AS3/Air: PNG > File > FileStream > ByteArray > BitmapData - actionscript-3

I want to use FileSteam.open() to synchronously read image files from disk. I can then get them into a ByteArray with readBytes(), but I can't find how to get that into BitmapData. I know Image can read it as is, but I need BitmapData.
Any suggestions?

in the package flash.display, use Loader::loadBytes ... that'll give you a Bitmap, and the BitmapData can then be simply accessed through Bitmap::bitmapData ... this makes the whole operation asynchronous, of course ... the only thing you could do, is write a decoder yourself ...
now there is a PNG encoder in AS3, in the as3corelib and i guess there are even others, but probably most people considered it pointless to write a decoder, since flash does this in its own, and also encoding is easier than decoding, because decoding means, you have to implement the whole format ... still, you can give it a shot of course ...
well, hope that helps ...
greetz
back2dos

This library on github has a PNGDecoder that works synchronously. Give it a try:
https://github.com/terrynoya/ASImageLib
From the usage wiki:
var bytes:ByteArray = [PNG bytes];
var bmpData:BitmapData = new PNGDecoder().decode(bytes);
this.addChild(new Bitmap(bmpData));
But I'd imagine using the built-in class would be faster, and while it depends on your use-case, typically when dealing with UI like images, asynchronous is preferred to avoid blocking the UI thread (causing the app to stutter). But there could be some use cases.

It have sense, because FileStream works to manage pure data, and BitmapData works for compile or decompile data.
The way Im about to use, is to read the file in the origin and write a temporary file in the application directory, which may be reached by Loader class without troubles.
Wish me luck!

Related

Embedding a file with a variable in AS3 + flixel

I have recently picked up flixel (I have programmed before, but I have not in a while) and I have come across a problem. I am attempting to create maps, and eventually there will be multiple maps available.
I currently have a .txt file that has information that eventually goes into an array. Then I go from array to map with loadmap. It is maybe a simple way to accomplish this task, and maybe their are better ways (I have not explored all the possibilities with flixel, and if there are any opinions, go ahead and let me know) but it works good for now.
As I have previously said, I am trying to do this with multiple maps. I could do this by using [Embed(source = "")] for each .txt file, but this may end up being annoying. So, here is my question: Is there a possible way Embed a file based upon a variable?
My Map class looks like this:
public function Map(MapSet:String, TileSet:String)
{
super(MapSet, TileSet);
//more stuff
}
Now I have tried:
[Embed(scource="data/MapSets/" + MapSet + ".txt", mimeType = "application/octet-stream")]private var loadedMap:Class
and then I use:
map = new Map("Map1x1", "ForestTiles");
add(map);
Is there a possibility of doing this in a different way? Or maybe I am doing something wrong? All opinions are welcome.
It's beneficial to know what code does when using it.
Embed is a meta tag. It tells the compiler to include a certain file into the .swf file.
That means this does not happen at runtime.
When this embed code is "executed", your variables don't even exist yet.
That's why your code cannot work.
Despite not working, your solution is still valid:
If you find it tedious to generate code, write a program that does this for you. Create/use a program that finds all valid files in the given directory and creates all the embed tags. Run this program before the compiler.
To embed a text file and use as a string, try this:
// create source var TextSource
[Embed(source="textFile.txt",mimeType="application/octet-stream")]
private var TextSource:Class;
var myByteArray:ByteArray = new TextSource();
var myString:String = myByteArray.readUTFBytes(myByteArray.length);
// then use for your function
map = new Map("Map1x1", myString);

How can AS3 front-end code and AS2 server-side scripting send objects back and forth, while keeping their methods?

Given the following AS3 front-end code:
m_nc.connect("rtmp://" + pPrimaryIP + "/appname/"+ pVID, pUID, pConfig);
and the following AS2 server-side scripting code:
application.onConnect = function(pClientObj, pUID, pConfig)
{
// do stuff
}
where pConfig is an object of type Configuration, as defined in the AS3 code, having the method:
public function copy(pConfig:Configuration):void
apparently when you try to send the object across while connecting, it loses that method and any other methods. Yet its fields remain basically intact, at least if they're primitives. I can see why this might be so, but is there not some way to keep this loss from happening? I really want to be able to not just send it to the AS2 without losing anything, but to also be able to send it back to the AS3 without losing anything. Is this possible? If so how? Thanks!
You should look at LocalConnection, a class available to both AS2 as AS3 (AS1 even)
clicky

Is there an Actionscript to ABC Bytecode parser?

