[Help][AS3] Total newb to as3 requests help.

Hello, this looks like a great community and in time I hope to be able to contribute as many answers as I have questions, but for now, I'm in much needed help on getting started with online game development using AS3.

Quick background: I'm not new to game coding so I won't bore you with the basics, but I am in need of some basic hand holding to get me up and running and once the basics are covered, I should be able to come to grips fairly quickly.

Short term goals: Setting up a basic framework so I can get some ideas up and running, explore the feature set, performance test, etc.

Long Term Goals: To write simple to advanced 2D games.

Here's my first set of questions, thank you in advance for those who take the time to reply. ;)

1) I'd like to develop in the best IDE available for AS3 game development. I don't mind if it's free or commercial. Which IDE do you suggest? And can you please provide exact links to the info page?

2) I'd like to purchase 2 books on the subject. One being something for total noobs to as3 and the other for the more advanced as3 coder. Which 2 books would you suggest?

3) Can anyone point me to a complete demo project which does nothing more than bounce around the screen a bunch of (bitmapped) sprites? This is always a good demo to view when starting a new language. ;)

4) I'm use to this style of 2d coding: I have a large texture where I place a number of different "sprites". Since I know where inside the texture these sprites are, I can then render to the screen any of these sprites. Every frame in my game loop goes something like this:

Clear the off screen canvas.
Draw my background on the canvas.
Draw all of my sprites to the canvas.
Draw the canvas to the main screen.

With DirectX this is basically called "page flipping" or "double buffered graphics".

Will I be able to have similar techniques using AS3? If so, could you elaborate a bit on the process? (Feel free to link to existing source demos if available.)

5) Thanks to modern 3D gpu's I'm used to my 2d sprites having the ability to rotate, scale, support alpha blending, additive blending, etc. Do we have this capability in AS3? If so, could you elaborate a bit on the process?

I know sometimes these noobish questions can be an eyesore for the regulars, but I greatly appreciate any help. ;)

Sorry, im not an AS3 programmer, but I can answer question 5 for you:
Yes, every movieClip [although yur are going to use mainly bitmaps/sprites when using AS3] has a scale and rotation value. For example, say I have a movieclip with the instance name of "hero":
The code for rotating it 10 degrees clockwise would be:

PHP Code:

---

hero._rotation += 10; 


---

For scale, every movieclip has an _xscale and _yscale variable. To scale our hero down to half size, we would say:

PHP Code:

---

hero._xscale = 50;
hero._yscale = 50; 


---

The _xscale and _yscale values are by default 100.

Im not quiet sure what you mean with alpha blending & additive blending. Maybe clarify? And if you mean the alpha value (transparency) of a movieclip, then you could do something liek this:

Lets say we want to make our hero movieclip half-transparent:

PHP Code:

---

hero._alpha = 50; 


---

Easy as that! The _alpha value of a movieclip is be default 100.

Hope this is of some use to you.
:)

1. Basically you have 2 options:
use Flash IDE (CS3 or CS4) - 700$ if bought from Adobe
or use FlashDevelop with Flex SDK - free but its basically just code editor and contains no vector drawing or animation tools. Seeing as you want to use bitmap sprites anyway this may be not such drawback.

2. I dont have any AS3 books myself but I have heard good things about Keith Peters book "Foundation Actionscript 3.0 Animation: Making Things Move!"

3. Maybe you could look at some of the AS3 game tutorials at 8bitrocket
http://www.8bitrocket.com/blog.aspx?BCATID=206
Blitting is covered there, they contain code examples and explanations.

4. Yes, you can do exactly same with AS3. Look for keywords bitmapData and copyPixels.

5. Every display object in AS3 has rotation, scale and alpha property. But please notice the code pseudobot posted is for AS1. In AS3 scaling and alpha are between 0 and 1, and names of properties were changed:
http://livedocs.adobe.com/flash/9.0/...layObject.html

Just to add to a thread that's already been covered.

1) Or Flex. So many people are under the impression that Flex means using mxml and nothing more.
Flex runs on Eclipse and fully supports as3 ( I've never actually used either the design mode or written a line of mxml ) and comes with a really powerful profiler ( Although I think that may be the more expensive again "pro" version ).

