JP2009011567A - Game program and game apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To allow a player to intuitively recognize the position of an object in a virtual three-dimensional space. <P>SOLUTION: This game apparatus allows a display device to display a player's object being present in the virtual three-dimensional space. This game apparatus calculates a position of the intersection of a straight line passing through the position of the player's object and facing a predetermined first direction with another predetermined object as a first position and draws a shade 54 of the player's object in the first position. This game apparatus calculates a position of the intersection of a straight line passing through the position of the player's object and facing a second direction non-parallel to the first direction with another predetermined object as a second position and draws a shade 55 of the player's object at the second position. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a game program and a game apparatus, and more particularly to a game program and a game apparatus for displaying an object in a three-dimensional virtual space.

Patent Document 1 describes a game process in a scene where a ball is thrown high in a ball game such as a baseball game or a soccer game. In this game process, for example, in a baseball game, when a batter hits a ball and flies high, a shadow of the ball off the display screen is displayed on the ground along with a fielder on the ground. By displaying the shadow of the ball in this way, the player can know the position of the ball even if the ball is off the screen. That is, the player who operates the fielder can catch the ball by operating the fielder toward the position of the shadow of the ball.
JP 2002-58866 A

  In the baseball game as described above, the fielder that is the operation target of the player moves on the ground that is the two-dimensional plane, so that the player has only to recognize the position of the ball on the two-dimensional plane. However, in a game where a character moving in a three-dimensional space is operated, the player can only recognize the position of the character on the plane by simply displaying the shadow of the character on the ground. It is not sufficient for recognizing the position of the character.

  Therefore, an object of the present invention is to provide a game program and a game apparatus that allow a player to intuitively recognize the position of an object in a virtual three-dimensional space.

  The present invention employs the following configuration in order to solve the above problems. Note that the reference numerals in parentheses and supplementary explanations in this section show the correspondence with the embodiments described later in order to help understanding of the present invention, and do not limit the present invention.

  A first invention is a game program (60) that is executed by a computer (CPU 10 or the like) of a game device (3) that displays an object (player object 53) that exists in a virtual three-dimensional space on a display device (TV 2). is there. The game program causes the computer to execute a first position calculation step (S23), a first shadow drawing step (S25), a second position calculation step (S35), and a second shadow drawing step (S38). In the first position calculating step, the computer calculates, as the first position, the position of the intersection of a straight line passing through the position of the object and facing a predetermined first direction and a predetermined other object. In the first shadow drawing step, the computer draws the shadow (54) of the object at the first position. In the second position calculating step, the computer calculates, as the second position, the position of the intersection of the straight line passing through the position of the object and pointing in the second direction not parallel to the first direction and the predetermined other object. In the second shadow drawing step, the computer draws the shadow (55) of the object at the second position.

  In the second invention, a predetermined shadow drawing area (71) may be set in the three-dimensional space. At this time, the game program causes the computer to further execute an area determination step (S32) for determining whether or not an object exists in a predetermined shadow drawing area set in the three-dimensional space. The second shadow drawing step is executed only when it is determined in the area determining step that the position of the object exists within the shadow drawing area.

  In the third invention, the storage means (main memory) of the game apparatus may store shadow drawing area data (63) in which the projection direction is associated with each shadow drawing area. At this time, in the second position calculation step, the computer calculates the second position with the projection direction associated with the shadow drawing area where the object exists in the shadow drawing area data as the second direction.

  In the fourth invention, the first direction may be a gravitational direction set in a three-dimensional space.

  In a fifth aspect, the game program may cause the computer to further execute a gravity direction changing step (S7) for changing the direction of gravity according to the game situation.

  In a sixth aspect, in the second shadow drawing step, the computer may draw a shadow so that the display form is different from the shadow drawn in the first shadow drawing step (see FIG. 8).

  In a seventh aspect, in the second position calculating step, the computer may calculate the second position only for a predetermined object (player object). At this time, in the second shadow drawing step, the computer draws a shadow only for a predetermined object. The game program causes the computer to further execute a third position calculating step and a third shadow drawing step. In the third position calculating step, the computer calculates, as the third position, the position of the intersection point between the straight line pointing in the third direction that is not parallel to the second direction and another object other than the predetermined object. In the third shadow drawing step, the computer draws a shadow of an object other than the predetermined object at the third position.

  In the eighth invention, the predetermined object may be a terrain object fixedly arranged in the three-dimensional space.

  In a ninth aspect, in the first shadow drawing step, the computer may change the darkness of the shadow based on the distance from the position of the object to the first position.

  In a tenth aspect, in the second shadow drawing step, the computer may change the darkness of the shadow based on the distance from the position of the object to the second position.

  In an eleventh aspect, in the first shadow drawing step, the computer may change the size of the shadow based on the distance from the position of the object to the first position.

  In a twelfth aspect, in the second shadow drawing step, the computer may change the size of the shadow based on the distance from the position of the object to the second position.

  Further, the present invention may be provided in the form of a game device having a function equivalent to that of the game device that executes each step in the first to twelfth inventions.

  According to the first invention, two shadows projected in two different directions with respect to the object are attached. In order to recognize the position of the object in the three-dimensional space, it was not sufficient to attach one shadow to the object. However, as in the first invention, two shadows projected in two different directions are attached. Thus, the player can intuitively recognize the position of the object in the three-dimensional space.

  According to the second invention, only when an object exists in a predetermined shadow drawing area, two shadows are attached to the object. According to this, by setting a shadow drawing area at a place where two shadows need to be added, it is possible to omit the process of drawing a shadow at an unnecessary place, so that a shadow can be generated efficiently. The processing load on the computer can be reduced.

  According to the third invention, the producer can arbitrarily set the direction in which the second shadow is projected. Therefore, since the second shadow can be generated in the optimum direction for each shadow drawing area, the position of the object in the three-dimensional space can be easily recognized by the player.

  According to the fourth invention, the direction in which one shadow is projected is set as the direction of gravity, so that the shadow is generated in a natural direction. Thereby, a virtual three-dimensional space can be naturally expressed.

  According to the fifth aspect of the invention, it is possible to provide an unprecedented new game in which the direction of gravity changes according to the game situation.

  According to the sixth aspect of the invention, the display of the two shadows (for example, the shape) is made different so that the player can distinguish and recognize the two shadows. Thus, the player can determine which direction of gravity is by looking at the two shadows. In particular, when the direction of gravity changes according to the game situation as in the fifth aspect of the invention, it is effective for the player to correctly recognize the direction of gravity using two shadows.

  According to the seventh aspect, in the second position calculating step and the second shadow drawing step, processing is executed only for a predetermined object. Accordingly, the processing in the above step can be omitted for other objects (for example, wall objects) other than the predetermined object, so that the second shadow can be generated efficiently, and the processing burden on the computer is reduced. Can be reduced.

  According to the eighth aspect, by displaying the shadow on the terrain object, the player can easily recognize the position of the object in the three-dimensional space.

  According to the ninth to twelfth inventions, the darkness or size of the shadow changes in accordance with the distance from the object position to the shadow position. According to this, the player can more easily recognize the distance, and more easily recognize the position of the object in the three-dimensional space.

(Overall configuration of game system)
A game system 1 including a game device according to an embodiment of the present invention will be described with reference to FIG. FIG. 1 is an external view of the game system 1. Hereinafter, the game apparatus and the game program of the present embodiment will be described using a stationary game apparatus as an example. In FIG. 1, the game system 1 includes a television receiver (hereinafter simply referred to as “TV”) 2, a game apparatus 3, an optical disk 4, a controller 5, and a marker unit 6. In this system, game processing is executed by the game apparatus 3 based on a game operation using the controller 5.

