Welcome!

Adobe Flex Authors: Matthew Lobas, PR.com Newswire, Shelly Palmer, Kevin Benedict

Related Topics: Adobe Flex

Adobe Flex: Article

Cover Story: How to Increase the Frame Rates of Your Flash Movies

How's Your Need For Speed?

Flash in its essence began as a tool for creating vector animations on the web. The Flash Player was designed specifically as a lightweight animation viewer to display those moving vector objects which are in their simplest form, mathematical equations that describe complex shapes made up of points, lines, curves and fills. However, nowadays developers and designers are using Flash to do a lot more than just animation, today we see Flash being used for everything from interactive banner ads to games and large applications with complex user interfaces. We are now pushing Flash to its limits and our frame rates are starting to suffer as we continue to develop content that is more application centric.

The Flash Player has had obvious performance limitations for some time now:; the vector renderer inside the player generally coughs and splutters when it attempts to play Flash Movies that contain large amounts of objects on the stage. This is because the player is not optimized to deal with large amounts of static content, by design, each frame all the vector objects on the stage have to be updated and redrawn regardless of whether they have changed, which is an intensive and unnecessary process.

In this release of the Flash Player, Macromedia have addressed these visual performance issues by making various improvements and optimizations to the renderer and adding various new features which developers can use to take advantage of these significant changes.

This article will show you how to effectively utilize these new performance related features to increase the frame rates of your Flash Movies.

Bitmap Caching
One of the most significant additions to the player in this release has to be the new Bitmap Caching capabilities. This feature gives developers that are experiencing poor frame rates the power to greatly increase the speed at which large amounts of objects are updated and drawn onto the stage by the renderer.

The renderer is a very important part of the Flash Player; it is responsible for everything that you see when you view a Flash Movie. It draws all the vector and bitmap data onto the stage. Every frame, the renderer has to update the stage and the various objects it contains to reflect any changes since the last frame using ActionScript and/or animation. This process can become quite intensive when a large amount of updating has to be done on any given frame. Using this feature gives the developer some control over the amount of work that the renderer has to perform each frame. The less work you give the renderer, the faster and smoother your Flash Movie will run.

So How Does It Work?
When you turn on Bitmap Caching for any given movie clip, the player converts the contents of the movie clip into a bitmap which it generates and then stores in memory alongside the original vector data equivalent. The renderer then displays this bitmap in place of the vector data by copying the image from memory onto the stage. This process essentially makes the renderer's life easier, because it doesn't have to update the movie clip each frame, instead it only has to draw the bitmap it generated once and from then on it simply copies the bitmap from memory onto the stage, unless of course you change the movie clip or its contents, which will regenerate the bitmap. There will be little or no visual difference when a movie clip has bitmap caching turned on. You may notice a very slight difference because the vector data is snapped to the nearest whole pixel when the bitmap is generated. Bitmap Caching also works perfectly well with nested movie clips (movie clips inside movie clips). To put it in simple terms, by turning on Bitmap Caching for a movie clip, you are essentially telling the Flash Player: "Hey Renderer, I'll make your life a little easier. Freeze this movie clip and display it as a bitmap instead because this movie clip or its contents are not going to change very often, if at all. They are static."

Turning Bitmap Caching On and Off
Bitmap Caching comes in the form of an additional movie clip property that can be switched on or off at both Authortime using the Property Inspector and at runtime using ActionScript, on a per movie clip basis.

Using the Authoring Environment
You can turn Bitmap Caching on or off for any movie clip in the authoring environment using the Property Inspector. Bitmap Caching is disabled for all movie clips by default.

To turn Bitmap Caching on select the desired movie clip instance on the stage by clicking on it. Then open the Property Inspector from the Window menu. (Window > Properties > Properties) or use the Keyboard Shortcut CTRL + F3

In the bottom right hand corner of the Properties Inspector under the Blend field, you will see an option called Use Runtime Bitmap Caching. Click this checkbox to turn Bitmap Caching on for the selected movie clip. Bitmap Caching is turned off by default for all movie clips.

Using ActionScript
Bitmap Caching can also be turned on and off at runtime using actionscript. Every movie clip object now has a new actionscript property called cacheAsBitmap. To turn Bitmap Caching ON for a movie clip with actionscript you simply need to set the value of its cacheAsBitmap property to true like so: someMovieClip.cacheAsBitmap=true; //Turn Bitmap Caching ON Similarly, to turn Bitmap Caching OFF for a movie clip using actionscript you simple need to set the value of its cacheAsBitmap property to false as follows: someMovieClip.cacheAsBitmap=false; //Turn Bitmap Caching OFF You can also determine if a movie clip has Bitmap Caching turned on, by retrieving the value of the cacheAsBitmap property: isCached=someMovieClip.cacheAsBitmap;

When Should I Use Bitmap Caching?
If used correctly, Bitmap Caching can dramatically reduce the amount of updating instructions that the renderer has to process every frame and thus your movies should in practice run a lot quicker and smoother. However in certain circumstances Bitmap Caching could have a detrimental effect on the performance of your flash movie, therefore you should choose the movie clips that you cache wisely.

