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For a quite long time I was used to use the Flash Builder (previously called "Flex") enviroment to build complex applications, and in my current project (cant say what project is, sory) Im part of a RIA made in Flex, using mxml, AS3, some JS, etc.
The performance is below average.
The site feels like u need a powerful PC to run it something close to smooth.
And Im working with very talented ppl here, or at least thats what I can perceive.
So my question is, there is a posibility that the next version of the website will be made in pure HTML + CSS + JS, to obtain a more responsive feeling when u use the site, is something at least close to what FB can do for you in terms of a project-oriented enviroment?
On another hand, this general laggy and low performance thing is a programmer related issue, or it cant be avoided since "its just Flash" ?
Thanks!
(Im a big fan of flash tbh, but I try to keep my mind open in this)
Everything depends on what you're trying to do and if your programmers know how do to their jobs. If they don't take care, then it's very easy to create an application in Flash, and especially Flex (as you really need to know the internals of Flex to understand what it will do and when), that saps memory and power so that you need a beast of a machine to run it. Optimisation is a large topic, but fortunately, the web is covered in links on what not to do, or tips on how to use Flash to it's full potential.
As a quick test, open up the task manager, then run your app (close down all other programs using flash, including gmail, web radio etc), then watch the memory usage. If it's continually climbing, then there's a problem in your code.
Alternatively, if you have a bit more time, build some debug tools into your app so you can see what's going on in terms of framerate and memory usage - try the FlashPreloadProfiler for a quick fix: http://jpauclair.net/flashpreloadprofiler/
If your app shouldn't be complex but it's lagging (by complex, I don't mean the actual purpose of the app, but rather what it's showing on the screen, effects etc), then the problem is that there's misuse somewhere.
Go the HTML5 route if you feel it's the best solution for your site/app, but you'll probably encounter the same problems. In some situations, it's slower, in others Flash wins by a country mile. Again, it comes down to the devs
We built Dedoose in Flash Buidler 4, check it out... the performance is freaking great, and it's is a GIANT web app that handles an enormous amount of data. Flash Player in general does have performance problems, but with great engineering and knowledge of how to squeeze good performance out of it, I personally do not see a better alternative, excerpt for maybe silverlight if your requirements fit. For guidance on performance improvements a good place to start is all of Grant Skinner's articles over at http://gskinner.com/blog
Additionally, I can't really see what the actual question your asking is, what are the alternatives? HTML5+CSS is good, but good luck getting any good productivity out of your team developing a large scale web app in it. Silverlight is pretty dang good if you can force plugins down the users throat, Java is suffers the same dilemna. Personally I would read up more on getting good performance out of flash, then learn exactly how the flex framework works in terms of what it builts upon flash with, then... if u want real performance, ditch most of the flex framework and use things like MinimalComps and custom built components. Have you used the Flex Builder Profiler to analyze where your slow downs are occuring?
~ JT
If it's just an IDE you want, I'll give a nod to Flash Develop: http://www.flashdevelop.org/wikidocs/index.php?title=Main_Page
Not all the power of Flash (Flex) Builder, and without the design view. But it's free, open source, and community driven. I personally prefer the style of context highlighting and code completion hints in Flash Develop.
I'm looking into creating a Rich Internet Application. For the interface, I want something smooth, fast, and robust. I realize there are several technologies out there to do just that (Flex, standard HTML/Javascript, Silverlight).
After using Grooveshark, I am very impressed with its interface (written in Flex). Personally, I don't think I have seen an interface written in standard HTML/Javascript that is that visually stunning, smooth, and fast.
However, I have heard many arguments against using Flex with many believing Flash will eventually fade away.
Anyway, I have seen solid applications built with each, and I know a decision can depend on many things. But, in general, what are the pros/cons for each technology and which one would you ultimately choose for your RIA?
NOTE: This would be an open web application with the intended audience being anyone. It's not being built for specific client(s).
I would make the decision based upon my client(s). For general "web stuff", I still am opposed to RIAs (I think they have more of a purpose in a rich client to a particular market, e.g. business -- or filling out online taxes returns -- and not general pleasure/browsing/navigating/site).
As far as Flash "fading away" -- haha. Yeah, right. We still have COBOL and Shockwave. A product with 99%+ market dominance (depends on market, of course) is hardly bound to "fade away" overnight. When the "eventual" does come, nobody will care about this next RIA project of yours anyway :-)
with many believing Flash will eventually fade away
Sure, just like any technology, Flash will fade out at some time. But that won't happen in the near future, so it would be a stupid argument not to use Flash (in the same way you could stop developing things for »insert any technology here«).
