March 30, 2012

Retina display Macs, iPads, and HiDPI: Doing the Math

Love Apple gear? Like math? TUAW’s Doing the Math series examines the numbers and the science behind the hardware and software.

The rumourmill has been busy lately with claims that we might get “Retina display” Macs soon — and of course, a Retina display iPad 3 on March 7, probably, maybe, definitely. For an example of the sort of speculation, consider Bjango developer Marc Edwards, who tweeted: “Retina 27″ Thunderbolt display: 5120×2880 = 14,745,600 pixels. 4K film: 4096×2160 = 8,847,360 pixels. Retina iPad 3: 2048×1536 = 3,145,728 pixels”. This prompted me to dust off my Retina display iPad post from a year ago and revisit the mathematics I applied there to dig a little deeper into what a Retina display Mac might entail. Is Edwards right — would a Retina display Thunderbolt display really need almost 15 megapixels?

Isn’t this all just marketing?

Before I launch into a long-winded diatribe (“surely not!” — everyone who’s ever read any of my other TUAW posts), I need to address a surpisingly common point of view. Some people say that as “Retina display” was a term Apple made up, it can mean whatever it wants it to mean. If Apple wanted to, the theory goes, it could just declare the current iPad to be a Retina display and be done with it.

I think this argument is asinine. Firstly, although Apple invented the term out of whole cloth, it does offer a definition: “the Retina display’s pixel density is so high, your eye is unable to distinguish individual pixels.” That has meaning, and if Apple were to weaselly dilute the definition for the sake of marketing some future product I think we should absolutely hold its feet to the fire.

Secondly, this isn’t just about Apple. High DPI screens are starting to appear on other devices, like this Android tablet from Asus. The precise phrase “Retina display” might belong to Apple but the advantages of high resolution screens do not. As this is an emerging trend across the whole industry, it behooves us to strip away the marketing pixie dust and take an objective look at what this technology can offer.

Defining “Retina display”

So what does it mean to say that a screen’s individual pixes are indistinguishable? The launch of the iPhone 4 and the first Retina display was, of course, accompanied by a jump in the screen resolution from 480×320 to 960×640 — from 163 pixels-per-inch (ppi) to 326 ppi. This in turn lead many people to label some arbitrary resolution as “Retina display” — typically 326 ppi itself, or 300 ppi. The latter number is a common rule-of-thumb baseline in the print industry for “photo resolution”.

It’s not that simple, however.

Hold a small-print book at arm’s length. Notice how it’s hard to read the text. Now bring the book up to a few inches from your nose. Notice how much easier it is to read now. Clearly, if Apple is defining a “Retina display” as “one where users can’t see the pixels” then any discussion of whether a given display qualifies or not needs to take into account the distance between the screen and the user — and that differs according to the device. An iMac on a desk, a MacBook in your lap, and a hand-held iPhone all have different viewing distances.

So, how do we determine how small a pixel has to be to be bordering on invisible? To answer this we need to think about subtended angles.

Consider the following scenario:

The viewing angle in this diagram, a, is called the angle subtended by the inter-pixel spacing, s. Whether or not a given detail is too small to be discerned by the eye is down to the size of this angle. This is how the size of an object is related to the viewing distance — as you move an object of a given size closer or further away from the eye, so the size of this angle changes. Conversely, at given distance, a larger object will also subtend a bigger angle. The size of the image on the retina is intrinsically derived from the object size and the viewing distance, linked by this formula:

So what subtended angle is too small to see? The average person has 20/20 vision. This was historically defined as the ability to read letters on a standard eye chart that subtend 5 arcminutes of angle (an arcminute is 1/60th of a degree). What does that mean in pixel terms? Consider that just about the smallest legible fonts, Tinyfont by Ken Perlin and Tiny by Matthew Welch, uses five pixels of height (including descenders for Tiny) for each letter. This suggests the smallest resolvable detail for an average eye is around one arcminute. Indeed, one arcminute is an accepted value amongst academics for the resolution limit of a typical human retina.

Retina-ness of Apple’s current displays

With the data above in mind, and applying the mathematics from my previous post, we can take some typical viewing distances for different Apple devices, combine it with the screen size and resolution, and calculate how close the screen comes to the definition of a Retina display we have arrived at above.