Bitmap Caching works best for movie clips whose visual appearance doesn't change often or at all. That is because when a cached movie clip or its contents change, the area or region of vector data that changed is regenerated and then updated into the bitmap that is held in memory and the renderer displays the new bitmap. Bitmap Caching also works well for movie clips that contain complex vector data (i.e. shapes with lots of curves or gradient fills) as it is quicker for the renderer to copy a bitmap from memory onto the stage than draw all those vectors to the stage.

Every time you rotate, scale or change the alpha of a cached movie clip, the whole bitmap has to be regenerated. So, turning on bitmap caching for a movie clip that is constantly rotating, changing in size or contains an animation doesn't make much sense because every frame the renderer has to update the bitmap to reflect the new appearance of the movie clip aswell as redraw it to the stage, which is added overhead.

The whole idea of this feature is to reduce the amount of updates that the renderer has to perform each frame, turning it on in such situations doesn't reduce the number of updates that the renderer has to perform. On the other hand it would be very beneficial for you to turn on Bitmap Caching for all movie clips that are either static or move around, but don't change visually. It is perfectly fine to move a cached movie clip around the stage, either with ActionScript or with timeline animation because moving it around won't change its visual appearance and therefore the cached bitmap doesn't have to be updated; the renderer will merely draw the bitmap at its new position.

Valid Usecase Scenario
Consider the following scenario: You have a large application that contains multiple Window components; each Window component contains numerous other Components. Each Window component is draggable. When the user drags one of the Windows around the application, he notices a slow down and the Window has to catch up to the mouse position, which causes jerky movement.

To fix this problem, the developer turns on Bitmap Caching for each Window component instance. Now the player only has to update the internal bitmap representation of each Window component when the visual appearance of one of the UI Components inside it changes. The rest of the time, including when the Window component is being dragged around, it simply needs to move the bitmaps around the stage, as opposed to constantly updating the stage from the vector data in each movie clip. The result is a much smoother dragging experience for the user.

More Stories By Guy Watson

Guy Watson (aka FlashGuru) has been a well-recognized figure in the Flash community for around four years, supporting the community with tutorials and source files, moderating the large Flash community forums, and running his own Flash resource Web site - FlashGuru's MX 101. Guy was one of the two developers that created the award-winning zoom interface for Relevare and now works for Endemol UK, the creative force behind reality television, producing programs such as Big Brother and The Salon. Guy now spends most of his time developing Flash games and applications for high-profile clients such as Channel 5 Television, Ladbrookes, and UK Style.

Comments (24) View Comments

Share your thoughts on this story.

Add your comment
You must be signed in to add a comment. Sign-in | Register

In accordance with our Comment Policy, we encourage comments that are on topic, relevant and to-the-point. We will remove comments that include profanity, personal attacks, racial slurs, threats of violence, or other inappropriate material that violates our Terms and Conditions, and will block users who make repeated violations. We ask all readers to expect diversity of opinion and to treat one another with dignity and respect.


