Achieving Retina

To make the MacBook Pro’s Retina Display a reality Apple had to work with panel vendors to build the panels it wanted at a reasonable cost, as well as deliver the software necessary to support insanely high resolutions. There was another problem Apple faced in making the rMBP a reality: the display pipeline of the GPUs Apple wanted to use didn't officially support scaling to the resolution Apple demanded of them. Let me explain.

All modern GPUs have fixed function scaling hardware that is used to efficiently scale between resolutions. A scaler either in your GPU or in your display panel is what lets you run non-native resolutions at full screen on your LCD (e.g. running 1680 x 1050 on a 1920 x 1080 panel). None of the GPUs used in the Retina Display MacBook Pro officially support fixed-function scaling of 3840 x 2400 or 3360 x 2100 to 2880 x 1800 however. Modern day GPUs are tested against 2560 x 1440 and 2560 x 1600, but not this particular 5MP resolution. Even 4K resolution support isn’t widespread among what’s available today. Rather than wait for updated hardware and/or validation, Apple took matters into its own hands and built its own GPU accelerated scaling routines for these higher resolutions. Fixed function hardware is almost always more efficient from a performance and power standpoint, which is why there’s some additional performance loss in these scaled resolution modes. 

What’s even crazier is Apple wasn’t pleased with the difference in baseline filtering quality between the Intel HD 4000 and NVIDIA GeForce GT 650M GPUs. As the Retina Display MacBook Pro would have to regularly switch between GPUs, Apple wanted to ensure a consistently good experience regardless of which GPU was active. There are a lot of filtering operations at work when doing all of this resolution scaling, so rather than compromise user experience Apple simply wrote its own default filtering routines. Since you want your upscale and downscale quality to be identical, Apple had to roll its own implementation on both. Apple’s obsessive attention to detail really made it possible to pull all of this off. It’s just insane to think about.

The Software Side of Retina: Making it All Work Driving the Retina Display: A Performance Discussion
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  • Manni01 - Tuesday, July 17, 2012 - link

    Great review as usual, but I would really like to know how Anand was able to check if Speedstep and Turboboost worked. In the last Macbook review (2011), he used MSR Tools, but I could not get these to work on Lion on my June 2012 MBP 13. He remains very vague about how, although he does confirm this works as expected on the MBP 15r .
    This isn't my experience. I tried using Intel's MacCPUID in Lion, and a few other tools, and it looks like the CPU is locked at nominal speed (2.9GHz in my case), so neither speedstep nor Turboboost seem to work in Lion. They work as intended in Win7/Bootcamp, going down to 1GHz to save battery or up to 3.6GHz when only one core needs more power.
    So here are my questions:
    1) Anand please could you tell us which tools you have used?
    2) Has anyone tested this on the new macs (June 2012), using which tools, and what is the result?
    Speedstep definitely worked in Snow Leopard on my MBP 13 2011, so it must be a limitation in Lion.
    Reply
  • kenancagri - Thursday, July 19, 2012 - link

    It is very good article. I loved it. Thanks for Lal Shimpi. Reply
  • williamsj - Friday, July 27, 2012 - link

    Even the iPhone 4 is physically easier to maintain/upgrade than this thing.

    Check http://www.ifixit.com

    The worst maintainable piece of hardware they have ever looked at!!

    John
    Reply
  • Throckmorton - Tuesday, August 07, 2012 - link

    You didn't address whether pixel doubling is supported for games. IE rendering each pixel as 4 screen pixels. That's very different from upscaling, because with pixel doubling there's no blurring. Reply
  • Dubious1968 - Thursday, August 09, 2012 - link

    I've given up waiting for Apple to refresh the iMac, and am thinking of buying the Macbook Pro Retina instead. My only concern is that Apple should have equipped this laptop with a more powerful graphics card, given it is driving such a high res screen.

    I will be using it for Photoshop and HD video editing along with some gaming.

    Any help appreciated.

    Dubious
    Reply
  • sleddoggin - Saturday, August 11, 2012 - link

    So, I've done my best to read (skim) through all 46 pages of comments for this post, and have been reading other threads on more-or-less the same topic, so forgive me if I've missed something.

    I own a base model rMBP w/ 16mb ram (for safety), and am really quite unimpressed by openGL performance in games that were fluid (30-60fps ANYway) on my old Mac Pro 2006 w/ an ATI Radeon 5770 HD graphics card (I guess it helps, too, that the Mac Pro GPU is sitting in an x16 PCIe lane, not an x8, as with the rMBP). The Mountain Lion upgrade has been some improvement.

    When I first read Anandtech's article, I sort of thought, why not shut the lid on my MacBook Pro Retina, and plug in my old Apple Cinema display when I want to play games (I plan on using my desktop display when I'm at home for most stuff anyway). Then, the discreet NVIDIA GeForce GT 650M wouldn't be overworked by having to render all those extra pixels, right? Wrong. Gauging from the tests I've done, anyway, I'm getting the same choked performance on my relatively low-res external display (with the rMBP lid shut) as I do when I play those games on the rMBP screen (either at native OR scaled resolutions).

    So my question becomes, isn't this a software issue? Shouldn't the Apple/NVIDIA engineers be able to re-route ALL of that sexy mobile GPU processing power to a single, lower-res external display, and save us gamers the hassle of trading in our rMBPs for regular 2012 MBPs?

    This computer upgrade is really a no-brainer for me, otherwise. With the Thunderbolt ports, and the built in HDMI, I've been easily able to retire my old Mac Pro, and still keep my various displays (HDTV, etc.), and extensive array of USB/Firewire accessories fully operational. It just blows my mind that I get better gaming performance from my creaky old 2006 Mac Pro.

    Thanks for reading my contribution to this thread. Does my thought hold ANY water? I sure as heck don't want to give up this beautiful-looking piece of hardware if I don't have to...

    Cheers,
    -SledDoggin' (another reluctant Apple fanboy)
    Reply
  • vml_ - Saturday, August 25, 2012 - link

    Here's what I don't get and haven't seen answered anywhere. If there are performance issues at 1800p, can they be alleviated by downscaling (eg to 1080p)? Reply
  • S J - Friday, August 31, 2012 - link

    That sounds like great. good effort. Also have seen nice article on http://techinlead.com/apple-introducing-macbook-pr... Reply
  • LookupOEM - Saturday, September 22, 2012 - link

    maybe i'm wrong, but i always thought that OEM means "Original Equipment Manufacturer", a company that makes equipement that is sold by others under their own name.

    Toshiba making hard drives for Apple makes it an OEM, just as Intel, Samsung and others

    but, Apple IS NOT AN OEM, and there is no such thing as a PC OEM !!
    a PC OEM would be a company that supplies parts to build a PC, not the PC maker itself.

    did i miss something here ?
    Reply
  • Penzi - Thursday, October 04, 2012 - link

    Now that Mountain Lion has been out for a bit and several programs have been "retinized" are you planning on updating your review or crafting a mini-review that addresses changes, improvements and new caveats? I, for one, would love to hear about scrolling performance and resolution impact to common software (the OS and iWorks, FinalCut, etc), such as setting the display to "more space" (1920) and clocking the Safari FB news feed, and so on... Reply

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