# Patent

## Title
Method and device for copying and decoding digitized frames of a special

## Abstract

A virtual reality life object is prevented from performing any behavior that is impossible in a real world, without having to detect the collision of the virtual reality life object with an obstacle. Data for specifying a range in which a virtual reality pet can move around is entered in a moving range control table stored on a hard disk drive for example of an information processing apparatus for providing a virtual reality space. The position of an avatar corresponding to a moving object (or a virtual reality pet) in the virtual reality space is detected and the position of the moving object is generated based on the detected position of the avatar. Next, it is determined whether the generated position of the moving object is in the limited range in which the moving object can move about. If the decision is no, a position in the limited range nearest to the generated position of the moving object is searched for. Then, the position of the moving object is corrected to the position found by the search.

## Background
The present invention generally relates to an information processing apparatus, an information processing method, and an information providing medium. More particularly, the present invention relates to an information processing apparatus, an information processing method, and information providing medium that prevent a virtual reality life object existing in a three-dimensional shared virtual reality space from performing any behavior that is impossible in a real world, without sensing the collision of the virtual reality life object with an obstacle.

A cyberspace service named Habitat (registered trademark) is known in so-called personal computer communications services such as NIFTY-Serve (registered trademark) of Japan and CompuServe (registered trademark) of U.S. in which a plurality of users connect their personal computers via modems and public telephone networks to the host computers installed at the centers of the services to access them in predetermined protocols.

Development of Habitat started in 1985 by Lucas Film of the U.S., operated by Quantum Link, one of U.S. commercial networks, for about three years. Then, Habitat started its service in NIFTY-Serve as Fujitsu Habitat (trademark) in February 1990. In Habitat, users can send their alter egos called avatars (the incarnation of a god figuring in the Hindu mythology) into a virtual city called Populopolis drawn by two-dimensional graphics to have a chat (namely, a realtime conversation based on text entered and displayed) with each other. For further details of Habitat, refer to the Japanese translation "pp. 282-307" of "Cyberspace: First Steps," Michael Benedikt, ed., 1991, MIT Press Cambridge, Mass., ISBNO-262-02327-X, the translation being published on Mar. 20, 1994, by NTT Publishing, ISBN4-87188-265-9C0010.

In the conventional cyberspace systems operated by personal computer communications services such as mentioned above, a virtual street and the inside of a room for example are drawn in two-dimensional graphics. Therefore, moving an avatar in the depth direction is realized simply by moving it up and down in the background of the two-dimensional graphics. This results in a poor expression in simulating walking and movement in a virtual reality space. Also, the two-dimensional virtual reality space in which own avatar and the avatar of another user are displayed is viewed from a viewpoint of a third party, thereby impairing the sense of simulated experience.

To overcome this drawback, a capability that enables a user to walk as desired with the viewpoint of the avatar of the user in a virtual reality space represented in three-dimensional graphics is realized by use of a three-dimensional graphics data description language called VRML (Virtual Reality Modeling Language) as disclosed in Japanese Patent Laid-open No. Hei 09-81781 corresponding to U.S. Pat. application Ser. No. 08/678,340. Considerations about various cyberspaces in which chat is made by use of the avatar of a user are described in NIKKEI Electronics, Sep. 9, 1996, No. 670, pp. 151-159.

Recently, breeding simulation games for breeding tropical fish and a virtual reality creature having artificial intelligence living in a virtual world for example have come to be available as personal computer software programs. A product is also known that displays a simulated pet such as a dog or a cat on an electronic notepad to enjoy the process of its growth (refer to NIKKEI Electronics, Apr. 7, 1997, No. 686, pp. 131-134). In addition, "Tamagotchi" (registered trademark) developed and commercialized by Bandai Co. is widely known that is an egg-sized portable virtual reality pet with a breeding simulation game program as mentioned above incorporated.

Virtual reality pets of this type have a CPU (Central Processing Unit), a ROM (Read only Memory), a RAM (Random Access Memory) and so on mounted on a single-chip LSI (Large Scale Integration), a breeding simulation game program being stored in the ROM, the figure and state of the pet being displayed on an LCD (Liquid Crystal Display) device. The user gives such instructions by operating buttons as "feed" and "clean up" for example necessary for breeding the virtual reality creature as a pet. As a result of caring, the virtual reality creature displayed on the LCD grows stepwise from an egg to a chick to a grown-up bird for example in its external view.

The virtual reality creature is programmed such that proper instructions given help the virtual reality creature grow without problem and improper instructions given make it sick or, in the worst case, die. Further, the virtual reality creature is programmed to make various requests based on the time elapsing from its birth provided by an incorporated calendar timer. For example, in the nighttime zone, the virtual reality creature requests a sleep and, in the mealtime zone, it requests food. In other times, the virtual reality creature requests, at random, snack and play for example. If the user fails to answer these requests properly, the growth of the virtual reality creature may be retarded or its character worsens. If the user answers properly, the life of the virtual reality creature is lengthened.

Meanwhile, Japanese Patent Laid-open No. Hei 07-160853 corresponding to U.S. Pat. No. 5,572,646 discloses a technology applicable to an electronic notepad for example for displaying images according to the growth processes of a virtual reality creature such as an animal or a plant. To be more specific, bit-map images representing the growth processes of a plant character for example are stored in the ROM in the electronic notepad. The plant character according to the degree of growth is displayed on the LCD of the electronic notepad and, at the same time, characters representing plant growing elements (water, light, and fertilizer for example) are displayed. Necessary amounts of these growing elements are inputted by operating corresponding keys on the electronic notepad. The inputted values are set to a water amount register, a light amount register, and a fertilizer amount register respectively in the RAM of the electronic notepad. Based on the values set to these registers, a new degree of growth is computed. Then, the plant character corresponding to the computed degree of growth is read from the ROM to be displayed on the LCD. Thus, the plant growth process according to the state of cultivation by the user is displayed.

Thus, a simulated pet (hereafter also referred to as a virtual reality pet or a virtual reality life object) takes various actions as operated by its keeper, namely the user. In a conventional virtual reality space, in order to avoid taking actions that are impossible in the real world, namely colliding an obstacle and passing through it for example, a virtual reality pet senses the collision or the possibility thereof with an obstacle to circumvent the collision, searches for a moving route (for example, a route not passing through a house wall) that is possible in the real world, and moves along the route found by the search. However, for a virtual reality pet to detect the collision with an obstacle while moving about, a complicated program for controlling the movement of the virtual reality pet is required and the CPU load increases due to the execution of such a program, thereby hampering prompt CPU processing.

It is therefore an object of the present invention to provide an information processing apparatus, an information processing method, and an information providing medium that prevent a virtual reality pet from taking actions impossible in the real world by presetting a range in which the virtual reality pet is allowed to move without sensing the collision of an obstacle.

In carrying out the invention and according to a first aspect thereof, there is provided an information processing method for providing a virtual reality space to a client apparatus connected to connected a network, comprising steps of: generating data about a new position of an object existing in the virtual reality space; correcting, based on data for specifying a moving range of the object stored in a storage device, the generated position to a position in the specified moving range; and moving the object to the corrected position.