Most Recent Comments
Conference Call 07/07/06 04:45:58 PM EDT

Trackback Added: Conference Call; Conference Call

Drug Rehab 07/07/06 09:19:22 AM EDT

Trackback Added: Drug Rehab; Drug Rehab

Payday Loan 07/05/06 10:59:50 AM EDT

Trackback Added: Payday Loan; Payday Loan

Dental Insurance 07/05/06 10:33:31 AM EDT

Trackback Added: Dental Insurance; Dental Insurance

Data Recovery 07/04/06 08:38:25 AM EDT

Trackback Added: Data Recovery; Data Recovery

Printers 07/02/06 12:24:47 PM EDT

Trackback Added: Printers; Printers

1031 Exchange 07/01/06 02:08:26 PM EDT

Trackback Added: 1031 Exchange; 1031 Exchange

First Aid Kits 07/01/06 03:49:12 AM EDT

Trackback Added: First Aid Kits; First Aid Kits

Car Accident Lawyer 06/30/06 02:25:19 PM EDT

Trackback Added: Car Accident Lawyer; Car Accident Lawyer

Acne 06/25/06 02:22:46 PM EDT

Trackback Added: Acne; Acne

Equity Line Of Credit 06/25/06 07:38:23 AM EDT

Trackback Added: Equity Line Of Credit; Equity Line Of Credit

Forklift 06/25/06 07:22:27 AM EDT

Trackback Added: Forklift; Forklift

Term Life Insurance 06/24/06 04:21:24 AM EDT

Trackback Added: Term Life Insurance; Term Life Insurance

Eye Surgery 06/23/06 06:58:00 PM EDT

Trackback Added: Eye Surgery; Eye Surgery

Relocation 06/23/06 06:35:57 PM EDT

Trackback Added: Relocation; Relocation

Payday Loan 06/23/06 06:33:04 PM EDT

Trackback Added: Payday Loan; Payday Loan

Payday Loan 06/23/06 03:15:54 PM EDT

Trackback Added: Payday Loan; Payday Loan

Relocation 06/23/06 03:10:34 PM EDT

Trackback Added: Relocation; Relocation

Distance Education 06/23/06 01:29:59 AM EDT

Trackback Added: Distance Education; Distance Education

Relocation 06/22/06 09:36:41 PM EDT

Trackback Added: Relocation; Relocation

Vasectomy 06/22/06 12:31:50 PM EDT

Trackback Added: Vasectomy; Vasectomy

Aeon 05/27/06 03:21:41 AM EDT

This tutorial is full of syntax errors.
Functions aren't terminated properly, statements aren't properly closed with semi-colons ;.
Needs amendment.

eddyC 02/19/06 07:05:15 PM EST

Hi "noname", I was searching for a solution to this problem and found out you've had the same tysRect-problem... Have you solved it by now? :-) TIA!

noname 01/05/06 06:00:11 PM EST

hey, i just took a shot at the example in "Cover Story: How to Increase the Frame Rates of Your Flash Movies": "Scrolling Large Amounts of Text".

Unless i'm doing something incredibly wrong, it's not close to complete the way you have it in the article. Anyway, i think i've narrowed it down and just need the value for one last property: "tysRect", in the scroll() function.

what is this supposed to be set to??? is there a working fla anywhere?

thanks!

