I am developing a web-based simulation where I want the front-end to be "animated" in real-time--it will be a mapping application, and I want to have little icons (representing the components of my simulation) moving all over the map as the simulation runs. I am developing the back-end in Rails, but I am wondering what are good packages to use for the front-end / animation part? I used Graphviz to generate the base map (a directed graph), but it doesn't seem well suited for live animations.
Something like Hans Rosling's Gapminder (if it's even possible to do in real-time). Or should I be doing something similar and "recording" the data then playing it back? What packages should I consider in that case?
Gapminder
Currently using Rails 3.0, Ruby 1.9.2, Graphviz 2.28.
Here are 2 javascript libraries that may help. You could use ajax calls to your rails backend to populate their data. I'm unsure if D3 has mapping capability, but I believe Raphael does. As far as real-time, you'll have to check out their documenation. In Rails 4, I believe the streaming capability may benefit you as well, but I've not investigated.
Raphael
D3
Related
I am working on enterprise-level business applications, and now is the time to start thinking about the non-desktop experience.
We have a common component code-base that is using dojo, and are trying to get as much code re-use as possible.
I am really struggling to determine if I should re-use the same code base, or have separate code bases for desktop and mobile.
A big factor in my decision making is the viabliity of dojox/mobile.
It seems pretty cool, and uses the dojo infrastructure which is a huge win, but the fact that it is in dojox scares me a little.
Some questions:
Is dojox/mobile something that can be relied on long term?
Is it a smart idea to try to swap out dijit components for dojox/mobile components depending on what has.js can tell me?
Will dojox/mobile be a part of dojo2.0?
I would add that in Dojo 2.0 the plan is to converge as much as possible the desktop (dijit) and the mobile (dojox/mobile) widgets which should help in your use-case. See: http://mail.dojotoolkit.org/pipermail/dojo-contributors/2013-June/029041.html
You can rely on dojox/mobile. DojoX will indeed disappear from the Dojo Toolkit in 2.0, but most matured (and probably maintained) modules will be pushed to the dijit/dojo library. I quote the reference guide:
In the future (Dojo 2.0), the DojoX package and namespace will
removed. Sub-Packages and modules will be either integrated into the
Dojo Core, Dijit or separated as their own stand-alone package. For
the 1.X code stream though, in order to ensure backwards
compatibility, all these packages are contained within the dojox
namespace and package.
If we look at the explanation of Mature, we can read the following:
This package or module is considered mature and is being actively
developed and maintained by committers within the Dojo Toolkit. It is
expected that it will persist into the foreseeable future.
Source
And if you look at the link above, you will notice that dojox/mobile is categorized as mature.
Another reason you can rely on it is that IBM (which can be considered a pretty big company and committer to the Dojo toolkit) also relies on dojox/mobile for their mobile product called IBM Worklight. If they rely on it, then there's no reason you couldn't.
I don't think it will be easy to start from the same code base and swap out dijits for dojox/mobile components. Usually mobile app development requires an entire different strategy than web applications. You will probably have to split certain things into multiple views and some dijits may not have a mobile alternative.
You can probably re-use most of your utilities and business logic, but I think you will have to start from scratch again if you want to write your view(s). But I'm not really an advanced mobile developer.
I want to develop an application for Mac OS X to record audio from one application.
I played around with Soundflower, but it only grabs the full system audio.
I know that I have to use a HAL plug-in. This plug-in is loaded from an application that uses Core Audio and then I can communicate with the plug-in to grab the audio.
My question is: How does such a plug-in look like? Are there examples on the internet? I have not found anything about this topic.
Now that you've decided that using Cocoa injection is a feasible solution to your problem, let's start there.
What you need to do is find out how the ObjC classes in the app are setting up to play audio, and hook in to set a different AU in place of the default system out.
There are two options (besides writing your own custom AU from scratch, which you don't need to do). You can use AUHAL as the AU, and capture the data from AUHAL. This is a bit easier from the point of view of hooking things up, but it means you have to write the code that renderers and saves the audio. Or you can just hook in a save-to-file AU, which is a bit harder to hook up, but once you do it takes care of rendering automatically.