You can view a Google spreadsheet that shows the details of how this data is calculated.

Just for fun, I threw in a couple of non-Apple devices for comparison — a 50″ TV at a distance of six feet, playing back a BluRay and a DVD; and the announced Asus Transformer Prime Android tablet, which has a 1920×1200 display.

This table shows some things that surprised me.

Firstly, it shows that Apple’s definition of Retina display aligns quite closely with my mathematic derivation. The iPhone 4 screen at a typical distance of 11″ is just barely above the threshold for a Retina display. I believe this justifies my methodology.

Secondly, it repeats my previous conclusion that a pixel-doubled iPad running at 2048×1536 is easily enough definition to count as a Retina display — even at a 16″ viewing distance, which is on the close side from my experimentation with an iPad and a tape measure. Similarly, that Asus tablet is a Retina display too.

It also shows that many current Mac displays are a lot closer to Retina display levels than you might have thought. The 27″ iMac at a distance of 28″, a 17″ MacBook Pro at 26″, an 11″ MacBook Air at 22″ — these screens all have pixels small enough to border on invisible.

Furthermore, the 480×320 iPhone screen is notably worse than everything else Apple makes today, at 53% of a Retina display. Even the second-worst 1024×768 iPad screen has finer detail at 61%. The worst Mac display is the 24″ iMac at a distance of 28″, at which distance its pixels are one-third too large to be individually indistinguishable.

Finally, this also shows why BluRay looks so good. On a largish TV at a shortish distance (50″ at 6′), a 1080p image is at 92% of Retina level, whereas a DVD is a downright poor 36%.

There are two very important points here.

The first is that in order to achieve, or even handily exceed, the threshold for a Retina display, Apple does not need to double resolutions on most of its displays. Far from it. It would suffice to boost a 27″ Thunderbolt Display from 2560×1440 to something around 2912×1638.

The second point is that people shouldn’t get their hopes up for how much better a Retina display Mac would be compared to the current offerings. The iPhone 4 was a huge step forward from the iPhone 3GS mostly because the 3GS’s screen was comparatively poor. Existing Macs have much better screens to start with, so any improvement will be much more modest.

Looking beyond one arcminute

From the above, you might think that there is hardly any reason to Apple to change anything, because the benefits of higher resolution screens are so modest. But clearly HiDPI mode exists, and specialist medical imaging screens are between 508 and 750 ppi. What’s the benefit to these high pixel densities?

The answer is that our definition of the limits of human vision — details that subtend an angle of one arcminute — is rather simplistic. There’s a lot more to think about when considering how real human vision interacts with computer display technology, including atypical viewing distances, different sorts of patterns, and so forth. Reading words, for example, is possible at smaller sizes than reading random letters, because your brain has more context to guess at the characters. Your brain is a sophisticated pattern matching tool and it will use information from the surroundings to try and interpret details your eyes can’t quite make out clearly.

Here’s a number of test patterns for you to try this out on your own display. If you want to try this on an iOS device, you need to get the appropriate file for your device — iPhone or iPad — and save it to the Camera Roll. This is because iOS will helpfully try and zoom and pan images but we want to ensure that one pixel in the test image takes up one pixel on your display. Once you have them in the Camera Roll, view them full screen through the Photos app with your device in the portrait position. If you compare your Mac, iPad, and iPhone, you should see quite a difference in how well each screen performs.

The pixel doubling argument

Rene Ritchie for iMore makes a solid argument for why an iPad retina display must be pixel-doubled — i.e. 2048×1536 — and not some intermediate resolution (just as was the case for the iPhone 4 before it). Anything else means every single existing app either has to re-scale art assets — resulting in a fuzzy display — or let them appear at a different size on-screen — resulting in usability problems as the tap targets are resized. This is because every single existing iPad app is hard-coded to run full screen in 1024×768.

The situation is fuzzier on desktop, however. Apple’s current displays already vary between 92 and 133 pixels-per-inch. Users are more tolerant of UI element resizing, within reason.