I know this won't be a real answer as you want some more comparison of the current RIA technologies, but it is hard to do that anyway. In some way, you can build any application with both Flash and JavaScript. For more complex application both will require quite a lot customization to get the application running the way you want it. At that point Flash might have a small pro point given that you have a bit more powerful language with it than JavaScript (which still has performance problems depending on the browser, while Flash is more or less stable), and generally don't need to build anything on HTML's elements. But in the end, you can stil do it with both, so maybe you should decide based on your actual knowledge with the respective language instead (or base the decision on the client).
I think you are right in saying that Flex/Flash applications far outshine their HTML/JavaScript counterparts as far as UX is concerned. However, the main drawbacks are mobile and accessibility. Flash currently has poor reach on mobile platforms, but that shows signs of improving. Also I don't think most screen readers can deal with Flash. Silverlight is probably just as good, but it's not used as much and does not have nearly the user base of Flash.
I don't think I have seen an interface
written in standard HTML/Javascript
that is that visually stunning.
I'm not a big fan of writing raw HTML/JavaScript because it's SO much effort to make it look as slick as some of the Adobe stuff. However, there are some pretty decent frameworks and abstraction layers that let you get a visually stunning front-end, and let you write the while thing almost exclusively in Java. I've had success with SmartClient/SmartGWT in the past to make an iGoogle-esque portlet web application.
Pros: Google Web Toolkit + Eclipse is free, don't have to write much raw HTML/JavaScript, saves a TON of dev time, aren't locked in to an Adobe product, GWT compiles to HTML+JavaScript and is absolutely universal
Cons: the high-end professional and enterprise versions are not particularly cheap (~2K USD)
HTML+CSS+Javascript is a good solution. And maybe you should consider your RIA can across device and platform. Test some javascript framewoks first, especially those with RAD UI Tools, For example, CrossUI.
Nowadays, RIAs should migrate to full JavaScript UI with CSS skinning.
The task of building the UI should be analogous with these of the old tools like Visual Basic or Borland Delphi. This means almost entirely configuration instead of hand-writing the interface code.
You should also consider choosing a consistent widget set the follows the way of web components, i.e. inheriting from Element to always stay in sync with browser technology changes.
Here is a tool to help you evaluate several frameworks:
https://sourceforge.net/projects/jul-designer/
Remember, following the standards and eventually anticipating them, is the best way to go.
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I'm fairly new to this whole web-development thing (2 weeks maybe, my 1st scraping of code exists here, I quite like it) and I ended up learning to use Adobe's Flash Builder 4, which I have come to quite like (although Action Script annoys me at times).
Recently however I've been reading a lot about "the future" of web development, RIAs, web 2.0 etc, and it appears the whole Flash/Flex/ActionScript frame work's main competition will be the HTML/CSS/JS stack (or "HTML 5").
So obviously I don't want to take the time to learn a language (Flash/Flex/AS3) that will end up dead in a couple of years and end up having to learn another one (HTML/CSS/JS), when I could just move over now.
My main interests are fairly information rich (database orientated) web sites, with high levels of user interactivity for customisation, uploading, etc. I like the whole mobile web aspect, and would like to have the capacity to also develop for that platform, as well as mobile apps etc. I love the whole "live" aspect (like the tour de flex light up map that shows user activity), not particularly bothered by uber complex animation and obviously want things to be responsive and user friendly.
So yea, any input on this would be much appreciated, I'd just like some advice for overall direction for my personal learning and development.
Thanks!!
You're making some basic mistakes in the question. The HTML/CSS/JS combination is different from HTML 5, That combination works just fine with current implementations (ignoring some of the annoyances of IE for the moment.) HTML 5 is a new extended definition of HTML with a number of new features like local storage.
HTML 5 is also not completely settled, nor completely supported.
You should learn HTML and CSS to start with; in general, you still need a web page in which to embed your Flash stuff. You should get some basic knowledge of Javascript for much the same reason.
Conveniently, the Javascript will carry over to Actionscript, which is a variant of the same ECMAscript standard.
Flash isn't going anywhere for a long time, and given the glacial pace that the HTML5 committee is working at, the HTML 5 spec won't be fully standardised for a while yet either.
Plus before all these lovely HTML5 web apps can become commonplace, the world's windows users will need to have a better browser than internet explorer 8. Given that 10-20% of web users are still stuck on IE6, i don't think we'll be seeing html5 becoming dominant for quite a few years. Of course then by that time we'll be seeing HTML6 and the slow painful process of getting the world to upgrade will start again.