Think of Flex as the expensive big brother of the Flash Develop option, just using Eclipse instead.

2) Colin Moock, "Essential Actionscript 3.0", it's the bible.

3) 8BitRocket is the unofficial home of Flash blitting tuts on the net.
http://blog.gamingyourway.com/PermaL...01e0b123b.aspx
That's the source for a previous 48hour comp. entry on here. It's a basic framework with a singleton / object pooling etc. A nice starting point to work from ( I used sprites rather than blitting, but replacing that isn't that big a deal. I thought I'd link 'cause with as3 there's a lot of little examples but very few "Here's a whole game with it's structure in place" examples ).

4) Yep, although you don't really need to double buffer that often, as Flash does internally and there's no vsync, so you're still going to get the rip and tearing. It's only really useful for when the game will take a long time to plot a screen, eg the voxel landscape link in my sig, I used double buffering for that.

5) See last post :)

Squize.

Good stuff! Thanks everyone for replying! This is enough to get me started. I will post here again after I have an ide and have dived into some initial code! :)

hmm... still in the research phase. :( I was really hoping there was a simple solution provided by the AS3 pipeline that allowed easy flexable 2D sprite blitting. But so far I havn't found anything. Everything I've found requires pre-rendering the frames for rotation, scaling, etc. I havn't had to pre-render sprite frames since my Atari ST days. lol. Perhaps I am missing something?

In a nutshell I want my sprites to have the ability to rotate,scale,alpha support, etc, in real time. Is this even possible in AS3? Thanks for any help on the subject. ;)

Not if you're blitting no.

With you being an old ST boy you know that blitting in Flash is a misnomer, it's just using low level bitmap commands to plot images. There's no actual blitter equivalent on which to perform transformations of the data before outputting it to the screen.

You either have to pre-render rotations in your sprite sheet, or get Flash to rotate them at runtime ( And then store those rotated images in a sprite sheet ).

Here's a couple more links which may help:
http://www.photonstorm.com/topics/as3/libs/pixelblitz
http://www.gamepoetry.com/blog/2008/...zed-rendering/

Flash wasn't built to do cool stuff, it was built for RIA and streaming video players, so trying to get cool stuff out of it isn't as easy as it should be.

If you can cope with your game not running at the max possible speed, the sprite and movieclip primitives give you everything you want and in the grand scheme of things don't cause a huge hit, it's only when you're looking at a lot of them it'll bite you.

Squize.

Just to add to Squize...

If you use bitmap object then it has direct rotation, scaling etc properties like all display objects. You can add it directly to the stage and control it directly. This is how Flash games have been done since F4.

However, why all this blitting talk has came up is because using separate objects on stage has been proven to slow down Flash Player. The fastest method to have many objects without losing speed is to use one main bitmap on stage and put all objects there at each step with copypixel or similar bitmapdata method. But because this method bypasses the transformations (and why its probably faster) you lose the rotation, scaling and such.

Flash has no access to gpu so speed can be important issue. Too many moving objects can easily slow down your game to half its original speed. How many objects is too many and how much slowdown can you accept? I suggest you try out both ways and decide by your own tests.

Quote:

---

Originally Posted by Squize

...If you can cope with your game not running at the max possible speed, the sprite and movieclip primitives give you everything you want and in the grand scheme of things don't cause a huge hit, it's only when you're looking at a lot of them it'll bite you.

Squize.

---

Thanks Squize and Tonypa, very good info. I think at least for my initial AS3 experiements I'd like to mess around with the sprite primitive. I feel stooopid because for some reason I'm not grasping (or finding very basic examples of) the basics of all basics, just bouncing a few sprites around the screen. Do you (or anyone) know of any complete AS3 source examples (for Flash Develop) that simply displays a few sprites bouncing around the screen using the sprite primitive? Thanks.

Something like this?
http://www.actionscript.org/resource...t-3/Page1.html

well..I think it's fair to say I'm the stoopidest sob on this site. I still don't have a foundation I can build on. Here's what I want to do..