Consider the 109 ppi 2560×1440 27″ Thunderbolt display, and let’s suppose Apple wanted to Retina it up. It could up the resolution to 4192×2358 — which works out to 178 ppi — and achieve a display with finer details than the iPhone 4. This is one-third less pixels than the native pixel-doubled resolution (which would be 5120×2880). UI elements would look proportionally larger — but no more than they do on the 24″ iMac display today, so it wouldn’t look clumsy or odd.

Wrapping up

Hopefully, I have convinced you of several things in this post.

  • “Retina display” carries more meaning than pure marketing.
  • The definition of what, and isn’t, a Retina display must consider viewing distance.
  • The improvement you’d see from a Retina dispaly Mac is significant, but less than the improvement the iPhone 4 offered over the 3GS.
  • A 2048×1536 iPad would be a Retina display and would look quite a bit better than the current model (but, again, be less of an improvement than the iPhone 4).

Still not convinced? Sound off in our comments!

I’d like to thank fellow TUAWers Brett Terpstra and Erica Sadun for helping me with the Retina Tester graphic.

TUAW – The Unofficial Apple Weblog

Daily iPhone App: Stack King lets you stack people, aliens and more for points

Ever watch a child stack blocks and wish you could do the same? If you like the precision of stacking, but don’t want to sit on the floor with a bunch of ABCs, then you should check out Stack King from Appy Inc.

As its name implies, Stack King is all about stacking. The first level starts out with a row of boxes that move back and forth across the screen. You must tap on the boxes to stop them in their place. Your timing must be impeccable as you want to stop each new row exactly on top of the previous one.

The better you line up your stack, the more points you earn. When the stack gets higher, the game gets increasingly challenging because your stack gets more narrow. It’s easy to stack four boxes on top of five boxes, not so easy to stack one on top of two. You continue stacking until you reach the end of the level or you miss and a box falls off the growing pile.

It’s a fast-paced game and wonderfully addicting. It’s also one of those games like Jenga that keeps you on the edge as you build your way to the top. One warning — the game does have a bouncy background track, so you may want to turn down the volume before firing it up in a crowded room.

If you’re tired of Temple Run and want something different, then you should check out Stack King. Stack King is perfect for those idle moments when you want a game that’s quick and easy. If you want more of a challenge, then you can compete for the top spot on the GameCenter leader board or find a friend for a quick pick-up game.

There’s only one thing I would change about Stack King and that would be the levels. I would love to see more! I’ve talked with the team at Appy Inc and they’ve promised me they have several new and challenging level in the works. Fingers-crossed they can roll them into an update soon.

Stack King is a universal app and available for free from the App Store. It’s a freemium game with a twist. You can earn your way through the levels or pay to advance. It costs US$ 0.99 for each level or $ 1.99 to unlock them all. You can also unlock a level if you share it with a friend and tell them about the game.

TUAW – The Unofficial Apple Weblog

New Intel Sandy Bridge Xeon chips available for potential Mac Pro update

By Daniel Eran Dilger

Published: 05:38 PM EST (02:38 PM PST)
Intel’s new Sandy Bridge update for its Xeon line of high end CPUs is due next week, suggesting the potential for Apple to refresh the Mac Pro, which hasn’t changed since the middle of 2010.

The availability of Intel’s latest Xeon E5 workstation-class chips next week was reported by British site The Inquirer.

The new Xeon E5 chips incorporate the Sandy Bridge micro architecture that first appeared in MacBook Pros and iMacs early last year, followed by a mobile variant used by Apple in the MacBook Air last summer.

Apple’s latest Mac Pro models currently use Intel Xeon Bloomfield or Gulftown processors based on the Nehalem and closely related Westmere microarchitectures.

The latest release of OS X 10.7.3 Lion included support for AMD’s high end Tahiti graphic cards, which are expected to arrive in the market around the same time as Intel’s new Xeon chips.

However, people famliar with the matter have said that Apple’s management, as far back as last May, were in limbo over whether to put any additional resources toward the Mac Pro product line.

Internal discussions at Apple were said to focus on the fact that sales of the high-end Mac Pro workstations have dropped off so considerably that the desktop machines are no longer particularly profitable for the company.