In carrying out the invention and according to a second aspect thereof, there is provided an information processing apparatus for providing a virtual reality space to a client apparatus connected to a network, comprising: a storing means for storing data for specifying a moving range of an object existing in the virtual reality space; a generating means for generating data about a new position of the object; a correcting means for correcting the generated position to a position in the specified moving range; and a moving means for moving the object to the corrected position.

In carrying out the invention and according to a third aspect thereof, there is provided an information providing medium for providing control information for providing a virtual reality space to a client apparatus connected to network, the control information comprising steps of: generating data about a new position of an object existing in the virtual reality space; correcting, based on data for specifying a moving range of the object stored in a storage device, the generated position to a position in the specified moving range; and moving the object to the corrected position.

These and other objects of the invention will be seen by reference to the description, taken in connection with the accompanying drawing, in which:

FIG. 1 is a diagram illustrating a relationship between a sensor, an event, a routing, and a script;

FIG. 2 is a diagram illustrating a routing;

FIG. 3 is a block diagram illustrating an example of a constitution of a shared virtual reality space providing system associated with the present invention;

FIG. 4 is a block diagram illustrating an example of a constitution of the client PC 1 shown in FIG. 3;

FIG. 5 shows display photographs for describing an operation of the system shown in FIG. 3;

FIG. 6 shows display photographs for describing another operation of the system shown in FIG. 3;

FIG. 7 shows display photographs for describing still another operation of the system shown in FIG. 3;

FIG. 8 is a diagram illustrating an example of a growth parameter control table;

FIG. 9 shows a photograph for describing an action panel;

FIG. 10 is a diagram illustrating passing of a growth parameter;

FIG. 11 is a diagram for describing virtual reality life object nodes constituting a 3D object;

FIG. 12 shows a display photograph indicative of a display example corresponding to the nodes shown in FIG. 11;

FIG. 13 is a diagram for describing virtual reality life object physique index;

FIG. 14 is a diagram for describing virtual reality life object mood index;

FIG. 15 is a diagram for describing virtual reality life object activity index;

FIG. 16 is a diagram for describing virtual reality life object intelligent quotient;

FIG. 17 is a display photograph for describing an example of a shared virtual reality space;

FIG. 18 is a display photograph for describing another example of the shared virtual reality space;

FIG. 19 is a display photograph for describing still another example of the shared virtual reality space;

FIG. 20 is a display photograph for describing yet another example of the shared virtual reality space;

FIG. 21 is a display photograph for describing a different example of the shared virtual reality space;

FIG. 22 is a display photograph for describing a still different example of the shared virtual reality space;

FIG. 23 is a display photograph for describing a yet different example of the shared virtual reality space;

FIG. 24 is a display photograph for describing a separate example of the shared virtual reality space;

FIG. 25 is a display photograph for describing a still separate example of the shared virtual reality space;

FIG. 26A is a schematic diagram of the example of FIG. 25 viewed from top;

FIG. 26B is a cross section of the example of FIG. 25 as viewed from top;

FIG. 27 is a flowchart describing an autonomous action of a virtual reality pet in a specified range; and

FIG. 28 is a schematic diagram illustrating a locus of a virtual reality pet walking about along path D of FIG. 25.

This invention will be described in further detail by way of example with reference to the accompanying drawings.

First, there will be described VRML (Virtual Reality Modeling Language), which is a descriptive language enabling users to integrally handle three-dimensional information by use of the framework of the WWW (World Wide Web) for providing a variety of information through the Internet, a computer network built worldwide.

Meanwhile, for an information providing system available on the Internet, the WWW developed by CERN (European Center for Nuclear Research) in Switzerland is known. This technology allows a user to browse information including text, image and voice for example in the hyper text form. Based on HTTP (Hyper Text Transfer Protocol), the information stored in a WWW server terminal is sent asynchronously to terminals such as personal computers.

The WWW server is constituted by server software called an HTTP daemon and an HTML file in which hyper text information is stored. The wording "daemon" means a program for executing management and processing in the background upon working on UNIX. The hyper text information is described in a description language called HTML (Hyper Text Makeup Language). In the description of a hypertext by HTML, a logical structure of a document is expressed in a format specification called a tag enclosed by "<" and ">". Description of linking to other information is made based on link information called an anchor. A method in which a location at which required information is stored by the anchor is URL (Uniform Resource Locator).

A protocol for transferring a file described in HTML on the TCP/IP (Transmission Control Protocol/Internet Protocol) network is HTTP. This protocol has a capability of transferring a request for information from a client to the WWW server and the requested hyper text information stored in the HTML file to the client.

Used by many as an environment for using the WWW is client software such as Netscape Navigator (trademark of Netscape Communications Corp. of US) called a WWW browser.

Use of the WWW browser allows users to browse files, which are called home pages, corresponding to URLs stored in WWW servers on the Internet built worldwide, thereby performing net-surfing by sequentially following home pages linked to each other to access a variety of WWW information sources.

Recently, a VRML browser has been developed by extending this WWW. The VRML browser displays a three-dimensional space described in a three-dimensional graphics language called VRML that enables description of a three-dimensional space and setting of hypertext links to objects drawn in three-dimensional graphics, thereby allowing users to follow these links to sequentially access WWW servers.

Details of VRML are described in the Japanese translation of "VRML: Browsing & Building Cyberspace," Mark Pesce, 1995, New Readers Publishing, ISBN 1-56205-498-8, the translation being entitled "Getting to Know VRML: Building and Browsing Three-Dimensional Cyberspace," translated by Kouichi Matsuda, Terunao Gamaike, Shouichi Takeuchi, Yasuaki Honda, Junichi Rekimoto, Masayuki Ishikawa, Takeshi Miyashita and Kazuhiro Hara, published on Mar. 25, 1996, Prenticehall Publishing, ISBN4-931356-37-0, as well as "Most Recent Trend of VRML And CyberPassage," Koichi Matsuda and Yasuaki Honda, the bit Magazine, Kyoritsu Publishing, 1996, Vol. 28, No. 7, pp. 29-36, No. 8, pp. 57-65, No. 9, pp. 29-36, No. 10, pp. 49-58.

The authorized and complete specifications of the Virtual Reality Modeling Language Version 2.0, ISO/IEC CD 14772 released on Aug. 4, 1996 is made public in http://webspace.sgi.com/moving-worlds/spec/index.html and its Japanese version is made public in http://www.webcity.co.jp/info/andoh/VRML/vrml2.0/spec-jp/index.html.

Further, for the browser for VRML 2.0 and the software for shared server, Sony Corporation, the present applicant, has developed and commercialized as "Community Place Browser/Bureau (registered trademark), of which beta version is downloadable from the Internet home page of Sony, http://vs.sony.co.jp.

To build a three-dimensional virtual reality space by use of VRML 2.0, a VRML file for representing a desired content is created by generating graphics data indicative of the shape and behavior of an object (or a model) in the virtual reality space by use of VRML (model creation), adding the model in the virtual reality space displayed on the screen to a switch (or a sensor) for generating an event when the user clicks the model with the mouse for example, programming (or scripting) a script for realizing an event to be generated when the sensor is pointed, and relating (or routing) between graphics data and script (hereafter, common nodes such as write specified in graphics data, script, and VRML are also generically referred to as nodes) such as operating the sensor and starting the script.

