[Solved] Adding child to an existing element to inherits it’s lights

Troubleshooting General Help
1

Hi,



I use an imported model via OgreXML as battleground for my game.

Once the battleground is loaded ( and updated ), I add some characters on it.

My characters are also imported via OgreXML but they don’t have their own lights.



For now, I add a simple sunlight to my rootNode to see my characters.



My problem is as follow : I want the characters to inherits the lights from the battleground.





I use this method in the actual system to add my characters :



[java]

private void addSceneCharacterToTeam( SceneCharacter sceneChar, SceneTeam team )

{

// Add physics node

PhysicsCharacterNode node = sceneChar.getPhysicNode();

characterNodes.add( node );



rootNode.attachChild( node );

physicsSpace.add( node );

[…]

}

[/java]



So I tried to change it to :

[java]

private void addSceneCharacterToTeam( SceneCharacter sceneChar, SceneTeam team )

{

// Add physics node

PhysicsCharacterNode node = sceneChar.getPhysicNode();

characterNodes.add( node );



Node parent = (Node) battlegroundNode;

parent.updateGeometricState();

parent.attachChild( node );

parent.updateGeometricState();



physicsSpace.add( node );

[…]

}

[/java]



But it doesn’t behave as I wanted :frowning:

  • The character position is messed up. ( I think its something to do with my battleground center not in the origin. I should be able to manage this point )
  • The character doesn’t inherit the lights of the parent node. ( They are invisible if I don’t add a SunLight )
  • I have some error when I try to cast a collision ray though one of them :

    [java]

    java.lang.IllegalStateException: Scene graph must be updated before checking collision

    at com.jme3.scene.Geometry.collideWith(Geometry.java:225)

    at com.jme3.scene.Node.collideWith(Node.java:498)

    [/java]



    I also tried to use :

    [java]

    battlegroundNode.getLocalLightList();

    battlegroundNode.getWorldLightList();

    [/java]

    but it seems that the lists are empty.



    I think I have miss something somewhere but … I don’t know what xD

    If someome can give me a hint …



    Thanks in advance !
2

It depends on where the lights are placed in the scene. If your scene is lit, that means the light should be on the root, so you should see something there

3

Hi,

In fact, I do not wish to add lights to the root node via code in an explicit manner.

I wish to define my lights directly inside my 3D Editor. ( When I create my battleScene )



For example, I have a battleScene that is a small house.









I wish to be able to add some lights via my 3D editor without having to edit the JAVA part.

For that, I see two options :

  • Detecting the lights when adding my .j3o and transfert them to the root node.
  • Add the character as subchilds of the child battleSceme and let them herit the lights of their parent.



    I’m stuck on my two options xD



    PS : Perhaps the problem resides when I add the battleScene. This is not something I’m experienced at, so their may be some options I don’t know when adding the models.

    [java]

    private void createBattlegroundModel( String fileName, float width, float depth )

    {

    //Create 3D model

    battlegroundModel = ViewManager.getAssetManager().loadModel( fileName );



    //
//Scale
//
BoundingBox box = ((BoundingBox)battlegroundModel.getWorldBound());

float currentWidth = box.getXExtent();
float currentDepth = box.getZExtent();

//Scale
float scaleX = width / ( currentWidth * 2 );
float scaleZ = depth / ( currentDepth * 2 );
float scaleY = ( scaleX + scaleZ ) / 2 ;
battlegroundModel.scale( scaleX, scaleY, scaleZ );

battlegroundModel.setLocalTranslation( 0, 0, 0 );
}
[/java]


