Using this very simple class, you can quickly get an idea of what your color-blind users will experience when they use your App. This is achieved by converting the colors and acuity of your App in real-time.

Demonstration

You can download the demo App contained within this repository or watch the following video.

Integration

ALDColorBlindEffect simulates how a given UIView will be experienced by users with the most common types color-blindness and varying degrees of visual acuity. To get started, you simply need to set the view property of the [ALDColorBlindEffect sharedInstance].

If you would like to simulate color-blindness across your whole App, you just need to add one line of code to your application:didFinishLaunchingWithOptions method, like this:

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
    [ALDColorBlindEffect sharedInstance].view = self.window;

    return YES;
}

Creating an Effect

Color

To see how your App looks to your colourblind users, you can set the type property to§ any one of the following effects:

ALDColorBlindEffectTypeNone
ALDColorBlindEffectTypeProtanopia
ALDColorBlindEffectTypeDeuteranopia
ALDColorBlindEffectTypeTritanopia
ALDColorBlindEffectTypeRodMonochromacy
ALDColorBlindEffectTypeConeMonochromacyLRed
ALDColorBlindEffectTypeConeMonochromacyMGreen
ALDColorBlindEffectTypeConeMonochromacySBlue
ALDColorBlindEffectTypeDog

For example, to simulate Deuteranopia, you would need to add the following line of code:

[ALDColorBlindEffect sharedInstance].type = ALDColorBlindEffectTypeDeuteranopia;

Adding Blur

As well as altering the colors of your App, you may also like to simulate the experience of those users with varying degrees of visual acuity. This can range from minor blurred vision to total loss of sight. To simulate this, give the blurAmount property any value between 0 (i.e. no blurriness) and 1 (complete blurriness). For example, for a small amount of blur, you would need to add the following line of code:

[ALDColorBlindEffect sharedInstance].blurAmount = 0.03;

Advanced Features

Quality

Should you find that performance is suffering whilst you are simulating color-blindness, you can reduce the quality of the effect by setting the quality property to any of the following:

ALDColorBlindEffectQualityLow,
ALDColorBlindEffectQualityMedium,
ALDColorBlindEffectQualityHigh

The default is ALDColorBlindEffectQualityMedium.

Case Study: Tube Tracker

This video demonstrates how you could integrate this class into your project using the Settings.bundle.

Notice how a tester will be forced to use other means (e.g. VoiceOver) to navigate around the App when the blur is sufficiently high.

## CocoaPods

You can also add this project to yours by using CocoaPods. To do this, add the following line to your Podfile:

pod 'ALDColorBlindEffect`, '~>1.0.0'