JP2008027050A - Image generating apparatus, image generating method, and program - Google Patents

Abstract

An image in which an object is viewed from all directions in a virtual space is generated.
In an image generation apparatus, a storage unit stores information on a plane object, a three-dimensional object, a light source, a viewpoint, and a line-of-sight direction in a virtual space. The calculation unit 301 calculates the shape and position of the shadow of the three-dimensional object projected onto the plane object by the light from the light source. The determination unit 303 determines whether the viewpoint is on the same side or a different side from the plane object. If they are on the same side, the generation unit 304 generates an image including a plane object, a solid object, and its shadow. If they are on different sides, the generation unit 304 generates an image including the solid object and its shadow.
[Selection] Figure 3

Description

  The present invention relates to an image generation apparatus, an image generation method, and a program suitable for generating an image that can be seen from all directions in a virtual space.

Conventionally, three-dimensional graphics techniques have been used in the field of computer graphics and processing in various game devices. In such 3D graphics technology, an object to be drawn is arranged in a virtual 3D space. The surface of the object is represented by a polyhedron, and the angular surface of the polyhedron is a polygon. Such 3D graphics techniques are disclosed in the following documents.
Japanese Patent No. 3490983

  According to the conventional technology such as Patent Document 1, for example, an object placed on the ground in a virtual space is irradiated with light from a light source in the virtual space, and an image viewed from a viewpoint in the virtual space is obtained. Can be generated. However, if the position of the viewpoint in the virtual space moves below the ground, the back side of the polygon that should not be seen can be seen, resulting in an unnatural image. Therefore, it has been necessary to control the position of the viewpoint so as not to go below the ground, or to produce other effects such as not copying the background in order to eliminate unnaturalness. On the other hand, it is desirable to move the viewpoint to any position in the virtual space and display the image so that the game can be produced, but it is not necessary to display the image that is expected to be seen in the real world. Couldn't produce enough worldview.

  The present invention solves such problems, and provides an image generation apparatus, an image generation method, and a program suitable for generating an image in which an object is viewed from all directions in a virtual space. Objective.

  In order to achieve the above object, the following invention is disclosed in accordance with the principle of the present invention.

An image generation apparatus according to a first aspect of the present invention includes a storage unit, a determination unit, and a generation unit.
The storage unit stores information on the position of the first object, the position of the second object, the position of the viewpoint, and the direction of the line of sight arranged in the virtual space.
The determination unit determines whether the viewpoint is arranged on the same side as the second object with respect to the first object, based on the position of the first object, the position of the second object, and the position of the viewpoint. It is judged whether it is arranged in.
Based on the position of the first object, the position of the second object, the position of the viewpoint, and the information on the direction of the line of sight, the generation unit viewed the virtual space from the position of the viewpoint to the direction of the line of sight An image representing the state is generated.
Further, when the determination unit determines that the viewpoint is arranged on the same side as the second object with respect to the first object, (a) the first object and the second object And generate an image that shows how you saw it,
(B) When it is determined that the second object is arranged on a different side, an image representing a state in which the second object is viewed is generated.
As a result, the image generation apparatus can generate an image in which the character object in the virtual space is viewed from all directions. Further, by generating an image from all directions, it is possible to produce a more realistic effect without a sense of incongruity.

The first object is a plane object, the second object is a solid object,
The storage unit further stores the shape of the plane object and the shape of the solid object,
The determination unit determines whether the viewpoint is arranged on the same side of the plane object with respect to the plane object based on the shape and position of the plane object, the shape and position of the stereoscopic object, and the position of the viewpoint. Determine whether they are placed on different sides,
Based on the shape and position of the plane object, the shape and position of the three-dimensional object, the position of the viewpoint, and information on the direction of the line of sight, the generation unit creates the virtual space from the position of the viewpoint to the direction of the line of sight. An image representing the appearance may be generated.

The storage unit further stores the position of the light source arranged on the same side as the solid object with respect to the plane object,
A calculation unit that calculates the shape and position of the shadow projected by the light source on the surface object by the light source in the virtual space from the shape and position of the surface object, the shape and position of the solid object, and the information on the light source Further comprising
Based on the shape and position of the shadow calculated by the calculation unit, the generation unit determines that the viewpoint is arranged on the same side as the solid object with respect to the plane object (a). In this case, an image representing the appearance of the plane object, the solid object, and the shadow is generated.
(B) When it is determined that the objects are arranged on different sides, an image representing the appearance of the solid object and the shadow may be generated.
As a result, the image generating apparatus can perform a more realistic effect without a sense of incongruity by generating an image including a shadow from all directions. Even if the plane object is not displayed, it is possible to effectively inform the user of the shape and position of the plane object using the shadow.

When the determination unit determines that the viewpoint is arranged on the same side as the solid object with respect to the plane object (a), the generation unit makes the plane object opaque,
(B) If it is determined that the plane object is arranged on a different side, the plane object is made transparent,
An image representing the appearance of the plane object, the solid object, and the shadow may be generated.
As a result, the image generation apparatus can generate an image in which the character object in the virtual space is viewed from all directions. Further, by generating an image from all directions, it is possible to produce a more realistic effect without a sense of incongruity.

The generation unit attenuates the brightness and / or saturation of the image of the area occupied by the shadow of the plane object, or makes the image of the area occupied by the shadow of the plane object achromatic. Thus, an image can be generated.
As a result, the image generation apparatus can generate an image in which the shape and position of the shadow are emphasized. For example, it is possible to generate a realistic image by darkening the shaded portion or making it achromatic such as black or gray.

When the determination unit determines that the viewpoint is arranged on the same side as the solid object (x) with respect to the plane object, the brightness of the image of the area occupied by the shadow in the plane object And / or saturation is attenuated,
(Y) If it is determined that they are arranged on different sides, the image of the area occupied by the shadow in the plane object is achromatic,
An image can be generated.
As a result, the image generating apparatus can change the effect of the shadow depending on the position of the viewpoint.

