when running with

AA turned off currently. This will also help AMD based quad-core too.

Some people have noted that the game doesn't scale well with SLI/Crossfire

- SLI performance scaling doesn't just automagically happen, it requires quite

close collaboration with the GPU makers. We've been in regularly contact

with NVidia and ATI throughout the development of the game, with their

performance teams feeding back on any areas where we could improve,

pooling our expertise with theirs. About 6 weeks of programmer time was

spent pre-shipping on SLI/Crossfire scaling - we needed another 4 weeks

since we went gold because of the complexity of implementing this in such a

large engine. Both GPU makers have devoted a lot of time to some complex

issues.

So yes, the upcoming patch includes SLI/Crossfire scaling. To give you an

example a GTX 295 will go from 48fps to nearly 70fps in 1080p. Also the

rendering team found some further optimizations so that normal (non SLI)

graphics performance should be 5-10% faster with the patch.

Input lag - we've solved the latency issues reported using some wheels.

There was a dead-zone issue and a threading problem introduced very late

in development that have been fixed.

Garage screen crashes/CTDs - a fast button press issue that wasn't seen

during development is also fixed in the patch.

A black screen issue on starting a race requiring a pause/unpause to fix is

also addressed. This was caused by a timing difference with the protection

system.

NVision - some reverse/double stereo issues with the mirrors and

environment maps have been addressed in the patch. NVidia very kindly

provided us with more hardware for the render team to address this - Kudos

to them for that.

There are also some more minor fixes in the patch - the above represent

the vast majority. If you have any specific questions, please feel free to ask

in this thread and I'll do my best to reply.

Regards,

Griff

--

Martin Griffiths, PC Lead, SHIFT 2 Unleashed, Slightly Mad Studios.

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Hello Martin,

Thanks for the info,...looking forward to the patch. I was only really concerned with the steering wheel

latency issues with my G27, as for the rest it did not really bother me as I us the PS3 version of the game.

Although the head movement in helmet cam, forward and back only, could be slightly less....apart from that,.. awesome game and will enjoy it even more when the steering wheel latency is fixed.

kind regards

Old Timer

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Ian Bell said they will send the patch to EA next week (April 24th-30th)

But EA must approv the patch, then send it to MS and Sony for certification too.

theoretically it may be faster for PC.

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