  An optical disc 4 that is an example of an information storage medium that can be used interchangeably with the game device 3 and that can read data is detachably inserted into the game device 3. The optical disc 4 stores a game program to be executed on the game apparatus 3. An insertion slot for the optical disk 4 is provided on the front surface of the game apparatus 3. The game apparatus 3 executes a game process by reading and executing a game program stored in the optical disc 4 inserted into the insertion slot. The game program may be stored in advance in an internal memory (preferably non-volatile but may be volatile) of the game apparatus 3, and the game apparatus 3 is connected to the game apparatus 3 via a network. The game program may be downloaded from a predetermined server (or other game device) and stored in the internal memory.

  A television 2 which is an example of a display device is connected to the game apparatus 3 via a connection cord. The television 2 displays a game image obtained as a result of the game process executed in the game device 3. In addition, a marker unit 6 is installed around the screen of the television 2 (upper side of the screen in FIG. 1). The marker unit 6 includes two markers 6R and 6L at both ends thereof. The marker 6R (same for the marker 6L) is specifically one or more infrared LEDs, and outputs infrared light toward the front of the television 2. The marker unit 6 is connected to the game apparatus 3, and the game apparatus 3 can control lighting of each infrared LED included in the marker unit 6.

  The controller 5 is an input device that provides the game device 3 with operation data indicating the content of the operation performed on the own device. The controller 5 and the game apparatus 3 are connected by wireless communication. In the present embodiment, for example, Bluetooth (registered trademark) technology is used for wireless communication between the controller 5 and the game apparatus 3. In other embodiments, the controller 5 and the game apparatus 3 may be configured to be communicable and may be connected by wire.

(Internal configuration of game device 3)
Next, the internal configuration of the game apparatus 3 will be described with reference to FIG. FIG. 2 is a block diagram showing a configuration of the game apparatus 3. The game apparatus 3 includes a CPU 10, a system LSI 11, an external main memory 12, a ROM / RTC 13, a disk drive 14, an AV-IC 15 and the like.

  The CPU 10 executes a game process by executing a game program stored on the optical disc 4, and functions as a game processor. The CPU 10 is connected to the system LSI 11. In addition to the CPU 10, an external main memory 12, a ROM / RTC 13, a disk drive 14, and an AV-IC 15 are connected to the system LSI 11. The system LSI 11 performs processing such as control of data transfer between components connected thereto, generation of an image to be displayed, and acquisition of data from an external device. The internal configuration of the system LSI 11 will be described later. The volatile external main memory 12 stores a program such as a game program read from the optical disc 4 or a game program read from the flash memory 17, or stores various data. Used as a work area and buffer area. The ROM / RTC 13 includes a ROM (so-called boot ROM) in which a program for starting the game apparatus 3 is incorporated, and a clock circuit (RTC: Real Time Clock) that counts time. The disk drive 14 reads program data, texture data, and the like from the optical disk 4 and writes the read data to an internal main memory 11e or an external main memory 12 described later.

  The system LSI 11 is provided with an input / output processor 11a, a GPU (Graphics Processor Unit) 11b, a DSP (Digital Signal Processor) 11c, a VRAM 11d, and an internal main memory 11e. Although not shown, these components 11a to 11e are connected to each other by an internal bus.

  The GPU 11b forms part of a drawing unit and generates an image according to a graphics command (drawing command) from the CPU 10. The VRAM 11d stores data (data such as polygon data and texture data) necessary for the GPU 11b to execute the graphics command. When an image is generated, the GPU 11b creates image data using data stored in the VRAM 11d.

  The DSP 11c functions as an audio processor, and generates sound data using sound data and sound waveform (tone color) data stored in the internal main memory 11e and the external main memory 12.

  The image data and audio data generated as described above are read out by the AV-IC 15. The AV-IC 15 outputs the read image data to the television 2 via the AV connector 16, and outputs the read audio data to the speaker 2 a built in the television 2. As a result, an image is displayed on the television 2 and a sound is output from the speaker 2a.

  The input / output processor (I / O processor) 11a transmits / receives data to / from components connected to the input / output processor (I / O processor) 11a or downloads data from an external device. The input / output processor 11a is connected to the flash memory 17, the wireless communication module 18, the wireless controller module 19, the expansion connector 20, and the memory card connector 21. An antenna 22 is connected to the wireless communication module 18, and an antenna 23 is connected to the wireless controller module 19.

  The input / output processor 11a is connected to the network via the wireless communication module 18 and the antenna 22, and can communicate with other game devices and various servers connected to the network. The input / output processor 11a periodically accesses the flash memory 17 to detect the presence / absence of data that needs to be transmitted to the network. If there is such data, the input / output processor 11a communicates with the network via the wireless communication module 18 and the antenna 22. Send. Further, the input / output processor 11a receives data transmitted from other game devices and data downloaded from the download server via the network, the antenna 22 and the wireless communication module 18, and receives the received data in the flash memory 17. Remember. By executing the game program, the CPU 10 reads out the data stored in the flash memory 17 and uses it in the game program. In the flash memory 17, in addition to data transmitted and received between the game apparatus 3 and other game apparatuses and various servers, save data (game result data or intermediate data) of the game played using the game apparatus 3 May be stored.

  The input / output processor 11a receives operation data transmitted from the controller 5 via the antenna 23 and the wireless controller module 19, and stores (temporarily stores) the data in the buffer area of the internal main memory 11e or the external main memory 12.

  Further, an expansion connector 20 and a memory card connector 21 are connected to the input / output processor 11a. The expansion connector 20 is a connector for an interface such as USB or SCSI, and connects a medium such as an external storage medium, a peripheral device such as another controller, or a wired communication connector. By connecting, communication with the network can be performed instead of the wireless communication module 18. The memory card connector 21 is a connector for connecting an external storage medium such as a memory card. For example, the input / output processor 11a can access an external storage medium via the expansion connector 20 or the memory card connector 21 to store data in the external storage medium or read data from the external storage medium.

  The game apparatus 3 is provided with a power button 24, a reset button 25, and an eject button 26. The power button 24 and the reset button 25 are connected to the system LSI 11. When the power button 24 is turned on, power is supplied to each component of the game apparatus 3 via an AC adapter (not shown). When the reset button 25 is pressed, the system LSI 11 restarts the boot program for the game apparatus 3. The eject button 26 is connected to the disk drive 14. When the eject button 26 is pressed, the optical disk 4 is ejected from the disk drive 14.

(Configuration of controller 5)
Next, the controller 5 will be described with reference to FIGS. 3 and 4 are perspective views showing the external configuration of the controller 5. FIG. 3 is a perspective view of the controller 5 as seen from the upper rear side, and FIG. 4 is a perspective view of the controller 5 as seen from the lower front side.

  3 and 4, the controller 5 includes a housing 31 formed by plastic molding, for example. The housing 31 has a substantially rectangular parallelepiped shape whose longitudinal direction is the front-rear direction (the Z-axis direction shown in FIG. 3), and is a size that can be gripped with one hand of an adult or a child as a whole. The player can perform a game operation by pressing a button provided on the controller 5 and moving the controller 5 itself to change its position and posture.

  The housing 31 is provided with a plurality of operation buttons. As shown in FIG. 3, a cross button 32a, a first button 32b, a second button 32c, an A button 32d, a minus button 32e, a home button 32f, a plus button 32g, and a power button 32h are provided on the upper surface of the housing 31. It is done. On the other hand, as shown in FIG. 4, a recess is formed on the lower surface of the housing 31, and a B button 32i is provided on the rear inclined surface of the recess. A function corresponding to the game program executed by the game apparatus 3 is appropriately assigned to each of the operation buttons 32a to 32i. The power button 32h is for remotely turning on / off the main body of the game apparatus 3. The home button 32 f and the power button 32 h are embedded in the upper surface of the housing 31. This can prevent the player from pressing the home button 32f or the power button 32h by mistake.

  A connector 33 is provided on the rear surface of the housing 31. The connector 33 is used to connect another device (for example, another controller) to the controller 5.