For example, http://www.ses.co.jp/SES/STAFF/kan/howto/howtol.html describes in detail a method of writing VRML 2.0 and provides sample data.

The following describes a mechanism for implementing an autonomous behavior in a VRML space, a new feature provided by VRML 2.0, not supported by VRML 1.0.

VRML 2.0 data is constituted by a node and a field, which is basically written as follows:

Node {Field(s)}

In the above-mentioned file syntax, "Field(s)" may be omitted but "Node" and the braces "{", "}" cannot. A field passes a variable to a node to specify a node parameter. If the field is omitted, a default is used. There are two types of fields. A single-value field (SF) having only one value and a multiple-value field (MF) having two or more values. Each single-value field begins with "SF" and each multiple-value field begins with "MF."

VRML 2.0 realizes an autonomous movement (behavior) of an object according to an event to be caused by an operation performed on the object arranged in a three-dimensional virtual reality space and a timer event that occurs when a preset time has been reached. The mechanism of this Behavior is realized by the cooperation of three elements; sensor, routing, and script as follows. object arranged in a three-dimensional virtual reality space beforehand senses an external event based on a change in its field value to generate an event in a VRML scene. program for specifying the behavior of the object based on a routing described as a VRML file. particular event is received. The external script, which has received the event transmitted by the routing, executes the processing based on the description and then changes the value of the field of the corresponding node in the VRML scene based on the result of the processing and the description of the routing.

For sensor nodes, the VRML 2.0 defines TouchSensor that causes an event when the pointing device passes over a specified object or the same is clicked by the user, ProximitySensor that causes an event when ViewPoint (of the user) enters a specified region, and TimeSensor that is caused every time a preset time interval elapses, for example.

The following describes the mechanism of Behavior in more detail. As described above, the mechanism of Behavior is implemented by a sensor, an event, a routing, and a script.

The sensor is functionally divided into the following two types:

the type for sensing a user operation; and

the type for sensing a system change.

The sensor for sensing a user operation provides a software switch related to an object arranged in a three-dimensional virtual reality space. The sensor for sensing a system change starts a timer preset to a start time. These sensors sense these external events and convert them into events inside VRML.

The event indicates data for transmitting information between associated nodes in VRML. Actually, a change in a field value described in a VRML file is transmitted as an event.

The routing is a mechanism for specifying to which node an event sensed by the sensor capability is to be transmitted. Actually, the routing specifies a path of information transmission by the event.

The script provides an input/output port, performs some computation from an inputted event, and outputs a result of the computation. The script is not restricted to a particular language. In the current stage, the script can be written in Java (registered trademarks of Sun Microsystems, Inc. of US) and JavaScript noticed in the Internet, C language widely used in ordinary systems, Tcl/Tk and PERL widely used in UNIX, or Visual Basic provided by Microsoft Corporation. Thus, VRML 2.0 does not depend on a particular script language (in the course of defining VRML 2.0 specifications, employment of VRMLScript as particular language specifications was discussed but this idea was eventually discarded).

The following describes the processing means of Behavior with reference to FIG. 1. The processing by Behavior is diagramatically represented as shown in FIG. 1. The following describes flows of processing signals.

(1) Sensor node

As described above, the sensor node is largely classified into two types; a sensor for sensing a user operation and a sensor for sensing a system change.

The sensor for sensing a user operation has sensor nodes such as TouchSensor and PlaneSensor for sensing a mouse click on a three-dimensional object and passing of a pointing device over a plane of the three-dimensional object. The sensor for sensing a system change has TimeSensor adapted to generate an event when a preset time has been reached.

In the example of FIG. 1, it is assumed that TouchSensor is attached to a sphere. When an user clicks the sphere, this event is sensed by TouchSensor. This event is sensed because the field value of the eventOut field of TouchSensor changes. Generally, one mouse click operation generates two events; namely, the timing of pressing the mouse button and the timing of releasing the mouse button.

Then, this event is routed by the routing description part.

(2) Routing

"Route" as shown in FIG. 2 specifies routing of this event.

When an event caused in the sensor description part is transmitted to the eventout field of the Route and then to a script node to be described below, the event is passed to the external file, upon which the Behavior capability is executed.

(3) Script node

This is a node for mediating the interlocking between a VRML file and an external script. This node specifies the language in which the description is made and a file name according to the description format of the script node, and the eventIn field and the eventOut field in order to give and take the event to and from the external script file. Available script files include those written in Java, JavaScript, C language, Tcl/Tk, PERL, and Visual Basic.

In actual processing, the processing is transmitted to the script file in which the routed event is described in the script node and the external script file is executed. The external script file is received through eventIn (event entrance) defined in it and the processing described in that file is executed. When this processing has come to an end, the processing result is returned through eventOut (event exit) to the routing of the VRML file. The VRML file executes this returned result, upon which the series of Behavior processing operations come to an end.

Use of the mechanism of Behavior to be realized by the above-mentioned cooperation between the sensor, the routing, and the script allows the user to dynamically change the external view (shape, attitude, size, color, and so on) or behavioral sequence for example of an object arranged in a three-dimensional virtual reality space by clicking an object resembling a switch also arranged in this space.

Details of the Behavior mechanism is disclosed in Section 4 "Concept" in the Specifications "The Virtual Reality Modeling Language Version 2.0," ISO/IEC CD 14772, Aug. 4, 1996 which is made public in http://webspace.sgi.com/moving-worlds/spec/part1/concepts.html and its Japanese version http://www.webcity.co.jp/info/andoh/VRML/vrml2.0/spec-jp/part1/concepts. html. This section describes the key concepts to use of the VRML specifications. These concepts include various general node-related items such as a method of linking a node to a scene graph, a method in which a node generates or receives an event, a method of generating a node type by a prototype, a method in which a node type is added to VRML and then exported to be made available from outside, and a method of incorporating a script to operate as a program into a VRML file.

The following describes a technology in which, by application of the mechanism for realizing the above-mentioned autonomous movement (Behavior) of VRML 2.0, a virtual reality life object is created in a shared virtual reality space, growth parameters (external growth or internal growth (personality)) that change according to the generation of an event such as a user operation or passing of a predetermined time are controlled by a server, and a script program for dynamically changing one or both of the external view (shape, attitude, size, color, and so on) and the behavioral sequence of the created virtual reality life object based on the growth parameters transferred from this server is interpreted and executed, thereby displaying the virtual reality life object according to the growth parameters.

FIG. 3 is a schematic diagram illustrating an entire system practiced as one preferred embodiment of the present invention.

In FIG. 3, a VRML browser and a WWW browser are installed in client PCs (Personal Computers) 1 through 3, which are connected to the Internet 7 through IPs (Internet Service Providers) 4 through 6.