Personally i don't do flash, because for what i do i really don't need it, but flash is a really useful tool outside of web development too. Lot's of triple A Games have flash built menu's and user interfaces for instance.
But really, become good at either/both technology, and you'll probably not be short of work
Learning a language like Actionscript can never be a waste of time , the mindset you will develop from it will enable you to understand the concepts of programming and it'll be easier for you to move to other languages if/when you so desire. Learning HTML & CSS is essential if you plan to develop for the web but it will not bring you the same type of knowledge, as it uses a very different logic. If you like the idea of developing web applications, one day you may want to develop desktop applications, HTML won't be of much use then, whilst the programming knowledge acquired with AS3 will not be lost.
Is this just for the fun of learning, or do you have any specific tasks to accomplish? I like to use the correct tool for the job. If you don't have a specific job to accomplish, or any constraints to work under, I would just pick the most marketable skill and go with that. Unfortunately, I'm not exactly sure which is the most marketable skill.
My recommendation would be to check out some JSON type stuff in JavaScript. That seems to be a pretty stable (might I even say fad-resistant) AJAX evolution which is pretty wide spread and likely to stick around for a while. If you focus on the high level theoretical concepts, the specific comings and goings of implementations won't be as important (in my opinion).
I think learning AJAX (using JSON rather than XML) is a good way to go so you learn about implementing asynchronous information rich sites. If you have to redraw the site entire site when you pull information, you're doing something wrong. The AJAX concepts will come in handy regardless of your platform.
Good luck!
-Brian J. Stinar-
Don't bother with flash.
Yes, it's pretty and powerful and fairly ubiquitous. It's also on its way out the door, as you observed in your question.
Let's compare Flash and its newly-arrived competitor, the HTML5 canvas element.
Flash is only supported by Adobe; if you want quality development tools or resources you'll have to buy from them (for the most part).
HTML5 canvas doesn't need proprietary development tools. HTML5 canvas is supported by every major browser vendor -- Mozilla, Apple, Google, Microsoft. All vendors will provide documentation and competition for each other, which should result in a more refined product.
When OpenGL support (direct gfx card access) was in discussion for HTML5 Canvas, guess who was the only holdout? Adobe, of course. Everyone else wanted hardware graphics support for canvas.
In other words it's Adobe against everyone else here, and Adobe's not going to win. They might keep the status quo for a while, but eventually they'll lose their foothold and canvas & co will take over.
tl;dr: No use learning the dying proprietary technology when you can learn the modern open technology that's going to replace it.
HTML5 is still very unstable, so you shouldn't try it.
For me, HTML5 is great, but some business haven't moved off of IE6, given its current state. Flash, while useful, can be very very tedious at times and other times it doesn't even work on some computers or makes some computers truly a pain in the "insert word here".
It's better to start with CSS and HTML4. Get the basics, then start going for more.
By then, you'll know what to want.
Personally I think all the answers here are overcomplicating things. Here's my take:
Use whichever technology excites you, and is best for what you want to build right now.
If the app you want to build right now feels perfect for Flex, use Flex. If something about HTML5 has caught your fancy and won't let go, dive into it. You can always change technologies in a year or three, and You'll be taking everything you've learned about design and architecture and usability with you - learning a new scripting language and some new tools won't be that bad. The only way you can make the "wrong" choice here is if you, for whatever reason, pick a technology that you wind up not enjoying enough to get anything built.
The reason I feel this is the best way is, nobody here can tell you anything useful about what technologies will or won't be around in a few years' time. Adobe could go bankrupt; Steve Jobs could die; Google could get broken up in an antitrust suit. Hell, Flash could be on the iPhone next year for all we know - or HTML6 could adopt a new, strongly-typed JITable programming language. Or a hundred other things could happen to render your (and our) predictions moot.
I mean, personally I expect that both Flash and HTML5/6/7 will be vibrant and flourishing in five or ten years - because they both have successful organizations behind them investing in their futures, and because I've never heard a whit of a meaningful argument why the success of one should require the failure of the other. But that's just a guess, and my guess is no better than yours. Focus on getting good stuff made now, and the technology road map of the future will come when it comes.
In my opinion – everything is worth learning, especially when it comes to HTML/CSS/JS/Flash, which are each completely different systems/skill pools tailored to entry-level developers.