  A plurality (four in FIG. 3) of LEDs 34 a to 34 d are provided behind the upper surface of the housing 31. Here, the controller type (number) is assigned to the controller 5 to distinguish it from other controllers. The LEDs 34a to 34d are used for the purpose of notifying the player of the controller type currently set in the controller 5 and notifying the player of the remaining battery level of the controller 5. Specifically, when a game operation is performed using the controller 5, any one of the plurality of LEDs 34a to 34d is turned on according to the controller type.

  Further, the controller 5 has an imaging information calculation unit 35 (FIG. 6), and a light incident surface 35a of the imaging information calculation unit 35 is provided on the front surface of the housing 31 as shown in FIG. The light incident surface 35a is made of a material that transmits at least infrared light from the markers 6R and 6L.

  Between the first button 32b and the home button 32f on the upper surface of the housing 31, a sound release hole 31a for releasing sound from the speaker 49 (FIG. 5) built in the controller 5 is formed.

  Next, the internal structure of the controller 5 will be described with reference to FIGS. 5 and 6 are diagrams showing the internal structure of the controller 5. FIG. FIG. 5 is a perspective view showing a state in which the upper housing (a part of the housing 31) of the controller 5 is removed. FIG. 6 is a perspective view showing a state in which the lower casing (a part of the housing 31) of the controller 5 is removed. The perspective view shown in FIG. 6 is a perspective view of the substrate 30 shown in FIG.

  In FIG. 5, a substrate 30 is fixed inside the housing 31, and operation buttons 32 a to 32 h, LEDs 34 a to 34 d, an acceleration sensor 37, an antenna 45, and a speaker 49 are provided on the upper main surface of the substrate 30. Etc. are provided. These are connected to a microcomputer (microcomputer) 42 (see FIG. 6) by wiring (not shown) formed on the substrate 30 and the like. In the present embodiment, the acceleration sensor 37 is disposed at a position shifted from the center of the controller 5 with respect to the X-axis direction. This makes it easier to calculate the movement of the controller 5 when the controller 5 is rotated about the Z axis. The acceleration sensor 37 is disposed in front of the center of the controller 5 in the longitudinal direction (Z-axis direction). Further, the controller 5 functions as a wireless controller by the wireless module 44 (FIG. 7) and the antenna 45.

  On the other hand, in FIG. 6, an imaging information calculation unit 35 is provided at the front edge on the lower main surface of the substrate 30. The imaging information calculation unit 35 includes an infrared filter 38, a lens 39, an imaging element 40, and an image processing circuit 41 in order from the front of the controller 5. These members 38 to 41 are respectively attached to the lower main surface of the substrate 30.

  Further, the microcomputer 42 and the vibrator 48 are provided on the lower main surface of the substrate 30. The vibrator 48 is, for example, a vibration motor or a solenoid, and is connected to the microcomputer 42 by wiring formed on the substrate 30 or the like. The controller 48 is vibrated by the operation of the vibrator 48 according to the instruction of the microcomputer 42. As a result, a so-called vibration-compatible game in which the vibration is transmitted to the hand of the player holding the controller 5 can be realized. In the present embodiment, the vibrator 48 is disposed slightly forward of the housing 31. That is, by arranging the vibrator 48 on the end side of the center of the controller 5, the entire controller 5 can be vibrated greatly by the vibration of the vibrator 48. The connector 33 is attached to the rear edge on the lower main surface of the substrate 30. 5 and 6, the controller 5 includes a crystal resonator that generates a basic clock of the microcomputer 42, an amplifier that outputs an audio signal to the speaker 49, and the like.

  The shape of the controller 5, the shape of each operation button, the number of acceleration sensors and vibrators, and the installation positions shown in FIGS. 3 to 6 are merely examples, and other shapes, numbers, and installation positions may be used. However, the present invention can be realized. In the present embodiment, the imaging direction by the imaging unit is the positive Z-axis direction, but the imaging direction may be any direction. That is, the position of the imaging information calculation unit 35 in the controller 5 (the light incident surface 35a of the imaging information calculation unit 35) does not have to be the front surface of the housing 31, and other surfaces can be used as long as light can be taken in from the outside of the housing 31. May be provided.

  FIG. 7 is a block diagram showing the configuration of the controller 5. The controller 5 includes an operation unit 32 (operation buttons 32a to 32i), a connector 33, an imaging information calculation unit 35, a communication unit 36, and an acceleration sensor 37. The controller 5 transmits data indicating the details of the operation performed on the own device to the game apparatus 3 as operation data.

  The operation unit 32 includes the operation buttons 32a to 32i described above, and the operation button data indicating the input state (whether or not each operation button 32a to 32i is pressed) to each operation button 32a to 32i is transmitted to the microcomputer of the communication unit 36. Output to 42.

  The imaging information calculation unit 35 is a system for analyzing the image data captured by the imaging unit, determining a region with high luminance in the image, and calculating the position of the center of gravity and the size of the region. Since the imaging information calculation unit 35 has a sampling period of, for example, about 200 frames / second at the maximum, it can track and analyze even a relatively fast movement of the controller 5.

  The imaging information calculation unit 35 includes an infrared filter 38, a lens 39, an imaging element 40, and an image processing circuit 41. The infrared filter 38 passes only infrared rays from the light incident from the front of the controller 5. The lens 39 collects the infrared light transmitted through the infrared filter 38 and makes it incident on the image sensor 40. The image sensor 40 is a solid-state image sensor such as a CMOS sensor or a CCD sensor, for example, and receives the infrared light collected by the lens 39 and outputs an image signal. Here, the markers 6 </ b> R and 6 </ b> L of the marker unit 6 disposed in the vicinity of the display screen of the television 2 are configured by infrared LEDs that output infrared light toward the front of the television 2. Therefore, by providing the infrared filter 38, the image sensor 40 receives only the infrared light that has passed through the infrared filter 38 and generates image data, so that the images of the markers 6R and 6L can be captured more accurately. Hereinafter, an image captured by the image sensor 40 is referred to as a captured image. Image data generated by the image sensor 40 is processed by the image processing circuit 41. The image processing circuit 41 calculates the position of the imaging target (markers 6R and 6L) in the captured image. The image processing circuit 41 outputs coordinates indicating the calculated position to the microcomputer 42 of the communication unit 36. The coordinate data is transmitted to the game apparatus 3 as operation data by the microcomputer 42. Hereinafter, the coordinates are referred to as “marker coordinates”. Since the marker coordinates change corresponding to the orientation (posture) and position of the controller 5 itself, the game apparatus 3 can calculate the orientation and position of the controller 5 using the marker coordinates.

  The acceleration sensor 37 detects the acceleration (including gravity acceleration) of the controller 5, that is, detects the force (including gravity) applied to the controller 5. The acceleration sensor 37 detects the value of the acceleration (linear acceleration) in the linear direction along the sensing axis direction among the accelerations applied to the detection unit of the acceleration sensor 37. For example, in the case of a multi-axis acceleration sensor having two or more axes, the component acceleration along each axis is detected as the acceleration applied to the detection unit of the acceleration sensor. For example, the triaxial or biaxial acceleration sensor may be of the type available from Analog Devices, Inc. or ST Microelectronics NV. The acceleration sensor 37 is, for example, a capacitance type acceleration sensor, but other types of acceleration sensors may be used.

  In the present embodiment, the acceleration sensor 37 has a vertical direction (Y-axis direction shown in FIG. 3), a horizontal direction (X-axis direction shown in FIG. 3), and a front-back direction (Z-axis direction shown in FIG. 3) with reference to the controller 5. ) Linear acceleration is detected in each of the three axis directions. Since the acceleration sensor 37 detects acceleration in the linear direction along each axis, the output from the acceleration sensor 37 represents the linear acceleration value of each of the three axes. That is, the detected acceleration is represented as a three-dimensional vector (AX, AY, AZ) in the XYZ coordinate system set with reference to the controller 5. Hereinafter, a vector having the respective acceleration values related to the three axes detected by the acceleration sensor 37 as components is referred to as an acceleration vector.

