U.S. Patent No. 10,864,434: Simulation of multiple connected bodies for real-time application
Issued December 15, 2020, to Square Enix Ltd
Filed/Priority to February 27, 2018
Overview:
U.S. Patent No. 10,864,434 (the ‘434 patent) relates to simulating the movement of multiple, connected bodies in a video game in real-time. The ‘434 patent details a method of simulating the movement of connected bodies by receiving constraints associated with the physical properties of three or more bodies connected by a chord and running them through a loop of instructions for predicting the bodies’ movements.
The state of the bodies including: position, linear velocity, angular velocity, mass, inertia tensor, and orientation of the bodies is received. External force or impulse parameters are also received, the external force parameters being indicative of external forces applied to the connected bodies at a current time step, and the external impulse parameters indicative of external impulses applied to the bodies. The tension experienced in the cord at the current time step based on the external force, impulse parameters, and a generated Jacobian matrix is determined and the state of the bodies for a next time step is updated based on that determination. Representations of the bodies and the cord at the next step are sent for display on a display device at the next time step based on the updated step. The ‘434 patent is a loop of instructions which could lower computing resources for real-time application of the movement of multiple bodies in a video game.
Abstract:
Embodiments relate to simulating the movements of three or more bodies connected on a cord for use in real-time videogame applications. The state of the bodies such as position, velocity, and orientation of the bodies connected by a cord are determined in single pass without iteration. For a given time step and the state of the bodies in the time step, the Jacobian matrix for the connected bodies is calculated. The, the tension in the cord is calculated based on the Jacobian matrix. From the tension, the state of the bodies for the next time step is obtained.
Illustrative Claim:
- A method of simulating movements of connected bodies, comprising: (a) receiving constraint parameters describing constraints associated with physical properties of three or more bodies connected by a cord, wherein the constraint parameters include a mass of the cord that is greater than zero; (b) receiving a state of the bodies including at least one of a position, linear velocity, angular velocity, mass, inertia tensor, and orientation of the bodies at a current time step; (c) receiving external force parameters or external impulse parameters, the external force parameters indicative of external forces applied to the connected bodies at the current time step, the external impulse parameters indicative of external impulses applied to the connected bodies at the current time step; (d) determining a Jacobian matrix for the connected bodies based on the constraint parameters and the state of the bodies for the current time step; (e) determining a tension experienced in the cord at the current time step based on the external force parameters or the external impulse parameters at the current time step and the Jacobian matrix; (f) updating the state of the bodies for a next time step subsequent to the current time step based on the determined tension at the current time step; and (g) sending for display, on a display device, representations of the bodies and the cord at the next time step based on the updated state, wherein each of steps (c) through (f) are performed only once for the current time step.