A LAN (Local Area Network) 9 connected to the Internet 7 through a router 8 is connected to a WWW server 10, a WLS (World Location Server) 11, a shared server 12, AO (Application Object) servers 13 and 14, a mail server 15, and a communication server 16. The WWW server is provided with hard disk (HDD) 10a and 10b, the WLS server 11 with a hard disk 11a, the shared server 12 with a hard disk 12a, the AO server 13 with a hard disk 13a, the AO server 14 with a hard disk 14a, the mail server 15 with a hard disk 15a, and the communication server 16 with a hard disk 16a.

The communication server 16 is connected to a telephone 18 and a facsimile 19 through a public telephone network 17, to a portable telephone terminal 23 through a wireless telephone service provider 20 in a wireless manner, and to a paging terminal 24 through a paging service provider 21 in a wireless manner.

The following describes a hardware constitution of the client PC 1 with reference to FIG. 4.

In FIG. 4, a CPU (Central Processing Unit) 30 of the client PC1 controls the other components of this client PC. A hard disk drive (HDD) 31 stores VRML contents composed of a VRML 2.0 file and a growth script program for a shared virtual reality life by Java (registered trademark of Sun Microsystems, Inc. of US), and data about the keeper of the virtual reality creature. A CD-ROM drive 32 reads VRML contents stored in a CD-ROM disc 33. A ROM 34 stores a BIOS (Basic Input/Output System) and so on. A sound processor 35 is connected to a microphone 36 and left and right speakers 37 and 38. A MODEM 39 connects this client PC to the Internet 7. An I/O (Input/Output) interface 40 is connected to a mouse 41 and a keyboard 42. A graphics processor 43 incorporates a VRAM (Video RAM) 44. A CRT monitor 45 displays an image signal outputted from the graphics processor 43. A RAM 46 stores various computer programs.

In the RAM 46, Netscape Navigator, which is a WWW browser operating on Windows 95 (registered trademark of Microsoft Corporation of U.S.), the Java interpreter, and Community Place Browser, which is a VRML 2.0 browser developed by Sony Corporation, are read at run time and are ready for execution by the CPU 30.

The VRML 2.0 browser is installed with QvLib, which is a VRML syntax interpreting library (parser) developed by Silicon Graphics, Inc. in US and offered without charge, RenderWare, which is a software renderer developed by Criterion Software Ltd. in England, and so on or other parser and renderer having equivalent capabilities.

As shown in FIG. 3, Community Place Browser transfers data of various types with Netscape Navigator, a WWW browser, based on NCAPI (Netscape Client Application Programming Interface) (registered trademark).

Receiving an HTML file and VRML content (including a VRML file and a script program written in Java) from the WWW server 10, Netscape Navigator stores them in the local HDD (Hard Disk Drive) 31. Netscape Navigator processes the HTML file to display text and images on the CRT monitor. On the other hand, Community Place Browser processes the VRML file to display a three-dimensional virtual reality space on the CRT monitor and changes the behavior of the object in the three-dimensional virtual reality space according to the result of processing of the script program by the Java interpreter.

It should be noted that the other client PCs 2 and 3 have generally the same constitutions, not shown, as that of the PC 1 described above.

The following describes the operation of the above-mentioned preferred embodiment.

First, a sequence spanning from actually downloading the VRML content through the Internet to providing a multi-user environment in which one virtual reality space is shared by plural users is described with reference to FIGS. 5 through 7.

Referring to FIG. 5, the home page of the Web site that provides the VRML content is browsed by use of the WWW browser as indicated by arrow 101. In this example, home page http://pc.sony.co.jp/sapari/ is browsed. Next, as indicated by arrow 102, the users of the client PC 1 and the client PC 2 download the VRML content composed of the VRML 2.0 file and the script program (the growth script program written in Java) for realizing an autonomous movement (Behavior) in the VRML space.

Obviously, the VRML content provided in the CD-ROM disc 33 may be read by the CD-ROM drive 32.

Then, as shown in FIG. 6, in the client PC 1 and the client PC 2, the VRML 2.0 file downloaded and stored in the local HDD 31 is interpreted and executed by Community Place Browser, which is a VRML 2.0 browser. Next, as indicated by arrow 103, the client PCs ask the WLS 11 for the URL of the shared server 12 based on VSCP (Virtual Society Server Client Protocol). In response, as indicated by arrow 104, the WLS 11 references the shared server URL control table stored in the HDD 11a and sends the URL of the shared server 12 to the client PC 1 and the client PC 2.

Using this URL, the client PC 1 and the client PC 2 are connected to the shared server 12 as shown in FIG. 7. As a result, as shown with arrow 105, shared messages associated with the position and movement of the shared 3D object are transmitted through this shared server 12. These messages are transferred as shown with arrow 106 to realize the multi-user environment.

For detailed description of the procedure of the above-mentioned connection, refer to Japanese Patent Laid-open No. Hei 9-81781 corresponding to U.S. patent application Ser. No. 08/678,340.

The following describes the AO server 13 that controls the behavior of a virtual reality life object existing in the shared virtual reality space. The AO server 13 transfers data associated with the virtual reality life object with the shared server 12 based on VSAP (Virtual Society Server Application Protocol). The AO server is functionally divided into a plurality of AOs. For example, a universal AO, only one of which exists in a virtual reality space, covers all over that virtual reality space, monitoring the login and logout operations of all users. The universal AO uses the attribute capability of Community Place Browser to understand the contents of the registry of each client PC and write predetermined information to the registry. In addition, the universal AO issues a user identification (equivalent to a 3D object ID when one user can rear one virtual reality pet) and enters that user identification into the growth parameter control table for example. The universal AO also can broadcast information to all users joining the shared virtual reality space.

An object AO controls the virtual reality objects left in a virtual reality space other than the virtual reality life objects and, when any of these objects is picked up by a user, controls the picked up object as a possession of that user.

An agent AO controls a virtual reality pet that a user can rear in a shared virtual reality space and assigns one virtual reality pet to one user for example.

An area AO sets a special capability to a predetermined area in a shared virtual reality space. For example, the area AO allows a battle area to make virtual reality life objects compete with each other. The area AO allows a chat area to store all chat logs. The user can retrieve past remarks for use in currently performed conversation. The area AO allows a trash recycle area to discard objects thrown in this area.

All AOs including the object AO, the agent AO, and the area AO are generated and controlled by the universal AO.

As shown in FIG. 8, the data in the growth parameter control table are largely classified into virtual reality life object data and keeper data.

The virtual reality life object data includes a 3D object ID for uniquely identify a 3D object in one shared virtual reality space, three-dimensional coordinate values representing the virtual reality life object in the shared virtual reality space, a type of a creature such as a monkey or a cat selected by the keeper, the gender of the creature, its nickname given by the keeper, a date initialized by the keeper, namely the birth date of the virtual reality life object, a world name (a world name of domicile of origin) given to the virtual reality space in which the virtual reality life object was born, and growth parameters of the virtual reality life object.

The growth parameters are largely classified into physical parameters for specifying the external growth of the virtual reality life and mental parameters for specifying the internal growth of the virtual reality life object reflecting its character.

The physical parameters are composed of height (in centimeters), weight (in kilograms), physique index, appetite index, health index, and remaining life time (in hours).