  Data indicating the acceleration detected by the acceleration sensor 37 (acceleration data) is output to the communication unit 36. Note that the acceleration detected by the acceleration sensor 37 changes in accordance with the orientation (posture) and movement of the controller 5 itself, so the game apparatus 3 can calculate the orientation and movement of the controller 5 using the acceleration data. .

  In addition, based on the acceleration signal output from the acceleration sensor 37, a computer such as a processor (for example, the CPU 10) of the game apparatus 3 or a processor (for example, the microcomputer 42) of the controller 5 performs processing, whereby further information regarding the controller 5 is obtained. Those skilled in the art will be able to easily understand from the description of the present specification that can be estimated or calculated (determined). For example, when processing on the computer side is executed on the assumption that the controller 5 on which the acceleration sensor 37 is mounted is stationary (that is, the processing is executed assuming that the acceleration detected by the acceleration sensor is only gravitational acceleration). When the controller 5 is actually stationary, it can be determined whether or not the attitude of the controller 5 is inclined with respect to the direction of gravity based on the detected acceleration. Specifically, when the detection axis of the acceleration sensor 37 is oriented vertically downward, it can be determined whether or not it is tilted only by whether or not 1G (gravity acceleration) is applied. You can also know how much it is tilted according to its size. In the case of the multi-axis acceleration sensor 37, the degree of inclination with respect to the direction of gravity can be known in more detail by further processing the acceleration signal of each axis. In this case, the processor may calculate the tilt angle of the controller 5 based on the output from the acceleration sensor 37, or may calculate the tilt direction of the controller 5 without calculating the tilt angle. Good. In this way, by using the acceleration sensor 37 in combination with the processor, the inclination or posture of the controller 5 can be determined.

  On the other hand, when it is assumed that the controller 5 is in a dynamic state (a state in which the controller 5 is moved), the acceleration sensor 37 detects an acceleration corresponding to the movement of the controller 5 in addition to the gravitational acceleration. Therefore, the movement direction of the controller 5 can be known by removing the gravitational acceleration component from the detected acceleration by a predetermined process. Even if it is assumed that the controller 5 is in a dynamic state, the direction of gravity is obtained by removing the acceleration component corresponding to the movement of the acceleration sensor from the detected acceleration by a predetermined process. It is possible to know the inclination of the controller 5 with respect to. In another embodiment, the acceleration sensor 37 is a built-in process for performing a predetermined process on the acceleration signal before outputting the acceleration signal detected by the built-in acceleration detection means to the microcomputer 42. An apparatus or other type of dedicated processing apparatus may be provided. A built-in or dedicated processing device converts the acceleration signal into a tilt angle (or other preferred parameter) if, for example, the acceleration sensor 37 is used to detect static acceleration (eg, gravitational acceleration). It may be a thing.

  The communication unit 36 includes a microcomputer 42, a memory 43, a wireless module 44, and an antenna 45. The microcomputer 42 controls the wireless module 44 that wirelessly transmits data acquired by the microcomputer 42 to the game apparatus 3 while using the memory 43 as a storage area when performing processing.

  Each data (operation button data, marker coordinate data, and acceleration data) output from the operation unit 32, the imaging information calculation unit 35, and the acceleration sensor 37 to the microcomputer 42 is temporarily stored in the memory 43. Each of these data is transmitted to the game apparatus 3 as the operation data. That is, the microcomputer 42 outputs the operation data stored in the memory 43 to the wireless module 44 when the transmission timing to the wireless controller module 19 of the game apparatus 3 arrives. The wireless module 44 modulates a carrier wave of a predetermined frequency with operation data using, for example, Bluetooth (registered trademark) technology, and radiates a weak radio signal from the antenna 45. That is, the operation data is converted into a weak radio signal by the wireless module 44 and transmitted from the controller 5. The weak radio signal is received by the wireless controller module 19 on the game apparatus 3 side. By demodulating and decoding the received weak radio signal, the game apparatus 3 can acquire operation data. And CPU10 of the game device 3 performs a game process based on the acquired operation data and a game program. Note that the wireless transmission from the communication unit 36 to the wireless controller module 19 is sequentially performed at predetermined intervals, but the game processing is generally performed in units of 1/60 seconds (one frame time). Therefore, it is preferable to perform transmission at a period equal to or shorter than this time. The communication unit 36 of the controller 5 outputs each operation data to the wireless controller module 19 of the game apparatus 3 at a rate of once every 1/200 seconds, for example.

  By using the controller 5, in addition to the conventional general game operation of pressing each operation button, the player designates an arbitrary position on the screen by the controller 5 and moves the controller 5 itself. It can be performed. For example, the player can perform a game operation for moving the controller 5 and a game operation for pointing the position on the screen of the television 2 using the controller 5.

(Outline of processing in game device)
Hereinafter, an outline of processing executed by the game apparatus 3 will be described. Hereinafter, game processing in a game in which a player plays by operating a player character in a virtual three-dimensional space will be described.

  FIG. 8 is a diagram showing an example of the game screen of the game in the present embodiment. As shown in FIG. 8, a ground object 51 and a wall object 52 are arranged in a virtual three-dimensional space (game space) in this game. The ground object 51 and the wall object 52 are terrain objects that are fixedly arranged in the game space. Note that an xyz coordinate system (world coordinate system) for representing a position in the game space is defined. Here, the ground object 51 is arranged in parallel to the xz plane. The wall object 52 is disposed in parallel to the xy plane. In FIG. 8, xyz coordinate axes are shown to indicate directions in a three-dimensional space, but actually no coordinate axes are displayed.

  Furthermore, a player object 53 that is an operation target of the player appears in the game space. The player object 53 can move, jump, and fly in the game space according to an operation input to the controller 5. Therefore, the player object 53 may float away from the ground object 51 and the wall object 52 by jumping or flying.

  In the game according to this embodiment, the direction of gravity is defined in the game space. In other words, the game apparatus 3 calculates an action such as a jump by the player object 53 and the behavior of another object in consideration of virtual gravity. In the present embodiment, the direction of gravity is not always constant, and changes according to the game situation. For example, when the player object 53 passes a certain point in the game space, the direction of gravity changes by 90 °, and it becomes possible to walk on a place that was a wall before the change, or the ground before the change becomes a wall. . In the present embodiment, the direction of gravity may vary depending on the position in the game space. For example, the ground object 51 may be a large sphere such as a star, and at this time, the direction of gravity on the ground (the surface of the sphere) may be set to face the center of the sphere.

  In the game described above, the player operates the player object 53 in the three-dimensional space using the controller 5 to achieve a predetermined task such as reaching the goal point or defeating a specific enemy. The game progresses for the purpose.

  In a game in which the player object 53 moves in the three-dimensional space as described above, when the player object 53 is in a state of floating in the air, for example, during a jump or flight, the player has a player object 53 in the three-dimensional space. Difficult to grasp the position of That is, in the state of floating in the air, it is difficult to understand the position of the player object 53 on the xz plane and the position of the player object 53 on the xy plane. If the exact position of the player object 53 cannot be grasped, the player cannot determine how to operate the player object 53, so there is a possibility that the player object 53 cannot be accurately operated.

  Therefore, in the present embodiment, the game apparatus 3 draws the shadow of the player object 53 in two directions so that the player can easily grasp the position of the player object 53 in the three-dimensional space. Specifically, as shown in FIG. 8, a first shadow 54 and a second shadow 55 are drawn in the game space.

  The first shadow 54 is drawn at a position obtained by projecting the position of the player object 53 with respect to the ground object 51 in the direction of gravity. From the position of the first shadow 54 on the ground object 51, the player can intuitively grasp the position of the player object 53 on the xz plane perpendicular to the direction of gravity. Furthermore, the player can intuitively grasp the distance from the ground object 51 to the player object 53 based on the distance between the first shadow 54 and the player object 53.