So, I have an app where users should define ActionScript functions.
What do I need to get the string whritten by the user and convert it to bytecode so that I can use it with as3-commons-bytecode?
Edit
I don't think I was clear enough. I need to turn: if(!myValue) {...}
Into this:
...
findpropstrict private::myValue
getproperty private::myValue
not
iffalse L1
...
Because with this ^^^^ code, I can use as3-commons-bytecode to do what I need.
I took a look at this app's source code. It's very confusing, the project is old and the code is a mess, but it works. I need to find "where the magic happens". Can you show me the way?
You should use part of this project :
eval.hurlant.com/demo/#app=da4a&757d-selectedIndex=0
Check source , there is parser to ABC .
I'm not aware of any libraries that do this for you, but to achieve this functionality you should parse user's input into function names.
For example, you can call a function just by having it's name as a String like so:
var functionName:String = "myMethod";
function myMethod():void
{
trace("myMethod");
}
this[functionName](); //traces "myMethod"
Of course, if you wish to interpret advanced strings with getting/setting objects and their properties and any other user defined statements, that would require to write quite a sophisticated string-to-bytecode converter.
UPDATE:
There's also AS3Eval library that might do the job. Take a look at http://eval.hurlant.com/
There is a library for Haxe which makes it possible to compile Actionscript assembly language into ABC at runtime, but this is still lower-level than the Actionscript you normally write.
http://haxe.org/com/libs/format/abc
The most likely solution is a server or other process which can compile and return SWF content for you. Haxe has a very fast and straightforward compiler, but it may also be possible to use Tamarin or another solution for compiling AS3 on the server.
Actually, there is a runtime library for executing Haxe code, which again, is very similar to Actionscript. Might be worth looking into:
http://code.google.com/p/hscript/
What exactly want to do? To compile "string" the string must be something meanfull for the compiler such as package not a simply string ( like 'asdas ' ). If you don't wont to use flash/flex compiler you may compile AS to ABC with Ant or Haxe. But ther is a problem - how you will start this ABC?

referencing existing sound objects on the timeline via actionscript 3

In Actionscript 3 / Flash 10, is it possible to programmatically reference a sound object that exists on the timeline? I've found lots of examples for referencing DisplayObjects via the following sytax:
var m:MovieClip = stage.getChildByName("SomeMovieClipClass");
var n:MovieClip = stage.getChildByIndex(1);
But this doesn't seem to include sound objects. Similarly, it seems straightforward to instantiate and play a sound that exists in the Library via Actionscript:
var s:SoundClip1 = new SoundClip1(); // exported in first frame via properties
s.play();
For my purposes, though, I'd like to reference sound clips (ideally in a specific layer, although that seems to be a design-time element) that designers have adjusted and arranged on the timeline, so that I can inspect their waveforms via code, at runtime. Something like this:
// Imaginary Code
sc = timeline.getSoundClipByName("SoundClip1");
sc.extract(waveform,sc.length/1000 * bitrate);
Is this possible? Thanks!
As of this date, no it is not possible to access the soundChannel generated by a timeline sound. It's a feature I would love to see implemented.
I was going to try to test the feasibility of using computeSpectrum to get the waveform of a timeline sound but I'm having problems importing mp3s right now. In absence of firsthand proof of concept, I searched around and found this thread:
http://www.kirupa.com/forum/showthread.php?t=329632
Which links to this solution
http://www.mail-archive.com/flashcoders#chattyfig.figleaf.com/msg43157.html
But of course this doesn't allow you to disambiguate between different timeline sounds. I'm pretty sure you won't be able to do that at all.
I have not ever used Sound.extract(), but if the sounds exist in the fla library this indicates to me that you can simply give them a Class name and at runtime use extract() to gather the waveform for your own purposes, yes? Then whenever the appropriate timeline sound plays, you can tap into the waveform from the Sound object. Perhaps a timeline callback or event would suffice for this?

Asynchronous loading / error handling

Let's say that I have a bunch of objects (thumbnails in a matrix for example) and I need to load some data files for all of those over the network (HTTP). So each thumbnail has the thumbnail image itself and an xml file for instance.
There's a number of things that can go wrong from IO errors to bad URLs to badly formatted XML and so on. The question is what is the best / most elegant / most robust way of organizing all of this. What I usually end up doing is having a load manager that tells the
child objects to start loading and then monitors the loading. The child objects have listeners for IO errors and HTTP status events. When all children have loaded everything (with some possible failures) something is done (the thumbnails are shown or whatever).
I was thinking that there has to be a better way of doing this, something that would allow me to maybe use throw clauses when errors occur. Throwing something from the listener isn't going to do much good of course. So what to do. Have a local flag(s) in the child objects and abort if something fails or what?
I am using AS3 but the question should be pretty much the same for other languages, at least for object oriented ones.
Just to be clear I'm not looking for any program code, just general ideas on a design pattern. I also realise that because of the asynchronous load I'm tied in to event handling at least in the child objects.
i use a "queue" package which is able to deal with all sorts of asyncronous operations. the nice thing is you can nest these operations (composite pattern) and create quite complex stuff easily. if events occur you can catch them either at the root as they "bubble up the queue tree) or directly where they originate, depending on the listeners you add.
interface Qable extends IEventDispatcher {
function start()
function stop()
}
interface Q extends Qable {
function add(item:Qable):Q
function remove(item:Qable):Q
...
}
var q1: Q = new Q
q1.add(new Qable(...))
q1.add(new Qable(...))
var q : Q = new Q
q.addEventListener(Event.COMPLETE, onComplete)
q.addEventListener(Event.ERROR, onError)
q.add(new Qable(...))
q.add(new Qable(...)).addEventListener(Event.Error, onItemXError)
q.add(m1)
q.start()