The mental parameters include intelligence quotient, language capability index, sociability index, independence index, activity index, and mood index.

These parameters are sequentially updated to values computed by a predetermined growth parameter computing equation based on a timer event caused when certain time has passed after the birth date initialized by the keeper, and an access event and an operation event caused by a call message and an operation message from the client PC.

FIG. 9 shows capabilities of an action panel displayed beside the main window of the VRML browser on the CRT monitor screen 45 of the client PC 1.

In FIG. 9, "A" denotes a calling button represented as "Active." This button is clicked to call the virtual reality pet or wake up the sleeping virtual reality pet.

"B" denotes a button represented as "Sleep" for putting the virtual reality pet to bed.

"C" denotes a feeding button. This button is clicked to feed the virtual reality pet.

"D" denotes a praise button. This button is clicked to praise the virtual reality pet by smiling at it.

"E" denotes a play button. This button is clicked to play tag, in which the keeper chases the virtual reality pet until the same is blocked by a wall and cannot be escaped therefrom.

"F" denotes a scold button. This button is clicked to scold the virtual reality pet for discipline.

"G" denotes a groom button. This button is clicked to groom the virtual reality pet by brushing.

As shown in FIG. 10 for example, when the call button A is clicked (the action panel is operated) on the own client PC 1 and a resultant call message is sent to the AO server 13 through the shared server 12 (step S1), growth parameter update processing is performed on the growth parameter control table based on that access event (step S3). Based on this access event, the appetite index, the health index, and the mood index are each incremented by 0.1 point from 1/10 to 10/10.

If the feeding button C is clicked for example and a resultant message is sent to the AO server 13 (step S2), the weight of the growth parameter increase every time the operation event occurs, along which the physique index is incremented by 0.1 point from 1/10 to 10/10 (step S3).

Then, when the timer event occurs as a result of passing of a predetermined time, the weight, one of the growth parameters, decreases, decrementing the physique index by 0.1 point (step S3).

For example, the growth parameters including this. physique index are transferred (step S4) to the client PC 1 of the original keeper and another client PC 2 sharing the virtual reality space by multicast processing (step S5) of the shared server 12 every time the growth parameters are updated.

The client PC 1 executes the growth script program described with a processing procedure for controlling the autonomous behavior resulted from the virtual reality pet growth based on the growth parameters (step S6), changes the field values of the nodes constituting the 3D object for representing the virtual reality pet in the VRML file (step S7), performs rendering on the virtual reality pet on which the changed field values are reflected (step S8), and displays the rendered virtual reality pet on the main window of the VRML browser on the CRT monitor screen 45 of the client PC 1.

The same processing performed by the client PC 1 is also performed on the other client PC 2 sharing the virtual reality space. Consequently, rendering is performed on the appearance of the virtual reality pet on which the field value changed along the growth of the virtual reality pet is reflected, and the rendered virtual reality pet is also displayed on the main window of the VRML browser on the CRT monitor of the other client PC 2.

FIG. 11 shows a relationship between part 0 through part 5 corresponding to the nodes constituting a 3D object for representing a virtual reality pet in the VRML file. FIG. 12 shows an example of displaying these parts. Part 0 corresponds to the head of the virtual reality pet, part 1 to its body, part 2 and part 3 to its right and left arms, and part 4 and part 5 to its right and left legs.

Changing the field values of the nodes corresponding to these parts 0 through 5 can dynamically change the external view (shape, attitude (orientation), size, color, and so on) and the behavioral sequence of each part of the virtual reality pet. These are all realized by the processing of the growth script program based on the growth parameters. Namely, these are realized by use of the mechanism of Behavior to be realized by the cooperative operation between the sensor, the routing, and the script defined in VRML 2.0.

Therefore, unlike the conventional method of displaying images of a virtual reality creature of portable electronic pet, it is unnecessary to store the bit-map images representing each growth process of the character of virtual reality creature in the ROM beforehand. Namely, use of the mechanism of Behavior can continuously and dynamically change the physique and behavior of a virtual reality pet according to its growth process for example.

FIG. 13 is a conceptual diagram in which the physique of a virtual reality pet is dynamically changed as the virtual reality pet grows and its physique index changes. As the virtual reality pet grows in age, its face becomes that of an adult and its physique becomes larger. If the physique index is small, the virtual reality pet becomes thin; if it is large, the pet becomes thick.

FIG. 14 is a conceptual diagram in which the countenance of the virtual reality pet is dynamically changed as its mood index changes. When the mood index is high, the face of the virtual reality pet smiles; when it is low, an angry expression appears on the face.

FIG. 15 is a conceptual diagram in which the behavioral sequence of each part of the virtual reality pet is dynamically changed as the activity index of the virtual reality pet changes. When the activity index is low, only a small movement such as bending of knees; when it high, the virtual reality pet can wave its arms or shake its head for example.

FIG. 16 is a conceptual diagrams in which hair is added to the virtual reality pet or glasses are put on it as the intelligence quotient of the virtual reality pet changes.

The intelligence quotient, one of the growth parameters, is incremented by 0.1 point based on the access event caused by the operation of the calling button A shown in FIG. 9, thereby changing the appearance of the virtual reality pet as shown in FIG. 16.

The language index is incremented by 0.1 point according to the increasing age of the virtual reality pet based on the access event caused by the operation of the call button A shown in FIG. 9 or the timer event, thereby changing the style of text in chat sentence editing processing. For example, chat of a virtual reality pet having a small point is performed using hiragana or katakana Japanese syllabary and a chat of a virtual reality pet having a large point is performed using text including kanji Chinese characters.

The sociability index is incremented or decremented by 0.1 point according to the frequency of chat with the keeper. If the frequency is high, sociability increases; if it is low, sociability decreases. A virtual reality pet having a sociable and positive character takes on good attitude and countenance. Conversely, a virtual reality pet having an introvert and negative character takes on poor attitude and countenance.

The independence index is incremented by 0.1 point as a virtual reality pet ages based on timer event, gradually becoming independent of the keeper, rejecting commands of the keeper for example.

The activity index is determined based on the age, appetite index, and health index, affecting the behavior of a virtual reality pet as shown in FIG. 15. Also, the activity index is incremented by 0.1 point based on the event caused by operating the play button E shown in FIG. 9, affecting the behavior of the virtual reality pet such as gradually quickening getaway. The weight of the virtual reality pet is decreased to decrement its physique index, dynamically changing its appearance as shown in FIG. 13.

The mood index is determined by the access event caused by operating the call button A shown in FIG. 9 and the access frequency based on timer event, thereby affecting the countenance of a virtual reality pet as shown in FIG. 14.

On the other hand, the keeper data in the growth parameter control table shown in FIG. 8 is composed of the name of the keeper, a means (or method) for making contact with the keeper, and the address of the contact.