  The second shadow 55 is drawn at a position obtained by projecting the position of the player object 53 with respect to the wall object 52 in a direction perpendicular to the direction of gravity. Here, the direction in which the second shadow 55 is projected, that is, the direction in which the player object is projected in order to draw the second shadow 55 is referred to as a “projection direction”. In FIG. 8, it is assumed that the projection direction is the z-axis positive direction. From the position of the second shadow 55 on the wall object 52, the player can intuitively grasp the position of the player object 53 on the xy plane perpendicular to the projection direction. Furthermore, the player can intuitively grasp the distance from the wall object 52 to the player object 53 based on the distance between the second shadow 55 and the player object 53.

  As described above, according to the present embodiment, the game apparatus 3 draws two shadows projected in two different directions as the shadow of the player object. As a result, the player can intuitively understand the three-dimensional position of the player object in the three-dimensional space. Note that by making the direction in which the two shadows are projected substantially perpendicular, it is easier for the player to recognize the position of the object in the three-dimensional space than in the case where the directions in which the two shadows are projected are close.

  In the present embodiment, the game apparatus 3 does not always draw two shadows, but draws two shadows only when the player object 53 is located within a preset shadow drawing area in the game space. When the player object 53 is located outside the shadow drawing area, only the first shadow is drawn. The shadow drawing area is set to a place where a terrain object (for example, the wall object 52 shown in FIG. 8) serving as a projection plane on which the second shadow is projected exists. Referring to FIG. 8 as an example, a shadow drawing area is set in front of the wall object 52, and no shadow drawing area is set behind or on the side of the wall object 52. Further, the shadow drawing area may be set to a place where it is assumed that the position in the three-dimensional space is particularly difficult to grasp, for example, when the player object 53 is floating in the air. For example, when the player object 53 can fly in the sky only when a predetermined condition (item acquisition) is satisfied, a shadow drawing area is set near a place where the predetermined condition can be satisfied (near the place where the item is present). It may be set. As described above, by setting a shadow drawing area in the game space, when the second shadow is unnecessary, the process of drawing the second shadow can be omitted. Can be reduced. For example, it is assumed that there is no object to be a projection plane on which the shadow is projected, and thus the process of drawing the shadow is useless, or it is easy to grasp the position of the player object 53 without the second shadow. In such a case, the processing load of the game apparatus 3 can be reduced by omitting the process of drawing the second shadow.

  In the present embodiment, the first shadow and the second shadow are drawn so that their display forms are different from each other. Specifically, the first shadow has a shape obtained by projecting the shape of the player object 53 onto the ground object 51, whereas the second shadow has a circular shape (or an oval shape). The shape is different. Thus, by changing the display form of the two shadows, the player can distinguish and recognize the two shadows. Thus, the player can clearly recognize the direction of gravity (the direction in which the first shadow is projected). For a game in which the direction of gravity changes according to the game situation, such as this game, it is particularly effective to make the direction of gravity easy to understand by making the two shadow display forms different.

(Details of game processing)
Hereinafter, the game process in the present embodiment will be described in detail with reference to FIGS. FIG. 9 is a diagram showing main data stored in the main memory (external main memory 12 or internal main memory 11e) of the game apparatus 3. As shown in FIG. As shown in FIG. 9, the main memory stores a game program 60, operation data 61, game processing data 62, and the like. In addition to the data shown in FIG. 9, the main memory stores data necessary for game processing, such as image data of various objects appearing in the game and data indicating various parameters of the objects.

  The game program 60 is an example of an image processing program according to the present embodiment, and a part or all of the game program 60 is read from the optical disc 4 and stored in the main memory at an appropriate timing after the game apparatus 3 is turned on. The

  The operation data 61 is operation data transmitted from the controller 5 to the game apparatus 3. The operation data 61 includes operation button data indicating input states for the operation buttons 32 a to 32 i, marker coordinate data indicating marker coordinates calculated by the imaging information calculation unit 35, and an acceleration vector detected by the acceleration sensor 37. Is included. As described above, since the operation data is transmitted from the controller 5 to the game apparatus 3 at a rate of once every 1/200 seconds, the operation data stored in the main memory is updated at this rate. Only the latest (last acquired) operation data may be stored in the main memory.

  The game process data 62 is data used in a game process (FIG. 12) described later. The game processing data 62 includes current area data 63, object position data 64, gravity direction data 65, first intersection position data 66, second intersection position data 67, first shadow image data 68, and second shadow image data 69. including.

  The current area data 63 is data including shadow drawing area data related to the shadow drawing area set in the field where the player object currently exists. Here, the field is one game space composed of terrain objects and the like, and in this game, a plurality of game spaces (fields) are prepared. The shadow drawing area data is data indicating various types of information related to the shadow drawing area.

  FIG. 10 is a diagram illustrating an example of current area data. As shown in FIG. 10, the shadow drawing area data included in the current area data is data indicating each information of area ID, field ID, area position, area size, projection direction, and maximum distance regarding one shadow drawing area. is there. Note that the current area data shown in FIG. 10 includes shadow drawing area data related to the shadow drawing area set in the field whose field ID is “001”. In the present embodiment, shadow drawing area data regarding each shadow drawing area set in each field is stored in the optical disc 4. When the field in which the player object exists is changed, the shadow drawing area data relating to the shadow drawing area set in the changed field is read from the optical disc 4 and stored as new current area data 63 in the main memory. Hereinafter, each piece of information indicated by the shadow drawing area data will be described.

  The area ID is a number for identifying the shadow drawing area, and is a number unique to the shadow drawing area. The field ID is a number for identifying the field in which the shadow drawing area exists, and is a number unique to the field.

  FIG. 11 is a diagram illustrating an example of a shadow drawing area set in the game space. FIG. 11 shows a part of the game space. In FIG. 11, a shadow drawing area 71 (a region indicated by a thick dotted line in FIG. 11) is set in front of the wall object 52. As shown in FIG. 11, in this embodiment, the shadow drawing area is a rectangular parallelepiped area, and each side is set to be parallel to any of the x-axis, y-axis, and z-axis.

  The area position is a position where the shadow drawing area is set, and in this embodiment, is the center position P (see FIG. 11) of the shadow drawing area which is a rectangular parallelepiped. Specifically, the area position is represented by coordinate values in the world coordinate system. For example, in FIG. 11, the coordinate value “(350, 550, 250)” is associated with the shadow drawing area whose area ID is “001”. The area size is the size of the shadow drawing area. Specifically, the area size represents a length that is ½ of the length of each of the three sides of the shadow drawing area that is a rectangular parallelepiped. That is, the shadow drawing area is specified as an area having a width of the length indicated by the area size with the coordinate value indicated by the area position as the center. For example, in FIG. 11, three values “(500, 800, 500)” are associated with the shadow drawing area whose area ID is “001”. Therefore, the shadow drawing area whose area ID is “001” is an area having a width of 500 in the x-axis direction, 800 in the y-axis direction, and 500 in the z-axis direction centering on “(350, 550, 250)”. That is, the region is represented by “−150 ≦ x ≦ 850, −250 ≦ y ≦ 1350, −250 ≦ z ≦ 750”. The range of the shadow drawing area in the game space is specified by the area position and area size information.

  The projection direction is a direction in which the second shadow is projected in the shadow drawing area. Specifically, this projection direction is represented as a vector (vector V shown in FIG. 11) indicating the direction in the game space. In the present embodiment, the vector is represented as a unit vector. For example, when the projection direction is the direction of the vector V shown in FIG. 11, the projection direction is expressed as a negative z-axis direction, that is, (0, 0, −1). Also, as shown in FIG. 10, in this embodiment, since the projection direction is individually set for each shadow drawing area, the game developer can freely set the direction in which the second shadow is projected for each shadow drawing area. Can be set.

