iPhone-6-plus_iPhone6_iPhone-5sIn conjunction with iOS 8 Apple unveiled the new iPhone 6 including the Plus version which show, respectively, with a screen of 4.7 “and 5.5” inches. The new iPhone fundamentally change the screen resolution and retina display than previous models. With full compatibility with standard sRGB we have a better contrast, brightness and white balance improved.
Retina display HD resolution:

  • iPhone 6 1334×750 pixels with 326 ppi
  • iPhone 6 Plus 1920×1080 pixels with 401 ppi

Points

 Initially, the coordinates of all the images were specified in points, these are abstract units and only make sense in this particular coordinate space.
In the original iPhone, the points correspond perfectly to the actual pixels on the screen, but now this is no longer true.
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Rendered Pixels
The drawings Pointbaseed are rendered in pixels. This process is known as “rasterization”.
The point coordinates are multiplied by scaling factors to obtain the coordinates of the pixels. Scale factors produce more for a higher level of detail. Scale factors are typical for iOS × 1, 2 × and 3 ×.

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The content is made to the pixels with the scale factor. This process is called rasterization.

The content is defined mathematically by using the coordinates of the point.

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Physical Pixels
The new iPhone 6 Plus has a screen with pixels of lower resolution than the raster image that is shown in the previous step. Before the image is displayed on the screen, you need to downsampling (resized) per pixel of lower resolution.

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The last step is to show the pixels calculated on the physical screen. Each screen is characterized by a density of pixels per inch (PPI). This number indicates the number of pixels covered by a thumb, and then how big the pixels appear in reality.
Line rendering

To demonstrate different pixel rendering on different devices, we compare as a broad line 1 point is given on the different iPhone models:

Original iPhone without the Retina Display. Scale factor is 1 (1x).
iPhone 5 with Retina Display, the scale factor is 2 (2x).
iPhone 6 Plus – with Retina Display HD. Scale factor is 3 (3x), and the image is then scaled by the rendered 2208 × 1242 pixels to 1920 × 1080 pixels.

The reduction ratio is 1920/2208 = 1080/1242 = 20 / 23. This means that every 23 pixels from the original render must be mapped to 20 physical pixels. In other words, the image is reduced by approximately 87% of its original size.

 

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iOS iPHONE‘S RESOLUTIONS GUIDE

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