This image generation device is a game device for playing a game in a virtual space,
It further includes a setting unit that sets a range in which either or both of the viewpoint and the direction of the line of sight are movable, and the movable range may be set based on the game progress level of the user of the game device. Good.
As a result, the image generating apparatus can generate an image by moving the viewpoint or the line-of-sight direction as the game progresses. For example, it is possible to produce a game by moving the viewpoint and the line-of-sight direction according to the user's acquisition points, the number of stages cleared by the user, the user's play time, and the like.

The calculation unit calculates the shape and position of the area where the surface object and the three-dimensional object contact, instead of or in addition to the shape and position of the shadow,
The generation unit may generate an image including a region where the plane object and the solid object are in contact with each other instead of or in addition to the shadow.
As a result, the image generation apparatus can generate an image indicating a region where character objects are in contact with each other.

An image generation method according to another aspect of the present invention is an image generation method executed by an image generation apparatus having a storage unit, a determination unit, and a generation unit, and includes a determination step and a generation step.
The storage unit stores information on the position of the first object, the position of the second object, the position of the viewpoint, and the direction of the line of sight arranged in the virtual space.
In the determination step, the determination unit determines that the viewpoint is on the same side as the second object with respect to the first object, based on the position of the first object, the position of the second object, and the position of the viewpoint. Judge whether it is placed on a different side or not.
In the generation step, the generation unit moves the virtual object from the position of the viewpoint to the direction of the line of sight based on the position of the first object, the position of the second object, the position of the viewpoint, and the direction of the line of sight. An image representing the appearance of the space is generated.
Further, in the generation step, when it is determined by the determination step that the viewpoint is arranged on the same side as the second object with respect to the first object, the generation unit includes the first object, Generate an image representing the second object and how it was seen,
(B) When it is determined that the second object is arranged on a different side, the generation unit generates an image representing a state in which the second object is viewed.
As a result, the image generation apparatus using this image generation method can generate an image in which the character object in the virtual space is viewed from all directions. Further, by generating an image from all directions, it is possible to produce a more realistic effect without a sense of incongruity.

A program according to another aspect of the present invention causes a computer to function as a storage unit, a determination unit, and a generation unit.
The storage unit stores information on the position of the first object, the position of the second object, the position of the viewpoint, and the direction of the line of sight arranged in the virtual space.
The determination unit determines whether the viewpoint is arranged on the same side as the second object with respect to the first object, based on the position of the first object, the position of the second object, and the position of the viewpoint. It is judged whether it is arranged in.
Based on the position of the first object, the position of the second object, the position of the viewpoint, and the information on the direction of the line of sight, the generation unit viewed the virtual space from the position of the viewpoint to the direction of the line of sight An image representing the state is generated.
Further, when the determination unit determines that the viewpoint is arranged on the same side as the second object with respect to the first object, (a) the first object and the second object And generate an image that shows how you saw it,
(B) When it is determined that the second object is arranged on a different side, an image representing a state in which the second object is viewed is generated.
As a result, the program can cause the computer to function as an image generation device that generates an image of the character object in the virtual space viewed from all directions. Further, by generating an image from all directions, it is possible to produce a more realistic effect without a sense of incongruity.

The program of the present invention can be recorded on a computer-readable information storage medium such as a compact disk, flexible disk, hard disk, magneto-optical disk, digital video disk, magnetic tape, and semiconductor memory.
The above program can be distributed and sold via a computer communication network independently of the computer on which the program is executed. The information storage medium can be distributed and sold independently from the computer.

  According to the present invention, it is possible to provide an image generation apparatus, an image generation method, and a program suitable for generating an image in which an object is viewed from all directions in a virtual space.

(Example 1)
Examples of the present invention will be described below. In order to facilitate understanding of the present invention, an embodiment in which the present invention is realized using an information processing apparatus for games will be described. However, the embodiment described below is for explanation, and the present invention is described. It does not limit the range. Therefore, those skilled in the art can employ embodiments in which each or all of these elements are replaced with equivalent ones, and these embodiments are also included in the scope of the present invention.

  FIG. 1 is a schematic diagram showing a schematic configuration of a typical information processing apparatus 100 that performs the function of the image generation apparatus of the present invention by executing a program. Hereinafter, a description will be given with reference to FIG.

  The information processing apparatus 100 includes a CPU (Central Processing Unit) 101, a ROM (Read Only Memory) 102, a RAM (Random Access Memory) 103, an interface 104, a controller 105, an external memory 106, and an image processing unit 107. A DVD-ROM (Digital Versatile Disk-Read Only Memory) drive 108, a NIC (Network Interface Card) 109, and an audio processing unit 110.

  A DVD-ROM storing a game program and data is loaded into the DVD-ROM drive 108 and the information processing apparatus 100 is turned on to execute the program, thereby realizing the image generation apparatus of this embodiment. Is done.

  The CPU 101 controls the overall operation of the information processing apparatus 100 and is connected to each component to exchange control signals and data. Further, the CPU 101 uses arithmetic operations such as addition / subtraction / multiplication / division, logical sum, logical product, etc. using an ALU (Arithmetic Logic Unit) (not shown) for a storage area called a register (not shown) that can be accessed at high speed. , Logic operations such as logical negation, bit operations such as bit sum, bit product, bit inversion, bit shift, and bit rotation can be performed. In addition, the CPU 101 itself is configured so that saturation operations such as addition / subtraction / multiplication / division for multimedia processing, vector operations such as trigonometric functions, etc. can be performed at a high speed, and those provided with a coprocessor. There is.