So, how do you hook things in? Well, most of the higher-level CA calls are written to just write to the current output. If the app is doing things that way, you just need to hook in at startup to find your replacement AU and set it as the current output, in place of the default. On the other hand, if the app is writing directly to an AU that it stores in a variable, you have to hook it to store your AU as a variable. And if it's building a graph of AUs, you either replace the default output, or stick yours in front of it, in the graph.
See TN2091 for some sample code fragments for most of the hard parts for most of the possibilities. It doesn't show you how to put them together, and it's got a lot more about setting inputs than outputs (because that's harder), and the terminology can get confusing, but if you read it carefully, you should be able to find the parts you need.
If you haven't yet built a simple AU host and AU plugin before, you really should take the time to work through the whole Audio Unit Development Fundamentals guide. (And if you don't think you really need to know all that to do something simple, you're wrong. Why CoreAudio is Hard explains half of the reason; the changes between OS X versions versions are the other half of the reason.)
You probably also want to look at CocoaDev's CoreAudioAndAudioUnitsTutorial page for a placeholder page for a complete tutorial that nobody's ever written, with links to a lot of useful stuff.
Meanwhile, if injecting the whole MTCoreAudio framework into the app is feasible, it comes with a ton of nice, complete samples. In fact, even if you aren't going to use the framework, it's worth reading the Overview documentation, and possibly the source code.
Assume I have a running ruby on rails app.
I’m creating classes (db-models) defined by a description provided at runtime.
Right now, I’m using the rails app (via browser) to trigger the code generation — and therefore the app “knows” about its new classes.
But, is it possible to inject code from scripts executed inside the rails app directory?
Like…
$ [path/to/app] rails s
$ [path/to/app] script/apply_schema
Since RoR supports many helpers for both generating tables, columns etc. I do not see why you want to do this using script injection. this would not only be a very weird way of inputting and rendering data but it would also create quite a security risk.
Then comes my second question (in runtime) how would you define authentication? since you are trying to inject code?
I would advise using the SQL helpers to create/update/destroy attributes. this is based on a much used and effective architecture. also using relations makes you able to build quite alot while still remaining in the "safe" environment RoR offers.
If you want to try a framework wich offers data injection on runtime try Meteor
I've been looking over Sproutcore, Ember and Blossom and other competitive framework efforts (e.g. Sencha) to select for a HTML5 client side application project. The state, information, and documentation from these projects is a bit fragmented and in need of clarity, so I am presenting this to the community.
My project is to be a native-like HTML5 application with desktop level complexity in need of a complete application framework, that will work well on desktops and run with good speed on mobile devices with touch awareness. The widgets should be native-like (not web-like), but customizable so to be unique to the application.
Questions/framework Requirement:
Native vs. Web style Applications. Framework should make it easy to
build native-like user experiences with the ability to make a custom
native feel (not just wholly imitating mac/win/iOS). Some of the text
surrounding Ember indicates it is really meant for web-style apps - which given no
UI layer maybe goes without saying. Frameworks like Sencha, can it easily accommodate custom widgets?
Mobile Appropreatness. Framework should be appropreate for mobile devices and have facilities for touch input and
gestures.Several notes I've seen in my research indicate that Sproutcore and
Blossom aren't very appropreate for mobile, and that Ember is better
geared towards mobile (size?). It isn't clear whether the
touch/mobile libraries are very developed in Sproutcore/Blossom and if they will be supported it the
current state going forward. (and blossom compile to native is not acceptable). On the otherhand, Frameworks like Sencha, do they have the facility to work well on desktop as well as mobile?
Framework Completeness. The framework should be a fairly complete application framework, with desktop-like OO expectations and management for automatically and efficiently syncing, managing, and serializing the data model with the server. Not sure if there is much difference between Ember and Sproutcore, how do other efforts like Sencha stack up?
Your question covers a lot of ground. I will pick some quotes and answer them directly.
My project is to be a native-like HTML5 application with desktop level
complexity in need of a complete application framework
Ember.js specifically bills itself as a "web-style" framework, not a an RIA framework. That said, you can build anything you want, but you would be trailblazing.
Sproutcore bills itself as an RIA framework. You have complete control over the DOM, so if you can do it in the browser, you can do it in Sproutcore.
Ext-Js is also a good application framework for desktops (Sencha Touch is for Mobile). If you like the way its examples look, then its a good choice. You can of course customize the dom and write your own widgets.
Blossom is basically Sproutcore with a canvas based view layer. It just went into beta, so you would definitely be trailblazing if you went with it.