Briefly: Apple most admired; Tim Cook spotted in Paris; Motorola workaround

By AppleInsider Staff

Published: 09:40 PM EST (06:40 PM PST)
Apple has been named the “Most Admired” company for the fifth year in a row. Meanwhile, Apple CEO Tim Cook was reportedly spotted in Paris on business earlier this week. Finally, Motorola Mobility has responded to a recent injunction by a German court against it by noting that it has already implemented a workaround.

Most Admired Company

Fortune pronounced Apple as the most-admired company with a score of 8.42. Google placed second on the list of top 50 companies with a score of 7.74. EMC, the second-most-admired computer company, had a score of 6.78.

“To say it was another big year for Apple would be a gross understatement,” the magazine read. “With the passing of Steve Jobs, questions swirled around the company’s future. But under new CEO Tim Cook’s guidance, Apple continues to prosper.”

Apple ranked first in its industry for nine different “key attributes of reputation,” including innovation, people management, use of corporate assets, social responsibility, quality of management, financial soundness, long-term investment, quality of products/services and global competitiveness.

The publication’s most admired list is generated through a survey partnership with global management consulting firm Hay Group. The surveys ask executives, directors and analysts to rate companies for each of the attributes.

Cook in Paris

French Mac site MacBidouille (Translation) reported on Thursday that, according to one of its informants, Cook was in Paris earlier this week for a business trip of the “greatest secrecy.”

The report was unable to confirm the reason for Cook’s trip, but it speculated that he may have traveled to the city to sign a contract, since he would presumably have only made the trip if his physical presence was required. The publication added that it would not be surprised to learn that Apple had bought a company in France.

Motorola workaround

Shortly after a German judge issued an injunction against several Motorola devices for infringing on a photo gallery patent by Apple, the company issued a statement declaring that it has already implemented a way around the patent in question. As such, the company said it expects the injunction to have no impact on supply or sales of its devices.

“Today’s ruling in Munich, Germany on the patent litigation brought by Apple concerns a software feature associated with performing certain functions when viewing photos in a ‘zoomed in’ mode on mobile devices,” the statement read. “We note that the Court ruled that performing the functions in a ‘zoomed out’ mode does not infringe on this patent. We expect no impact to supply or future sales as we have already implemented a new way to view photos on our products that does not interfere with the user experience.”

However, Motorola’s statement contradicts earlier claims from patent expert Florian Mueller of FOSS Patents who said that any workaround by the company would “definitely degrade the user experience.”

The legal battle between Apple and Motorola has heated up in recent months after several victories on either side. Motorola has won injunctions against Apple’s implementation of push services, forcing its rival to announce to German customers that it has shut down iCloud push services in the country while it appeals the ruling.

Last month, Apple won an injunction against Motorola with its slide-to-unlock patent.

Motorola could also face an inquiry over its wielding of FRAND-committed patents against Apple. In order to submit patents to standards organizations, Motorola agreed to license some of its IP on Fair, Reasonable and Non-Discriminatory terms. Apple has complained to the European Commission that Motorola was unfairly using these standards-essential patents in its litigation.

Apple also appears to have taken some of the venom out of Motorola’s injunction threats by submitting a license offer to Motorola that has been accepted as reasonable by a German appeals court. Mueller called the victory a “breakthrough” for Apple, noting that the company’s appeal is “highly likely to succeed.” At this point, were Motorola to reject Apple’s offer, the appeals court could potentially label the action an antitrust violation.

Motorola had previously asked for a 2.25 percent royalty rate, but Apple balked at the figure. Pundits have labeled the rate unreasonable, given that other contributing companies asking for a similar rate would quickly eat up any profits from device sales.


Griffin announces StudioConnect Audio/MIDI interface for iPad

Musicians have another audio and MIDI interface to choose from when they’re looking for a way to connect a guitar, bass or MIDI instrument to an iPad. The new StudioConnect Audio/MIDI interface for iPad (US$ 149.99) was announced by Griffin Technology today, and it adds a sleek looking dock to the current options available.

StudioConnect can be used with the optional GuitarConnect Pro analog to digital interface ($ 79.99), Griffin’s Guitar Cables ($ 19.99), and the DJ Cable ($ 19.99) and a host of music applications on the iPad platform.