  The maximum distance is the maximum distance at which the second shadow is projected. That is, when an object (for example, a wall object) that draws the second shadow exists within the range from the player object to the maximum distance in the projection direction, the second shadow is drawn.

  Returning to the description of FIG. 9, the object position data 64 indicates the position of the player object in the game space. Specifically, the position is represented by coordinate values in the world coordinate system. The position of the player object is set to a position of a predetermined part of the player object (for example, the position of the center of the body). Note that the game apparatus 3 may appropriately change the position of the player object in consideration of the operability of the player. For example, when the outer shape of the player object is deformed, the position of the player object may be changed as appropriate according to the outer shape. More specifically, for example, when the player object jumps while rolling the body, the outer shape of the player object is close to a sphere. In this case, the object position data 64 may be set with the position near the center of the sphere as the position of the player object.

  The gravity direction data 65 indicates the (virtual) direction of gravity applied to the player object at the current time. The direction of gravity is expressed as a unit vector indicating the direction in the game space, like the projection direction. In the present embodiment, since the first shadow is drawn at a position where the player object is projected in the direction of gravity, the direction of gravity is the direction in which the first shadow is projected.

  The first intersection position data 66 indicates the position of the first shadow, that is, the position of the intersection between the straight line extending from the player object in the direction of gravity and the terrain object. The second intersection position data 67 indicates the position of the second shadow, that is, the position of the intersection between the straight line extending from the player object in the projection direction and the terrain object.

  The first shadow image data 68 is first shadow image data. In the present embodiment, the first shadow is a shape obtained by projecting the outer shape of the player object in the direction of gravity, and has a predetermined color (for example, black). The second shadow image data 69 is second shadow image data. In the present embodiment, the second shadow has a predetermined shape and is a color (darkness) determined based on the distance from the player object to the second shadow. A method for drawing the first shadow image and the second shadow image will be described later.

  Next, details of processing performed in the game apparatus 3 will be described with reference to FIGS. FIG. 12 is a main flowchart showing the flow of processing executed in the game apparatus 3. When the power of the game apparatus 3 is turned on, the CPU 10 of the game apparatus 3 executes a startup program stored in a boot ROM (not shown), whereby each unit such as the main memory is initialized. Then, the game program stored in the optical disc 4 is read into the main memory, and the CPU 10 starts executing the game program. The flowchart shown in FIG. 12 is a flowchart showing processing performed after the above processing is completed. Note that the game processing shown in FIG. 12 is performed as a cooperative operation of the CPU 10 and the GPU 11b. In the following, the game process will be described focusing on the process of generating and displaying the shadow of the player object.

  First, in step S1, the CPU 10 executes an initialization process relating to the game. Specifically, the CPU 10 reads from the optical disc 4 game character data such as a player object and terrain object data for constructing a predetermined field (a field in which the player object is located at the start of the game). . Then, the read data is used to construct a three-dimensional space of the field, and processing such as placing a player object or another object at the initial position of the field is executed. In step S 1, shadow drawing area data relating to the shadow drawing area set in the field is read from the optical disc 4 and stored in the main memory as current area data 63.

  After step S1, the processing loop of steps S2 to S14 is repeatedly executed while the game is executed. Note that one processing loop is executed once per frame time (for example, 1/60 seconds).

  In step S2, the CPU 10 acquires operation data. That is, the operation data transmitted from the controller 5 is received by the game apparatus 3 and stored in the main memory, so the CPU 10 reads the operation data 61 from the main memory. After step S2, the process of step S3 is executed.

  In step S3, the CPU 10 determines whether or not the field in which the player object exists has been changed. Here, in this game, the field is changed when a predetermined game condition is satisfied. A predetermined game condition is satisfied when, for example, a player object enters an entrance for moving to another field, a predetermined enemy object existing in the field is defeated, a player object Is a case where a predetermined item is acquired. If the determination result of step S3 is affirmative, the processes of steps S4 and S5 are executed. On the other hand, when the determination result of step S3 is negative, the processes of steps S4 and S5 are skipped, and the process of step S6 described later is executed.

  In step S <b> 4, the CPU 10 reads shadow drawing area data related to the shadow drawing area set in the new field after the change from the optical disc 4. The read one or more shadow drawing area data is stored in the main memory as current area data 63. In step S <b> 4, the CPU 10 reads from the optical disk 4 terrain object data and the like for constructing a new field after the change.

  In step S5 subsequent to step S4, the CPU 10 constructs a new field after the change using the terrain object data read in step S4. In step S5, each object (including a player object and an enemy object) appearing in the new field is placed at a predetermined position. After step S5, the process of step S6 is executed.

  In step S6, the CPU 10 operates the object on the field. That is, the player object is moved according to the player's operation on the controller 5, or the enemy object is moved according to a predetermined algorithm. Specifically, the action of the player object is determined based on the operation data acquired in step S2. At this time, the position of the player object in the game space is calculated, and data indicating the position is stored as object position data 64 in the main memory. After step S6, the process of step S7 is executed.

  In step S7, the CPU 10 calculates the direction of virtual gravity applied to the player object. In this embodiment, the direction of gravity is determined based on the game situation. For example, the direction of gravity is determined based on the current position of the player object. That is, the correspondence between each position in the game space and the direction of gravity at that position is predetermined, and data indicating the correspondence is stored in the optical disc 4. The CPU 10 refers to the data indicating the correspondence and specifies the gravity direction corresponding to the current position of the player object. Note that the current position of the player object is indicated by object position data 64 stored in the main memory. Further, for example, the direction of gravity changes when the player object passes a certain point in the game space, or a predetermined game condition (for example, obtaining an item with the player object) is satisfied. It may be determined to change in some cases. Data indicating the gravity direction calculated in step S7 is stored in the main memory as gravity direction data 65.

  In step S8 subsequent to step S7, the CPU 10 executes a first shadow drawing process. The first shadow drawing process is a process for drawing a first shadow that is a shadow projected in the direction of gravity. The details of the first shadow drawing process will be described below with reference to FIG.

  FIG. 13 is a flowchart showing the flow of the first shadow drawing process (step S8) shown in FIG. In the first shadow drawing process, first, in step S21, the CPU 10 calculates a straight line that faces the direction of gravity from the position of the player object. That is, referring to the object position data 64 and the gravity direction data 65 stored in the main memory, a straight line (half line) extending in the direction indicated by the gravity direction data 65 is calculated from the coordinates indicated by the object position data 64. . After step S21, the process of step S22 is executed.

  In step S22, the CPU 10 determines whether or not there is a terrain object that contacts the straight line calculated in step S21. That is, it is determined whether there are polygons that make up the terrain object that touch the straight line. If the determination result of step S22 is affirmative, the processes of steps S23 to S25 are executed. On the other hand, when the determination result of step S22 is negative, the CPU 10 skips the processes of steps S23 to S25 and ends the first shadow drawing process.

  In step S23, the CPU 10 calculates the position of the intersection of the straight line calculated in step S21 and the terrain object in contact therewith. In step S23, the position at which the first shadow is projected is calculated. Data indicating the calculated position of the intersection is stored in the main memory as first intersection position data 66.

  In steps S24 and S25 executed after step S23, a game image in which a first shadow is added to the terrain object is generated. Here, any method may be used to add a shadow to an object in the game space, but in this embodiment, a shadow is applied using a texture. Details of the processes in steps S24 and S25 will be described below.

  In step S24, the CPU 10 generates a first shadow image. The image of the first shadow can be generated by determining the shape and color of the first shadow (specifically, the darkness of black). The shape of the first shadow is calculated so as to be a shape in which the player object is projected onto the projection plane (terrain object) in the direction of gravity. That is, the shape of the first shadow is the outer shape when the player object is viewed from the direction of gravity. In the present embodiment, the color of the first shadow is determined in advance. The first shadow image data generated in step S24 is stored in the main memory as first shadow image data 68.