If the contacting means is 0, contact to the keeper is performed by a message statement through electronic mailing via the Internet 7. If the contacting means is 1, contact to the keeper is performed by converting text data of a message statement into a voice by an automatic reading tool on the communication server 16 and inputting the voice into the analog telephone 18. If the contacting means is 2, contact to the keeper is performed by a message statement to the portable telephone terminal 23 by use of an electronic mail service based on the data transmission protocol of wireless communication. If the contacting means is 3, contact to the keeper is performed by a written document to the facsimile 19. If the contacting means is 4, contact to the keeper is performed by a message statement to the pager terminal 24.

The keeper data as described above is controlled to realize the capability of contacting the keeper by use of the existing communication infrastructure to be describe later and the capability of simplified operation of a virtual reality pet by use of the existing communication infrastructure.

The above-mentioned system is summarized as follows. Namely, the growth parameter (indicative of outer growth or inner growth (personality)) of a virtual reality life object existing in a shared virtual reality space is controlled by the AO server 13, this growth parameter changing with occurrence of a predetermined event (an event caused by a user operation or passing of predetermined time). Based on the growth parameter transferred from the AO server 13, the script for dynamically changing one or both of the appearance (shape, attitude, size, or color) and the behavioral sequence of the virtual reality life object is interpreted to display the virtual reality life object according to the growth parameter on the client PCs 1 and 2.

The AO server 13 for controlling the autonomous behavior of a virtual reality life object existing in a shared virtual reality space is provided with a control table for controlling growth parameters for the virtual reality life object that change with occurrence of a predetermined event (an event caused by a user operation or passing of a predetermined time). A growth parameter read from the control table upon request from a client or occurrence of a predetermined demand is sent to one or both of the requesting client and another client.

As described above, the growth parameter is a value indicative of the degree of external growth to be calculated based on the occurrence of a predetermined event (an event caused by a user operation or passing of a predetermined time) from the birth of a virtual reality life object. Therefore, the outer growth parameter defines the outer change of a virtual reality creature or a virtual reality pet (AO) according to the age from baby to grown-up to aged.

The growth parameter is also a value indicative of the degree of inner growth (character) to be calculated based the occurrence of a predetermined event (a user operation or passing of a predetermined time) for a virtual reality life object. For example, a virtual reality life object having a sociable and positive character takes on good attitude and countenance. Conversely, a virtual reality life object having a dark and negative character takes on bad attitude and countenance. Thus, the change in the character of a virtual reality creature or a virtual reality pet (AO) is specified by the inner growth parameter.

For the inner growth parameter, a different value is calculated according to the type of an event for a virtual reality life object, updating the degree of the inner growth. If the character of a virtual reality pet for example is controlled by the AO server 13, 0.1 point is added to a predetermined index of the growth parameter according to the type of a message sent from each client; for example, every time the virtual reality pet is talked to in chat. Every time, the virtual reality pet is praised by pressing of the praise button D, 0.2 point is added. Every time the virtual reality pet is scolded by pressing of the scold button F, 0.2 point is subtracted from the predetermined index. Thus, the calculation is performed based on predetermined arithmetic equations.

The AO server 13 for controlling the autonomous behavior of a virtual reality life object in a shared virtual reality space is provided with a growth parameter control table indicative of the degree of growth of each virtual reality life object. This control table holds the birth date of each virtual reality life object. Based on the elapsed time starting from this birth date, the growth parameter according to the age of each virtual reality life object is calculated. The control table is updated by the newly calculated growth parameter.

The autonomous behaviors of plural virtual reality life objects in a shared virtual reality space are independently controlled by the AO server 13 (the single AO server 13 may control plural growth parameter control tables or the AO server 13 and the AO server 14 may control the plural control tables separately). Thus, the growth parameter control tables indicative of the growth degrees of different virtual reality life objects may be provided separately to control the growth parameters of the different virtual reality life objects independently.

In addition, various applications such as described below for example are possible.

For example, the AO server 13 for controlling the autonomous behavior of a virtual reality life object in a shared virtual reality space may be provided with a control table for controlling the ID (a nickname for example of the virtual reality life object set by user) of a client who has accessed the virtual reality life object (the control items of this control table may be included in the growth parameter control table or this control table may be provided independently). Based on this control table, an event indicative of an intimacy emotional expression may be started according to the access by the client having this ID. Thus, holding the degree of intimacy (access count and contents) on the AO server 13 can realize a pet (virtual reality life) object that approaches its keeper when the keeper has entered the world (the shared virtual reality space).

The ID of a client who has set or reset a virtual reality life object may be stored in the growth parameter control table as the keeper of this virtual reality life object. Updating of this ID is disabled until the life of the virtual reality life object expires. At the time of the expiration, this ID may be deleted. This can realize a virtual reality pet that is loyal to its keeper who has given birth to it (namely set it in the shared virtual reality space). Further, when the life of a virtual reality life object expires (namely, it is reset), a child of this virtual reality life object may be automatically generated and the ID of the keeper of its parent may be set to this child. This makes the child pet be also loyal to the keeper of its ancestor.

The AO server 13 may be provided with a history control table for controlling the history of a client who has set or reset a virtual reality life object. The client higher in access frequency than other clients can start a behavioral sequence indicative of more intimate emotional expression. As the access frequency lowers, the degree of intimacy lowers, thereby realizing a whimsical pet of which degree of intimacy changes with access frequency.

If the movement of a virtual reality life object is controlled according to the position of client in a shared virtual reality space, the virtual reality life object immediately appears just in front of the client (keeper) when the client enters the shared virtual reality space, thereby realizing the virtual reality life object that always follows its keeper about.

An intimate expression of feelings may be realized by making a virtual reality life object periodically report an event encountered in a shared virtual reality space (for example, an event of being fed by another client) to its client through a text-based chat window.

Experience of an event in a shared virtual reality space may be reported from the virtual reality life object to the client through a voice chat to provide an intimacy emotional expression. Alternatively, this report may be made through a voice chat capability as an analog voice message based on text-to-voice conversion supported by text reading software. Alternatively still, several types of voice messages may be sampled and compressed to be stored as digital voice compressed data in the hard disk (of the AO server 13 or the client PC 1). Then, an optimum voice message is selectively read from the hard disk, decompressed, and reported to the client as an analog voice message through the voice chat capability. For the conversion between text and voice, the technology disclosed in Japanese Patent Laid-open No. 09-214486 corresponding to U.S. patent application Ser. No. 08/789,083 is available.

The following describes the capability of notification to the client based on an existing communication infrastructure and the capability of simplifying the operation of a virtual reality pet based on an existing communication infrastructure.

For example, if the appetite index of a virtual reality life object increases or its remaining life time goes below a predetermined value, the virtual reality life object (the AO server 13) notifies, through the mail server 15 or the communication server 16, its keeper at the keeper's address of contact of this change by use of the contacting means (FIG. 8) previously set to the growth parameter control table. If the keeper cannot immediately access the personal computer under situations that the keeper is away from the personal computer or the personal computer itself is malfunctioning for example, the keeper can later check requests of the virtual reality pet and make communication with it.

On the other hand, a service provider for providing services for virtual reality pet breeding such as described so far can evoke a motivation of a kind that the user must soon access the virtual reality pet. This provides a by-product that the service provider can ensure regular access, contributing to its stable management.