Using bitmapData,copyPixels I want to be able to blit sprites on the screen from my image.png which holds all of the sprite images. I think I should be able to do this using a function like this:

function DrawImage( image:BitmapData , x:Number , y:Number , sx:int , sy:int , w:int , h:int ):void
{
point = new Point(x,y);
rect = new Rectangle(sx,sy,w,h);
backBufferData.copyPixels( image , rect , point )//, null , null , false);
}

I've given up on researching the sprite primative because it's too slow and the game I eventually want to code will need to have quite a few sprites moving around.

What should I use? FlashDevelop seems great but I can't find any source examples I can just load up, build, see it run and start playing with. I've downloaded a few Flex examples, they don't work with FlashDevelop.

Maybe I'm just having **** luck, but there does not appear to be a generic example of moving sprites around using the fast copypixels method, in a FlashDevelop compatible format. Do I need to use another more popular IDE?

In a final plea of help, I have attached 2 files:

sprites.png - currently just holds 2 sprites. Each sprite is 32x32. The first sprite is at 0,0 the 2nd sprite is at 34,0.

background.jpg - Nothing more than a 512x512 background.

If someone could take the time to write an AS3 program which simply moves some sprites over the background in pong fashion that would be awesome. Ideally, it would be even greater if the code had separate logic(),render() functions to make it easier to play around with. Perhaps start out with 10 sprites, and then when a key is pressed add another 10, etc, etc.

Also, I've seen some code that uses arrays and some that use linked lists. I'd prefer to use linked lists because that's what I'm using now in Blitzmax. It's very dynamic and easy to add new sprites at anytime.

Again..trust me...I've been there...seeing a noob ask for a walk through in code like this sucks. Why can't I get this going on my own? I don't know. I get all these errors when I'm trying to compile/build, nothing works, syntax errors, etc, etc. But anyway, I'm SURE once I see this working on my end I'll be able to FLY on my own full speed ahead! So if anyone takes on this little project, I will be forever gratefull!!

I'm really hoping copypixel also copies over the alpha values in the png as well! I can live with having to pre-scale, pre-rotate everything in my sprite strips, but if I lose alpha blending as well in copyPixels() yikes... I'm back in the stone age then! :) lol..

Anyway...I'm using FlashDevelop, so I'm hoping the example works in that as well. Again...if I need to use Flex Builder instead let me know. Thanks again to anyone helping this stupid sob. :)

Your post starts really well, then goes on to separate logic / render classes and then linked lists ? Mate, unless someone has got something pre-written that does all that then you can only really expect something which can be hacked out in Flash in a couple of minutes. Any more than that and basically you've got a stalker helping you.

Sprites really aren't that bad, and they'd save a lot of this initial pain whilst you find your way around as3. If speed is the most important thing, then attaching a bitmap seems to be quicker than blitting, as shown in that link to the gamepoetry site from my earlier post.

What parts of Flex projects aren't working in Flash Develop ? As far as I was aware FD uses the same compiler as Flex ?

What part of your DrawImage method doesn't work ? It seems perfectly fine. Is the bitmap canvas not attached to the display list correctly ? You linking to the embedded tilesheet correctly ?

"I can't find any source examples I can just load up, build, see it run and start playing with"

There is a real shortage of code which just runs out of the box, anything more complex than a simple class and you'll really be struggling to find anything.
It's just the way it is in as3 I'm afraid. A lot of people say how great it is, but very few people even now are willing to show complete code which would be helpful to total beginners of the language.
The source I linked to of my own game I think takes some messing around to get working for most people, and I've tried to make that as simple as possible. Classpaths, Flex / FD / Flash, everything makes swapping code just that bit harder than it ever used to be.

"I'm really hoping copypixel also copies over the alpha values in the png as well!"

There is a flag in the copyPixel method for doing that.

Tell us some of the errors you're getting, show some of the code you've got, share what traces out when you pass values to your DrawImage method.
Honestly it'll be a lot quicker for you to show exactly what's wrong rather than waiting for someone to write code for you.

Squize.