  The ROM 102 records an IPL (Initial Program Loader) that is executed immediately after the power is turned on, and when this is executed, the program recorded on the DVD-ROM is read out to the RAM 103 and execution by the CPU 101 is started. The The ROM 102 stores an operating system program and various data necessary for operation control of the entire information processing apparatus 100.

  The RAM 103 is for temporarily storing data and programs, and holds programs and data read from the DVD-ROM and other data necessary for game progress and chat communication. Further, the CPU 101 provides a variable area in the RAM 103 and performs an operation by directly operating the ALU on the value stored in the variable, or temporarily stores the value stored in the RAM 103 in the register. Perform operations such as performing operations on registers and writing back the operation results to memory.

  The controller 105 connected via the interface 104 receives an operation input performed by a user when executing a game such as a mahjong game or a card game.

  The external memory 106 detachably connected via the interface 104 stores data indicating the play status (past results, etc.) of the mahjong game, data indicating the progress of the game, and chat communication log in the case of a network match. (Recorded) data and the like are stored in a rewritable manner. The user can record these data in the external memory 106 as appropriate by inputting an instruction via the controller 105.

  A DVD-ROM mounted on the DVD-ROM drive 108 stores a program for realizing the game and image data and audio data associated with the game. Under the control of the CPU 101, the DVD-ROM drive 108 performs a reading process on the DVD-ROM loaded therein, reads out necessary programs and data, and these are temporarily stored in the RAM 103 or the like.

  The image processing unit 107 processes the data read from the DVD-ROM by an image arithmetic processor (not shown) included in the CPU 101 or the image processing unit 107, and then processes the processed data on a frame memory ( (Not shown). The image information recorded in the frame memory is converted into a video signal at a predetermined synchronization timing and output to a monitor (not shown) connected to the image processing unit 107. Thereby, various image displays are possible.

  The image calculation processor can execute a two-dimensional image overlay calculation, a transparency calculation such as alpha blending, and various saturation calculations at high speed.

  Also, polygon information arranged in the virtual three-dimensional space and added with various texture information is rendered by the Z buffer method, and the polygon arranged in the virtual three-dimensional space from the predetermined viewpoint position is determined in the direction of the predetermined line of sight It is also possible to perform high-speed execution of operations for obtaining rendered images.

  Further, the CPU 101 and the image arithmetic processor operate in a coordinated manner, so that a character string can be drawn as a two-dimensional image in a frame memory or drawn on the surface of each polygon according to font information that defines the character shape. is there.

  In addition, information such as mahjong game tile images and card game card images is prepared on a DVD-ROM, and this is expanded in the frame memory, so that the current hand and hand are displayed on the screen. Will be able to.

  The NIC 109 is used to connect the information processing apparatus 100 to a computer communication network (not shown) such as the Internet, and is based on the 10BASE-T / 100BASE-T standard used when configuring a LAN (Local Area Network). To connect to the Internet using an analog modem, ISDN (Integrated Services Digital Network) modem, ADSL (Asymmetric Digital Subscriber Line) modem, cable television line A cable modem or the like and an interface (not shown) that mediates between these and the CPU 101 are configured.

  The audio processing unit 110 converts audio data read from the DVD-ROM into an analog audio signal and outputs the analog audio signal from a speaker (not shown) connected thereto. Further, under the control of the CPU 101, sound effects and music data to be generated during the progress of the game are generated, and sound corresponding to this is output from the speaker.

  When the audio data recorded on the DVD-ROM is MIDI data, the audio processing unit 110 refers to the sound source data included in the audio data and converts the MIDI data into PCM data. If the compressed audio data is in ADPCM (Adaptive Differential Pulse Code Modulation) format or Ogg Vorbis format, it is expanded and converted to PCM data. The PCM data can be output by performing D / A (Digital / Analog) conversion at a timing corresponding to the sampling frequency and outputting it to a speaker.

  In addition, the information processing apparatus 100 uses a large-capacity external storage device such as a hard disk so as to perform the same function as the ROM 102, the RAM 103, the external memory 106, the DVD-ROM mounted on the DVD-ROM drive 108, and the like. You may comprise.

Next, the virtual space handled in this embodiment will be described with reference to FIG.
As shown in the figure, a character object including a plane object 201 as a first object and a solid object 202 as a second object is arranged in the virtual space.
The plane object 201 is specifically a ground object in the virtual space. In this embodiment, it is assumed that the shape of the plane object 201 is a plane so that the present invention can be easily understood. However, the shape of the plane object 201 is not limited to a plane and may be a curved surface. A plurality of plane objects 201 may exist in the virtual space.
Specifically, the three-dimensional object 202 is a character object representing a person or an object existing in the virtual space. A plurality of the three-dimensional objects 202 may exist in the virtual space.
Further, a light source 203 and a viewpoint 204 are arranged in the virtual space. The light source 203 irradiates the plane object 201 and the three-dimensional object 202 with virtual light. In this embodiment, it is assumed that the shape of the light source 203 is a point. The color of light emitted from the light source 203 can be arbitrarily set. A light source 203 that is a point light source emits light having the same intensity in all directions in the virtual space. The image generation apparatus 300 generates an image in which various character objects such as the plane object 201 and the three-dimensional object 202 that are visible in the direction of the line of sight indicated by the line-of-sight vector 205 from the viewpoint 204 arranged in the virtual space are arranged. This image also includes a shadow 206 of the three-dimensional object 202 projected onto the surface of the plane object 201 by the light emitted from the light source 203.
Note that a configuration in which the light source 203 and the shadow 206 projected by the light emitted from the light source 203 are not included in the virtual space may be employed.

  Next, processing performed by the image generation apparatus 300 according to the present exemplary embodiment will be described with reference to the drawings.

  FIG. 3 is a diagram illustrating a configuration of the image generation apparatus 300 according to the present embodiment. The image generation apparatus 300 includes a storage unit 301, a calculation unit 302, a determination unit 303, and a generation unit 304.