The video below shows the StudioConnect being used with Garage Band by musicians TJ Daly, Jaren Johnston and Katie Herzig. Several other videos are available here, showing Griffin employees demonstrating the StudioConnect with guitar, bass, and MIDI keyboard. It looks like a pretty cool accessory for the musically-inclined, and we’ll try to get a unit to our resident musicians for a followup review soon.

TUAW – The Unofficial Apple Weblog

Proview says no settlement negotiations yet with Apple over iPad trademark

By AppleInsider Staff

Published: 08:30 PM EST (05:30 PM PST)
Proview’s lawyer has revealed that the company is still hoping Apple will get in contact to begin out-of-court negotiations for a settlement in the ongoing legal disagreement over ownership of the Chinese iPad trademark.

The three-judge panel for the Higher People’s Court of Guangdong asked Proview and Apple whether they wished to settle during a hearing on Thursday, but, according to Roger Xie, Proview’s lawyer, Apple has yet to come to the table.

“Up to now, we didn’t have any formal negotiations with Apple,” Xie said in an interview. “I hope they will positively contact us and make an appointment with us about formal negotiations out of court. It would be useful.”

Earlier this week, representatives for Apple and Proview exchanged arguments in court. Apple maintains that it did in fact purchase the rights to the Chinese “iPad” trademark and that Proview refuses to uphold its end of the bargain. Proview claims that the deal was never properly made, as it argues that representatives from its Shenzhen subsidiary, which controls the mark, were not present when the agreement was signed.

Proview has set its hopes on a win against Apple to help keep it afloat. The company was at one point a prominent monitor maker, but it has struggled in recent years and is in danger of being delisted from the Hong Kong stock exchange. Various reports suggest Proview is looking for as much as $ 2 billion in damages from Apple.

A Shanghai court sided in favor of Apple last week. However, a lower court ruling from last November came down on Proview’s side.

Apple has threatened Proview with a defamation countersuit, alleging that the company’s founder has been making inaccurate statements to the press. For its part, Proview has filed a U.S. complaint against Apple accusing the company of fraud and unfair competition. The company alleges that Apple tricked Proview by using a front company to purchase the mark under “false pretext.”

Some officials in China have already begun acting on earlier rulings in favor of Proview. A small number of iPad units have been seized by local officials, though the confiscations do not appear to be widespread.

The lawsuit has high stakes for Apple, as iPad sales are growing rapidly in China. The Cupertino, Calif., company is also gearing up to unveil a third-generation iPad at a media event next week. Depending on how Apple fares in court against Proview, the next-gen iPad could potentially be blocked from sale in the country.


Potential screenshots from an iPad Retina Display look gorgeous

While we’re sure that Apple is going to show off a new iPad at the announcement next week, it’s not quite guaranteed yet that the iPad will have its own version of the Retina Display. Certainly there have been rumors to that effect, and it certainly would be cool, but we can’t be sure just yet. Nevertheless, game developer Pixels on Toast has gone ahead and done the work anyway: They have screenshots over on this blog post that show what the company’s next game, Food Run, would look like if it ran on a display with four times as many pixels as the current iPad’s screen, or a resolution of 2048 x 1536.

As you can see above (especially when compared with the images in the post of the current iPad’s screen), it looks pretty amazing. I remember when I first was buying my iPad, I had used the iPhone 4′s display for quite a while, and I went back to the iPad and was disappointed that I could still see pixelation and artifacts after getting so used to the iPhone’s screen. But if the Retina Display really did come across, the iPad’s big screen would be brighter and clearer than most computer displays, making for some really incredible interfaces.

There are drawbacks, of course. In addition to the extra power required for such a display (both in terms of processing power and battery power), developers would have to deal with higher resolution graphics, in both 2D and 3D games. Devs have already gone through this process once, however, so most developers who already put iOS games together will have some idea of how to deal with the issue. Keep in mind, however, that bigger graphics means bigger files, so Apple may have to raise the limits on various app size requirements.

At any rate, the display pictures for Food Run certainly look, well, delicious. This is all speculative, but if Apple has indeed upgraded the display on the new iPad, there could be more exciting times ahead.

