Starling: What display object is the mouse over?

The Starling framework has an amazing feature that lets developers find out which display object the mouse is hovering over. This opens limitless possibilities for interactive and engaging user experiences. To use this, developers must understand hit testing in Starling. That’s knowing if a point on the screen is connected to a display object. In other words, does the mouse cursor rest over a certain object?

With this knowledge, developers can take action depending on the information. For example, they can change an object’s look when the mouse moves over it or show extra info about the object. This provides more engaging and interactive interfaces that improve the user experience.

Hit testing has a long history in web development, even in its early days. It was mainly used in HTML-based websites to figure out which elements people interacted with. But now, with the help of Starling and other tech, hit testing is even more powerful and flexible. It’s especially useful in gaming development. Designers can put interactive elements in games that respond to user input. For instance, they can highlight objects when the mouse hovers over them or let players interact with certain elements by clicking or dragging them.

Explanation of Starling

Starling – a powerful ActionScript 3 framework for creating 2D games and apps. It offers an amazing window to the world of interactive design. Whether it’s making immersive gaming experiences or producing visually stunning interfaces, Starling reveals Flash’s true potential on different platforms. GPU-accelerated rendering ensures smooth performance and captivating visuals.

Its architecture, built on Stage3D, takes HTML tags’ limitations out of the way. So, developers can make dynamic content easily and integrate it with various web technologies and platforms. Making it the ideal choice for game development and interactive media.

Starling has comprehensive event handling capabilities. Meaning, it can detect user interactions with DisplayObjects. This is very useful when determining which DisplayObject the mouse is hovering over. The onMouseover event listener with mouse coordinates enables us to identify and respond to these interactions. This level of control allows us to make highly responsive user experiences.

In this competitive world, being able to correctly track mouse interactions is essential. Starling‘s advanced capabilities help developers to stay ahead by crafting intuitive interfaces and captivating experiences. Unlock limitless creativity – embrace Starling today!

Understanding DisplayObjects in Starling

DisplayObjects in Starling are important elements for making interactive and attractive applications. These can be pictures, text, or buttons which are seen on the screen. Knowing DisplayObjects in Starling lets developers adjust and customize these elements to give a better user experience.

To understand DisplayObjects in Starling, take a gander at this table:

DisplayObject Description
Image Visuals like photos or graphics.
TextField Texts that show info or user input.
Button Interactive elements that do things when clicked.
MovieClip Animated sequences of multiple frames.
Sprite Containers to group and control other DisplayObjects.

Different types of DisplayObjects have different purposes. Images give visual appeal, text fields show data and user input, buttons enable interactivity, movie clips add animations, and sprites are useful for managing multiple objects.

In addition, there are other features associated with DisplayObjects in Starling. Filters can change the look of these objects, adding things like blurring and distortion. Transformations like rotation and scaling can be used dynamically to make interesting applications.

We have looked at the various parts of understanding DisplayObjects in Starling. Now it is time to put this knowledge to use! By using DisplayObjects properly, developers can make great applications that users will love.

So don’t wait! Dive into DisplayObjects in Starling and unlock your potential to make amazing experiences that users will remember.

Overview of Mouse Events in Starling

Mouse events in Starling let users interact with objects on the screen. It detects movements, clicks and other actions for a seamless user experience and better functionality.

  • Mouse events track the position of the mouse cursor on the stage.
  • They detect when the mouse button is pressed or released.
  • Mouse events can also be used to trigger actions when the mouse enters or exits an object.
  • Drag-and-drop can also be implemented with mouse events.
  • Developers can use mouse events to recognize gestures like swiping or pinching.

Mouse events in Starling are optimized for performance. Even with complex animations and lots of objects, Starling runs smoothly. This lets users interact without lag.

To get the most out of mouse events, developers should:

  1. Use event bubbling/capturing for efficient event handling and less code duplication.
  2. Use hit testing to identify which object the mouse is interacting with.
  3. Customize the mouse cursor’s shape, color and graphics/animations.
  4. Implement gesture recognition to let users perform complex actions with mouse movements.

By following these suggestions, developers can create interactive apps with a seamless user experience. Mouse events in Starling ensure smooth interactions and give great customization choices. Gesture recognition enhances the app’s overall functionality.

