EFFICIENT SYNCHRONIZATION OF BEHAVIOR TREES USING NETWORK SIGNIFICANT NODES

• US 20140372554A1
• Filed: 06/14/2013
• Published: 12/18/2014
• Est. Priority Date: 06/14/2013
• Status: Active Grant

• Current Assignee: Disney Enterprises Incorporated (The Walt Disney Company)
• Original Assignee: Disney Enterprises Incorporated (The Walt Disney Company)
• Inventors: Baum, Kirk, Kharkar, Sandeep V., Marre, Andrew Cantlay, Peterson, Jaren J.
• Granted Patent: US 9,560,131 B2
• Time in Patent Office: Days
• US Class Current: 709/217
• CPC Class Codes: A63F 13/358 Adapting the game course according to the network or server load, e.g. for reducing latency due to different connection speeds between clients
• CPC Class Codes: A63F 2300/5593 involving scheduling aspects
• CPC Class Codes: A63F 2300/638 according to the timing of operation or a time limit
• CPC Class Codes: H04L 67/1095 Replication or mirroring of data, e.g. scheduling or transport for data synchronisation between network nodes
• CPC Class Codes: H04L 67/131 Protocols for games, networked simulations or virtual reality

Abstract

Objects in a virtual space may need to be synchronized between different instances (or different expressions of an instance) of the virtual space that are separated spatially. Objects include characters. Different expressions may be associated with different users and different client computing platforms that are connected by a network. The actions of the same character in two expressions of the same instance of the virtual space may not be synchronized due to network delay, lag, latency, or other delays, or due to joining a session already in progress. Responsive to a determination that an object is not synchronized, a sequence of subsequent states is determined that will result in the object being synchronized.

Claims

1. A system configured to synchronize objects in a virtual space, the system comprising:

electronic storage configured to store behavior trees for objects in a virtual space, wherein individual behavior trees include nodes that correspond to states of the objects, wherein the electronic storage is configured to store a first behavior tree for a first object;

one or more processors configured to execute computer program modules, the computer program modules comprising;

a space module configured to implement an expression of an instance of the virtual space to determine views of the virtual space, wherein the objects include the first object;

a reception module configured to receive current states for the objects over a network; and

a behavior module configured to determine subsequent states of objects from the received current states based on the stored behavior trees such that, responsive to reception of a first current state for the first object, the behavior module determines a first subsequent state for the first object based on the first current state and the first behavior tree.

2. The system of claim 1, wherein the computer program modules comprise a synchronization module configured to synchronize determined subsequent states of the objects with received current states for the objects.

3. The system of claim 2, wherein the first subsequent state is for a first point in time, and wherein the synchronization module is configured such that responsive to reception, by the reception module, of a second current state for the first object for a second point in time that corresponds to the first point in time, the synchronization module determines whether the first object is synchronized by comparing the first subsequent state with the second current state.

4. The system of claim 3, wherein the computer program modules comprise a sequence module configured to determine, responsive to a determination that the first object is not synchronized, a sequence of one or more subsequent states of the first object such that the first object will be synchronized at an end of the sequence.

5. The system of claim 1, wherein actions of objects are implemented as predetermined sequences of states such that individual actions correspond to traversals spanning multiple nodes of the individual behavior trees.

6. The system of claim 1, wherein the electronic storage is configured to store individual behavior trees for individual objects.

7. The system of claim 1, wherein a current state of an individual object corresponds to multiple nodes within a single behavior tree.

8. The system of claim 7, wherein the received first current state corresponds to multiple nodes within the first behavior tree.

9. The system of claim 3, wherein the received current states include timestamps, and wherein determinations by the synchronization module are based on comparisons of timestamps.

10. The system of claim 1, wherein the expression of the instance of the virtual space is associated with a first user.

11. The system of claim 1, wherein the current states for the objects are received from a second expression of the instance of the virtual space, wherein the second expression is associated with a second user.

12. The system of claim 1, wherein the first current state for the first object is received from a non-player character (NPC).

13. The system of claim 5, wherein actions of objects are further implemented by interpolation between the multiple nodes.

14. The system of claim 4, wherein the determined sequence of one or more subsequent states of the first object is different than a sequence of received current states for the first object.

15. The system of claim 4, wherein timing of the determined sequence of one or more subsequent states of the first object is different than timing of a sequence of received current states for the first object.

16. A computer-implemented method for synchronizing objects in a virtual space, the method being performed by one or more processors configured to execute computer program modules, the method comprising:

storing behavior trees for objects in the virtual space, wherein individual behavior trees include nodes that correspond to states of the objects, wherein the behavior trees include a first behavior tree for a first object;

implementing an expression of an instance of the virtual space to determine views of the virtual space, wherein the objects include the first object;

receiving a first current state for the first object over a network; and

determining a first subsequent state of the first object from the received first current state based on the first current state and the first behavior tree.

17. The method of claim 16, wherein the determined first subsequent state is for a first point in time, the method further comprising:

receiving a second current state for the first object that is for a second point in time, wherein the second point in time corresponds to the first point in time; and

determining whether the first object is synchronized by comparing the determined first subsequent state with the received second current state.

18. The method of claim 17, further comprising:

determining, responsive to a determination that the first object is not synchronized, a sequence of one or more subsequent states of the first object such that the first object will be synchronized at an end of the sequence.