I hear ya Squize. Thanks. I'm juggling a multitude of things right now so it's hard to sit still for a long time and do code exploration. Ok... I'll start posting what I've got and perhaps you can chime in if you can, and tell me where I'm going wrong. That sounds fair enough. ;)

Still having massive problems. Amazing how there is really no simple generic sprite example on the net somewhere. Oh well...that's one of the first things I'll be sharing here in this thread after I'm done. :) It may take me days, weeks, to get it done, but it will be done! :) lol..

I'm using FlashDevelop and getting massive errors everywhere, but that's ok. I'm just building some generic code with place holders and will fill in the blanks as I progress.

Things I'm still stuck on:

a) How to properly embed a graphic and be able to use it in the Blit() function.

b) How to create list of objects so I can iterate through a list and update/render each object.

Ok...will post later after another lengthy research session. :)

Code:

---

package
{
        import flash.display.*;
        import flash.events.*;
        import flash.utils.*;
        import flash.geom.*;
        import flash.events.*;       
        //
        // Set up default resolution and frame rate
        //
        [SWF(width = "640", height = "480", frameRate = "30")]
        //
        //
        //
        public class Main extends MovieClip
        {
                //
                // Embed graphic data
                //
                [Embed(source = "background.jpg")]
                    [Embed(source = "sprites.png")]
                //
                // Vars
                //
                var backBufferData:BitmapData; //backbuffer bitmap data to draw on
                var backBuffer:Bitmap; //the bitmap object
                var point:Point;
                var rect:Rectangle;
                //
                //
                //
                public function Main()
                {
                        backBufferData = new BitmapData(640,480 , false , 0x666666); //data storage of the backbuffer
                        backBuffer = new Bitmap(backBufferData); // "canvas" of the backbuffer
                        addChild(backBuffer); //add the backBuffer canvas object to the displaylist of the stage                       
                        addEventListener(Event.ENTER_FRAME, Mainloop);
                }
                //----------------------------------------------------------------------------
                // mainloop
                //----------------------------------------------------------------------------
                public function Mainloop(e:Event)
                {
                        Update();
                        Render();
                }
               
                //----------------------------------------------------------------------------       
                // update objects
                //----------------------------------------------------------------------------
                function Update():void
                {
                //
                // Update all game objects here
                //
                }
                //----------------------------------------------------------------------------
                // render objects
                //----------------------------------------------------------------------------
                function Render():void
                {
                        backBufferData.lock();
                        //
                        // Render all objects here
                        //
                        backBufferData.unlock();
                }
                //----------------------------------------------------------------------------
                // Blit Function
                //----------------------------------------------------------------------------
                function Blit(image:BitmapData , x:Number , y:Number , sx:int , sy:int , w:int , h:int ):void
                {
                        point = new Point(x,y);
                        rect = new Rectangle(sx,sy,w,h);
                        backBufferData.copyPixels(image , rect , point )//, null , null , true);
                }

        }
}

---

Solved the embed problem I think, at this point the code looks like it should at least be blitting the background image. I don't have any code to blit sprites yet. Just wanting to blit the background. Here's the code:

Code:

---

package
{
        import flash.display.*;
        import flash.events.*;
        import flash.utils.*;
        import flash.geom.*;
        import flash.events.*;       
        //
        // Set up default resolution and frame rate
        //
        [SWF(width = "512", height = "512", frameRate = "30")]
        //
        //
        //
        public class Main extends MovieClip
        {
                //
                // Embed graphic data
                //
                    [Embed(source = "background.jpg")]
                    private var BackgroundImg:Class;
                    [Embed(source = "sprites.png")]
                    private var SpriteImg:Class;
                //
                // Vars
                //
                var back1:BitmapData = new BackgroundImg;
                //
                var backBufferData:BitmapData; //backbuffer bitmap data to draw on
                var backBuffer:Bitmap; //the bitmap object
                var point:Point;
                var rect:Rectangle;
                //
                //
                //
                public function Main()
                {
                        backBufferData = new BitmapData(512,512 , false , 0x666666); //data storage of the backbuffer
                        backBuffer = new Bitmap(backBufferData); // "canvas" of the backbuffer
                        addChild(backBuffer); //add the backBuffer canvas object to the displaylist of the stage                       
                        addEventListener(Event.ENTER_FRAME, Mainloop);
                }
                //----------------------------------------------------------------------------
                // mainloop
                //----------------------------------------------------------------------------
                public function Mainloop(e:Event)
                {
                        Update();
                        Render();
                }
               