  The storage unit 301 includes (1) the shape and position of the plane object 201 arranged in the virtual space, (2) the shape and position of the three-dimensional object 202, and (3) the same side as the three-dimensional object 202 with respect to the plane object 201. Information on the position of the light source 203 to be arranged, (4) the position of the viewpoint 204, and (5) the direction of the line of sight is stored.

  The shapes of the plane object 201 and the three-dimensional object 202 are represented by numerical data obtained by dividing the surface into polygons of minute polygons (typically triangles, quadrangles, etc.). The position of each character object is represented by the coordinates (x, y, z) of the representative point in each character object using an orthogonal coordinate system with three axes orthogonal to each other. The origin of the coordinate system may be set arbitrarily. The method of selecting the representative point is arbitrary, but for example, the center of gravity of each character object can be used. The coordinate system is not limited to this, and for example, a polar coordinate system such as a spherical coordinate system using one moving radius and two declination angles may be used. Further, a configuration may be adopted in which coordinate calculation or the like is performed by separately setting a global coordinate system (world coordinate system) representing the entire virtual space and a local coordinate system (body coordinate system) for each character object. .

  The positions of the light source 203 and the viewpoint 204 are represented by coordinates using an orthogonal coordinate system, like the positions of the character objects. As with each character object, the coordinate system used is not limited to this. The line-of-sight direction is represented by a line-of-sight vector 205 which is a direction vector with the viewpoint 204 as a base point. The length of the line-of-sight vector 205 is arbitrary, but is typically a unit vector.

Initial values of these pieces of information are stored in advance in a DVD-ROM mounted on the DVD-ROM drive 108, and are read into a predetermined storage area of the RAM 103 as needed under the control of the CPU 101. The shapes of the plane object 201 and the three-dimensional object 202 and the positions of the plane object 201, the three-dimensional object 202, the light source 203, and the viewpoint 204 are variable, and the user inputs instructions to change these positions using the controller 105. The CPU 101 can appropriately calculate in accordance with the progress / production of the game. The direction and size of the line-of-sight vector 205 are also variable. The CPU 101 stores the data shown in the above (1) to (5) stored in a predetermined storage area of the RAM 103 with the coordinates of the position instructed by the instruction input or information indicating the calculated shape and position. Update from time to time. For example, the CPU 101 calculates and updates these data at the timing of vertical synchronization. As a result, the latest data is stored in the storage unit 301.
Note that the CPU 101, the RAM 103, and the DVD-ROM drive 108 work together to function as the storage unit 301.

The calculation unit 302 uses the shape and position of the plane object 201, the shape and position of the three-dimensional object 202, and the position of the light source 203 to shade the solid object 202 onto the plane object 201 by light from the light source 203 in this virtual space. The shape and position of 206 are calculated. That is, the calculation unit 302 performs rendering. When the shape and position of the three-dimensional object 202 change, the shape and position of the shadow 206 change accordingly. Further, when the position of the light source 203 and the viewpoint 204 or the direction of the line-of-sight vector 205 changes, the shape and position of the shadow 206 change accordingly. The calculation unit 302 calculates the shape and position of the shadow 206 at a predetermined cycle (typically, a vertical synchronization cycle). The method of rendering is not limited by the present invention.
The CPU 101 functions as the calculation unit 302 by operating in cooperation with the image processing unit 107. In addition, when a configuration that does not include the light source 203 and the shadow 206 is employed in the virtual space, the image generation device 300 may not include the calculation unit 302.

The determination unit 303 determines whether the viewpoint 204 is arranged on the same side as the three-dimensional object 202 with respect to the plane object 201 based on the shape and position of the plane object 201, the shape and position of the three-dimensional object 202, and the position of the viewpoint 204. Determine whether it is placed on the side. For example, in the case of FIG. 2, the determination unit 303 determines that the viewpoint 204 is arranged on the same side as the solid object 202 with respect to the plane object 201 (ground) (that is, above the ground). As described above, since the position of the viewpoint 204 is variable, the viewpoint 204 may be arranged on a different side from the solid object 202 with respect to the plane object 201 (that is, below the ground). The determination unit 303 makes this determination at the same cycle as the predetermined cycle calculated by the calculation unit 302 and inputs the determination result to the generation unit 304.
Note that the CPU 101 operates in cooperation with the image processing unit 107 to function as the determination unit 303.

  The generation unit 304 includes the shape and position of the plane object 201, the shape and position of the solid object 202, the position of the viewpoint 204, the direction of the line of sight indicated by the line-of-sight vector 205, the shape and position of the shadow 206 calculated by the calculation unit 302, and Based on the determination result by the determination unit 303, an image representing a state in which the virtual space is viewed from the position of the viewpoint 204 in the direction of the line-of-sight vector 205 is generated.

  Specifically, when the determination unit 303 determines that (a) the viewpoint 204 is arranged on the same side as the solid object 202 with respect to the plane object 201, the generation unit 304 determines that the plane object 201, the solid object 202, Then, an image representing the appearance of the shadow 206 of the three-dimensional object 202 by the light from the light source 203 viewed from the viewpoint 204 in the direction of the line-of-sight vector 205 is generated.

On the other hand, when the determining unit 303 determines that the viewpoint 204 is arranged on the side different from the three-dimensional object 202 with respect to the plane object 201, the generating unit 304 uses the three-dimensional object 202 and the light from the light source 203. An image representing the appearance of the shadow 206 of the three-dimensional object 202 viewed from the viewpoint 204 in the direction of the line-of-sight vector 205 is generated.
Note that the CPU 101 functions as the generation unit 304 by operating in cooperation with the image processing unit 107.

