Level Master 2000: screenshot0001

Today I prepared the initial launch of Level Master 2000 at google code: http://code.google.com/p/levelmaster2000/. There are still a lot of features missing, as the project page states:

August 24th, 2010. Commited as is. Consider this more a preview/announcement rather than a real release. A major restructuring will occur within the next months, but anyway – here it is!

Nevertheless, it’s a good feeling finally having it on air and getting some feedback!

1. Clean all targets
2. Regenerate the qMake file via Qt Creator
3. Rebuild the project
4. Install the latest Flashplayer and add the app/AS3/bin directory to Flash Player’s local trusted

That was it! See for yourself:

Level Master 2000: running on OS X

The GUI needs a bit work though (e.g. the “delete entity” button), but all in all I’m really impressed how easy this was.

-static-link-runtime-shared-libraries=true

to the additional compiler options. Doing some more in depth research, I discovered that this isn’t neccessary with a newer version of FlashDevelop – and I can confirm: it’s true =)
After the update procedure, everything compiled fine in debug mode. In release mode, it compiled too, but I got a runtime error: “VerifyError: Error #1024: Stack underflow occurred”. Again, investigating this error on the web, I stumbled over http://bugs.adobe.com/jira/browse/ASC-2266. The piece of code causing this, looked like so:

conn = new LocalConnection();
conn.client = this;
conn.allowDomain('*');
try {
	conn.connect("_SchemaConnection");
} catch (error:ArgumentError) {
	trace("Can't connect to _SchemaConnection");
}

So as you can see, it’s not the same as in the link above. I started commenting out line by line, and then I discovered, that it was the trace call. Replacing it with a Logger call finally fixed the error:

Logger.print(this, "Can't connect to _SchemaConnection");

I guess we’ll just put that on the unsolved mysteries stack

<Language name="xml"  ext="pbelevel"></Language>

And tada – you’re off to go!

In short, using this component, you can combine, what normally is hard to achieve with Flash: animation with “thousands of buildings on the screen at once“.

SchemaGenerator.instance.generateSchema();

“dumps all classes and public info to a xml file”.
We’ll, I’ve used it now, and I must admit that was a lie
So here’s how you use it, and what it results in!

First, you need to establish a local connection, and then call generateSchema:

conn = new LocalConnection();
conn.client = this;
conn.allowDomain('*');
try {
	conn.connect("_SchemaConnection");
} catch (error:ArgumentError) {
	trace("Can't connect to _SchemaConnection");
}
 
SchemaGenerator.instance.generateSchema();

SchemaGenerator.instance.generateSchema will then call OnSchemaReceived in your class, so you need to add that. It takes two string arguments: type and data. Type is either “START”, “END”, “ERROR” or “TYPE”. Data is an XML description of the current processed class (internally it uses flash.utils.describeType), which you then can further interact with.
Here’s an example of how OnSchemaReceived could look like:

public function OnSchemaReceived(type:String, data:String):void
{
	switch( type )
	{
		case "START":
		break;
 
		case "END":
		break;
 
		case "ERROR":
		break;
 
		case "TYPE":
		{
			var myXML:XML = new XML(data);
			myXML.ignoreWhite = true;
 
			var xmlList:XMLList = myXML.child("factory");
 
			//Check accessors:
			for each (var acc:XML in xmlList.accessor)
			{
				//DO SOMETHING.
			}
 
			//Check public variables:
			for each (var pVar:XML in xmlList.variable)
			{
				//DO SOMETHING.
			}
		}
		break;
	}
}

That should help you getting started!

• In Flash, we use ExternalInterface to communicate with the outside world (meaning Javascript)
• In Qt, we run a Webview, which loads the SWF and catches the ExternalInterface calls.
• These caught calls are then passed on to Qt

So in short, it’s like: Flash >> Javascript >> Qt and the otherway.
We’ll see how this decision turns out in the end, but it’s an interesting approach indeed (and in case of emergency, there are ways to improve performance)!

