Click here to close now.


Adobe Flex Authors: Matthew Lobas, 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?


@ThingsExpo Stories
Mobile messaging has been a popular communication channel for more than 20 years. Finnish engineer Matti Makkonen invented the idea for SMS (Short Message Service) in 1984, making his vision a reality on December 3, 1992 by sending the first message ("Happy Christmas") from a PC to a cell phone. Since then, the technology has evolved immensely, from both a technology standpoint, and in our everyday uses for it. Originally used for person-to-person (P2P) communication, i.e., Sally sends a text message to Betty – mobile messaging now offers tremendous value to businesses for customer and empl...
As enterprises capture more and more data of all types – structured, semi-structured, and unstructured – data discovery requirements for business intelligence (BI), Big Data, and predictive analytics initiatives grow more complex. A company’s ability to become data-driven and compete on analytics depends on the speed with which it can provision their analytics applications with all relevant information. The task of finding data has traditionally resided with IT, but now organizations increasingly turn towards data source discovery tools to find the right data, in context, for business users, d...
Apps and devices shouldn't stop working when there's limited or no network connectivity. Learn how to bring data stored in a cloud database to the edge of the network (and back again) whenever an Internet connection is available. In his session at 17th Cloud Expo, Bradley Holt, Developer Advocate at IBM Cloud Data Services, will demonstrate techniques for replicating cloud databases with devices in order to build offline-first mobile or Internet of Things (IoT) apps that can provide a better, faster user experience, both offline and online. The focus of this talk will be on IBM Cloudant, Apa...
Organizations already struggle with the simple collection of data resulting from the proliferation of IoT, lacking the right infrastructure to manage it. They can't only rely on the cloud to collect and utilize this data because many applications still require dedicated infrastructure for security, redundancy, performance, etc. In his session at 17th Cloud Expo, Emil Sayegh, CEO of Codero Hosting, will discuss how in order to resolve the inherent issues, companies need to combine dedicated and cloud solutions through hybrid hosting – a sustainable solution for the data required to manage I...
The broad selection of hardware, the rapid evolution of operating systems and the time-to-market for mobile apps has been so rapid that new challenges for developers and engineers arise every day. Security, testing, hosting, and other metrics have to be considered through the process. In his session at Big Data Expo, Walter Maguire, Chief Field Technologist, HP Big Data Group, at Hewlett-Packard, will discuss the challenges faced by developers and a composite Big Data applications builder, focusing on how to help solve the problems that developers are continuously battling.
SYS-CON Events announced today that MobiDev, a software development company, will exhibit at the 17th International Cloud Expo®, which will take place November 3-5, 2015, at the Santa Clara Convention Center in Santa Clara, CA. MobiDev is a software development company with representative offices in Atlanta (US), Sheffield (UK) and Würzburg (Germany); and development centers in Ukraine. Since 2009 it has grown from a small group of passionate engineers and business managers to a full-scale mobile software company with over 150 developers, designers, quality assurance engineers, project manage...
Clearly the way forward is to move to cloud be it bare metal, VMs or containers. One aspect of the current public clouds that is slowing this cloud migration is cloud lock-in. Every cloud vendor is trying to make it very difficult to move out once a customer has chosen their cloud. In his session at 17th Cloud Expo, Naveen Nimmu, CEO of Clouber, Inc., will advocate that making the inter-cloud migration as simple as changing airlines would help the entire industry to quickly adopt the cloud without worrying about any lock-in fears. In fact by having standard APIs for IaaS would help PaaS expl...
SYS-CON Events announced today that Cloud Raxak has been named “Media & Session Sponsor” of SYS-CON's 17th Cloud Expo, which will take place on November 3–5, 2015, at the Santa Clara Convention Center in Santa Clara, CA. Raxak Protect automates security compliance across private and public clouds. Using the SaaS tool or managed service, developers can deploy cloud apps quickly, cost-effectively, and without error.
SYS-CON Events announced today that ProfitBricks, the provider of painless cloud infrastructure, will exhibit at SYS-CON's 17th International Cloud Expo®, which will take place on November 3–5, 2015, at the Santa Clara Convention Center in Santa Clara, CA. ProfitBricks is the IaaS provider that offers a painless cloud experience for all IT users, with no learning curve. ProfitBricks boasts flexible cloud servers and networking, an integrated Data Center Designer tool for visual control over the cloud and the best price/performance value available. ProfitBricks was named one of the coolest Clo...
SYS-CON Events announced today that IBM Cloud Data Services has been named “Bronze Sponsor” of SYS-CON's 17th Cloud Expo, which will take place on November 3–5, 2015, at the Santa Clara Convention Center in Santa Clara, CA. IBM Cloud Data Services offers a portfolio of integrated, best-of-breed cloud data services for developers focused on mobile computing and analytics use cases.
