By scott
I haven’t blogged in a while, mainly because I have been extremely busy at work. One of the projects we launched tonight is the WALL-E takeover of the Disney.com homepage.
Earlier this year I was lucky enough to go up to the Pixar offices (yes it is an amazing office) to discuss this project. June 24 seemed so far away when we were storyboarding out the concept and presenting our ideas. I must admit, the final rendered version looks much better then those sketches and block animations we toyed around with.
From a technical standpoint there isn’t much to write home about here, however, it was a pretty cool project to say I worked on…sorta. Check it out, it will only be up for a few days.
By scott
I have been meaning to add this to my blog for quite some time now. I have read a few postings related to this topic but I am surprised there aren’t a lot more people complaining about this. Personally I feel Adobe really dropped the ball with this bug. I guess I should explain what the bug is before I go on.
Lets pretend we’re creating a button, now I know most of my readers are developers and for the most part we would never create a simple button like this using multiple frames on the timeline. But we all know that designers love to use the timeline and create button states using frames and frame labels. I actually think this posting will help designers as much as it will help the developers who are working with said designers.
Now lets pretend our button has 3 states, up, over, and down and each state is represented on the timeline, 5 frames apart and the frame is labeled the same as each state. So the first frames label is “up”, the 5th frames label is “over”, and the 10th frames label is “down”. On each frame there is a MovieClip named button and each key frame has the same graphic just tinted differently to differentiate the states. Then on our code layer we set up MouseEvents for each state MOUSE_OVER, MOUSE_OUT, and MOUSE_DOWN, in each of the event handlers we move the playhead to each frame using the gotoAndStop method while passing in the frame label that we want the playhead to move to. Ok, so this is all straight forward. Very flash 4. The interesting part of this is when you try to access sibling displayObjects on the same frame right after we call gotoAndStop.
To illustrate this bug lets add a layer below the layer that has our button on it. On this layer add a keyframe at frame 5 and add a MovieClip, whatever you want, import a picture draw a shape, it doesn’t matter. Just as long as you give it an instance name of overClip. Right after we call gotoAndStop(’over’) try and trace (overClip). If you are not completely following me right now here is a picture of what my timeline looks like:
And our code will look something like this (excuse the timeline code, but it is the easiest way to demonstrate this bug).
button.addEventListener(MouseEvent.MOUSE_OVER, rollover);
button.addEventListener(MouseEvent.MOUSE_OUT, rollout);
function rollover(e:MouseEvent):void {
gotoAndStop('over');
trace('the instance name of the overclip is: ' + this.overClip.name);
}
function rollout(e:MouseEvent):void {
gotoAndStop('up');
}
In the rollover function you will notice I added a trace that traces out the name property of the overClip that appears on the out frame (or frame 5 for those of you who like numbers). If you were to run this code you will notice that the rollover works, the playhead moves to frame 5 and visually you see the change, however, the trace statement throws the following error “TypeError: Error #1009: Cannot access a property or method of a null object reference.” Null?? How can that be, the playhead is at frame 5, and the overClip is on frame 5, why is overClip null? Good question! The other odd thing is if you trace out numChildren right after the gotoAndStop(’over’) call it will return the correct number of child displayObjects. How can the player know how many children there is but still throw an error saying we’re trying to access a null object reference?
This was a very common practice in AS2, especially in highly creative sites with both Flash Designers and Flash Developers. And as more creative shops start embracing Flash 9 I think this issue will become more common.
Well, the first thing I thought to do was to call stage.invalidate() before I called gotoAndStop(’over’), in theory this should force a redraw and fire the render event. Well it did fire the render event but I still couldn’t trace out the clip on frame 5. Arghhh!
The one thing I did notice is the error is only thrown the first time rollover is called. Everytime after that the reference to overClip traces out fine. So this got me thinking. It looks like displayObjects do not register until the current frame cycle is complete. For those who do not know, a frame cycle is two parts, first the code executes, once the code on that particular frame executes any display updates are executed (adding overClip to the timeline is a display update).