                //----------------------------------------------------------------------------       
                // update objects
                //----------------------------------------------------------------------------
                function Update():void
                {
                //
                // Update all game objects here
                //
                }
                //----------------------------------------------------------------------------
                // render objects
                //----------------------------------------------------------------------------
                function Render():void
                {
                        backBufferData.lock();
                        //
                        // Render all objects here
                        Blit(back1,0,0,0,0,512,512)
                        //
                        backBufferData.unlock();
                }
                //----------------------------------------------------------------------------
                // Blit Function
                //----------------------------------------------------------------------------
                function Blit(image:BitmapData , x:Number , y:Number , sx:int , sy:int , w:int , h:int ):void
                {
                        point = new Point(x,y);
                        rect = new Rectangle(sx,sy,w,h);
                        backBufferData.copyPixels(image , rect , point )//, null , null , true);
                }

        }
}

---

And here's all the errors I get when I "test movie" from FlashDevelop:

Code:

---

C:\FlashProjects\Test1\src\Main.as(27): col: 7 Warning: var 'back1' will be scoped to the default namespace: Main: internal.  It will not be visible outside of this package.
var back1:BitmapData = new BackgroundImg;
^
C:\FlashProjects\Test1\src\Main.as(29): col: 7 Warning: var 'backBufferData' will be scoped to the default namespace: Main: internal.  It will not be visible outside of this package.
var backBufferData:BitmapData; //backbuffer bitmap data to draw on
^
C:\FlashProjects\Test1\src\Main.as(30): col: 7 Warning: var 'backBuffer' will be scoped to the default namespace: Main: internal.  It will not be visible outside of this package.
var backBuffer:Bitmap; //the bitmap object
^
C:\FlashProjects\Test1\src\Main.as(31): col: 7 Warning: var 'point' will be scoped to the default namespace: Main: internal.  It will not be visible outside of this package.
var point:Point;
^
C:\FlashProjects\Test1\src\Main.as(32): col: 7 Warning: var 'rect' will be scoped to the default namespace: Main: internal.  It will not be visible outside of this package.
var rect:Rectangle;
^
C:\FlashProjects\Test1\src\Main.as(47): col: 1 Warning: return value for function 'Mainloop' has no type declaration.
{
^
C:\FlashProjects\Test1\src\Main.as(55): col: 12 Warning: function 'Update' will be scoped to the default namespace: Main: internal.  It will not be visible outside of this package.
function Update():void
^
C:\FlashProjects\Test1\src\Main.as(64): col: 12 Warning: function 'Render' will be scoped to the default namespace: Main: internal.  It will not be visible outside of this package.
function Render():void
^
C:\FlashProjects\Test1\src\Main.as(76): col: 12 Warning: function 'Blit' will be scoped to the default namespace: Main: internal.  It will not be visible outside of this package.
function Blit(image:BitmapData , x:Number , y:Number , sx:int , sy:int , w:int , h:int ):void
^
Build halted with errors (fcsh).
Done (1)

---

Really don't have a clue what the errors are trying to tell me. I think I'm getting so close though! :)

Ok..I'm able to build this code with no errors:

Code:

