Re: [JAVA3D] Selecting a 3D primitive

[Anselm Hook]

Walk the scene and find the transformgroup that is the parent of the primitive in question.  Or walk upwards from the primitive in question and try find a transform group above it.  Otherwise manufacture a transform group above it.  Walking the scene is pretty easy.  I hope this is the right take on your question...  I do find it difficult to discover the 'type' of a primitive... for some reason instanceof failed for me when I tried this last.   You may not have a transformgroup above some leaf nodes... or the transformgroup may collect some other stuff you don't want to rotate.   Here is a chunk of (uncleaned) code for doing this:    void find_node_recurse(Object node) {   if( node instanceof TransformGroup ) {    for( Enumeration i = ((Group)node).getAllChildren(); i.hasMoreElements(); ) {     find_node_recurse( i.nextElement() );    }   } else   if( node instanceof Switch ) {    // do nothing   } else   if( node instanceof Group ) {    for( Enumeration i = ((Group)node).getAllChildren(); i.hasMoreElements(); ) {     find_node_recurse( i.nextElement() );    }   } else   if( node instanceof javax.media.j3d.Locale ) {    for( Enumeration i = ((javax.media.j3d.Locale)node).getAllBranchGraphs(); i.hasMoreElements(); ) {     find_node_recurse( i.nextElement() );    }   } else   if( node instanceof VirtualUniverse ) {    for( Enumeration i = ((VirtualUniverse)node).getAllLocales(); i.hasMoreElements(); ) {     find_node_recurse( i.nextElement() );    }   } else   if( node instanceof Appearance ) {    ((Appearance)node).setCapability(Appearance.ALLOW_POLYGON_ATTRIBUTES_WRITE);    PolygonAttributes poly_attrib = new PolygonAttributes();    poly_attrib.setPolygonMode(PolygonAttributes.POLYGON_FILL);    poly_attrib.setCullFace(PolygonAttributes.CULL_BACK);    ((Appearance)node).setPolygonAttributes(poly_attrib);   } else   if( node instanceof Shape3D ) {    ((Shape3D)node).setCapability( Shape3D.ALLOW_APPEARANCE_WRITE );    find_node_recurse( ((Shape3D)node).getAppearance()  );      }  } -----Original Message----- From: JoeB <[EMAIL PROTECTED]> To: [EMAIL PROTECTED] <[EMAIL PROTECTED]> Date: Tuesday, July 20, 1999 9:33 PM Subject: [JAVA3D] Selecting a 3D primitive I need some help with selecting a 3D primitive. If a scene has more than one 3D primitive and I want to choose a specific primitive to rotate, what do I have to do?   Some suggestions of sample code would be great!   thanks