[via TechCrunch]

TUAW – The Unofficial Apple Weblog

Hex Vision Classic Leather Watch Band for 6G iPod nano: Good-looking, reasonably priced

When the first watch bands started appearing for iPod nanos, I really thought the idea was ludicrous. After all, what kind of person would spend a minimum of US$ 129 on a touchscreen watch when they have a really good clock in their pocket — an iPhone — already? I felt that way until a friend of mine gave me a 6G iPod nano a few weeks ago and I coincidentally received a Hex Vision Classic Leather Watch Band (US$ 49.95) to review. Now I’m hooked on the idea of the 6G iPod nano as a watch, and this classy and inexpensive watch band has had a lot to do with my change of heart.


There’s not much to say about watch bands. Basically, they’re what hold the mechanical or electrical gadgetry onto your wrist. In the case of the watch bands that have been designed for the sixth-generation iPod nano, they hold the nano into place either using the clip on the back of the device or through some other mechanical means.

Some of the designs I’ve seen so far have been bulky affairs that encase the entire nano. More often, the watch bands use a mechanism that is like that of the Vision Classic — a stainless steel (or other material) plate that the nano clips onto. I like this more open design, as the nano doesn’t need to be removed from the band for syncing or charging.

The Vision Classic is indeed a take on the classic leather watch band. The stainless steel clip makes it easy to add or remove the nano while being unobtrusive. The leather band is comfortable and topstitched for added flair, and comes in four different colors: black, white, British tan, and grey.


The Vision Classic does what it’s designed to do: hold an iPod nano to your wrist while looking good. It feels great, it’s easy to get the nano in and out of the watch band, and — most importantly in my opinion — it’s inexpensive for a non-plastic nano band.

Yeah, you can get crappy-looking polycarbonate watch bands from a number of manufacturers (including Hex) for less money, but when it comes to nice looking bands that don’t cost an arm and a leg, the Vision Classic Leather Watch Band is a winner.

Be sure to check out the gallery of photos to see the Vision Classic and my mighty arm in action.

TUAW – The Unofficial Apple Weblog

New low level JavaScript interpreter to boost WebKit performance more than 200%

By Daniel Eran Dilger

Published: 07:29 PM EST (04:29 PM PST)
Apple’s WebKit JavaScriptCore is now a “triple tier virtual machine,” offering the potential for 2-2.5 times faster JavaScript performance in Safari.

Recent changes in Apple’s WebKit open source project (used by Safari on OS X and iOS, and to power a wide variety of other browsers) include the incorporation of the efficient new LLInt (Low Level Interpreter), which is now used by JavaScriptCore (JSC) to attempt executing code before passing it to the standard interpreters, either the bytecode virtual machine or the JIT (Just In Time complier) which builds native machine code on the fly.

“JSC will now will start by executing code in LLInt and will only tier up to the old JIT after the code is proven hot,” a change report on the new interpreter describes.

“LLInt is written in a modified form of our macro assembly. This new macro assembly is compiled by an offline assembler (see offlineasm), which implements many modern conveniences such as a Turing-complete CPS-based macro language and direct access to relevant C++ type information (basically offsets of fields and sizes of structs/classes).”

The new interpreter “is 2-2.5x faster than our old interpreter on SunSpider, V8, and Kraken [benchmarks],” the report states. “With triple-tiering turned on [to allow the LLInt to interpret code], we’re neutral on SunSpider, V8, and Kraken, but appear to get a double-digit improvement on real-world websites due to a huge reduction in the amount of JIT’ing.”

JavaScript performance in web browsers is a primary focus for optimization, as the faster and more efficiently code can be executed, the more fluid animations can run and the more sophisticated and responsive cross platform web applications can be.

The LLInt enhancements to JavaScriptCore appear to have been contributed by Filip Pizlo, who joined WebKit as a reviewer in December after acting as a “major contributor” to improvements to the JavaScriptCore JIT and Garbage Collector. Pizlo filed a bug report in January noting that “JSC should be a triple-tier VM,” and subsequently solved the issue by the end of February.

The new changes to JavaScriptCore will take some time to make it into the mainstream version of Safari, following similar WebKit enhancements of previous years. Enhancements in Apple’s next release of Safari 5.2 have been profiled in reports describing its new user interface and sharing enhancements and new privacy settings and website alert features.