The first approach to get around this bug I thought up was to kick off a EnterFrame event in the rollever function, after the EnterFrame event is fired, it still didn’t trace out overClip. Then I thought maybe I need a second frame cycle to register everything because technically the EnterFrame event fires at the exact moment the playhead hits the frame which is exactly the same problem we already have. Ok, so lets allow for two EnterFrame events to fire, kill the event, and trace out overClip. Guess what, that works. Here is the code for this approach.
var count = 0;
button.addEventListener(MouseEvent.MOUSE_OVER, rollover);
button.addEventListener(MouseEvent.MOUSE_OUT, rollout);
function rollover(e:MouseEvent):void {
count = 0;
gotoAndStop('over');
addEventListener(Event.ENTER_FRAME, rolloverDelay);
}
function rolloverDelay(e:Event):void {
count++
if (count == 2) {
removeEventListener(Event.ENTER_FRAME, rolloverDelay);
trace('the instance name of the overclip is: ' + this.overClip.name);
}
}
function rollout(e:MouseEvent):void {
gotoAndStop('up');
}
Yes this works, but imagine how complex this mess of code would get if we had a complex 12 state button with animations on each state. Not very practical.
The only way I could come up with to get around this issue was to create an EnterFrame that fires right off the bat, moves the playhead to the last frame of the timeline, and then returns it to the first frame. This ensures that everything that exists on the last frame will be registered and you will be able to access it immediately following the gotoAndStop(’over’) call. The key to this approach is only items that are still in the display list on the last frame will register. If you have a blank keyframe after overClip it will not register if the last frame of the timeline is beyond that. Here is the code for this approach.
button.buttonMode = true;
button.addEventListener(MouseEvent.MOUSE_OVER, rollover);
this.addEventListener(Event.ENTER_FRAME, frameentered);
this.addEventListener(Event.RENDER, rendered);
function frameentered(e:Event) {
this.removeEventListener(Event.ENTER_FRAME, frameentered);
if (overClip == null) {
stage.invalidate();
this.gotoAndStop(totalFrames);
}
}
function rendered(e:Event):void {
if (this.currentFrame == this.totalFrames) {
this.gotoAndStop(1);
}
}
function rollover(e:MouseEvent):void {
trace('the instance name of the overclip is: ' + this.overClip.
}
Excellent, we’re making progress. But we are working with a very simple example, a two state button (up and over). What if we had a more complex button, say 4 states (up, over, down, and disabled), and at each state different assets were added to the timeline like so.
I know, I said complex, and this timeline is far from complex, where are all the tweens, and hundreds of layers, guides, and masks. Well, lets just pretend all that fun stuff is there for now.
If we were to try the last approach with this more complex timeline we still wouldn’t have access to the clips on the over and down frames. This is because we moved the playhead from the first frame to the last frame and back to the first frame again. The playhead never touched anything in between so the clips on the over and down frames would not have been registered yet.
The first approach I came up with to register the clips on all the frames was quite innovative, so I thought. Basically I used the currentLabels array property of MovieClip. For those who don’t know, the MovieClip class now contains a currentLabel and a currentLabels property. The currentLabel returns a FrameLabel object if one exists for the current frame that the playhead is currently on. A FrameLabel Object contains two properties, name, and frame. The name property is the frame label name and the frame property is the frame number (int) of the current frame the playhead is on. The currentLabels property of MovieClip returns an array of FrameLabel Objects containing all the FrameLabels for the targeted MovieClip. Using the currentLabels array I thought I could loop through each FrameLabel in the array and move the playhead to each frame label and once it is complete return the playhead back to the first frame. However, you cannot use a traditional for loop because the frame cycle will not occur until the for loop is complete. Instead I set up a counter variable and use an EnterFrame to move through each FrameLabel Object for targeted MovieClip. This approach is very similar to our previous approach with more stops in between. Lets call this approach the milk run. Here is what my code looked like for this approach.
