Inherit from CollisionNode

C++ coding using Panda3D
16

i try to inherit from CollisionNode but my code doesn’t work!

#include "pandaFramework.h"
#include "pandaSystem.h"
#include <collisionNode.h>
#include <collisionSphere.h>
#include <collisionRay.h>
#include <collisionTraverser.h>
#include <collisionHandlerQueue.h>
 
PandaFramework framework;
CollisionTraverser trav;
CollisionHandlerQueue* queue;
CollisionRay* ray;

class MyObject : public CollisionNode {
public:
        MyObject(string name) : CollisionNode(name) {
        }

        static TypeHandle get_class_type() {
            return _type_handle;
        }

        static void init_type() {
            CollisionNode::init_type();
            register_type(_type_handle, "MyObject", CollisionNode::get_class_type());
        }
        
        
        virtual TypeHandle get_type() const {
            return get_class_type();
        }

        virtual TypeHandle force_init_type() {
            init_type();
            return get_class_type();
        }



    private:
        static TypeHandle _type_handle;
};

TypeHandle MyObject::_type_handle;

void clickOnObject(const Event* ev, void* data) {
    WindowFramework* win = framework.get_window(0);
    float x = (2 * win->get_graphics_window()->get_pointer(0).get_x()) / ((float)win->get_graphics_window()->get_x_size())- 1;
    float y = (2 * win->get_graphics_window()->get_pointer(0).get_y()) / ((float)win->get_graphics_window()->get_y_size())- 1;
    ray->set_from_lens(framework.get_window(0)->get_camera(0), x, y);
    trav.traverse(framework.get_window(0)->get_render());
    cout << queue->get_num_entries() << endl;
}

int main(int argc, char *argv[]) {
    framework.open_framework(argc, argv);
    framework.set_window_title("My Panda3D Window");
    WindowFramework *window = framework.open_window();
    framework.get_window(0)->enable_keyboard();
    
    MyObject* obj = new MyObject("hi");
    obj->add_solid(new CollisionSphere(0, 0, 0, 2));
    obj->set_into_collide_mask(BitMask32::all_on());
    
    NodePath path(obj);
    path.reparent_to(window->get_render());
    path.set_pos(-10, -10, -10);
    path.show();
    window->get_camera_group().look_at(path);
    
    
    queue = new CollisionHandlerQueue();
    CollisionNode* cnode= new CollisionNode("ray");
    ray = new CollisionRay();
    cnode->add_solid(ray);
    NodePath cpath(cnode);
    cpath.reparent_to(window->get_camera_group());
    trav.add_collider(cpath, queue);
    
    framework.define_key("mouse1", "click", clickOnObject, NULL);
 
    framework.main_loop();
    framework.close_framework();
    return (0);
}

If i replace this line

MyObject* obj = new MyObject("hi");

with this

CollisionNode* obj = new CollisionNode("hi");

it work!!

why??

thanks!!