Learn how IoT, cloud, social networks and last but not least, humans, can be integrated into a seamless integration of cooperative organisms both cybernetic and biological. This has been enabled by recent advances in IoT device capabilities, messaging frameworks, presence and collaboration services, where devices can share information and make independent and human assisted decisions based upon social status from other entities. In his session at @ThingsExpo, Michael Heydt, founder of Seamless Thingies, will discuss and demonstrate how devices and humans can be integrated from a simple clust...
Who are you? How do you introduce yourself? Do you use a name, or do you greet a friend by the last four digits of his social security number? Assuming you don’t, why are we content to associate our identity with 10 random digits assigned by our phone company? Identity is an issue that affects everyone, but as individuals we don’t spend a lot of time thinking about it. In his session at @ThingsExpo, Ben Klang, Founder & President of Mojo Lingo, will discuss the impact of technology on identity. Should we federate, or not? How should identity be secured? Who owns the identity? How is identity ...
You have your devices and your data, but what about the rest of your Internet of Things story? Two popular classes of technologies that nicely handle the Big Data analytics for Internet of Things are Apache Hadoop and NoSQL. Hadoop is designed for parallelizing analytical work across many servers and is ideal for the massive data volumes you create with IoT devices. NoSQL databases such as Apache HBase are ideal for storing and retrieving IoT data as “time series data.”
SYS-CON Events announced today that HPM Networks will exhibit at the 17th International Cloud Expo®, which will take place on November 3–5, 2015, at the Santa Clara Convention Center in Santa Clara, CA. For 20 years, HPM Networks has been integrating technology solutions that solve complex business challenges. HPM Networks has designed solutions for both SMB and enterprise customers throughout the San Francisco Bay Area.
“The Internet of Things transforms the way organizations leverage machine data and gain insights from it,” noted Splunk’s CTO Snehal Antani, as Splunk announced accelerated momentum in Industrial Data and the IoT. The trend is driven by Splunk’s continued investment in its products and partner ecosystem as well as the creativity of customers and the flexibility to deploy Splunk IoT solutions as software, cloud services or in a hybrid environment. Customers are using Splunk® solutions to collect and correlate data from control systems, sensors, mobile devices and IT systems for a variety of Ind...
SYS-CON Events announced today that Solgeniakhela will exhibit at SYS-CON's 17th International Cloud Expo®, which will take place on November 3–5, 2015, at the Santa Clara Convention Center in Santa Clara, CA. Solgeniakhela is the global market leader in Cloud Collaboration and Cloud Infrastructure software solutions. Designed to “Bridge the Gap” between Personal and Professional Social, Mobile and Cloud user experiences, our solutions help large and medium-sized organizations dramatically improve productivity, reduce collaboration costs, and increase the overall enterprise value by bringing ...
Sensors and effectors of IoT are solving problems in new ways, but small businesses have been slow to join the quantified world. They’ll need information from IoT using applications as varied as the businesses themselves. In his session at @ThingsExpo, Roger Meike, Distinguished Engineer, Director of Technology Innovation at Intuit, will show how IoT manufacturers can use open standards, public APIs and custom apps to enable the Quantified Small Business. He will use a Raspberry Pi to connect sensors to web services, and cloud integration to connect accounting and data, providing a Bluetooth...
SYS-CON Events announced today that Micron Technology, Inc., a global leader in advanced semiconductor systems, will exhibit at the 17th International Cloud Expo®, which will take place on November 3–5, 2015, at the Santa Clara Convention Center in Santa Clara, CA. Micron’s broad portfolio of high-performance memory technologies – including DRAM, NAND and NOR Flash – is the basis for solid state drives, modules, multichip packages and other system solutions. Backed by more than 35 years of technology leadership, Micron's memory solutions enable the world's most innovative computing, consumer,...
Nowadays, a large number of sensors and devices are connected to the network. Leading-edge IoT technologies integrate various types of sensor data to create a new value for several business decision scenarios. The transparent cloud is a model of a new IoT emergence service platform. Many service providers store and access various types of sensor data in order to create and find out new business values by integrating such data.
SYS-CON Media announced that Splunk, a provider of the leading software platform for real-time Operational Intelligence, has launched an ad campaign on Big Data Journal. Splunk software and cloud services enable organizations to search, monitor, analyze and visualize machine-generated big data coming from websites, applications, servers, networks, sensors and mobile devices. The ads focus on delivering ROI - how improved uptime delivered $6M in annual ROI, improving customer operations by mining large volumes of unstructured data, and how data tracking delivers uptime when it matters most.