  In the present embodiment, since the plane object 201 is the ground, when the viewpoint 204 is arranged on the same side as the solid object 202 with respect to the plane object 201 (above the ground), the generation unit 304 In this way, an image in which polygons arranged on different sides (under the ground) are blocked is generated. That is, in this case, the image generated by the generation unit 304 includes each character object (or part thereof) above the ground and cannot be seen under the ground. On the other hand, the state in which the viewpoint 204 is arranged on the side different from the solid object 202 with respect to the plane object 201 is a state in which the viewpoint 204 is under the ground, and each character object is viewed from this position in the real world. It is not possible. However, simply performing the same simulation as reality in a virtual space is often not sufficient as a game effect. Therefore, the viewpoint 204 can be submerged under the ground, and the production effect can be further enhanced by generating a virtual image viewed from all directions. In the present embodiment, the generation unit 304 displays the image of the plane object 201 when the viewpoint 204 is arranged on a different side from the three-dimensional object 202 with respect to the plane object 201 (that is, when the viewpoint 204 is below the ground). Is not displayed. Then, the generation unit 304 generates an image representing a state in which the three-dimensional object 202 and the shadow 206 of the three-dimensional object 202 due to the light from the light source 203 are viewed from the viewpoint 204 in the direction of the line-of-sight vector 205.

  FIG. 4 is an example showing the positional relationship between the plane object 201, the three-dimensional object 202, the light source 203, and the viewpoint 204 arranged in the virtual space. FIGS. 4A and 4C are views seen from the side of the plane object 201 (horizontal direction with respect to the plane), and FIGS. 4B and 4D show the line-of-sight vector 205 from the viewpoint 204. This is an example of an image viewed in the direction (that is, an image generated by the generation unit 304).

  In the case of FIG. 4A, the viewpoint 204 is arranged on the same side as the solid object 202 with respect to the plane object 201. As illustrated in FIG. 4B, the generation unit 304 looks at the plane object 201, the three-dimensional object 202, and the shadow 206 of the three-dimensional object 202 due to the light from the light source 203 in the direction of the line-of-sight vector 205. An image representing the appearance is generated.

  On the other hand, in the case of FIG. 4C, the viewpoint 204 is arranged on the side different from the solid object 202 with respect to the plane object 201. As illustrated in FIG. 4D, the generation unit 304 is an image representing a state in which the three-dimensional object 202 and the shadow 206 of the three-dimensional object 202 caused by the light from the light source 203 are viewed from the viewpoint 204 in the direction of the line-of-sight vector 205. Is generated. In this case, the image of the plane object 201 is not included. The shadow 206 is projected on a virtual surface 401 where the plane object 201 exists. However, the surface 401 shown in this figure is only described for explanation, and is not included in the image generated by the generation unit 304. In this embodiment, since the plane object 201 is a plane, the plane 401 is also a plane. However, if the plane object 201 is not a plane, the plane 401 is not a plane. The generation unit 304 can generate an image in which the three-dimensional object 202 is viewed from under the ground by hiding the image of the plane object 201.

  As described above, the image generating apparatus 300 can generate an image viewed from all directions in the virtual space without a sense of incongruity by performing control to display / not display the image of the plane object 201 according to the position of the viewpoint 204. . And it is possible to produce a more realistic feeling. Also, by applying the present invention to a game device, it is possible to produce an effective presentation that matches the world view of the game.

  Since the shadow 206 is projected on the virtual surface 401 where the plane object 201 exists, the user can easily know that the plane object 201 exists at a position where the shadow 206 exists. Furthermore, the user can easily know the shape and position of the plane object 201 from the shape and position of the shadow 206. For example, the shape and position of the ground can be easily grasped from the shape and position of the shadow 206 without outputting the ground image. As described above, the present invention can also be used as a method for notifying the surface object 201 of the shape and position without displaying the image of the surface object 201.

Instead of displaying / not displaying the image of the plane object 201, the image of the plane object 201 may be controlled to be opaque or transparent.
In this case, when the determination unit 303 determines that (a) the viewpoint 204 is arranged on the same side as the solid object 202 with respect to the plane object 201, the generation unit 304 determines the opaque plane object 201 and the solid object. 202 and an image representing the appearance of the shadow 206 of the three-dimensional object 202 by the light from the light source 203 viewed from the viewpoint 204 in the direction of the line-of-sight vector 205 is generated.
On the other hand, when the determination unit 303 determines that the viewpoint 204 is arranged on the side different from the three-dimensional object 202 with respect to the plane object 201, the generation unit 304 determines that the plane object 201 and the three-dimensional object 202 are made transparent. Then, an image representing the appearance of the shadow 206 of the three-dimensional object 202 by the light from the light source 203 viewed from the viewpoint 204 in the direction of the line-of-sight vector 205 is generated. As a result, the solid object 202 that is in contact with the plane object 201 does not appear to float in the air.

  Various patterns can be considered for the expression method of the shadow 206. Typically, the generation unit 304 relatively reduces (darkens) the brightness (or luminance) and / or saturation of the area overlapping the shadow 206 in the image of the plane object 201. Is generated. Alternatively, the area occupied by the shadow 206 may be an achromatic color of black or gray. The same applies when a shadow 206 is applied to a character object other than the plane object 201 (a shadow appears).