The following describes a particular example for realizing the above-mentioned notification capability based on an existing communication infrastructure.

The communication server 16, one of the servers for controlling the autonomous behavior of a virtual reality life object in a shared virtual reality space, is provided with a communication control table (a table corresponding to the keeper data in the growth parameter control table shown in FIG. 8) for controlling the type of a message notification means (or a message notification method) for making notification to the user, or the keeper of each virtual reality life object and controlling the address of contact of the keeper. As the state of the virtual reality life object changes (the communication server 16 is notified of this change by the AO server 13), the message is sent to the address of contact by use of the communication means registered in the communication control table. This allows actual communication from the shared virtual reality world to the real world.

The ID for identifying each user, or the keeper of each virtual reality life object and the history access by the user having this ID are controlled by this communication control table. Based on the access history, a message "I miss you" for example may be sent to a user who has not accessed his or her virtual reality life object for over a certain period.

Further, based on the access history, an optimum message statement may be selected from among plural message statements. The day after the day on which access has been made by the user, a message "Thank you for playing with me. Let's play again" for example may be sent from the virtual reality life object to its keeper. If no access has been made for over one week for example, a message "Are you busy these days? Please come to play with me sometimes" for example is sent.

A transition in the state of a virtual reality life object is sensed based on the updated content of the growth parameter control table, an optimum message statement is selected from among plural message statements, and the selected message is sent. For example, the day after the day on which the virtual reality life object has been fed much, a message "I'm still full" for example is sent. If no access has been made for one week for example, a message "I'm starving to death" for example is sent. In a scenario in which a virtual reality life object is aged one year in one week, its birthday comes every week and a message "I have become 10 years old today. Please look at grown-up me" for example is sent. If the allocated remaining life time is nearly expiring, a message "I have to go somewhere far away soon. Please be with me when I die" for example is sent.

The mail server 15 may be provided with a part of the communication control table associated with electronic mail to send a text-based message to the keeper of each virtual reality life object at his or her electronic mail address (including his or her ID) by the communication control table of the mail server 15.

In addition to an electronic mail transmitted through the Internet 7, a message may be sent from the communication server 16 through the public telephone network 17 to the portable telephone terminal 23 based on wireless communication or to the pager terminal 24 to be displayed on the LCD of the wireless telephone terminal or the pager.

Alternatively, the telephone number (including the ID) of the user of each virtual reality life object may be controlled by the communication control table to automatically call the user at his or her registered telephone number from the communication server 16, thereby sending a voice message. In this case, this notification may be made as an analog voice message based on text-to-voice conversion supported by text reading software through the ordinary telephone 8 or the portable telephone terminal 23. Alternatively, several types of voice messages may be sampled and compressed to be stored as digital voice compressed data in the hard disk (of the AO server 13 or the client PC 1). Then, an optimum voice message is selectively read from the hard disk, decompressed, and reported to the client as an analog voice message.

The facsimile number (including the ID) of the user of each virtual reality life object may be controlled by the communication control table to automatically call the user at this facsimile number, thereby sending a message to the facsimile 19.

Further, by use of a terminal such as the telephone 18 that has received the above-mentioned message from the virtual reality pet, two-way communication may be made between the keeper and its virtual reality pet from this terminal by a simplified operation.

The following describes a particular example of realizing the capability of performing a simplified operation on a virtual reality pet by use of an existing communication infrastructure.

For example, the shared server 12 can interpret an operation command returned with the ID (caller ID) of the user through the portable telephone terminal 23 or the telephone 18, recognize the operation command as a message to the corresponding virtual reality life object, send the message to the AO server 13, and reflect the content of the message onto the state transition (updating of a growth parameter) of the virtual reality life object.

For the above-mentioned returned operation command, a DTMF (Dual-Tone Multi-Frequency) signal that is generated when a push button on the telephone 18 is pressed for example may be used.

In addition, by use of Web-On-Call (registered trademark) voice browser by NetPhonic Communications Inc. for example, various notifications to a virtual reality pet may be made. This voice browser allows access to servers from the ordinary telephone 18 by voice. This voice browser has a text reading capability, so that a mail from a virtual reality pet can be heard in voice. Moreover, this voice browser can also send text by facsimile or electronic mail.

It should be noted that the shared server 12, the AO servers 13 and 14, the mail server 15, and the communication server 16 execute various capabilities in a shared manner, thereby realizing a service for providing a shared virtual reality space to client PCs as a whole system.

The following describes a chat capability to be executed in this shared virtual reality space. Chat is classified into public chat and personal chat. In public chat, conversation uttered by one client (user) at a predetermined location in the shared virtual reality space is transmitted to other nearby clients (users).

In personal chat, conversation is made only with a specified party. This specification is performed by clicking the mouse button on a desired virtual reality life object while pressing the shift key of the keyboard 42 for example. When the other party of chat is specified, chat made by the client who has made that specification is directed only to the specified party.

In voice chat, contents of chat are transmitted in a voice signal; in text chat, they are transmitted in text. In voice chat, voice data captured by the microphone 36 is transmitted to the clients (users) nearby or specified virtual reality life objects to be sounded from the speakers 37 and 38 of the PCs of these clients.

In text chat, text entered from the keyboard 42 is transmitted also to the clients (users) of nearby or specified virtual reality life objects to be displayed on the CRT monitor 45 of the client PCs.

The user can select between voice chat and text chat as required.

The following describes particular display examples that appear on the CRT monitor of a client PC. FIG. 17 shows a display example on the CRT monitor 45 to be displayed when the client PC 1 accesses the shared server 12. In this example, message "Connected to Community Place Bureau" is superimposed on an image of three-dimensional shared virtual reality space. It should be noted that a chat content display area "Chat Log:" and various action buttons are disposed on the right side of this screen.

To select a virtual reality pet to be reared in the shared virtual reality space, the client clicks "Multi User" item in the screen. When this item is clicked, a menu bar appears as shown in FIG. 18. From the menu bar, the client selects "Select Pet." Then, "View Pet" window appears as shown in FIG. 19, in which various virtual reality pet images are displayed. The client selects a desired one of these virtual reality pets. It should be noted that the images of virtual reality pets displayed in the "View Pet" window are the initial images, namely the images at their births. As described earlier, the image of each virtual reality pet gradually changes as it grows. After the selection, the client presses the "SELECT" button with the mouse 41.

When the selection of the virtual reality pet has been completed, a window "Registration" for registering the information about the selected virtual reality pet appears as shown in FIG. 20. The client enters the name of the virtual reality pet "Pet Nickname," the name of the owner (keeper of the pet) "Owner Name," and the address and telephone number "Address/Telephone No." of the owner from the keyboard 42.

Further, the client selects a communication tool as the above-mentioned contacting means or notification means from "E-mail," "Telephone," "PHS-mail (wireless communication mail)," "Facsimile," and "Pocket Bell (pager)."

FIG. 21 shows an example in which a monkey for example has been selected as the virtual reality pet. As described earlier, this virtual reality pet (monkey) grows based on growth parameters to be updated by various events. FIG. 22 shows a state in which the virtual reality pet has more grown than that shown in FIG. 21. As the virtual reality pet grows in age, its face becomes that of an adult and its physique becomes larger.