  In another embodiment, in step S24, the CPU 10 changes the first shadow display form based on the distance from the player object to the position where the shadow is added (the position of the intersection calculated in step S23). It may be changed. For example, the longer the distance, the larger the size of the first shadow, or the longer the distance, the lighter the color of the first shadow may be. According to this, since it becomes easier for the player to understand the distance, it becomes easier to grasp the position of the player object in the three-dimensional space.

  In step S25, the CPU 10 draws the first shadow at the position of the intersection calculated in step S23. That is, the first shadow image is overlaid and drawn at the position of the intersection of the terrain object. Specifically, first, for the terrain object, the CPU 10 draws an object (such as a terrain object and a player object) in the game space using a predetermined texture for the terrain object. Next, a terrain object is drawn using the first shadow image generated in step S24 as a texture, and is superimposed on the initially drawn image to obtain a shadowed image. After step S25, the CPU 10 ends the first shadow drawing process.

  In step S25, the game apparatus 3 draws the terrain object using the texture for the terrain object, and then draws the terrain object using the shadow image as the texture. Here, the process for adding a shadow to the terrain object may be any process, and is not limited to the method in the game process. For example, in another embodiment, in order to add a shadow to a terrain object, the game apparatus 3 performs a process of combining a texture for the terrain object and a shadow image, and uses the combined texture to generate a terrain object. You may make it draw. Further, the method is not limited to using a shadow image as a texture, and a shadow polygon may be placed on the terrain object by placing a shadow polygon on the terrain object.

  In the first shadow drawing process described above, the first shadow is always displayed regardless of whether or not the player object exists in the shadow drawing area. The first shadow is a shape obtained by projecting the shape of the player object onto the terrain object that is the projection plane. That is, the first shadow is displayed for the purpose of more naturally expressing the game space in addition to the purpose of identifying the position of the player object in the three-dimensional space.

  Returning to the description of FIG. 12, in step S <b> 9 subsequent to step S <b> 8, the CPU 10 performs the second shadow drawing process for all of the shadow drawing areas set in the current field (the field in which the player object currently exists). It is determined whether or not (Step S11 described later) has been executed. If the determination result of step S9 is affirmative, the process of step S12 described later is executed. On the other hand, if the determination result of step S9 is negative, that is, if there is a shadow drawing area for which the second shadow drawing process has not yet been executed, the process of step S10 is executed.

  In step S10, the CPU 10 determines whether or not the second shadow has already been drawn in the current processing loop of steps S2 to S12. If the determination result of step S10 is affirmative, the process of step S12 described later is executed. On the other hand, when the determination result of step S10 is negative, that is, when the second shadow is not yet drawn, the process of step S11 is executed.

  In step S11, the CPU 10 executes a second shadow drawing process. The second shadow drawing process is a process for drawing a second shadow that is a shadow projected in the projection direction. Hereinafter, the details of the second shadow rendering process will be described with reference to FIG.

  FIG. 14 is a flowchart showing the flow of the second shadow drawing process (step S11) shown in FIG. In the second shadow drawing process, first, in step S31, the CPU 10 selects a shadow drawing area for which the second shadow drawing process has not yet been executed from among the shadow drawing areas set in the current field. After step S31, the process of step S32 is executed.

In step S32, the CPU 10 determines whether or not a player object exists in the shadow drawing area selected in step S31. The determination in step S32 is performed by referring to the shadow drawing area data related to the shadow drawing area selected in step S31 and the object position data 64 among the shadow drawing area data included in the current area data 63. Specifically, the determination in step S32 is performed based on whether or not the coordinate values (px, py, pz) indicated by the object position data 64 satisfy the following expression (1).
ax−sx ≦ px ≦ ax + sx and ay−sy ≦ py ≦ ay + sy and az−sz ≦ pz ≦ az + sz (1)
In the above equation (1), the area position indicated by the shadow drawing area data related to the shadow drawing area selected in step S31 is (ax, ay, az), and the area size is (sx, sy, sz). If the determination result of step S32 is affirmative, the process of step S33 is executed. On the other hand, when the determination result of step S32 is negative, the CPU 10 ends the second shadow drawing process. In the second shadow drawing process in this case, the second shadow is not drawn.

  In step S33, the CPU 10 calculates a straight line that faces the projection direction from the position of the player object. This straight line is calculated using the shadow drawing area data relating to the shadow drawing area selected in step S31 and the object position data 64. Specifically, the CPU 10 calculates a straight line (half straight line) extending in the projection direction indicated by the shadow drawing area data from the coordinates indicated by the object position data 64. After step S33, the process of step S34 is executed.

  In step S34, the CPU 10 determines whether or not there is a terrain object in contact with the straight line calculated in step S33 within a range within the maximum distance from the position of the player object. That is, it is determined whether or not there are polygons that make up the terrain object that touch the straight line within the above range. The maximum distance is the maximum distance indicated by the shadow drawing area data regarding the shadow drawing area selected in step S31. When the determination result of step S34 is affirmative, the processes of steps S35 to S38 are executed. On the other hand, if the determination result of step S34 is negative, the CPU 10 skips the processes of steps S35 to S38 and ends the second shadow drawing process. In the second shadow drawing process in this case, the second shadow is not drawn.

  In step S35, the CPU 10 calculates the position of the intersection of the straight line calculated in step S34 and the terrain object in contact therewith. When there are a plurality of terrain objects in contact with the straight line within the maximum distance, the position of the intersection with the terrain object with the shortest distance is calculated. In step S35, the position where the second shadow is projected is calculated. Data indicating the calculated position of the intersection is stored in the main memory as second intersection position data 67. After step S35, the process of step S36 is executed.

In step S36, the CPU 10 calculates the color intensity of the second shadow. This darkness is calculated based on the distance from the position of the player object to the intersection calculated in step S35. In the present embodiment, the second shadow is a circular shape having a predetermined size, and the density of the second shadow is expressed as the number N of black pixels in the circle. Specifically, the number N of black pixels is calculated according to the following equation (2).
N = Dmax− (Dmax−Dmin) × Dis / Dismax (2)
In the above equation (2), the variable Dis is the distance from the position of the player object to the intersection point. The constant Dismax, the constant Dmax, and the constant Dmin are determined in advance. The constant Dmax is the number of black pixels when the distance is 0, and the constant Dmin is the number of black pixels when the distance is equal to or greater than the constant Dismax. By calculating the pixel number N according to the above equation (2), the pixel number N increases as the distance decreases, and the pixel number N decreases as the distance increases. That is, the smaller the distance, the darker the color of the second shadow, and the larger the distance, the lighter the color of the second shadow. Therefore, according to the present embodiment, the player can intuitively understand the distance from the player object to the terrain object on which the second shadow is projected according to the darkness of the second shadow. It becomes easier to grasp the position of the player object.

  In step S36, the CPU 10 changes the display form of the second shadow by changing the color intensity of the second shadow based on the distance, but in other embodiments, The size of the second shadow may be changed based on the distance. For example, the longer the distance, the larger the first shadow may be. Moreover, you may make it change both the magnitude | size and darkness of a 2nd shadow based on the said distance.

  In step S37 subsequent to step S36, the CPU 10 generates a second shadow image. Specifically, an image is generated in which black pixels exist in the substantially circular pixel region having a predetermined size by the number N of pixels calculated in step S36. In the generated image, the color of pixels other than black pixels is transparent. The image data of the second shadow generated in step S37 is stored in the main memory as the second shadow image data 69.

  In step S38 following step S37, the CPU 10 draws the second shadow at the position of the intersection calculated in step S35. That is, the second shadow image is superimposed and drawn at the position of the intersection of the terrain object. Specifically, the CPU 10 synthesizes a predetermined texture for the terrain object and the second shadow image so that the second shadow is added to the position of the intersection of the terrain object (overlapping). Match). After step S38, the CPU 10 ends the second shadow drawing process.

