Unigine::NodeExternBase Class
| Header: | #include <UnigineNodes.h> |
| Inherits from: | Base |
The base class that is used to implement logic of custom user-defined nodes. The custom node class should be inherited from NodeExternBase.
Notice
NodeExternBase isn't a node (it isn't inherited from the Node class). So when the engine loads an instance of the custom node class, a NodeExtern node is created. It wraps implementation of the custom node class inherited from the NodeExternBase class.
Usage Example#
To implement logic of a custom node, perform as follows:
Notice
The custom user-defined node can be implemented on the C++ side only. So the example below shows how to implement such node in C++ and then use in both C++ and UnigineScript.
- Inherit your custom node class from NodeExternBase.
- Implement constructors, destructor and all required methods.
- Register the class via addClassID().
- (Optional) If required, export the class and its functions to UnigineScript.
MyNode.h contains implementation of the custom MyNode class inherited from the NodeExternBase class.
Source code (C++)
#include <UnigineNodes.h>
using namespace Unigine;
// inherit a custom class from NodeExternBase
class MyNode : public NodeExternBase
{
public:
// constructors
MyNode();
MyNode(void *node);
// destructor
virtual ~MyNode();
// unique class ID
virtual int getClassID();
// save and restore the node state
virtual int saveState(const StreamPtr &stream);
virtual int restoreState(const StreamPtr &stream);
// save and restore the node pointer
static void savePointer(const StreamPtr &stream, MyNode *node);
static NodeExternBase *restorePointer(const StreamPtr &stream);
// set world transformation of the node
void setWorldTransform(const Math::Mat4 &transform);
};MyNode.cpp contains implementation of MyNode's methods.
Source code (C++)
#include "MyNode.h"
// constructor with no arguments
MyNode::MyNode()
{
Log::warning("MyNode::MyNode(): called\n");
}
// constructor with 1 argument
MyNode::MyNode(void *node)
: NodeExternBase(node)
{
Log::warning("MyNode::MyNode(void*): called\n");
}
// destructor
MyNode::~MyNode()
{
Log::warning("MyNode::~MyNode(): called\n");
}
// returns the class ID of MyNode
int MyNode::getClassID()
{
return 1;
}
// save the node state
int MyNode::saveState(const StreamPtr &stream)
{
Log::warning("MyNode::saveState(): called\n");
return NodeExternBase::saveState(stream);
}
// restore the node state
int MyNode::restoreState(const StreamPtr &stream)
{
Log::warning("MyNode::restoreState(): called\n");
return NodeExternBase::restoreState(stream);
}
// save the node pointer
void MyNode::savePointer(const StreamPtr &stream, MyNode *node)
{
Log::warning("MyNode::savePointer(): called\n");
return NodeExternBase::savePointer(stream, node);
}
// restore the node pointer
NodeExternBase *MyNode::restorePointer(const StreamPtr &stream)
{
Log::warning("MyNode::restorePointer(): called\n");
return NodeExternBase::restorePointer(stream);
}
// set world transformation of the node
void MyNode::setWorldTransform(const Math::Mat4 &transform)
{
getNode()->setWorldTransform(transform);
Log::message("MyNode::setWorldTransform(): called\n");
}In unigine_project.cpp the MyNode class is registered.
Source code (C++)
#include <UnigineEngine.h>
#include "AppSystemLogic.h"
#include "AppWorldLogic.h"
#include "AppEditorLogic.h"
#include "MyNode.h"
int main(int argc,char *argv[]) {
// register the MyNode class
NodeExternBase::addClassID<MyNode>(1);
Unigine::EnginePtr engine(argc,argv);
AppSystemLogic system_logic;
AppWorldLogic world_logic;
AppEditorLogic editor_logic;
engine->main(&system_logic,&world_logic,&editor_logic);
return 0;
}In AppWorldLogic.cpp, approaches to work with the MyNode class are shown: you can directly create an instance of the MyNode class, or you can create an instance of the NodeExtern class by using MyNode's class ID. In both cases, an instance of the MyNode class is created.
Source code (C++)
#include "AppWorldLogic.h"
#include "MyNode.h"
int AppWorldLogic::init() {
// create a MyNode pointer directly
MyNode *my_node_0 = new MyNode();
// call a member function
my_node_0->setWorldTransform(Math::translate(Math::Vec3(0.5)));
// create a NodeExtern instance by MyNode's class ID
NodeExternPtr my_node_1 = NodeExtern::create(1);
// obtain the MyNode pointer
MyNode *my_node_2 = (MyNode*)my_node_1->getNodeExtern();
// call the MyNode member function
my_node_2->setWorldTransform(Math::translate(Math::Vec3(1.0)));
return 1;
}Output
MyNode::MyNode(): called
MyNode::setWorldTransform(): called
MyNode::MyNode(void*): called
MyNode::setWorldTransform(): called
MyNode::~MyNode(): calledExporting to UnigineScript#
To use the custom node on the UnigineScript side, export the class and its functions to UnigineScript.
