Retina MBP: Why do apps need update to take advantage of Retina?

[baryon]

The new Retina MBP poses a lot of questions. It's a great thing that you can have so many pixels on a relatively small screen, as it allows huge amounts of detail. However, screen elements that are bound to be a certain number of pixels in size will appear smaller than they were intended (a 100 x 100 pixel image will be the same number of pixels, but 4 times less the physical area than on the previous MBP).

So I do understand that the high pixel density causes some problems for apps that aren't designed for it. But what if I'm okay with that? What if I don't mind reading small text, and clicking on small buttons? In that case, in theory, wouldn't it be possible for every app to potentially make use of every pixel on the screen, without having to resort to pixel-doubling?

Apps would already work on a huge external monitor that may have the same number of pixels as the Retina MBP, so is this limitation purely arbitrary by Apple? Basically, is there going to be a flag in the app that says "Yes I'm ready for the Retina resolution, I will increase every interface element to compensate for the small pixels", otherwise OS X will deliberately make the app think that it's running on a standard-resolution screen?

I'd love some clarification! Thanks.

 

[Stetrain]

The 15" Retina Macbook Pro by default displays things at the same physical size as a 1440x900 display (same as old 15" Macbook Pro).

You can choose between a couple of options to increase or decrease the scale of everything.

It doesn't display some apps large and some apps small. It takes apps that do not have the larger Retina graphics and scales them up to be the same physical size as everything else.

If they displayed non-retina apps at native size on a 2880x1800 display it would be a pretty bad experience.

If you want more real estate so you can fit more things on screen, there is an option in the display preferences that lets you change the scaling. One of the options makes apps and text as physically small as it would be on a confidential 1920x1200 display, providing the same amount of real estate as the old 17" Macbook Pro.

 

[7even]

I think the issue with non-retina-enabled apps is that the OS reports the screen as 1440x900. The area taken up is the same, but each pixel being drawn by the app corresponds to 4 being displayed. Some things may not be as sharp, I suspect, e.g. Chrome, as they would be in a Retina-aware app.