  In the second shadow drawing process described above, the second shadow is displayed only when the player object exists in the shadow drawing area. Further, the second shadow has a predetermined shape regardless of the shape in which the shape of the player object is projected onto the terrain object that is the projection plane. Since the second shadow is displayed for the purpose of identifying the position of the player object in the three-dimensional space, the first shadow has a shape different from the first shadow rather than a realistic shape. This is because it is preferable to make the shape easy to distinguish from the shadow. Moreover, by setting it as a predetermined shape, the processing load of the game apparatus 3 can be reduced as compared with the case where the shape of the object is projected onto the projection plane.

  Returning to the description of FIG. 12, in step S12, the CPU 10 displays a game image. That is, the CPU 10 generates an image when the game space is viewed from a virtual camera set in the game space, and displays the image on the screen of the television 2. At this time, for the ground object at the position of each intersection calculated in step S23 (or steps S23 and S35), the ground object is drawn using the texture in which the shadow image is superimposed on the texture for the ground object. Then, a game image in which a shadow is added to the position of the intersection is generated.

  In step S13 following step S12, the CPU 10 determines whether or not to end the game. The determination in step S13 is made based on, for example, whether or not the game is cleared, whether or not the game is over, and whether or not the player gives an instruction to stop the game. If the determination result of step S13 is negative, the process of step S2 is executed again. Thereafter, the processes in steps S2 to S13 are repeatedly executed until it is determined in step S13 that the game is to be ended. On the other hand, if the determination result of step S13 is affirmative, the CPU 10 ends the game process shown in FIG. This is the end of the description of the game process.

  As described above, according to the above game processing, when the player object exists in the shadow drawing area, the first shadow is displayed at a position facing the gravity direction from the player object, and the player object (from the gravity direction) A second shadow is displayed at a position facing the projection direction (see FIG. 8). Thus, the player can intuitively understand the position of the player object in the three-dimensional space.

  In the game process, the position of the intersection between the straight line and the terrain object in contact with the straight line is calculated in steps S23 and S35. Here, in other embodiments, not only the terrain object, but also the position of the intersection of the straight line and the object in contact with the straight line at the position closest to the player object may be calculated. Then, a shadow may be added to the calculated position of the intersection.

  Further, in the above game process, in order to make the game space appear more natural, shadows of objects other than the player object (for example, the wall object 52) may be displayed. For example, the game apparatus 3 may execute a step of drawing a shadow on the other object at a timing after step S6. In addition, this step may be executed by generating a first shadow for other objects in the first shadow drawing process (step S8). The shadow of the other object may be generated by a method different from the first and second shadows, and the shadow generation method may be different from the first and second shadow generation methods. However, the direction in which the shadow is projected may be different from the direction in which the first and second shadows are projected. However, like the first shadow of the player object, it is preferable that the shadow of the other object is cast at a position facing the gravity direction from the object. Even when a shadow is added to another object, it is not necessary to add a second shadow to the other object. That is, the second shadow may be attached only to a predetermined object (a player object in the above embodiment). In this way, with regard to the player object, priority is given to the player grasping the position, and two shadows are drawn in two directions, and with respect to other objects, priority is given to expressing the game world naturally. One shadow may be drawn in the direction.

  In the above game process, the object for generating two shadows has been described as a player object. However, in other embodiments, two shadows are generated for one or more predetermined objects. It may be. For example, in addition to the player object (or instead of the player object), the first and second shadows may be generated and displayed for the enemy object. Further, even when the first and second shadows are generated for a plurality of objects, the second shadow may not be generated for other objects than the plurality of objects.

  As described above, the present invention can be used as, for example, a game program or a game device for the purpose of making a player intuitively recognize the position of an object in a virtual three-dimensional space.

External view of game system 1 Functional block diagram of game device 3 The perspective view which shows the external appearance structure of the controller 5 The perspective view which shows the external appearance structure of the controller 5 The figure which shows the internal structure of the controller 5 The figure which shows the internal structure of the controller 5 Block diagram showing the configuration of the controller 5 The figure which shows an example of the game screen of the game in this embodiment The figure which shows the main data memorize | stored in the main memory of the game device 3 Diagram showing an example of current area data The figure which shows an example of the shadow drawing area set in game space Main flowchart showing a flow of processing executed in the game apparatus 3 The flowchart which shows the flow of the 1st shadow drawing process (step S8) shown in FIG. The flowchart which shows the flow of the 2nd shadow drawing process (step S11) shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Game system 2 Television 3 Game device 4 Optical disk 5 Controller 6 Marker part 10 CPU
11c GPU
11e Internal main memory 12 External main memory 51 Ground object 52 Wall object 53 Player object 54 First shadow 55 Second shadow 71 Shadow drawing area

Claims (13)

A game program to be executed by a computer of a game device that displays an object existing in a virtual three-dimensional space on a display device,
A first position calculating step of calculating a position of an intersection of a straight line passing through the position of the object and facing a predetermined first direction and a predetermined other object as a first position;
A first shadow drawing step of drawing a shadow of the object at the first position;
A second position calculating step of calculating a position of an intersection of a straight line passing through the position of the object and facing a second direction not parallel to the first direction and a predetermined other object as a second position;
A game program for causing the computer to execute a second shadow drawing step of drawing a shadow of the object at the second position. A predetermined shadow drawing area is set in the three-dimensional space,
Causing the computer to further execute an area determination step for determining whether or not the object exists in a predetermined shadow drawing area set in the three-dimensional space;
The game program according to claim 1, wherein the second shadow drawing step is executed only when it is determined in the area determination step that the position of the object exists within the shadow drawing area. The storage means of the game device stores shadow drawing area data in which a projection direction is associated with each of the shadow drawing areas.
3. The second position calculating step, wherein the computer calculates the second position using a projection direction associated with a shadow drawing area where the object exists in the shadow drawing area data as the second direction. The game program described in.   The game program according to claim 1, wherein the first direction is a gravity direction set in the three-dimensional space.   The game program according to claim 4, further causing the computer to execute a gravity direction changing step of changing the gravity direction according to a game situation.   6. The game program according to claim 2, wherein in the second shadow drawing step, the computer draws a shadow so as to have a display form different from the shadow drawn in the first shadow drawing step. In the second position calculating step, the computer calculates the second position only for a predetermined object.
In the second shadow drawing step, the computer draws a shadow only for the predetermined object,
A third position calculating step of calculating, as a third position, a position of an intersection of a straight line facing a third direction not parallel to the second direction and another object other than the predetermined object;
The game program according to claim 1, further causing the computer to execute a third shadow drawing step of drawing a shadow of an object other than the predetermined object at the third position.   The game program according to claim 1, wherein the predetermined object is a terrain object fixedly arranged in the three-dimensional space.   3. The game program according to claim 1, wherein in the first shadow drawing step, the computer changes the darkness of the shadow based on a distance from the position of the object to the first position.   3. The game program according to claim 1, wherein in the second shadow drawing step, the computer changes the density of the shadow based on a distance from the position of the object to the second position.   The game program according to claim 1, wherein in the first shadow drawing step, the computer changes the size of the shadow based on a distance from the position of the object to the first position.   The game program according to claim 1 or 2, wherein, in the second shadow drawing step, the computer changes a size of the shadow based on a distance from the position of the object to the second position. A game device that causes a display device to display an object existing in a virtual three-dimensional space,
First position calculation means for calculating, as a first position, the position of the intersection of a straight line that faces a predetermined first direction from the position of the object and a predetermined other object;
First shadow drawing means for drawing a shadow of the object at the first position;
Second position calculating means for calculating, as a second position, a position of an intersection of a straight line facing a second direction not parallel to the first direction from the position of the object and a predetermined other object;
A game device comprising: second shadow drawing means for drawing a shadow of the object at the second position.

Images