@ThingsExpo Stories
There is an ever-growing explosion of new devices that are connected to the Internet using “cloud” solutions. This rapid growth is creating a massive new demand for efficient access to data. And it’s not just about connecting to that data anymore. This new demand is bringing new issues and challenges and it is important for companies to scale for the coming growth. And with that scaling comes the need for greater security, gathering and data analysis, storage, connectivity and, of course, the...
Manufacturers are embracing the Industrial Internet the same way consumers are leveraging Fitbits – to improve overall health and wellness. Both can provide consistent measurement, visibility, and suggest performance improvements customized to help reach goals. Fitbit users can view real-time data and make adjustments to increase their activity. In his session at @ThingsExpo, Mark Bernardo Professional Services Leader, Americas, at GE Digital, will discuss how leveraging the Industrial Interne...
The increasing popularity of the Internet of Things necessitates that our physical and cognitive relationship with wearable technology will change rapidly in the near future. This advent means logging has become a thing of the past. Before, it was on us to track our own data, but now that data is automatically available. What does this mean for mHealth and the "connected" body? In her session at @ThingsExpo, Lisa Calkins, CEO and co-founder of Amadeus Consulting, will discuss the impact of wea...
SYS-CON Events announced today that Ericsson has been named “Gold Sponsor” of SYS-CON's @ThingsExpo, which will take place on June 7-9, 2016, at the Javits Center in New York, New York. Ericsson is a world leader in the rapidly changing environment of communications technology – providing equipment, software and services to enable transformation through mobility. Some 40 percent of global mobile traffic runs through networks we have supplied. More than 1 billion subscribers around the world re...
The IoTs will challenge the status quo of how IT and development organizations operate. Or will it? Certainly the fog layer of IoT requires special insights about data ontology, security and transactional integrity. But the developmental challenges are the same: People, Process and Platform. In his session at @ThingsExpo, Craig Sproule, CEO of Metavine, will demonstrate how to move beyond today's coding paradigm and share the must-have mindsets for removing complexity from the development proc...
The IETF draft standard for M2M certificates is a security solution specifically designed for the demanding needs of IoT/M2M applications. In his session at @ThingsExpo, Brian Romansky, VP of Strategic Technology at TrustPoint Innovation, will explain how M2M certificates can efficiently enable confidentiality, integrity, and authenticity on highly constrained devices.
We're entering the post-smartphone era, where wearable gadgets from watches and fitness bands to glasses and health aids will power the next technological revolution. With mass adoption of wearable devices comes a new data ecosystem that must be protected. Wearables open new pathways that facilitate the tracking, sharing and storing of consumers’ personal health, location and daily activity data. Consumers have some idea of the data these devices capture, but most don’t realize how revealing and...
trust and privacy in their ecosystem. Assurance and protection of device identity, secure data encryption and authentication are the key security challenges organizations are trying to address when integrating IoT devices. This holds true for IoT applications in a wide range of industries, for example, healthcare, consumer devices, and manufacturing. In his session at @ThingsExpo, Lancen LaChance, vice president of product management, IoT solutions at GlobalSign, will teach IoT developers how t...
A critical component of any IoT project is the back-end systems that capture data from remote IoT devices and structure it in a way to answer useful questions. Traditional data warehouse and analytical systems are mature technologies that can be used to handle large data sets, but they are not well suited to many IoT-scale products and the need for real-time insights. At Fuze, we have developed a backend platform as part of our mobility-oriented cloud service that uses Big Data-based approache...
Increasing IoT connectivity is forcing enterprises to find elegant solutions to organize and visualize all incoming data from these connected devices with re-configurable dashboard widgets to effectively allow rapid decision-making for everything from immediate actions in tactical situations to strategic analysis and reporting. In his session at 18th Cloud Expo, Shikhir Singh, Senior Developer Relations Manager at Sencha, will discuss how to create HTML5 dashboards that interact with IoT devic...
We’ve worked with dozens of early adopters across numerous industries and will debunk common misperceptions, which starts with understanding that many of the connected products we’ll use over the next 5 years are already products, they’re just not yet connected. With an IoT product, time-in-market provides much more essential feedback than ever before. Innovation comes from what you do with the data that the connected product provides in order to enhance the customer experience and optimize busi...
Artificial Intelligence has the potential to massively disrupt IoT. In his session at 18th Cloud Expo, AJ Abdallat, CEO of Beyond AI, will discuss what the five main drivers are in Artificial Intelligence that could shape the future of the Internet of Things. AJ Abdallat is CEO of Beyond AI. He has over 20 years of management experience in the fields of artificial intelligence, sensors, instruments, devices and software for telecommunications, life sciences, environmental monitoring, process...
In his session at @ThingsExpo, Chris Klein, CEO and Co-founder of Rachio, will discuss next generation communities that are using IoT to create more sustainable, intelligent communities. One example is Sterling Ranch, a 10,000 home development that – with the help of Siemens – will integrate IoT technology into the community to provide residents with energy and water savings as well as intelligent security. Everything from stop lights to sprinkler systems to building infrastructures will run ef...
Digital payments using wearable devices such as smart watches, fitness trackers, and payment wristbands are an increasing area of focus for industry participants, and consumer acceptance from early trials and deployments has encouraged some of the biggest names in technology and banking to continue their push to drive growth in this nascent market. Wearable payment systems may utilize near field communication (NFC), radio frequency identification (RFID), or quick response (QR) codes and barcodes...
Whether your IoT service is connecting cars, homes, appliances, wearable, cameras or other devices, one question hangs in the balance – how do you actually make money from this service? The ability to turn your IoT service into profit requires the ability to create a monetization strategy that is flexible, scalable and working for you in real-time. It must be a transparent, smoothly implemented strategy that all stakeholders – from customers to the board – will be able to understand and comprehe...
You deployed your app with the Bluemix PaaS and it's gaining some serious traction, so it's time to make some tweaks. Did you design your application in a way that it can scale in the cloud? Were you even thinking about the cloud when you built the app? If not, chances are your app is going to break. Check out this webcast to learn various techniques for designing applications that will scale successfully in Bluemix, for the confidence you need to take your apps to the next level and beyond.
SYS-CON Events announced today that Peak 10, Inc., a national IT infrastructure and cloud services provider, will exhibit at SYS-CON's 18th International Cloud Expo®, which will take place on June 7-9, 2016, at the Javits Center in New York City, NY. Peak 10 provides reliable, tailored data center and network services, cloud and managed services. Its solutions are designed to scale and adapt to customers’ changing business needs, enabling them to lower costs, improve performance and focus inter...
So, you bought into the current machine learning craze and went on to collect millions/billions of records from this promising new data source. Now, what do you do with them? Too often, the abundance of data quickly turns into an abundance of problems. How do you extract that "magic essence" from your data without falling into the common pitfalls? In her session at @ThingsExpo, Natalia Ponomareva, Software Engineer at Google, will provide tips on how to be successful in large scale machine lear...
You think you know what’s in your data. But do you? Most organizations are now aware of the business intelligence represented by their data. Data science stands to take this to a level you never thought of – literally. The techniques of data science, when used with the capabilities of Big Data technologies, can make connections you had not yet imagined, helping you discover new insights and ask new questions of your data. In his session at @ThingsExpo, Sarbjit Sarkaria, data science team lead ...
SYS-CON Events announced today that Fusion, a leading provider of cloud services, will exhibit at SYS-CON's 18th International Cloud Expo®, which will take place on June 7-9, 2016, at the Javits Center in New York City, NY. Fusion, a leading provider of integrated cloud solutions to small, medium and large businesses, is the industry's single source for the cloud. Fusion's advanced, proprietary cloud service platform enables the integration of leading edge solutions in the cloud, including cloud...