button.buttonMode = true;
var count:int;
if (count == 0) {
this.visible = false;
addEventListener(Event.ENTER_FRAME, proxyframes);
addEventListener(Event.RENDER, rendered);
}
function proxyframes(e:Event) {
stage.invalidate();
gotoAndStop(this.currentLabels[count].name);
trace(this.currentFrame);
}
function rendered(e:Event):void {
count++
trace('render called' + this.currentFrame)
if (count == this.currentLabels.length) {
init();
gotoAndStop(1);
removeEventListener(Event.ENTER_FRAME, proxyframes);
removeEventListener(Event.RENDER, rendered);
}
}
function init() {
this.visible = true;
button.addEventListener(MouseEvent.MOUSE_OVER, rollover);
button.addEventListener(MouseEvent.MOUSE_OUT, rollout);
button.addEventListener(MouseEvent.MOUSE_DOWN, press);
button.addEventListener(MouseEvent.MOUSE_UP, release);
}
function rollover(e:MouseEvent):void {
gotoAndStop('over');
trace(overClip.name);
}
function rollout(e:MouseEvent):void {
gotoAndStop('up');
}
function press(e:MouseEvent):void {
gotoAndStop('down');
trace(downClip.name);
}
function release(e:MouseEvent):void {
gotoAndStop('disabled');
trace(disabledClip.name);
//disable buttons if there was a parent clip parent.mouseChildren = false would also work.
button.buttonMode = false;
button.removeEventListener(MouseEvent.MOUSE_OVER, rollover);
button.removeEventListener(MouseEvent.MOUSE_OUT, rollout);
button.removeEventListener(MouseEvent.MOUSE_DOWN, press);
button.removeEventListener(MouseEvent.MOUSE_UP, release);
}
So why doesn’t this work. Well if you remember what I said earlier, moving the playhead only registers the last frame that it was on. If you run this code you will notice the rollover and rollout methods return null but the release method traces out the correct value, this is because that was the last stop on our playhead milk run.
In order for this approach to work I would have to layout my timeline appropriately. Each state clip should be on its own layer with nothing after it (including blank keyframes) on the timeline, like so:
Now you will notice that the above code works, we are now able to trace out the extra clips that appear on each frame with a label. However, now that everything exists on the last frame we really don’t need to loop through each FrameLabel to register the clips, we can just use our first trick and move the playhead to the last frame, once it renders move back to the first frame. Even though the looping through the FrameLabels code is overkill for this example I thought I would keep it in so people know that capability exists.
So we are able to access sibling displayObjects now but there still is one functional issue. Since the frames are cascading on the timeline when the playhead is on the down frame both downClip and overClip are visible. Likewise, when the playhead is on the disabled FrameLabel upClip, downClip, and disabledClip are visible. That little bug is not going to slip by the creative department. Normally we would get around this issue by adding blank keyframes on the frame following where the extra clip was displayed. If we were to do this in our example the clips wouldn’t register because they do not exist on the last frame and we would be right back where we started. There are two ways around this, one involves more code (the developer approach), the other involves more keyframes (the designer approach). Both are valid.
The timeline approach basically consists of adding keyframes (not blank keyframes) on the frame after the frame where the extra clip appears and setting the alpha of the clip on the second frame to 0. This ensures that the clip is still on the display list in the last frame and allows it to register. With this approach your timeline would now look like so:
Depending on what else is happening in your application this approach may not work. This is when you have to resort to code (yay). Basically with code we do the same thing, however, instead of simply setting the alpha to 0 we’ll set the visibility to false. This only requires three extra lines of code which are included below.