HTML is tagged markup, and very important because it outlines XML usage. CSS is writing visual formatting rules. JavaScript is a scripted language, and a great way to get your feet wet with simple programming logic. And Flash is a great system in which to get into object-oriented programming within a compiled language.
As you keep venturing out, you'll find that a lot of technologies are really just different flavors of the same ice cream. While different languages have their own nuances, there are fundamental similarities between –say– most compiled languages. I came from Flash and got into iPhone development... while Objective-C is a way bigger and uglier system to dive into, I still generally knew my ass from my elbow while building my first app after several years experience with AS3. The same goes for .NET and Java. Also, I would second the notion that Flash is not dead, despite loosing traction in the wake of the iPocalypse. Whether it dies in a few years or not, it doesn't make AS3 any the less valuable to have learned in addition to HTML/CSS/JavaScript.
We currently have a quite complex business application that contains a huge lot of JavaScript code for making the user interface & interaction feel as close to working with a traditional desktop application as possible (since that's what our users want). Over the years, this Javascript code has grown and grown, making it hard to manage & maintain and making it ever more likely that adding new functionallity will break some existing one. Needless to say, lots of this code also isn't state of the art anymore.
Thus, we have some ongoing discussion whether the client-side part of the application should be written anew in either Flex or Silverlight, or written anew with some state of the art JavaScript framework like jQuery, or whether we should simply carry on with what we have and gradually try to replace the worst bits of the existing code. What makes this even harder to decide is that writing the UI anew will probable cost us 6-12 person months.
I'd like to hear your thoughts on that issue (maybe some of you have already had to make a similar decission).
EDIT: To answer some of the questions that came up with the answers: The back-end code is written in C#, the target audience are (usually) non-technical users from the companies we sell the software to (not the general public, but not strictly internal users either), the software 'only' has to run in desktop browsers but not necessarily on mobile devices, and the client app is a full-blown UI.
In all honesty, I would refactor the old JavaScript code and not rewrite the application. Since you are asking about which platform to put it in, I would guess that your team isn't an expert in any of them (not slamming the team, it's just a simple fact that you have to consider when making a decision). This will work against you as you'll have double duty rewriting and learning how to do things on the new platform.
By keeping it in JavaScript, you can slowly introduce a framework if you choose and do it iteratively (Replace on section of code, test it, release it, and fix any bugs). This will allow you to do it at a slower pace and get feedback along the way. That way too, if the project is canceled part way through, you aren't out all the work, because the updated code is being used by the end users. Remember the waterfall model, which is essentially what a full swap out of will be almost never works.
As much as I hate to admit this, as it is always the most fun for developers, shifting platforms, and replacing an entire system at once rarely works. There are countless examples of this, Netscape for one. Here is the post from Spolsky on it. (I would also recommend the book Dreaming in Code. It is an excellent example of a software project that failed and how and why). Remember to rewrite a system from scratch you are essentially going to have to go through every line of code and figure what it does and why. At first you think you can skip it, but eventually it comes down to this. Like you said, your code is old, and that means there are most likely hacks in it to get something done. Some of these you can ignore, and others will be, "I didn't know the system needed it to do that."
These things spring to mind:
As you have a .Net backend and you have some ability to force your customers onto a specific platform, Silverlight is an option;
Since your client is a full-blown UI you want widgets and possibly other features like Drag and Drop;
I haven't seen any requirements that to me would justify starting over (which often doesn't work out) in Flex/Silverlight (eg streaming video, SVG support. Added to your team's familiarity with Javascript, I think you can't make a compelling case for doing it in anything other than Javascript.
But of course Javascript is lots of things and there are [lots of Javascript frameworks1. The most important divider is whether your intent is to "decorate" a set of Web pages or you need a full set of Widgets to create a desktop-like application on the Web. Your question indicate it is the latter.
As such--and I may get downvoted for saying this--I don't think jQuery is the answer and I say this as someone who loves jQuery. jQuery (imho) is great to enhance Webpages and abstract cross-browser low-level functionality but the most important factor for complex UI developer is this:
It's all about the widgets.
And yes I'm aware of jQuery UI but it's a lot sparser than the others when it comes to widgets. I suggest you take a look at the samples and widget galleries of some frameworks:
YUI Examples Gallery;
ExtJS demo; and
SmartClient feature explorer.
The others (jQuery, Dojo, Mootools, Prototype) are more "compact" frameworks arguably less suited to your purpose.
Also consider the license of each framework when making your decision.
