So the PDF for NEO was leaked and is available here:
https://www.scribd.com/doc/312585554/PS4-5-NEO-pdf
Some tidbits:
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Prototype Hardware Returns
To begin at the start of 2017
Mass-produced units will be available prior to prototype returns, but release timing is still TBD
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Single package for Original/NEO Systems
PS4 SDK supports both original PlayStation®4system and NEO system
CPU Binary can run on both systems
– /app0/eboot.bin in the package must be shared for Base Mode and NEO Mode
– Sharing other CPU binaries is game developer’s choice.
– sceKernelIsNeoMode() reports whether title is running NEO mode (so you can change the behavior of the title.)
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NEO Support with SDK 350
One strategy for NEO game development is to detect the resolution of the connected TV, and
– Prepare a 1920x1080 display buffer when an HDTV is connected
– Prepare a 3840x2160 display buffer, usually using an efficient rendering
technique such as “checkerboard rendering,” when a 4K TV is connected
– Ensure that the NEO frame rate meets or exceeds the frame rate of the game on the original PlayStation 4
SDK 3.500 is designed with this strategy in mind
We will support other strategies as well; the next few pages describe a few of them.
However, we understand that you know your game best and we are happy to engage in conversations about strategies that work for the game but still deliver a great NEO experience for the player.
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Lower resolution strategies
Some developers have reported that in order to keep the frame rate of the NEO version above that of the original PlayStation®4, the resolution of the display buffer must be reduced.
In “debug mode,” display buffer resolutions of
3680x2070, 3520x1980, 3360x1890 and 3200x1800 are also supported. You can use one of these, or use an MRT resolution of your choice (e.g. 3200x2160) and scale the final image to one of the supported resolutions. Future SDKs will officially support a broad variety of resolutions.
To recap, with this strategy, the title might
– Prepare a 1920x1080 display buffer when an HDTV is connected.
– Prepare a 3520x1980 display buffer when a 4K TV is connected; NEO will then upscale the image in hardware before outputting to the TV.
– As with all strategies, it is important to ensure that the NEO frame rate meets or exceeds the frame rate of the game on the original PlayStation®4.
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Single mode strategies
Some developers would like to have one mode of NEO support rather than two.
Though work is just beginning in this area, some developers are reporting success in creating just a single resolution (e.g. 3520x1980) and scaling it down to 1920x1080 for output to HDTVs
Though SDK 3.500 does not support this type of downscaling, future SDKs will allow it. For SDK 3.500, you will need to scale down the display buffer in your game engine.
To recap, with this strategy, the title might
– Prepare a 3840x2160 (or other) display buffer
– When connected to an HDTV, scale the image to 1080p before outputting (though future SDKs will accept the image without scaling)
– When connected to a 4K TV, output the image as normal
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Lower resolutions
Our experience is that using lower resolutions for 4K TV support (such as 1440p) does not create much differentiation from 1080p on an HDTV.
Our hope is that titles will use checkerboard rendering (and similar techniques) to allow for resolutions much closer to 2160p.
We are currently researching lower-cost techniques for increasing resolution (such as the geometry rendering described in the original disclosure meetings.) If you are having difficulties achieving resolutions above 1800p, please do contact your regional Developer Technology Group so we can share our latest learnings.