For example, when the determination unit 303 determines that (a) the viewpoint 204 is arranged on the same side as the three-dimensional object 202 with respect to the plane object 201, the generation unit 304 overlaps the shadow 206 in the image of the plane object 201. An image is generated by making the brightness and / or saturation of the region relatively small (darker). As a result, the shadow 206 is expressed. The degree to which the lightness or saturation is reduced is arbitrary, but the shadow 206 is enhanced if the lightness or saturation is greatly reduced. Alternatively, the area overlapping the shadow 206 may be black or gray achromatic.
On the other hand, when the determination unit 303 determines that the viewpoint 204 is arranged on the side different from the three-dimensional object 202 with respect to the plane object 201, the generation unit 304 is shaded in the plane 401 where the plane object 201 exists. An area overlapping with 206 is set to a black or gray achromatic color to generate an image. As a result, the shadow 206 is expressed. Alternatively, the image may be generated by relatively reducing either or both of the brightness and / or saturation of the area overlapping the shadow 206 in the image of the plane object 201.
In this way, by changing the display method of the shadow 206 according to the position of the viewpoint 204, it is possible to emphasize and produce an image viewed from a different viewpoint 204. In particular, the shape of the shadow 206 can be made clear by expressing the shadow 206 with an achromatic color.

  The generation unit 304 can generate an image on the assumption that a region in contact with the ground (plane object 201) on the surface of the three-dimensional object 202 is also included in the shadow 206.

(Image generation processing)
Next, image generation processing performed by the storage unit 301, the calculation unit 302, the determination unit 303, and the generation unit 304 of the image generation apparatus 300 will be described with reference to the flowchart of FIG. In the following description, the following situation is assumed as an example. That is, the plane object 201 is a planar stage object for dancing in the virtual space, and the three-dimensional object 202 is a dancer object for dancing. The light source 203 is a virtual light above the stage object, but is a point light source in this embodiment. The viewpoint 204 is a virtual camera that takes this dance scene, and can be moved to an arbitrary position in the virtual space. The virtual camera can also move below the stage object in the virtual space. The generation unit 304 generates an image photographed in the line-of-sight direction indicated by the line-of-sight vector 205 with this virtual camera. The generation unit 304 displays / hides the plane object 201 in accordance with the progress of the game, and generates an image such as a dancer object and its shadow object. In this embodiment, each unit of the image generation apparatus 300 periodically performs this image generation process at the timing of vertical synchronization. However, the timing for performing this process is not limited to this. This will be described in detail below.

  First, the calculation unit 302 indicates the shape and position of the plane object 201 (stage object) and the three-dimensional object 202 (dancer object), the position of the light source 203 (virtual light), the position of the viewpoint 204 (virtual camera), and the line-of-sight vector 205. The direction of the line of sight (the direction of the virtual camera) is acquired from the storage unit 301 (step S501). The acquired data is the latest data calculated and updated by the CPU 101 at a predetermined cycle such as vertical synchronization.

  Next, the calculation unit 302 calculates the shape and position of the shadow 206 (the shadow object of the dancer object) of the three-dimensional object 202 projected onto the plane object 201 based on the information acquired in step S501 (step S502).

  Based on the shape and position of the plane object 201 and the three-dimensional object 202 and the position of the viewpoint 204 in the information acquired in step S <b> 501, the determination unit 303 has the same viewpoint 204 as the three-dimensional object 202 with respect to the plane object 201. Whether it is on the side or a different side is determined (step S503). That is, the determination unit 303 determines whether the virtual camera is above or below the stage object on which the dancer object stands.

  When it is determined that the viewpoint 204 is on the same side as the three-dimensional object 202 (step S503; YES), that is, when the virtual camera is above the stage object, the generation unit 304 includes the information acquired in step S501, Based on the shape and position of the shadow 206 calculated in S502, an image in which the plane object 201, the three-dimensional object 202, and the shadow 206 are viewed from the viewpoint 204 in the direction of the line-of-sight vector 205 is generated (step S504). That is, the generation unit 304 generates an image obtained by photographing a stage object, a dancer object standing on the stage object, and a shadow object of the dancer object with a virtual camera.

  On the other hand, when it is determined that the viewpoint 204 is on a different side from the three-dimensional object 202 (step S503; NO), that is, when the virtual camera is below the stage object, the generation unit 304 includes the information acquired in step S501. Based on the shape and position of the shadow 206 calculated in step S502, an image in which the three-dimensional object 202 and the shadow 206 are viewed from the viewpoint 204 in the direction of the line-of-sight vector 205 is generated (step S505). That is, the generation unit 304 generates an image obtained by photographing a dancer object standing on a stage object and a shadow object of the dancer object with a virtual camera. This image does not include a stage object.

  The image generated by the generation unit 304 in step S504 or S505 in this way is output to a monitor connected to the image processing unit 107.

  Note that when the viewpoint 204 exists on the plane where the plane object 201 exists, the generation unit 304 performs the process of step S504 to generate an image including the plane object 201 displayed in a straight line. An image that does not include the plane object 201 may be generated by performing the process of step S505.

  In step S503, if the generation unit 304 determines that the viewpoint 204 is on the same side as the three-dimensional object 202 (step S503; YES), the plane object 201 is made opaque, while the viewpoint 204 is the three-dimensional object. If it is determined that the object is on a different side from 202 (step S503; NO), the plane object 201 may be transparent. The generation unit 304 may generate an image in which the plane object 201, the three-dimensional object 202, and the shadow 206 that are opaque or transparent are viewed from the viewpoint 204 in the direction of the line-of-sight vector 205.

The present embodiment can be variously modified and applied.
In the above-described embodiment, the light source 203 is a point light source, but is not limited to this. For example, the light source 203 may be a character object (surface light source) having a three-dimensional or planar spread. In this case, the calculation unit 302 obtains the shape and position of the shadow 206 formed by light emitted from a certain point on the light source object, and similarly, all the points on the light source object (or an amount that can be approximately regarded as all). The shape and position of the shadow 206 are obtained at the point of () and integrated. Each point in the shadow 206 area is associated with an integral amount (light quantity) indicating the darkness of the shadow. The generation unit 304 can generate an image by adding shades to the color of the shadow 206 according to the amount of light, or by changing both or either one of brightness and saturation.