unigine_project.cpp:
Source code (C++)
#include <UnigineEngine.h>
#include <UnigineInterface.h>
#include "AppSystemLogic.h"
#include "AppWorldLogic.h"
#include "AppEditorLogic.h"
#include "MyNode.h"
int main(int argc,char *argv[]) {
// register the MyNode class
NodeExternBase::addClassID<MyNode>(1);
// export the MyNode class
ExternClass<MyNode> *my_node = MakeExternClassSaveRestoreStatePointer<MyNode>();
my_node->addConstructor();
my_node->addFunction("grab", &MyNode::grab);
my_node->addFunction("release", &MyNode::release);
my_node->addFunction("getNode", &MyNode::getNode);
my_node->addFunction("setWorldTransform", &MyNode::setWorldTransform);
Interpreter::addExternClass("MyNode", my_node);
Unigine::EnginePtr engine(argc,argv);
AppSystemLogic system_logic;
AppWorldLogic world_logic;
AppEditorLogic editor_logic;
engine->main(&system_logic,&world_logic,&editor_logic);
return 0;
}And then use the MyNode class on the UnigineScript side:
Source code (UnigineScript)
#include <core/unigine.h>
int init() {
// create MyNode
MyNode my_node_0 = new MyNode();
my_node_0.setWorldTransform(Mat4(translate(0.0f, 0.0f, 1.0f)));
// create NodeExtern by class ID
NodeExtern node = new NodeExtern(1);
MyNode my_node_1 = class_cast("MyNode", node.getNodeExtern());
my_node_1.setWorldTransform(Mat4(translate(0.0f, 0.0f, -1.0f)));
return 1;
}NodeExternBase Class
Members
template <class Type>
static addClassID ( int class_id ) #
Registers the custom node class with a unique class ID.Source code (C++)
// register the MyNode class
NodeExternBase::addClassID<MyNode>(1);Arguments
- int class_id - Unique class ID.
void copy ( NodeExternBase * node, int is_root ) #
Copies the current custom node into the given one.Arguments
- NodeExternBase * node - Pointer to a target node.
- int is_root - Unique class ID.
BoundBox getBoundBox ( ) #
Returns the bounding box of the custom node.Return value
The bounding box.BoundSphere getBoundSphere ( ) #
Returns the bounding sphere of the custom node.Return value
The bounding sphere.int getClassID ( ) #
Returns a unique class ID.Return value
Unique class ID.Ptr<Node> getNode ( ) #
Returns the Node smart pointer.Return value
Node smart pointer.Ptr<NodeExtern> getNodeExtern ( ) #
Returns the NodeExtern instance that is created on loading the custom node.Return value
NodeExtern smart pointer.int loadWorld ( const Ptr<Xml> & xml ) #
Loads a node state from the Xml.Arguments
Return value
Returns 1 if the node state was successfully loaded; otherwise, 0 is returned.void renderHandler ( ) #
Renders the handler for the custom user-defined node.void renderVisualizer ( ) #
Renders the visualizer for the custom user-defined node.Notice
You should enable the engine visualizer by the show_visualizer 1 console command.
bool saveState ( const Ptr<Stream> & stream ) #
Saves a node state into the stream.Saving into the stream requires creating a blob to save into. To restore the saved state the restoreState() method is used:
Source code (C++)
// initialize a node and set its state
//...//
// save state
BlobPtr blob_state = Blob::create();
node->saveState(blob_state);
// change state
//...//
// restore state
blob_state->seekSet(0); // returning the carriage to the start of the blob
node->restoreState(blob_state);Arguments
Return value
true on success; otherwise, false.bool restoreState ( const Ptr<Stream> & stream ) #
Restores a node state from the stream.Restoring from the stream requires creating a blob to save into and saving the state using the saveState() method:
Source code (C++)
// initialize a node and set its state
//...//
// save state
BlobPtr blob_state = Blob::create();
node->saveState(blob_state);
// change state
//...//
// restore state
blob_state->seekSet(0); // returning the carriage to the start of the blob
node->restoreState(blob_state);Arguments
Return value
true on success; otherwise, false.int saveWorld ( const Ptr<Xml> & xml ) #
Saves a node state into the Xml.Arguments
Return value
1 if the node state was successfully saved; otherwise, 0 is returned.void swap ( NodeExternBase * node ) #
Swaps two custom nodes.Arguments
- NodeExternBase * node - Pointer to the custom node to swap.
void updateEnabled ( ) #
Updates enabled.void updateTransform ( ) #
Updates transformation matrix of the custom node.Last update:
2024-08-16
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