My thoughts on the above three are:
ExtJS has somewhat angered the community in that it started out as LGPL but had a controversial license change (that thread is at 76 pages!) to GPL/commercial at version 2.1. The problem with that the community no longer has an active participation in the framework's development. Not the mainline version anyway. This means it's being developed and supported by a small team (possibly one person) rather than the community. IMHO it's not worth paying a commercial license for that and GPL is probably prohibitive in your situation;
YUI is supported by Yahoo and available under a far more permissive and far less invasive BSD license. It's mature, well-used and well worth serious consideration; and
SmartClient impresses me a lot. It has perhaps the most permissive license of all (LGPL), is roughly seven years old, has an incredibly impressive array of widgets available. Check out their feature explorer.
Your decision should be based on how you get as much of your application "for free" as possible. You don't want to spending valuable developer time doing things like:
Coding UI widgets like trees and accordions;
Testing and fixing cross-browser Javascript and CSS issues;
Creating homegrown frameworks that greatly duplicate what existing frameworks do and do well.
I would seriously look at one of the above three as your path forward.
This decision is usually less about the technology, and more about your skill sets and comfort zones.
If you have guys that eat and breathe Javascript, but know nothing about .net or Flash/Flex then there's nothing wrong with sticking with Javascript and leaning on a library like jQuery or Prototype.
If you have skills in either of the others then you might get a quicker result using Silverlight or Flex, as you get quite a lot of functionality "for free" with both of them.
My opinion on this one's pretty simple: unless the app needs to be accessible publicly, unless it needs to be search-engine optimized and findable, and/or there's an otherwise compelling case for its having to remain strictly text-based, then the chips are stacked in favor of rich-client runtimes like Flash or Silverlight right out of the gate.
A big reason, if not the biggest, is that they eliminate the complexities of developing for multiple browsers and platforms. Again: they eliminate the runtime-environment variable. No more debugging old versions of Netscape and IE, no more object detection and consequent branching, no more wacky CSS hacks -- one codebase, and you're done. Offloading the runtime environment to Adobe or Microsoft will save you time, money and headaches, all else equal. (Sure, there's YUI, JQuery, etc., but they don't eliminate that variable -- they just abstract it. And they don't abstract all of it, either -- only some of it; ultimately, it's still up to you to test, debug, retest, debug, repeat.)
Of course, your situation's a bit more complicated by the existing-codebase problem, and it's difficult to say definitively which way you should go, because only you've got the code, and we're just geeks with opinions. But assuming, just by your asking the question, that a refactoring of your existing codebase would involve a significant-enough undertaking as to warrant even considering an alternative (and probably comparatively foreign) technology in the first place, which it sounds like it would, then my response is that your curiosity is well-placed, and that you should give them both a serious look before making a decision.
For my part, I'm a longtime server-side guy, ASP.NET/C# for the past several years, and I've written many a text-based line-of-business app in my time, the last few with strong emphasis on delivering rich soverign UIs with JavaScript. I've also spent the last couple of years almost exclusively with Flex. I've got experience in both worlds. And I can tell you without hesitation that right now, it's everyone else's job to beat Flex: it's just an amazingly versatile and productive product, and for line-of-business apps, it remains leaps and bounds ahead of Silverlight. I just can't recommend it highly enough; the data-binding and event-handling features alone are incredible time-savers, to say nothing of the complete freedom you'll have over layout, animation, etc. The list goes on.
So, my advice: take a long, careful look at Flex. In the end, you might find a ground-up rewrite is just too massive an undertaking to justify, and that's fine -- only you can make that determination. (And to be fair, you've just as much ability to make a mess of a Flex project as you do with a JavaScript project -- I know. I've done it.) But all told, Flex is probably the least-limiting, most flexible, most feature-rich and productive option out there right now, so it's certainly worth considering. Good luck!
Any javascript you have that has been developed 'Over the years' probably doesn't look anything like what's possible today. You undoubtedly have a lot of useful code there. nonetheless. So my recommendation would be re-write in javascript using jQuery and make use of one of the available GUI add-ons, perhaps look at Yahoos stuff. You will also be targeting the widest audience this way.
The GUI technology should be first and foremost determined by your target audience. For instance, if you target englobes iPhone users, I would not recommend Flex, because iPhone doesn't have a flash player at the moment.
Bear in mind that if you switch to a full fledged GUI toolkit like Silverlight, your users may find the L&F unnatural, since the usual request-reply cycle is not so evident with client-side frameworks.