  The calculation unit 302 may calculate the shape and position of the shadow 206 by approximating that the light source 203 exists at infinity from the three-dimensional object 202 and the light rays emitted from the light source 203 to the three-dimensional object 202 are parallel. . For example, it is desirable to perform this approximation when the sun is used as the light source 203.

  A plurality of light sources 203 may exist in the virtual space. In this case, for example, the calculation unit 302 obtains the shape and position of each shadow 206 formed by the light emitted from each light source 203. The calculation unit 302 sets the calculated logical sum of the shapes of the shadows 206 as the final shape of the shadows 206. Then, the generation unit 304 generates an image using the final shadow 206 calculated by the calculation unit 302. Alternatively, the calculation unit 302 obtains the respective shadows 206, and the generation unit 304 adds the shades of the shades 206 in a stepwise manner according to the degree of overlap of the respective shadows 206, or changes either or both of the brightness and the saturation. Then, an image may be generated. The method for obtaining the shape and position of the shadow 206 is not limited to this.

  The shape of the light source 203 is not limited to the point light source and the surface light source described above. For example, a spotlight whose light amount converges in a conical shape may be used. In this case, the light is brightest near the center of the cone and attenuates and darkens toward the end. Further, for example, cylindrical light whose light amount converges into a cylindrical shape may be used. In this case, the light is brightest near the center of the cylinder and becomes darker toward the end. Based on the amount of light, the generation unit 304 can add a shade to the color of the shadow 206, or can change both or either one of brightness and saturation.

  In the embodiment described above, the plane object 201 is a plane, but the present invention is not limited to this. For example, it may be a curved surface with unevenness or an inclination on the surface, or a set of polygons.

  In the embodiment described above, the plane object 201 is the ground, but the present invention is not limited to this. For example, it may be a water surface, a sea surface, or a contact surface between substances having different refractive indexes. For example, by applying the present invention to a method for expressing the sea surface when viewed from the sea toward the sky, the sea surface can be expressed by a shadow of a ship or the like projected onto the sea surface. Further, for example, by applying the present invention to a method for generating an image seen through a transparent glass, the glass surface can be expressed by the shadow of an object projected on the glass surface.

  In the embodiment described above, the shadow 206 of the three-dimensional object 202 is generated, but the present invention is not limited to this. For example, the three-dimensional object 202 may be a character object having an arbitrary shape such as a two-dimensional character object represented by a plane in addition to a three-dimensional character object surrounded by several planes / curved surfaces such as a person object.

  As one application example, the generation unit 304 uses the color of the three-dimensional object 202 in the vicinity of the boundary between the shadow 206 of the three-dimensional object 202 projected on the plane object 201 or the plane 401 where the plane object 201 exists and a non-shadow portion. An image in which the boundary line (shadow outline) is blurred may be generated by using an intermediate color between the color of the shadow and the shadow 206. As a result, a smooth image can be obtained.

  As one application example, the generation unit 304 may generate an image obtained by enlarging or reducing an image of the virtual space viewed from the viewpoint 204 in the direction of the line of sight indicated by the line-of-sight vector 205. In this case, for example, when the line-of-sight vector 205 is a unit vector, the length of the line-of-sight vector 205 is set as an image enlargement ratio. Or you may provide the parameter which shows the expansion ratio of an image separately. The enlargement ratio may be set by the user using the controller 105, or the CPU 101 may set it according to the progress of the game. Then, the generation unit 304 generates an enlarged or reduced image based on the set enlargement ratio. As a result, it is possible to produce a more realistic effect.

  As one application example, the range in which the viewpoint 204 can be moved and the range in which the direction of the line of sight can be moved may be changed according to the progress of the game. For example, the greater the number of user acquisition points (game score, etc.), the wider the range in which the viewpoint 204 can be moved. For example, as the user clears more game stages, the range in which the viewpoint 204 can be moved is set wider. For example, the longer the user play time, the wider the range in which the viewpoint 204 can be moved. The CPU 101 counts parameters based on the progress of the game, such as user acquisition points, the number of stages cleared by the user, and the user's play time, and stores them in the RAM 103. Based on these parameters, the viewpoint 204 can be moved. A range and / or a movable range in the line-of-sight direction may be set. The movable range is a solid (or a set of solids) such as a sphere, hemisphere, or cube in a virtual space, a plane (or a set of planes) such as a circle or a polygon, a line segment (or a set of line segments), or a point. (Or a set of points) or any other graphic. The shape of these figures may be stored in advance in the storage unit 301 in association with the game progress level such as the number of points, the number of stages, the play time, etc. of the user, or the CPU 101 may change each time depending on the progress of the game. It may be obtained by calculation. As a result, the image generating apparatus 300 can generate a variety of images in accordance with the progress of the game and give a sophisticated effect.

  As one application example, the moving speed of the viewpoint 204 may be changed according to the progress of the game. The CPU 101 calculates and stores in the RAM 103 parameters based on the progress of the game, such as the user's acquisition points, the number of stages cleared by the user, and the user's play time, and the moving speed of the viewpoint 204 is determined based on these parameters. You only have to set it. The moving speed may be stored in advance in the storage unit 301 in association with the game progress level such as the number of points, the number of stages, and the play time, or calculated by the CPU 101 each time depending on the progress of the game. Also good. As a result, the image generating apparatus 300 can generate a variety of images in accordance with the progress of the game and give a sophisticated effect.