---

package
{
        import flash.display.*;
        import flash.events.*;
        import flash.utils.*;
        import flash.geom.*;
        import flash.events.*;
        //
        // Set up default resolution and frame rate
        //
        [SWF(width = "512", height = "512", frameRate = "30")]
        //
        //
        //
        public class Main extends MovieClip
        {
                //
                // Embed graphic data
                //
                [Embed(source = "background.jpg")]
                private var BackgroundImg:Class;
            [Embed(source = "sprites.png")]
                private var SpriteImg:Class;
                //
                // Vars
                //
                public var back1:BitmapData = new BackgroundImg;
                //
                public var backBufferData:BitmapData; //backbuffer bitmap data to draw on
                public var backBuffer:Bitmap; //the bitmap object
                public var point:Point;
                public var rect:Rectangle;
                //
                //
                //
                public function Main()
                {
                        backBufferData = new BitmapData(512,512 , false , 0x666666); //data storage of the backbuffer
                        backBuffer = new Bitmap(backBufferData); // "canvas" of the backbuffer
                        addChild(backBuffer); //add the backBuffer canvas object to the displaylist of the stage                       
                        addEventListener(Event.ENTER_FRAME, Mainloop);
                }
                //----------------------------------------------------------------------------
                // mainloop
                //----------------------------------------------------------------------------
                public function Mainloop(e:Event):void
                {
                        Update();
                        Render();
                }
               
                //----------------------------------------------------------------------------       
                // update objects
                //----------------------------------------------------------------------------
                public function Update():void
                {
                //
                // Update all game objects here
                //
                }
                //----------------------------------------------------------------------------
                // render objects
                //----------------------------------------------------------------------------
                public function Render():void
                {
                        backBufferData.lock();
                        //
                        // Render all objects here
                        Blit(back1,0,0,0,0,512,512)
                        //
                        backBufferData.unlock();
                }
                //----------------------------------------------------------------------------
                // Blit Function
                //----------------------------------------------------------------------------
                public function Blit(image:BitmapData , x:Number , y:Number , sx:int , sy:int , w:int , h:int ):void
                {
                        point = new Point(x,y);
                        rect = new Rectangle(sx,sy,w,h);
                        backBufferData.copyPixels(image , rect , point )//, null , null , true);
                }

        }
}

---

But nothing happens when I click on "Project>Test Movie" I get a line after the build process and it says "No application is associated with the specified file for this operation".

Still...getting much closer me thinks. :)

ok.. I think the problem is I don't have anything associated with "swf" files on my system. In any event, when I click on the generated html files I see that the swf is loaded but nothing is being displayed. Just a while blank page. Here is the final code I'm currently working with:

(I set the SWF properties, res, framerate in the FlashDevelop project properties window.)

Code:

---

package
{
        import flash.display.*;
        import flash.events.*;
        import flash.utils.*;
        import flash.geom.*;
        import flash.events.*;
        //
        //
        //
        public class Main extends MovieClip
        {
                //
                // Embed graphic data
                //
                [Embed(source = "background.jpg")]
                private var BackgroundImg:Class;
            [Embed(source = "sprites.png")]
                private var SpriteImg:Class;
                //
                // Vars
                //
                public var back1:BitmapData = new BackgroundImg;
                //
                public var backBufferData:BitmapData; //backbuffer bitmap data to draw on
                public var backBuffer:Bitmap; //the bitmap object
                public var point:Point;
                public var rect:Rectangle;
                //
                //
                //
                public function Main()
                {
                        backBufferData = new BitmapData(512,512 , false , 0x666666); //data storage of the backbuffer
                        backBuffer = new Bitmap(backBufferData); // "canvas" of the backbuffer
                        addChild(backBuffer); //add the backBuffer canvas object to the displaylist of the stage                       
                        addEventListener(Event.ENTER_FRAME, Mainloop);
                }
                //----------------------------------------------------------------------------
                // mainloop
                //----------------------------------------------------------------------------
                public function Mainloop(e:Event):void
                {
                        Update();
                        Render();
                }
               
                //----------------------------------------------------------------------------       
                // update objects
                //----------------------------------------------------------------------------
                public function Update():void
                {
                //
                // Update all game objects here
                //
                }
                //----------------------------------------------------------------------------
                // render objects
                //----------------------------------------------------------------------------
                public function Render():void
                {
                        backBufferData.lock();
                        //
                        // Render all objects here
                        Blit(back1,0,0,0,0,512,512)
                        //
                        backBufferData.unlock();
                }
                //----------------------------------------------------------------------------
                // Blit Function
                //----------------------------------------------------------------------------
                public function Blit(image:BitmapData , x:Number , y:Number , sx:int , sy:int , w:int , h:int ):void
                {
                        point = new Point(x,y);
                        rect = new Rectangle(sx,sy,w,h);
                        backBufferData.copyPixels(image , rect , point )//, null , null , true);
                }