After that, it is your developers that should have a word to say. Every toolkit needs maintenance, and if you are switching to a whole new toolkit the developers will have to familiarize with the new toolkit, which can be costly.
My suggestion is that you stick to javascript, since your devs are familiar with it, and gradually replace the old javascript with a new toolkit like prototype, jQuery or any other. You will probably redo some of the old stuff faster using a state-of-the-art toolkit. Remember that you can build beautiful apps with any tookit.
We have developed an extremely rich application using EXTJS with C# and a some C++ on the server. Not only do we have clients who are happy with the interface in their desktop browsers but with very little tweaking to the Javascript we were able to provide web browser support. Also, we have clients in third-world countries who cannot use Flash or Silverlight apps due to their field personnel using kiosks in internet cafes (many of which don't have Flash installed - forget Silverlight!). I think these issues and others make up for the difficulty of coding a complex app in javascript...
Check this comparison table for Flex vs Javascript:
I'm going to develop a comprehensive educational software which runs on the browser and has many visualization and simulation works (electrostatic and electromagnetic visualization, 2D and 3D).
Which language(Processing, javascript or something else) is the best toward my purpose?
The question is indeed broad but I will answer from the experience I've had.
Javascript is not really meant to do mathematical calculations, which is what might be necessary to calculate a lot of E&M phenomenon quickly (Especially if they are not represented as a closed form solution). It really goes into how much detail you want in your graphs as well (More steps = more calculations). You may find yourself needing to do more optimizations to make up for the performance difference.
I did some visualizations of antenna arrays (They had closed form solutions, only simple arrays) in Flash and it worked out ok. Javascript will definitely not be up to par with any 3D simulations you might want to do.
I wonder if Silverlight might be a better solution, because you may find more mathematics libraries for .NET than for Actionscript, that could save you a lot of work of writing the math out yourself (But you might end up doing this anyways because of the performance issues).
As others have suggested javascript is not that strong of a language when it comes to visualization.
Processing is a really good language for what you're trying to do, it's easy to learn and is Java based. Data visualization is built directly into the language, as well as temporal space (ie advance "1 tick" in time and have the visualization react to that.)
Also if you're interested in going that route I'd suggest picking up Visualizing Data which is pretty much a Processing primer.
Flash may be the more common application stack right now for what you are looking for, but Silverlight is looking primed to take the title from them based on the powerful features that it contains.
I would go Flex or Silverlight myself
Plenty of re-usable libraries
Native support for multimedia
Native support for graphics and animation
I'm a little late to the show, but what you want, has been implemented in JavaScript, and you'll find this incredibly useful. I recommend running it under Chrome as the JS processing engine is extremely fast. (You may even want to try Chrome 2 which is even faster)
http://ejohn.org/blog/processingjs/
http://ejohn.org/apps/processing.js/examples/basic/ (91 basic demos.)
http://ejohn.org/apps/processing.js/examples/topics/ (51 larger, topical, demos.)
http://ejohn.org/apps/processing.js/examples/custom/ (4 custom "in the wild" demos.)
See also: http://www.chromeexperiments.com/
I second LFSR Consulting's opinion: Processing is used a lot for educational purposes, it is free, and fast (Java is faster than Flash in general) and easy to learn, so you have faster results. It supports 3D, you can tackle Java libraries for simulation and computing, etc. And it has a great community! :-)
JavaScript is a bit light for such usage. JavaFX is hype, but it hasn't really 3D (although one used Java3D with it) and it is still a bit young.
Flash and Silverlight: no comment, not much experience in the field. OpenLazlo can be an alternative...
You really have two choices ActionScript in Flash or VB.NET/C#/other in Silverlight.
So first you need to decide which of these platforms you will target.
You may be able to split the problem into two parts, the user-interaction and display part, and the heavy calculations part.
If you can move the heavy calculations to a server then you can still show everything in javascript.
One difficulty with javascript is that it is interpreted and you will need to write more of the equations yourself, so there is a performance hit and development time, but it will work without any plugins, unless you don't want to do 3D in the canvas tag.
Flash and Silverlight may have better options, but then you are learning new languages and requiring plugins, depending on what version of Flash you want to use.
Check out processing.js, xcode, and iprocessing!
ProcessingJS is great for data visualization but lacks in interactivity.
You should probably try python. It is a really good language for educational and computational purposes it has a pretty decent community and the syntax is not so tough. Even though it was designed to for command line you can create front end gui's for it using some external package and it also provides packages like Scipy, Numpy and Matplotlib for advanced plotting and data visualization.