For now, I can say, that I got the basic communication working:


It features:

• Entity selection
• Display the as “editable” marked properties of the selected entity, grouped by components
• (W.I.P.)Modify the properties: numbers and strings working, custom data types (like a point) on the way

Next upcoming features:

• Entity Browser: visualisation
• Entity Browser: interaction (selecting entities, adding + deleting components)

Stay tuned!

• Use a current version of PushButton Engine.
• A properly initialized scene (see PBE Series: initializing your scene via ActionScript on how to setup it up)

Today I will show you, how to create a component for PushButton Engine, that registers, if an entity got clicked on or not.

In general, you got two possibilities how to handle this:

1. per object level
2. on a global level

Per object level: since it’s flash, you can simply add an event listener to your graphics component, which listens to click events.

I personally don’t like that too much though, so let’s consider variant two: global level.

It’s a component which exists once in the scene, and not per entity. It listens to click events which happen on the main stage, and on each click, it uses the built in functions PBE.scene.getRenderersUnderPoint and/or PBE.spatialManager.getObjectsUnderPoint to determine, which objects got clicked on.

This version only uses the getRenderersUnderPoint, the main stuff is going on in the OnClick method:

package
{
   import com.pblabs.engine.PBE;
   import com.pblabs.engine.debug.Logger;
   import com.pblabs.engine.entity.EntityComponent;
   import com.pblabs.rendering2D.DisplayObjectRenderer;
 
   import flash.events.MouseEvent;
   import flash.geom.Point;
 
	public class ClickComponent extends EntityComponent
	{
		protected override function onAdd():void
		{
			PBE.mainStage.addEventListener(MouseEvent.CLICK, OnClick );
		}
 
		private function OnClick(e:MouseEvent):void
		{
			var results:Array = new Array();
			var point:Point = new Point( PBE.mainStage.mouseX, PBE.mainStage.mouseY );
			var foundRenderers:Boolean = PBE.scene.getRenderersUnderPoint( point, results );
 
			for each( var obj:DisplayObjectRenderer in  results )
			{
				Logger.print( this, obj.name );
			}
		}	  
 
		protected override function onRemove():void
		{
			PBE.mainStage.removeEventListener(MouseEvent.CLICK, OnClick );
		}
	}
}

Now if you want to get the spatial objects, simply use this:

var spatials:Array = new Array();
PBE.spatialManager.getObjectsUnderPoint( PBE.scene.transformScreenToWorld(point), spatials, new ObjectType("Renderable"));
 
for each( var spatialObj:ISpatialObject2D in spatials )
{
	Logger.print( this, spatialObj.position.toString() );
}

The main difference is that getRenderersUnderPoint results in DisplayObjectRenderers, and getObjectsUnderPoint results in ISpatialObject2Ds.

Also, see that you can supply an object mask. Leaving it null will take all objects into consideration.

All in all you can see, how easy this is (for such a complex sounding task)!

//Produces an XML object that describes the ActionScript
//object named as the parameter of the method:
var varList:XML = flash.utils.describeType( /*INSERT OBJECT OR CLASS*/ );

And then, depending on what you want to access (properties, members or functions), just iterate over your XML and you’re good!

Logger.print(this, "Properties:");
for each (var a:XML in varList.accessor)
{
	Logger.print(this, a.@name+" : "+a.@type);
}

Logger.print(this, "Variables:");
for each (var b:XML in varList.variable)
{
	Logger.print(this, b.@name+" : "+b.@type);
}

Logger.print(this, "Methods:");
for each (var c:XML in varList.method)
{
	Logger.print(this, c.@name+" : "+c.@type);
}

For me with my editor, I’ll probably do this once at startup and keep the information for all the components stored somewhere. I currently don’t know how performance is, but I guess it’s gonna be better that way. If it turns out to be a wrong approach, I’ll post my conclusion here

Edit – doing it the PushButton way:
Of course there seems to be a much easier way doing it with PushButton Engine. I must admit, I haven’t tried it, but it seems there’s this built in function which sort of dumps all classes and public info to a xml file by just using:

SchemaGenerator.instance.generateSchema();

Nice!