Improvements to Nitro in JavaScriptCore

In 2008, WebKit announced a rewriting of JavaScriptCore as a direct-dispatch register based, high-level bytecode virtual machine originally named SquirrelFish. It compiled JavaScript into native machine code. The project was later enhanced to gain the codename SquirrelFish Extreme.

In 2009, Apple applied the enhancements to Safari 4 under the brand “Nitro,” noting that the new implementation could run JavaScript up to 4.5 times faster.

The next year, it subsequently released new SquirrelFish Extreme enhancements in Safari 5, boosting JavaScript performance on the Mac another 30 percent over the previous Safari 4.

Last year, the company added Nitro to mobile Safari in iOS 4.3, boosting JavaScript performance by 200 percent on Apple’s mobile devices. However, a minor controversy ensued after it was found that iOS only used Nitro to accelerate web apps running in Safari; this resulted in a significant speed penalty when full screen web apps were saved to the home screen.

In iOS 5, Apple solved the security issues that prevented earlier releases from running full screen web apps using Nitro, although security measures still prevent apps that use UIWebView to present a web view from invoking Nitro.

Google’s JavaScript competitors

Other WebKit browsers don’t necessarily use JavaScript Core. Google’s Chrome uses its own competing V8 JavaScript engine, for example.

V8 seeks to enhance performance by compiling JavaScript to native code before executing it. It was developed by a team led by Lars Bak, the programmer who developed Sun’s Java ME virtual machine. After Oracle acquired Sun, it filed suit against Google for infringing patents related to virtual machines, including a patent filed by Bak while working for Sun.

JavaScript, which is related to Java in name only, was originally developed at Netscape as a way to add programatic interactivity to web pages (it was previously named LiveScript). JavaScript has since become a widely established open standard, sometimes referred to as ECMAScript, after the standards body that now manages it as a specification. Microsoft formerly supported its own vbscript, but has since backed interoperability on the web through the common use of JavaScript.

Google has recently sought to replace JavaScript with its own new web programming language named Dart (originally Dash), which was codeveloped by Bak. Apple, Mozilla and Microsoft have all opposed Google’s plans to replace JavaScript with its own new language, preferring instead to continually improve upon JavaScript.

Mozilla’s Brendan Eich, who developed the original JavaScript at Netscape, recently wrote, “I guarantee you that Apple and Microsoft (and Opera and Mozilla, but the first two are enough) will never embed the Dart VM,” adding, “Google’s approach with Dart is thus pretty much all wrong and doomed to leave Dart in excellent yet non-standardized and non-interoperable implementation status,” and musing, “could Google, unlike Microsoft ten or so years ago, prevail? Only by becoming the new monopoly power on the web. We know how that story ends.”

In a discussion about Dart in December, Apple’s Oliver Hunt wrote, “Adding direct and exposed support for a non-standard language is hostile to the open-web by skipping any form “consensus” driven language development that might happen, and foisting whatever language we want on the web instead. This implicitly puts any browser that supports additional proprietary extensions in the same position as a browser supporting something like vbscript, and has the same effect: breaking the open web by making content that only works effectively in a single product.”

Google’s efforts to leverage Chrome to push its own preferred technologies rather than open standards has also occured with its own WebM video codec (as opposed to H.264) and a prioritization of Adobe’s Flash (over HTML5) for delivering video and interactivity, particularly as a differentiating feature of its Android mobile platform.


EA declares Battlefield 3: Aftershock dead

Here’s an interesting tale that might have some ramifications for the App Store in the future. After releasing a version of its popular console title Battlefield 3, subtitled Aftershock, on the App Store last month, EA abruptly pulled the game from Apple’s virtual shelves. The reviews on the game were apparently full of comments disparaging the game’s controls and tech, and EA originally said that it was pulling the title to re-evaluate how to fix it up.

Apparently they have decided on Aftershock’s final fate, and it ain’t good: An EA rep said that Aftershock won’t be returning to the App Store at all. The game’s multiplayer servers will be up for another month or so (so if you already have the game installed, you’ll be able to play it for that long), and then that’s all she wrote.

TUAW – The Unofficial Apple Weblog