CIRandomGenerator Class
Definition
Important
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A CIFilter whose pixels are randomly colored.
public class CIRandomGenerator : CoreImage.CIFilter, CoreImage.ICIRandomGeneratorProtocol, IDisposabletype CIRandomGenerator = class
inherit CIFilter
interface ICIRandomGeneratorProtocol
interface INativeObject
interface IDisposable
interface ICIFilterProtocol- Inheritance
- Implements
Remarks
The CIRandomGenerator is idempotent: it always returns the same data. To retrieve a different random pattern, developers must retrieve the data from a random offset. For instance:
GKRandomSource src = MyRandomSource; // Initialized previously
var locX = (int)(src.GetNextUniform() * extent - size.Width);
var locY = (int)(src.GetNextUniform() * extent - size.Height);
CIImage img = randomGenerator.OutputImage.ImageByCroppingToRect(new CGRect(locX, locY, size.Width, size.Height));
var xlat = CGAffineTransform.MakeTranslation(-locX, -locY);
CIImage finalImg = img.ImageByApplyingTransform(xlat);
Each of the color components is independently uniformly distributed.
The following example shows this filter in use:
// Create a CIRandomGenerator filter with the input image
var random_generator = new CIRandomGenerator ();
// Get the altered image from the filter
var output = new CICrop {
Image = random_generator.OutputImage,
Rectangle = new CIVector (0, 0, 400, 300)
}.OutputImage;
// To render the results, we need to create a context, and then
// use one of the context rendering APIs, in this case, we render the
// result into a CoreGraphics image, which is merely a useful representation
//
var context = CIContext.FromOptions (null);
var cgimage = context.CreateCGImage (output, output.Extent);
// The above cgimage can be added to a screen view, for example, this
// would add it to a UIImageView on the screen:
myImageView.Image = UIImage.FromImage (cgimage);
Produces the following output:
Constructors
| Name | Description |
|---|---|
| CIRandomGenerator() |
Creates a new CIRandomGenerator with default values. |
| CIRandomGenerator(NativeHandle) |
A constructor used when creating managed representations of unmanaged objects. Called by the runtime. |
| CIRandomGenerator(NSCoder) |
A constructor that initializes the object from the data stored in the unarchiver object. |
| CIRandomGenerator(NSObjectFlag) |
Constructor to call on derived classes to skip initialization and merely allocate the object. |
Properties
| Name | Description |
|---|---|
| AccessibilityAttributedUserInputLabels | (Inherited from NSObject) |
| AccessibilityRespondsToUserInteraction | (Inherited from NSObject) |
| AccessibilityTextualContext | (Inherited from NSObject) |
| AccessibilityUserInputLabels | (Inherited from NSObject) |
| Attributes |
Configurable attributes of the filter. (Inherited from CIFilter) |
| Class | (Inherited from NSObject) |
| ClassHandle |
The Objective-C class handle for this class. (Inherited from CIFilter) |
| DebugDescription | (Inherited from NSObject) |
| Description | (Inherited from NSObject) |
| ExposedBindings | (Inherited from NSObject) |
| Handle |
Handle (pointer) to the unmanaged object representation. (Inherited from NSObject) |
| InputKeys |
Gets an array that contains the names of the input keys for the filter. (Inherited from CIFilter) |
| IsDirectBinding | (Inherited from NSObject) |
| IsProxy | (Inherited from NSObject) |
| Item[NSString] |
Gets the value that is identified by |
| Name |
Gets the filter name. (Inherited from CIFilter) |
| OutputImage | |
| OutputKeys |
Gets an array that contains the names of the output keys for the filter. (Inherited from CIFilter) |
| RetainCount | (Inherited from NSObject) |
| Self | (Inherited from NSObject) |
| Superclass | (Inherited from NSObject) |
| SuperHandle |
Handle used to represent the methods in the base class for this NSObject. (Inherited from NSObject) |
| Zone | (Inherited from NSObject) |