Archive 17/01/2023.

Detecting Collisions

Sean221

I’m having trouble with collisions. I looked on the forums and found that i should be using

SubscribeToEvent(_node, E_NODECOLLISION, URHO3D_HANDLER(Main, HandleCollision));

but how do i tell which rigidbody has collided with the object?

Also can someone tell me why when i try and put the SubscribeToEvent in a different class that isn’t inheriting from Sample it doesn’t recognize it?

If anyone else cant figure it out this worked for me
RigidBody* body = static_cast<RigidBody*>(eventData[NodeCollision::P_BODY].GetPtr());

Eugene

Maybe I didn’t understand the question, but event parameter contain enough data, don’t they?

github.com

urho3d/Urho3D/blob/ee054a1507cb3518c57d4ebc43cfd6dc93de9a27/Source/Urho3D/Physics/PhysicsEvents.h#L90

    
      
          URHO3D_EVENT(E_NODECOLLISIONSTART, NodeCollisionStart)

          {

              URHO3D_PARAM(P_BODY, Body);                    // RigidBody pointer

              URHO3D_PARAM(P_OTHERNODE, OtherNode);          // Node pointer

              URHO3D_PARAM(P_OTHERBODY, OtherBody);          // RigidBody pointer

              URHO3D_PARAM(P_TRIGGER, Trigger);              // bool

              URHO3D_PARAM(P_CONTACTS, Contacts);            // Buffer containing position (Vector3), normal (Vector3), distance (float), impulse (float) for each contact

          }

          

          /// Node's physics collision ongoing. Sent by scene nodes participating in a collision.

          URHO3D_EVENT(E_NODECOLLISION, NodeCollision)

          {

              URHO3D_PARAM(P_BODY, Body);                    // RigidBody pointer

              URHO3D_PARAM(P_OTHERNODE, OtherNode);          // Node pointer

              URHO3D_PARAM(P_OTHERBODY, OtherBody);          // RigidBody pointer

              URHO3D_PARAM(P_TRIGGER, Trigger);              // bool

              URHO3D_PARAM(P_CONTACTS, Contacts);            // Buffer containing position (Vector3), normal (Vector3), distance (float), impulse (float) for each contact

          }

          

          /// Node's physics collision ended. Sent by scene nodes participating in a collision.

          URHO3D_EVENT(E_NODECOLLISIONEND, NodeCollisionEnd)

You shoud have your class derived from the Object. Should be enough.

Sean221

How would i go about getting the URHO3D_PARAM?

ive tried RigidBody* body = static_cast<RigidBody*>(eventData[P_BODY].GetPtr());

but that didnt work

Eugene

What about NodeCollision::P_BODY? Well, just use any sampe or piece of engine code as reference.