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OpenGL based transition for iOS. Based on GPUImage.

Overview

The YUGLTransition is a library that lets you create GPU-based transition to UIView and UIViewController.

It uses GPUImage for the rendering part.

There're some ready-to-use transition effects, like ripple, swap, doorway, flash, flyeye, etc. And it allows you to create your own custom transitions by providing your custom transition filter.

Transitions

Preset

There're six preset transition filters currently. YUGLCrossDissolveTransitionFilter YUGLFlashTransitionFilter YUGLFlyeyeTransitionFilter YUGLRippleTransitionFilter YUGLSwapTransitionFilter YUGLDoorwayTransitionFilter

Most of the preset filters are ported from glsl-transtion (A javascript library that uses WebGL Shaders to perform transition). You can see demos of the transitions here.

Custom

You can create your own transition filter by subclassing GPUImageFilter, providing your transition shaders and confirming to the YUGLTransitionFilter protocol which only have one property: progress. All the preset filters are great examples.

Pull requests for new transition filters are welcome.

Performance

Performance varies with devices and the filter you choose (the custom shader you write).

For instance, iPhone 4 is capable of performing a full-screen transition with flash transition filter, but it's hard for it to perform the transition with swap filter.

In general, iPhone 4s is capable of playing with all the transition filters currently in this project.

Note: The performance of a transition on a real device usually improves, compared to that on the simulator.

Usage

YUGLViewTransition

Use YUGLViewTransition to create view transition.

[YUGLViewTransition transitionWithView:self.imageView
                              duration:1.0
                      transitionFilter:[[YUGLFlashTransitionFilter alloc] init]
                        timingFunction:nil
                              reversed:NO
                            animations:^{
                                self.imageView.image = nextImage;
                            } completion:^(BOOL finished) {
                                NSLog(@"transition completed.");
                            }];

view : The UIView object where the transition take place.

duration : Transition duration.

transitionFilter : A GPUImageOutput<GPUImageInput,YUGLTransitionFilter> (basically a GPUImageFilter) object which is used for rendering the transition.

timingFunction : A YUMediaTimingFunction object that controls the transition animation curve. Just like CAMediaTimingFunction.

reversed : Indicates whether the reverse version of the transition should be used.

animations : A block object containing the changes to commit to the view.

completion : A block object to be executed when the transition ends.

YUGLViewControllerTransition

Use YUGLViewControllerTransition to create transitions between view controllers.

YUGLViewControllerTransition is just a class that confirms the UIViewControllerAnimatedTransitioning protocol. You can use this class in the view controller transition process. See more about UIViewControllerAnimatedTransitioning from Apple.

Requirements

• Automatic Reference Counting (ARC)
• iOS 7.0+
• Xcode 5.0+
• Demo project requires cocoapods: pod install

Contributing

If you find a bug and know exactly how to fix it, please open a pull request. If you can't make the change yourself, please open an issue after making sure that one isn't already logged.