stop();
button.buttonMode = true;
var count:int;
if (count == 0) {
this.visible = false;
addEventListener(Event.ENTER_FRAME, proxyframes);
addEventListener(Event.RENDER, rendered);
}
function proxyframes(e:Event) {
stage.invalidate();
gotoAndStop(this.currentLabels[count].name);
//gotoAndStop(this.totalFrames);
trace(this.currentFrame);
}
function rendered(e:Event):void {
count++
trace('render called' + this.currentFrame)
if (count == this.currentLabels.length) {
init();
gotoAndStop(1);
removeEventListener(Event.ENTER_FRAME, proxyframes);
removeEventListener(Event.RENDER, rendered);
}
}
function init() {
this.visible = true;
button.addEventListener(MouseEvent.MOUSE_OVER, rollover);
button.addEventListener(MouseEvent.MOUSE_OUT, rollout);
button.addEventListener(MouseEvent.MOUSE_DOWN, press);
button.addEventListener(MouseEvent.MOUSE_UP, release);
}
function rollover(e:MouseEvent):void {
gotoAndStop('over');
trace(overClip.name);
}
function rollout(e:MouseEvent):void {
gotoAndStop('up');
}
function press(e:MouseEvent):void {
overClip.visible = false;
gotoAndStop('down');
trace(downClip.name);
}
function release(e:MouseEvent):void {
gotoAndStop('disabled');
trace(disabledClip.name);
overClip.visible = false;
downClip.visible = false;
button.buttonMode = false;
button.removeEventListener(MouseEvent.MOUSE_OVER, rollover);
button.removeEventListener(MouseEvent.MOUSE_OUT, rollout);
button.removeEventListener(MouseEvent.MOUSE_DOWN, press);
button.removeEventListener(MouseEvent.MOUSE_UP, release);
}
That’s it. Adobe, if you are reading this, please, please, please fix this bug. It is very annoying. It is obvious that Flash Player 9 was built with Flex in mind (aka no timeline) since that is all that was available when Flash Player 9 was released. I remember reading someone from Adobe admitting that on their personal blog, if I can find the link again I will post it in the comments below. I covered a lot here, but this bug goes even further. Sometimes Event.RENDER doesn’t even fire. In another related bug stop events on the first frame of nested MovieClip do not always work. Supposidly Adobe fixed this in version 9.0.45 of the player but as you can see by the comments on Emmy’s blog posting about the 9.0.45 release it was never really fixed. In fact we ran into this issue at work recently in the latest 9.0.115 version of the player.
I actually met with the Adobe Flash Player team last week and we discussed a lot of these issues, hopefully they will take these into consideration for the next release. To a developer they may seem like minor issues but designers and animators are going to have a difficult time getting around a lot of these bugs. If anyone else has any workarounds please feel free to explain them in the comments below.
P.S. this is my longest post ever, yay me.
By scott
Now that H.264 video is supported in Flash Player 9.0.115 and FMS 3 is on the horizon we are getting ready to flip on the HD switch in our video player. We have been lucky enough to try out a few beta releases of FMS 3 and have had great success with streaming H.264 video without too many changes to our core video player component (both AS2 and AS3). However, I ran into an issue yesterday with progressively downloaded H.264 video. The video would play but it was not progressively downloading, it would download the entire file before it began playing. Not the user experience we were looking for. The files played fine in Quicktime, and they played fine in Flash when streamed from FMS 3, just not progressively.
Time to hit Google. I found a few postings, not many, probably not too many people using H.264 yet (so I thought). Turns out the problem lies within the encoding of the file and where the “moov atom” is stored. The moov atom is essentially the header information of the file. To progressively play a file this data is needed before the first frame of video can play. This data contains the appropriate meta data the NetStream class looks at when determining the length, size, etc of the video. The moov data in my .mov files were stored at the end of my videos and that is why the video wouldn’t play until the entire file was downloaded. The moov data needs to be at the beginning of the file in order to progressively stream video.
I figured others must have run into this issue and someone must have wrote a utility to move the header bytes from the end of the file to the beginning. Byte manipulation isn’t rocket science, close, but not quite. While searching I found an interesting tech note on the Adobe site and it turns out Adobe’s own video editing software is to blame for this. The quote below is pulled directly from the tech note explains the issue.
“One important thing about playing an H.264 video file as progressive download is that the moov atom needs to be located at the beginning of the file, or else the entire file will have to be downloaded before it begins playing. The moov atom is a part of the file that holds index information for the whole file. Unfortunately, tools such as Adobe Premiere and After Effects place this information at the end of the file, but Adobe is working to fix this in a future update to the CS3 video production tools. This isn’t an issue for streaming the H.264 video files, however, so Flash Media Server users can breathe easy.“
Why didn’t Adobe address this issue? Obviously they rushed this feature to market, Silverlight supported H.264 video and everyone was raving about it. I don’t know if Silverlight progressively streams H.264 video when the moov atom is at the end of the file or not. Can anyone confirm? Or maybe this was some sick marketers ploy to entice users to buy FMS 3, i doubt that but conspiracy theories are so much fun.