Edit :
I have also spotted where my point lights are declared inside my XML.
Perhaps the problems come from them :
[java]
<node name="FireLight">
<position x="-17.4648" y="-0.400392" z="-4.05256" />
<scale x="1" y="1" z="1" />
<rotation qx="-0.707107" qy="-0" qz="-0" qw="-0.707107" />
<light name="FireLight" visible="true" type="point" castShadows="false" power="0.1">
<colourDiffuse r="1.02652" g="0.7215" b="0.243195" />
<colourSpecular r="1" g="1" b="1" />
<lightAttenuation range="10000" constant="1" linear="0" quadric="0" />
</light>
</node>
<node name="ExteriorLight">
<position x="34.0681" y="2.44519" z="8.73039" />
<scale x="1" y="1" z="1" />
<rotation qx="-0.707107" qy="-0" qz="-0" qw="-0.707107" />
<light name="ExteriorLight" visible="true" type="point" castShadows="false" power="0.266667">
<colourDiffuse r="0.948811" g="0.910556" b="1.03358" />
<colourSpecular r="1" g="1" b="1" />
<lightAttenuation range="10000" constant="1" linear="0" quadric="0" />
</light>
</node>
[/java]
4

Would this work?

[java]

final Node rootNode = …



scene.breadthFirstTraversal(new SceneGraphVisitor(){

public void visit(Spatial spatial){

for (Light l : spatial.getLocalLightList()){

rootNode.addLight(l);

}

spatial.getLocalLightList().clear();

}

});



[/java]

5

Edit : It works !!! I had done a mistake in my procedure getWorldLightList() → getLocalLightList();

Thanks a lot !





Hmmm…

Is the SceneGraph advisor one of your custom classes ( I didn’t find it inside source library.0

Well, my library that dates from 31-12-2010… I should do an update soon xD

( I didn’t find breadthFirstTraversal either )



So I tried to adapt your code to my use :

[java]

moveBattleGroundsLights( battlegroundNode );

[…]

private void moveBattleGroundsLights( Spatial spatial )

{

for( Iterator<Light> i = spatial.getWorldLightList().iterator(); i.hasNext(); )

{

Light thisLight = i.next();

System.out.println( "Add a light of type " + thisLight.getType().toString() );

rootNode.addLight(thisLight);

this.light = thisLight;

}

spatial.getLocalLightList().clear();



try {

Node node = (Node) spatial;

for( int i = 0; i < node.getChildren().size(); i++ )

{

Spatial child = node.getChild( i );

System.out.println( “Loop on : " + child.getName() );

moveBattleGroundsLights( child );

}

}

catch( Exception e )

{

LogManager.debug( this, spatial.getName() + " cannot be converted into a node” );

}



}

[/java]

I’m visiting all the nodes but… each one seems to have two lights

→ My battleScene became pitch white xD

[java]

Loop on : a0K_ArnanStart_main-scene_node

Add a light of type Point

Add a light of type Point

Loop on : House-node

Add a light of type Point

Add a light of type Point

Loop on : House-entity

Add a light of type Point

Add a light of type Point

Loop on : a0K_ArnanStart_House-ogremesh

Add a light of type Point

Add a light of type Point

Loop on : a0K_ArnanStart_House-geom-1

Add a light of type Point

Add a light of type Point

Loop on : Ground-node

Add a light of type Point

Add a light of type Point

Loop on : Ground-entity

Add a light of type Point

Add a light of type Point

Loop on : a0K_ArnanStart_Ground-ogremesh

Add a light of type Point

Add a light of type Point

Loop on : a0K_ArnanStart_Ground-geom-2

Add a light of type Point

Add a light of type Point

Loop on : Table-node

Add a light of type Point

Add a light of type Point

Loop on : Table-entity

Add a light of type Point

Add a light of type Point

Loop on : a0K_ArnanStart_Table-ogremesh

Add a light of type Point

Add a light of type Point

Loop on : a0K_ArnanStart_Table-geom-3

Add a light of type Point

Add a light of type Point

Loop on : Lader-node

Add a light of type Point

Add a light of type Point

Loop on : Lader-entity

Add a light of type Point

Add a light of type Point

Loop on : a0K_ArnanStart_Lader-ogremesh

Add a light of type Point

Add a light of type Point

Loop on : a0K_ArnanStart_Lader-geom-4

Add a light of type Point

Add a light of type Point

Loop on : FireLight-node

Add a light of type Point

Add a light of type Point

Loop on : ExteriorLight-node

Add a light of type Point

Add a light of type Point

[/java]