Thus, changes closer to reality can be enjoyed in a shared virtual reality space.

The following describes, with reference to particular display examples, a method of preventing a virtual reality pet from performing an action that is impossible in a real world without sensing the collision with an obstacle when moving in a three-dimensional shared virtual reality space. FIG. 23 shows a display example of a bird's eye view of a three-dimensional shared virtual reality space to be provided when the client PC 1 for example accesses the shared server 12. FIG. 24 shows an image obtained by looking down a part of the three-dimensional virtual reality space of FIG. 23 from one side thereof.

An action impossible in a real world is an action in which a virtual reality pet collides a wall A.sub.2 of a house A.sub.1 and then penetrates into the wall A.sub.2 for example. In a real world, if a pet collides the wall A.sub.2, the pet stops at that position or moves along with wall A.sub.2.

FIG. 25 shows an image obtained by looking down another part of the three-dimensional virtual reality space of FIG. 23 from one side thereof. In this example, an arena B.sub.1 is higher than an arena B.sub.2 by s step C and a path D is shown with positions E1 through E9 being corners or branch points. An action impossible in a real world in this example is that, when a virtual reality pet is walking from the arena B.sub.2 to the arena B.sub.1, it collides the step C without climbing the same and penetrates into under the arena B.sub.1 for example. In a real world, when a pet comes to the step C, the pet climbs the same to reach the arena B.sub.1.

A shared virtual reality space providing apparatus to which the present invention is applied sets beforehand, in a shared three-dimensional virtual reality space, a range in which a virtual reality pet can move to limit the movement of the virtual reality pet so as to prevent the virtual reality pet from making any movement that is impossible in a real world.

The path D shown in FIG. 25 represents the range in which the virtual reality pet can move. The following partially shows a program for setting the path D to a three-dimensional shared virtual reality space. It should be noted that the following program is formed by a Java script.

FIG. 26A shows a schematic diagram of an image. obtained by viewing the display example of FIG. 25 from top thereof. FIG. 26B shows a schematic diagram of an image obtained by viewing the display example of FIG. 25 from the side along path link E2-E7. The following describes the contents of the program for setting a moving range of a virtual reality pet with reference to FIGS. 26A and 26B. It should be noted that positional nodes N1 through N9 represent positions corresponding to positions E1 through E9 of FIG. 25. The path link herein is a line connecting positional nodes, being equivalent to a path in a shared virtual reality space.

Class name PathNode (lines 1 through 6) declared to be public class is a class for setting the positional nodes N1 through N9 of FIGS. 26A and 26B. On line 2, coordinates of x-axis, y-axis, and z-axis for the positional nodes N1 through N9 are set. It should be noted that, in this example, the x-axis direction is parallel to path link N4N5, the z-axis direction is parallel to path link N2N4, and the y-axis direction is vertical to the x-axis and z-axis as shown in FIGS. 26A and 26B. On line 3, a node type is set. On line 4, a path link formed by linking positional nodes is held in a vector (list) format.

In PathLink (lines 7 through 14) declared to be public class, the conditions of path link N1N2, path link N2N3, path link N3N4, path link N4N5, path link N5N6, path link N6N7, path link N7N1, path link N1N8, path link N8N9, path link N9N6, and path link N3N8 are set. On line 9, the width of the path link as a path and the diameter of the path link as an arena are specified. On line 10, a path link type is specified. Here, the path link may be a path or an arena for example. On line 11, a positional node array is controlled.

On line 12, it is determined whether the values of the positional node x-axis coordinate and z-axis coordinate are on the path link or not. On line 13, the y-axis coordinate (height) of the positional node is calculated from the x-axis coordinate and the z-axis coordinate.

The following describes an autonomous behavior of a virtual reality pet in the above-mentioned range (for example, the path D of FIG. 25) with reference to the flowchart of FIG. 27.

In step S21, data for specifying a range in which a virtual reality pet can move is entered into a moving range control table stored on the HDD 13a for example. In step S22, the position of the avatar corresponding to the virtual reality pet is detected. In step S23, based on the detected position of the avatar, the position of the virtual reality pet is generated. The virtual reality pet is made follow the avatar while maintaining a predetermined distance from the avatar.

In step S24, it is determined whether the position of the virtual reality pet generated in step S23 is within a limited range in which the virtual reality pet can move about. If the decision is no, a position in the limited range nearest to the generated position of the virtual reality pet is searched for in step S25.

In step S26, the position of the virtual reality pet is corrected to the position found in step S25. In step S27, the virtual reality pet moves further following the avatar.

If the decision is yes in step S24, the virtual reality pet moves further following the avatar in step S27.

Thus, a range in which a virtual reality pet can move may be set beforehand in a three-dimensional shared virtual reality space, thereby preventing the virtual reality pet from performing a behavior impossible in a real world without having the virtual reality pet detect the collision with an obstacle for example.

In addition, as shown in FIG. 28, random numbers are controlled corresponding to the moving range control table so as to allow the virtual reality pet to freely move within the moving range. For example, a random number control table, not shown, may be arranged, thereby allowing the virtual reality pet to move at random in the moving range based on the data in the random number control table.

In the foregoing, an example of the program for setting the moving range of a virtual reality pet has been described. Actually, this program is accompanied by a path information setting routine, a decision routine to decide whether a coordinate that has been set is found on a particular path, and a routine for calculating a height in a given coordinate on a particular path, for example.

According to the above-mentioned preferred embodiments of the present invention, data for specifying a moving range in which a virtual reality life object existing in a shared virtual reality space is stored, data about a new position of the virtual reality life object in the shared virtual reality space is generated, the generated position is corrected to the position of the specified moving range, and the virtual reality life object is moved to the corrected position. This novel constitution prevents the virtual reality pet from performing any behavior that is impossible in a real world without having to detect the collision of the virtual reality pet with an obstacle.

While the preferred embodiments of the present invention have been described using specific terms, such description is for illustrative purposes only, and it is to be understood that changes and variations may be made without departing from the spirit or scope of the appended claims.

## Claims

1. An information processing method for providing a virtual reality space to a client apparatus connected to a network, comprising steps of: reality space; stored in a storage device, the generated position to a position in the specified moving range; and

2. The information processing method according to claim 1, wherein said data for specifying said moving range of said object includes data indicative of a moving path and data indicative of a width of said moving path.

3. The information processing method according to claim 1, wherein said object is a virtual reality life object.

4. The information processing method according to claim 1, wherein said object is set responsive to a user of said client apparatus connected to said virtual reality space.

5. The information processing method according to claim 4, wherein said data generating step generates the data such that said object is positioned within a predetermined distance from an avatar representing a user in said virtual reality space.

6. An information processing apparatus for providing a virtual reality space to a client apparatus connected to a network, comprising: existing in said virtual reality space; the specified moving range; and

7. An information providing medium for providing control information for providing a virtual reality space to a client apparatus connected to network, said control information comprising steps of: reality space; stored in a storage device, the generated position to a position in the specified moving range; and