Scouring the web I did find a utility that moves the moov atom to the start of the file. Renaun Erickson ported a C app to AIR that moves the moov atom and resaves the file. Very impressive! Unfortunately it didn’t fix my issues, Renaun’s app only works with .mp4 files and the files I was working with are .mov files. Using Quicktime Pro I exported one of the .mov files to a .mp4 to see if Renaun’s app would then move the moov atom. Still no luck. As a last resort I tried a simple Save As from Quicktime to see if it would restructure the bytes so the moov atom was at the beginning of the file. Guess what, it worked! My progressive downloads now worked. I created a simple batch and saved out all my progressive videos using Quicktime.
It baffles me that Adobe would not have put more thought into this problem especially when their own software is the culprit. They talk about CS3 suite integration and this is the furthest thing from that. Adobe mentions that they will be releasing a CS3 update to address the issue, hopefully sooner than later, unfortunately this does not help people (like me/us) who already have hundreds of H.264 assets with the moov atom at the end of the file. Re-encoding the video would be a huge process, we are already using the video assets for other streaming services, now that Flash supports H.264 we were hoping for an easy switch to our Flash video player. Most of our video is streamed, and that works great, unfortunately the progressively downloaded video wasn’t an easy switch.
In the end, the video looks great! Watching 1.2mb and 3mb fullscreen video in Flash is unreal. Now if we could just get support for variable bitrates!!
By scott
Well it’s a new year and I have held off posting anything. I didn’t really have a lot to say and I am not one to blog about nothing. A TV show about nothing was a huge success, but I can’t see a blog about nothing doing as well.
The past year has been a roller coaster for me and my family to say the least. We moved twice (4 times if you count corporate housing stops), one move was into a completely different country, I started 2 new jobs (Yahoo! and now Disney), my son went to 2 different schools, and somehow my wife found the time to get pregnant with our third child. So that means we won’t be resting anytime soon.
Looking back I wouldn’t of changed a thing as crazy as everything was. I learned so much professionally and personally. Professionally I have grown, my coding has improved greatly, for the most part I have been strictly working in AS3 and have absolutely no desire to turn back, unfortunately legacy code exists and AS2 will never go away, not for a long time anyway.
One of the best things of last year was working with Papervision, it has opened up a whole new world (or dimension) to me. I am a developer but I do have a creative side and being able to merge both halves of my brain using something like Papervision is truly amazing. Introducing the third dimension into interface design improves user experience because as humans we are trained to work with objects in 3D space and building everyday metaphors into the UI of our apps will make them that much better. Now if we could just get rid of the keyboard and mouse it would make obtaining those metaphors a lot easier. I think we are going to see a lot more 3D in the RIA space in 2008.
Last year we were all introduced to the iPhone, I am not going to drone on about it, but it truly is a great piece of hardware and software. Sure it is missing a few key things, but it is only a first release. Early this year Apple is releasing the iPhone SDK, you know engineers will be all over this SDK and it will only be a matter of time before some really cool apps and extensions are released for the iPhone. There is already a GPS extension in the works, GPS is the only thing I miss about my old LG phone.
So what else do I see happening in 2008. This is not a political blog so I won’t go into how I see the global economy switching from the U.S. dollar to the Euro, and I won’t go into the recession that everyone seems to be poo pooing which personally I think has already started. I also won’t go into how the Big 3 American car companies are digging their own graves and how the auto Unions are holding the biggest shovel. My all Chrysler employed family may disown me if I talk down the unions, oh wait, I think I just did.
2008 should be an interesting year from an RIA standpoint. There is a lot coming down the pipe. AIR is the first thing that comes to mind. Adobe has done a great job with AIR, I am just not sure how well it is going to take off out of the gate. In its current state it is a cool toy. I don’t think it is going to flop, I just think it will take a little time to fly, and maybe another major release. Personally I don’t agree with the whole AIR run time. I have used both mProjector and Zinc in the past to wrap swfs and create desktop applications. Both of these products allow you to create cross platform (Mac and PC, no Linux love) stand-alone apps with the Flash player included in the executable (if need be). These products had more hooks into the OS and file system, what they didn’t have was an embedded version of Webkit and a JS API. They also didn’t have the ability to interact with PDFs. So yes, AIR has it’s advantages, I just don’t agree with the runtime, it just adds a level of unnecessary complexity and doesn’t easily allow for easy deployment. IMHO. The apps should be stand alone so you can burn them on a CD and have them just work.