So, you can basically use any of the frameworks you mentioned for the RIA part of your enterprise. I would eliminate Ember.js simply because the framework itself purposes itself for web-style (e.g. twitter) as opposed to RIA (e.g. iCloud) apps, which is not what you want.
The widgets should be native-like (not web-like), but customizable so
to be unique to the application.
All three of your remaining options can do this. If you like Senchas widgets, its a good choice. I don't know if they are native enough for you. That said, with any of the remaining frameworks you can customize the DOM to your heart's content.
Mobile Appropreatness. Framework should be appropreate for mobile devices
This is a tough one. Sencha Touch (which is separate but similar to Ext-Js) is very popular and gets the job done. It is performant too; a non-trivial app ran fine on my original Droid (which surprised me).
Sproutcore is very heavy weight. It has mobile support (i.e. for touch events) but you need to very careful about the dom you create, so as not to overwhelm the browser. I wouldn't choose Sproutcore for mobile, although you could if you are very careful.
and blossom compile to native is not acceptable
That does not seem reasonable to me. To be clear, NONE of these frameworks run natively on mobile devices; they ALL run in the browser. Blossom comes closes as the canvas API is mapped directly to the native API, giving you a truly native app. The only way you could get closer would be to use objective-c/java for iOs and Android.
So basically, at this point your left with Sencha(Ext-Js) and Blossom. Blossom is still in Beta, you would be trailblazing if you tried it. Sencha is established, has great support (Blossom support is good on irc), and a large developer base.
So Sencha is the choice, unless you really want to be cutting edge, and take a little risk.
Troy. Indeed, ember can run with another view layer framework such as jQuery Mobile which can provide a "app-like" look and feel.There is a github project: https://github.com/LuisSala/emberjs-jqm. In my view, if you need very cool animation you can use blossom.If you want to build a app, SC or ember should be OK. I'll choose ember because it 's loosely coupled.
Just say you have a quite large and complicated desktop application written in objective-c/cocoa written properly in MVC. You then wish to replace the V and C so that it is a web application?
Is there anything like Tomcat but for objective c? The closest thing I can think of is somehow convert the Model code into an apache module to load in apache?
Obviously I could embed some sort of HTTP server and write a whole pile of code to manage sessions and requests and responses and so on, but might there be a simpler way?
You can leave the server almost as-is. I'd run it as a daemon in the background.
I'd split the controller part. One part of it resides on the server as a connection between HTTP requests and the daemon.
You could run a self-made http server.
You could build it into a Apache module as you mentioned.
You could access your controller through CGI. This is the easiest option as I see it.
The second part of the controller is written in Javascript in the browser, exchanging data with the server and updating the GUI.
The view part is written completely in javascript.
You could - if you want - leave out the controller on the server and make the model understand HTTP requests.
For the Controller / View part consider using a framework.
jQuery for only a light interface. (Or a similar framework.)
I haven't yet found a framework that leaves all the model stuff to the server. Maybe you can use SproutCore or Cappuccino accordingly.
SproutCore, the full-backed MVC framework that is used by Apple. (Think so at least.)
Cappuccino, another full-backed MVC framework.
Have you looked at Cappuccino? http://cappuccino.org/
I have not used but have heard many good things about it.
There is a new web development platform for Objective-C/Cocoa called Bombax. It sounds like exactly what you're looking for (it is designed to allow you to write entire web applications in Objective-C). Perhaps you could even combine it with Cappuccino. You can check it out at http://www.bombaxtic.com.
The closest you'll probably come to Objective-C web frameworks are either SOPE, or GNUStep, neither of which I have used, but ran across when I was deciding if I wanted to use Rails or something written in Objective-C for my web stuff. There's also ARJDatabase, which is kind of like Core Data, but not source compatible.
The bottom line is, unless you were very careful about how you wrote your code (i.e. wrote it with GNUStep in mind, didn't use anything Apple specific) you're probably going to have to do quite a bit of work anyway. And if you used Core Data at all, there's no way I know of to reuse that outside of a Mac App. And since it's not setup to be used my multiple simultaneous users, you wouldn't want to use that in a web app anyway. Bottom line, I went with Rails.
There is Frothkit - http://code.google.com/p/frothkit/ but it appears not to have been updated for a year.