IOS Animation and Tuning for Efficiency

At present, iOS apps are more profitable than Android and Windows Phone apps. But the developers still need to frequently look for innovative ways to make the user interface (UI) of the iOS app fast, responsive and appealing. The high quality graphics and fluid animations help developers to make the iOS applications more interactive and attractive. But the bundle size of the application is increased each time animation is embedded into it. Also, the animations adversely affect the loading speed and performance of the iOS application significantly. Hence, it becomes essential for iOS app developers to understand the common ways to optimize iOS animations.

7 Simple Ways to optimize iOS Animations

1) Render Graphics through GPU

An iOS application developer has option to render graphics through both GPU and CPU. But as a specialized chip, GPU is designed with features to optimize graphic creation. Hence, the developer can easily optimize the animations by rendering most graphics through GPU instead of CPU. However, he must not forget that graphics related performance of the app will be impacted drastically each time the processing power of GPU runs out, despite the CPU having adequate processing power.

2) Identify the GPU Bottlenecks

The developers must maintain a balance between CPU and GPU while rendering graphics. He also needs to identify the bottlenecks that make the processing power of the GPU run out. Often pixel mismanagement, blending and excessive composition put additional burden on the GPU, and affects its processing power drastically. The developer must keep in mind these GPU bottlenecks to boost the performance of iOS animations.

3) Use a Single View

Often developers create animations with multiple views. But each additional view increased the burden on the Core Animation through core compositing. The developer can easily optimize iOS animations using a single view without any sub-views. He must take advantage of various prebuilt methods to draw the animations directly and with a single view.

4) Assess Alignment of Pixels

The developers often define images and frames in terms of pixels to make the app more responsive. But they must define and align the pixels with 100% accuracy to boost the performance of iOS animations. The Core Animation allows developers to use align pixels with any value. The developers still have to use anti-aliasing to rectify the wrong values. Hence, it is always important for developers to check the alignment of pixels regularly and ensure that there is no error.

5) Decompress Images in Advance

The amount of time required for decompressing different formats and sizes of images differ. For instance, JPEGs require addition time for decompression than PNGs. But the decompression process must be optimized to boost the performance of the animations. The developers can always consider decompressing the images at the time of before the drawing process.

6) Specify Shadow Shape Explicitly

The iOS app deliver can allow Core Animation to determine the shape of shadow. But the performance of the app will be affected adversely when the shape of the shadow is determined by Core Animations. Hence, the developers must specify the shadow shape explicitly by using the shadowPath property of CALayer. Based on the path object property specified by the developer, Core Animation will draw and cache the shadows, without boosting the performance of the iOS app.

7) Review Core Animation Layers

Core Animation delivers animations on iOS devices through layers. As a simple abstraction, each Core Animation layer is designed with features to interact with GPU. But the components in view’s drawRect: are processed by the CPU, and subsequently transferred to GPU as texture. Hence, the performance of the iOS apps can be impacted by the additional time required by both GPU and CPU. The developers must keep the Core Animation layers separate, and assess them individually to find out the defects that increases processing time of GPU and CPU operations.

It is also important for the developers to assess the performance of animations included in an iOS app. They must use different versions of iPhone and iPad to evaluate how the animation works on various iOS devices. However, they need to use real iOS devices instead of emulators to assess the performance of an animation more effectively. Based on the performance evaluation, they can easily identify the animations that require performance tuning.