        }
}

---

I changed a few things, perhaps I'm just reaching, but anyway I'm able to run it in the FlashDevelop window and now it says:

"TypeError: Error #1034: Type Coercion failed: cannot convert Main_BackgroundImg@e982629 to flash.display.BitmapData.
at Main()"

It's really quite funny...after I get this #$%^&* thing to render the background, it's all down hill from there. :)

Code:

---

package
{
        import flash.display.*;
        import flash.events.*;
        import flash.utils.*;
        import flash.geom.*;
        import flash.events.*;
        //
        //
        //
        public class Main extends MovieClip
        {
                //
                // Embed graphic data
                //
                [Embed(source = "background.jpg")]
                private var BackgroundImg:Class;
            [Embed(source = "sprites.png")]
                private var SpriteImg:Class;
                //
                // Vars
                //
                private var mybackground:BitmapData = new BackgroundImg;
                //
                private var backBufferData:BitmapData; //backbuffer bitmap data to draw on
                private var backBuffer:Bitmap; //the bitmap object
                private var point:Point;
                private var rect:Rectangle;
                //
                //
                //
                public function Main()
                {
                        backBufferData = new BitmapData(512,512 , false , 0x666666); //data storage of the backbuffer
                        backBuffer = new Bitmap(backBufferData); // "canvas" of the backbuffer
                        addChild(backBuffer); //add the backBuffer canvas object to the displaylist of the stage                       
                        addEventListener(Event.ENTER_FRAME, Mainloop);
                }
                //----------------------------------------------------------------------------
                // mainloop
                //----------------------------------------------------------------------------
                private function Mainloop(e:Event):void
                {
                        Update();
                        Render();
                }
               
                //----------------------------------------------------------------------------       
                // update objects
                //----------------------------------------------------------------------------
                private function Update():void
                {
                //
                // Update all game objects here
                //
                }
                //----------------------------------------------------------------------------
                // render objects
                //----------------------------------------------------------------------------
                private function Render():void
                {
                        backBufferData.lock();
                        //
                        // Render all objects here
                        Blit(mybackground,0,0,0,0,512,512)
                        //
                        backBufferData.unlock();
                }
                //----------------------------------------------------------------------------
                // Blit Function
                //----------------------------------------------------------------------------
                private function Blit(image:BitmapData , x:Number , y:Number , sx:int , sy:int , w:int , h:int ):void
                {
                        point = new Point(x,y);
                        rect = new Rectangle(sx,sy,w,h);
                        backBufferData.copyPixels(image , rect , point ,null , null , true);
                }

        }
}

---

Nice blog you've got going here mate ;)

One thing that I noticed was,

private var mybackground:BitmapData = new BackgroundImg;

should be:

private var mybackground:BitmapData = new BackgroundImg();

( You're making a new instance of your BackgroundImg class ).

I know you're going to be happy just to get it to publish without errors, but aren't you adding the background to the stage, and then just blitting that background on top of it in your enterFrame ?
Perhaps comment out your call to the render method until you see something in the swf, just so it's one less thing which could be playing up, and if you're copying the background over the background you're not missing anything even if it works.

Squize.

I'm pretty sure that when linking an image asset to a variable it becomes a "Bitmap" object. To get the bitmapData:

Code:

---

[Embed(source = "background.jpg")] private var BackgroundImg:Class;

private var mybackground:BitmapData = new BackgroundImg().bitmapData;

---

like Squize said, you need to instantiate the Class using the brackets. That would explain this error:

"TypeError: Error #1034: Type Coercion failed: cannot convert Main_BackgroundImg@e982629 to flash.display.BitmapData.
at Main()"

FlashDevelop is just an IDE, whats spitting out those errors is the FlexCompiler, part of the FlexSDK.

by the way, FDT forever! get some ANT compiling into ya