I mentioned the iPhone SDK already, this will be huge, of course people are going to try and monetize off of this, why wouldn’t they. What I am really hoping, as are most who are reading this blog, is the iPhone Flash Player we’ve been all dreaming about. There are rumors, lots of them, unfortunately only one guy (and probably a few hundred others) know for sure, Mr. Jobs, please enlighten us. The Internet on your phone is still a little watered down, you promised me the real internet in your ads, where is it? I know there would be memory issues, let’s face it, there are some very heavy flash sites out there. Already I have seen Safari on the iPhone close/crash when an image heavy page is loaded. By now I am sure most of you have heard about QVM or tamarin-tracing, could this be the beginning of something huge?
What else, Flex 3, all I have to say is wow. If you haven’t played with the beta do so now. The profiling and refactoring alone will blow you away. Flex has taken off big time, the one thing that puzzles me though is the number of recruiters who contact me with Flex work yet I still don’t see a ton of it out there in the tubes. Some of the jobs are with Fortune 500 companies. Either they are taking their sweet time to launch their “next big thing” or they gave up on using Flex because they couldn’t find the talent.
This year we will also see the Flex framework fully open sourced. Thank you Adobe, this is really going to change the landscape. Maybe we’ll finally see an AS3 decompiler.
EcmaScript 4, this is going to be an interesting one to watch. There has been a lot of rumblings from a few of the big players. Microsoft doesn’t like it. Once again, Microsoft and Adobe will be at each others throats.
IE8 will be released, yawwwwwwn.
Thermo, Astro, Buzzword oh my. H.264, Google Gears, WPF, it’s shaping up to be a good year. I have even heard some rumblings from the Cold Fusion camp, sounds like there is going to be some cool stuff coming from them.
I am not one to make resolutions, I believe if you have to wait till the beginning of the year to make a resolution you’re not very motivated. But this year I want to expand my horizons. I want to get into other technologies, I have played with a lot of things but I want to go beyond playing. Things like Ruby, Gears, Python. I want to get dirty with SQLlite. I also want to contribute more to the Open Source community. I also don’t want to move, don’t want to start a new job and maybe want to take a vacation for the first time in 4 years. We’ll see how much of this list I get to, with a third child on the way it could be tricky.
In closing, Happy New Year to all, I hope you and your families have a great 2008.
Filed under:
AIR,
Actionscript,
Adobe,
Apollo,
Apple,
Disney Internet Group,
Family,
Flash,
Flex,
General Programming,
Papervision3D,
Technology,
Whatever,
Yahoo
By scott
A short time ago, almost a year now, I blogged about how I was leaving Critical Mass to go and work on the Yahoo! Flash Platform team. Well, believe it or not, I am on the move again. This time I have accepted a job with the Disney Internet Group in North Hollywood. Just like Yahoo! I will be a Senior Flash Engineer working on the core technologies team. I am not sure who is more excited about me working for Disney, my son or me?What excites me the most about this opportunity is the creative environment I will be working in. Those who know me know that I thrive in a creative environment, and it doesn’t get much more creative than Disney. I love to push the envelope and one thing I have learned over the past 10 years is it takes a great creative team and environment to push development teams to the next level.
Yahoo was great, I learned a lot, met some great people, and I worked with some of the smartest people I have ever had the chance to work with. Plus I got to see Taylor Hicks in concert at the Yahoo! campus, oh wait; I am only supposed to be mentioning the good memories.
I would like to thank Yahoo for the great opportunity they gave me and everything I learned. There are some very talented people in Sunnyvale and around the world painting the internet purple. Do you Yahoo? I did and it was spectacular! (obscure Seinfeld reference for you hardcore fans). Now I must replace my Yahoo! hat with a pair of ears.
