My own xml nodes

[CodingMarmot]

Hi!

Is it possible to create my own nodes (with custom name and attributes) and use them inside a graph resource xml along with the other nodes?

Thanks in advance

[Stefan]

Hi!

You can do so by deriving from Graph::Node.

In the header file, write:

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#include "murl_graph_node.h" #include "app_i_my_node.h"   namespace Murl {     namespace App     {         class MyNode : public IMyNode, public Graph::Node         {             // Declare the attributes here:               MURL_DECLARE_FACTORY_OBJECT_BEGIN(App::MyNode)                 MURL_DECLARE_FACTORY_OBJECT_PROPERTY(PROPERTY_MY_ATTR)             MURL_DECLARE_FACTORY_OBJECT_END(App::MyNode)                           static INode* Create(const Graph::IFactory* factory);           public:             virtual Graph::INode* GetNodeInterface();             virtual const Graph::INode* GetNodeInterface() const;           protected:             MyNode(const Graph::IFactory* factory);             virtual ~MyNode();             virtual Bool DeserializeBaseAttribute(Graph::IDeserializeAttributeTracker* tracker);               // Use member variables to store attribute values.               SInt32 mMyAttr;         };     } }

Then implement in the CPP file:

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using namespace Murl;   // Define the attributes here:   MURL_DEFINE_FACTORY_OBJECT_BEGIN(App::MyNode)     MURL_DEFINE_FACTORY_OBJECT_PROPERTY(PROPERTY_MY_ATTR, "myAttr") MURL_DEFINE_FACTORY_OBJECT_END(App::MyNode)   Graph::INode* App::MyNode::Create(const Graph::IFactory* factory) {     return new MyNode(factory); }   App::MyNode::MyNode(const Graph::IFactory* factory) : Graph::Node(factory) , mMyAttr(0) { }   App::MyNode::~MyNode() { }   Graph::INode* App::MyNode::GetNodeInterface() {     return this; }   const Graph::INode* App::MyNode::GetNodeInterface() const {     return this; }   Bool App::MyNode::DeserializeBaseAttribute(Graph::IDeserializeAttributeTracker* tracker) {     switch(tracker->GetBaseAttributeProperty(GetProperties()))     {         case PROPERTY_MY_ATTR:             tracker->GetAttributeValue(mMyAttr);             return true;           // handle other attributes here           default:             return Graph::Node::DeserializeBaseAttribute(tracker);     } }

You may want to override the InitSelf, ProcessLogicSelf, etc. methods from Graph::Node to add custom behavior.

Finally, you need to register/unregister the node in your App class by overriding these methods from AppBase:

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Bool App::MyApp::RegisterCustomFactoryClasses(IAppFactoryRegistry* factoryRegistry) {     factoryRegistry->GetGraphFactoryRegistry()->RegisterNodeClass(App::MyNode::GetClassInfo());     return true; }   Bool App::MyApp::UnregisterCustomFactoryClasses(IAppFactoryRegistry* factoryRegistry) {     factoryRegistry->GetGraphFactoryRegistry()->UnregisterNodeClass(App::MyNode::GetClassInfo());     return true; }

Now you can use:

1	<App::MyNode myAttr="42"/>

Or:

1	<MyNode myAttr="42"/>

[CodingMarmot]

Thank you very much for your help!
This is exactly what I wanted.

I knew there has to be an easy way.

[yothsoggoth]

Is this information still valid, or does it need to be updated slightly?

I tried this with murl_1.00.5225beta, however I get a bunch of compiler errors with the macros (MURL_DECLARE_FACTORY_OBJECT_BEGIN, MURL_DECLARE_FACTORY_OBJECT_PROPERTY and MURL_DECLARE_FACTORY_OBJECT_END)


P.S. I know some forums frown upon resurrecting old threads like this, if that's the case just let me know and I'll create a new thread for my questions .

[dizzy]

Thanks for the info; the way how custom nodes are defined has changed indeed. Here's an updated version of the above class that reflects the necessary changes:


Header file snippet:

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#include "murl_graph_node.h"   namespace Murl {     namespace App     {         class MyNode : public Graph::Node         {             // Define the class, including its base class             MURL_FACTORY_OBJECT_DERIVED_CLASS(App::MyNode, Murl::Graph::Node)               // Define node properties, this creates a member variable for each property and assigns a given default value.             MURL_FACTORY_OBJECT_PROPERTIES(App::MyNode,                                            (PROPERTY_MY_ATTR_1, mMyAttr1, 42,  Graph::SInt32Property),                                            (PROPERTY_MY_ATTR_2, mMyAttr2, "42", Graph::StringProperty))               // Define the attributes for deserialization; these bind to individual properties defined above             MURL_FACTORY_OBJECT_ATTRIBUTES(App::MyNode,                                            (ATTRIBUTE_MY_ATTR_1, "myAttr1", mMyAttr1, COMPONENT_SINGLE, ACCESS_SINGLE, ELEMENT_SINGLE),                                            (ATTRIBUTE_MY_ATTR_2, "myAttr2", mMyAttr2, COMPONENT_SINGLE, ACCESS_SINGLE, ELEMENT_SINGLE))               // The static creation method             static INode* Create(const Graph::IFactory* factory);           public:             virtual Graph::INode* GetNodeInterface();             virtual const Graph::INode* GetNodeInterface() const;           protected:             MyNode(const Graph::IFactory* factory);             virtual ~MyNode();               virtual Bool DeserializeBaseAttribute(Graph::IDeserializeAttributeTracker* tracker);         };     } }

CPP file snippet:

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using namespace Murl;   // No need for macros in the CPP file anymore, this is all done in the // header file now.   Graph::INode* App::MyNode::Create(const Graph::IFactory* factory) {     return new MyNode(factory); }   App::MyNode::MyNode(const Graph::IFactory* factory) : Graph::Node(factory) {     // Also, no need to initialize members. this is done in the     // MURL_FACTORY_OBJECT_PROPERTIES macro. }   App::MyNode::~MyNode() { }   Graph::INode* App::MyNode::GetNodeInterface() {     return this; }   const Graph::INode* App::MyNode::GetNodeInterface() const {     return this; }   Bool App::MyNode::DeserializeBaseAttribute(Graph::IDeserializeAttributeTracker* tracker) {     switch (tracker->GetBaseAttribute(GetAttributeInfo()))     {         case PROPERTY_MY_ATTR_1:             return mMyAttr1.DeserializeValue(tracker);           case PROPERTY_MY_ATTR_2:             return mMyAttr2.DeserializeValue(tracker);               // handle other attributes here           default:             return Graph::Node::DeserializeBaseAttribute(tracker);     } }

This is just a basic example using two simple properties/attributes. There's a bunch of other data types available, see the file murl/base/include/engine/graph/murl_graph_property.h; however we are still lacking thorough documentation on the whole topic of user-defined node creation.

Feel free to ask if you need something more specific.

As for resurrecting old threads: We're quite relaxed about doing so as long as it's not totally off-topic or exhaustive

Best regards,

dizzy