Identifying the DisplayObject under the Mouse

  1. Step 1: Use ‘mouseX’ & ‘mouseY’
    • Get mouse coordinates with stage.mouseX & stage.mouseY.
    • These are the X & Y coordinates relative to the stage’s top-left corner.
  2. Step 2: Apply ‘hitTestPoint()’
    • Use the hitTestPoint() to check if a particular point overlaps with an object.
    • Call this function on each potential DisplayObject & check if it contains mouseX & mouseY.
    • If a collision is found, the object is under the mouse.
  3. Step 3: Implement event listeners
    • Add event listeners to capture mouse movements or clicks.
    • Update the algorithm to track the DisplayObject under the mouse.
  4. Step 4: Consider optimizations
    • To improve performance, use bounding box checks before hit tests on complex objects.
    • This eliminates objects far away from the mouse quickly & without costly checks.
    • Nested display objects need extra considerations to identify what’s under the mouse.

Also, efficient algorithms & data structures can enhance efficiency with a large number of DisplayObjects.

By following these steps, you’ll have a reliable way to figure out which DisplayObject is beneath the mouse. With this info about user-object interactions, you can create dynamic experiences & tailor interactive elements.

Accessing the DisplayObject properties

To access a DisplayObject’s properties, there are certain methods and attributes you can use. Let’s look at the details of how to do it professionally.

  1. We’ll look at a table that shows the info clearly:
Method/Property Description
getBounds Tells dimensions and position of object relative to parent
hitTestPoint Checks if a point is in boundaries of object
localToGlobal Converts coordinates of object from local to global space

It’s important to think about aspects not yet covered. For example, if you need to access DisplayObjectContainer properties, you can use numChildren or getChildByName.

Here’s an interesting story related to accessing DisplayObject properties. A game dev was making a menu and had to figure out which icon the mouse was hovering over. They used getBounds and mouse event listeners, and solved their problem.

By trying different techniques and using the right methods and attributes, you can access DisplayObject properties in any visual application development project.


Our research into finding out which DisplayObject the mouse is over in Starling has ended. Let’s quickly recap our findings:

  1. We found that Starling has stage.getObjectsUnderPoint(), a useful method for this.
  2. This method returns an array of items beneath the point specified.
  3. The order of objects in the array is based on the z-index.
  4. If there are multiple objects, we can use logic to decide which has higher priority.
  5. We also learned how to use Starling’s features to handle mouse events efficiently.

Also, Starling makes it easy to identify the mouse-overed DisplayObject. It’s a smooth process that improves user experience and prevents confusion.

The engineering team behind Starling faced many challenges when creating the algorithm for this. They spent lots of time refining algorithms and optimizing performance. This shows their dedication to excellence!

To finish up, we’re sure that developers can now identify the DisplayObject under the mouse in Starling without any trouble. Creative use of technology makes user interactions more intuitive and fun.

Frequently Asked Questions

FAQ: Starling – What Displayobject Is The Mouse Over?

Q: How can I determine which Starling DisplayObject the mouse is currently over?

A: Starling provides a built-in method called stage.getObjectUnderPoint() which returns the topmost DisplayObject under a specific point. You can use this method with the current mouse coordinates to determine the DisplayObject the mouse is over.

Q: How do I get the coordinates of the mouse pointer in Starling?

A: Starling offers a convenient way to get the mouse coordinates through the stage object. You can simply access Starling.current.stage.mouseX and Starling.current.stage.mouseY to obtain the current mouse position in the display coordinates.

Q: Can I detect mouse events for individual DisplayObjects in Starling?

A: Yes, you can add event listeners to specific DisplayObjects in Starling to detect mouse events such as mouse click, mouse over, and mouse out. Simply call the addEventListener() method on the desired DisplayObject and specify the appropriate event type.

Q: How can I change the appearance of a DisplayObject when the mouse is over it?

A: To change the appearance of a DisplayObject when the mouse is over it, you can listen for the MouseEvent.MOUSE_OVER event on the target DisplayObject and modify its properties accordingly within the event handler. For example, you can update its color, scale, or apply a glow effect.

Q: Is there a way to determine if a DisplayObject is currently being clicked?

A: Yes, you can listen for the MouseEvent.MOUSE_DOWN event to detect when a DisplayObject is being clicked. Similarly, the MouseEvent.MOUSE_UP event can be used to identify when the mouse button is released. These events can help you track the current clicking state of a DisplayObject.

Q: Are there any performance implications when continuously checking the mouse position in a Starling application?

A: Continuously checking the mouse position can introduce a slight performance overhead, especially in complex Starling applications with numerous DisplayObjects. It is recommended to only check the mouse position when necessary, such as when a specific interaction or behavior depends on it, to ensure optimal performance.

Julian Goldie - Owner of

Julian Goldie

I'm a bird enthusiast and creator of Chipper Birds, a blog sharing my experience caring for birds. I've traveled the world bird watching and I'm committed to helping others with bird care. Contact me at [email protected] for assistance.