As one application example, the calculation unit 302 may obtain the shape and position of an area where the plane object 201 and the three-dimensional object 202 are in contact with each other instead of the shade 206 formed by the light from the light source 203. In this case, the light source 203 may or may not exist. Further, the determination unit 303 and the generation unit 304 may perform the same processing as described above, regarding the area where the plane object 201 and the three-dimensional object 202 are in contact with each other as the shadow 206.
For example, FIG. 6 is a diagram for explaining a region 601 where the plane object 201 and the three-dimensional object 202 are in contact (indicated as 601a and 601b in the drawing). FIG. 6A is an example of an image generated by the generation unit 304 when the viewpoint 204 is arranged on the same side as the three-dimensional object 202 with respect to the plane object 201. FIG. 6B is an example of an image generated by the generation unit 304 when the viewpoint 204 is arranged on a different side with respect to the plane object 201. In this example, the dancer object (solid object 202) stands on the stage object (plane object 201). A region 601 where the plane object 201 and the three-dimensional object 202 are in contact corresponds to the sole of the dancer object. The calculation unit 302 regards these regions 601a and 601b as the shadow 206 (or substitutes for the shadow 206) and calculates the shape and position of the shadow 206. Then, the generation unit 304 generates an image including the calculated shadow 206 (contacted region 601) in the same manner as the above-described processing. The shadow 206 may include a contact area 601.
Thus, the present invention can be used as a method for generating an image showing an area where a plurality of character objects are in contact. For example, it is possible to generate an image that more precisely represents the shape of the sole of the dancer object.

(Example 2)
Next, another embodiment of the present invention will be described. In the above-described embodiment, the first object is a plane and the second object is a solid. However, in the present embodiment, the first and second objects may be either a plane or a solid. That is, both the first and second objects may be three-dimensional, both may be planes, or the first object may be three-dimensional and the second object may be plane. The determination unit 303 arranges the viewpoint 204 on the same side as the second object or on a different side with respect to the first object based on the distance between the viewpoint 204 and the first and second objects. Judge what will be done. Since the other configuration is the same as that of the above-described embodiment, the description of the overlapping part is omitted. This will be described in detail below.

  The determination unit 303 obtains a distance D1 between the viewpoint 204 and the first object and a distance D2 between the viewpoint 204 and the second object. In other words, the determination unit 303 determines the length of the first vector V1 that connects the viewpoint 204 and the representative point (such as the center of gravity) of the first object (that is, the distance D1), the representative point of the viewpoint 204 and the second object, And the length of the second vector V2 (that is, the distance D2). When D1 <D2, the determination unit 303 determines that the viewpoint 204 is arranged on the same side as the second object with respect to the first object. On the other hand, when D1> D2, the determination unit 303 determines that the viewpoint 204 is arranged on a different side from the second object with respect to the first object. Note that, when D1 = D2, the determination unit 303 may determine either, but in this embodiment, it is determined that they are arranged on the same side. Since the processing performed by the storage unit 301, the calculation unit 302, and the generation unit 304 is the same as that in the above-described embodiment, the description thereof is omitted.

  In the present embodiment, the determination unit 303 can also determine by another method different from the above determination method. For example, when the angle θ formed by the first vector V1 and the third vector (V2−V1) obtained by subtracting the first vector from the second vector is 90 ° or less, the determination unit 303 determines that the viewpoint 204 is the first object. May be determined to be arranged on the same side as the second object. On the other hand, when the angle θ is less than 90 °, the determination unit 303 may determine that the viewpoint 204 is arranged on a different side from the second object with respect to the first object.

This embodiment is particularly effective when there are multiple objects in the same virtual space and it is desired to control a specific object from any position in the virtual space regardless of the positional relationship between these objects. It is. That is, a priority order to be displayed is set for an object in the virtual space, and an object with a higher priority order can be displayed with priority over an object with a lower priority order. Depending on the positional relationship between the viewpoint 204 and the first and second objects, an object with a higher priority may be hidden from an object with a lower priority from the viewpoint 204. Therefore, (a) when the viewpoint 204 is arranged on the same side as the second object with respect to the first object, that is, in a positional relationship in which an object with high priority is not hidden, the generation unit 304 An image representing the appearance of viewing the first object and the second object is generated. On the other hand, (b) when the viewpoint 204 is arranged on a different side from the second object with respect to the first object, that is, in a positional relationship where an object with a high priority is hidden behind an object with a low priority, The generation unit 304 generates an image representing a state where the second object is viewed. In this case, the image generated by the generation unit 304 does not include an object having a low priority.
Thus, according to the present embodiment, the image generation apparatus 300 can generate an image in which an object is viewed from all directions regardless of the shape of the object.

  Also in the present embodiment, when the determination unit determines that the viewpoint 204 is placed on the same side as the second object (a) with respect to the first object, the generation unit selects the first object. If it is determined to be opaque and (b) it is determined to be arranged on a different side, the first object is set to be transparent, and an image representing a state in which the first object and the second object are viewed is generated. May be. In addition, the calculation unit 302 obtains the shape and position of the shadow 206 projected by the second object onto the surface of the first object by the light from the light source 203, and the generation unit 304 generates an image including the shadow 206. You may comprise as follows.

  The present invention is not limited to the above-described embodiments, and various modifications and applications are possible. Moreover, it is also possible to freely combine the components of the above-described embodiments.

  A program for operating the image generating apparatus 300 as all or part of the apparatus is stored and distributed in a computer-readable recording medium such as a memory card, CD-ROM, DVD, or MO (Magneto Optical disk). May be installed in another computer and operated as the above-described means, or the above-described steps may be executed.

  Furthermore, the program may be stored in a disk device or the like included in a server device on the Internet, and may be downloaded onto a computer by being superimposed on a carrier wave, for example.

  As described above, according to the present invention, it is possible to provide an image generation device, an image generation method, and a program suitable for generating an image in which an object is viewed from all directions in a virtual space.

It is a figure which shows schematic structure of the typical information processing apparatus with which the image generation apparatus of this invention is implement | achieved. It is a conceptual diagram for demonstrating a surface object, a solid object, a light source, a viewpoint, a gaze vector, and a shadow. It is a figure for demonstrating the structure of an image generation apparatus. (A) It is a figure of the example by which the viewpoint was arrange | positioned with respect to a plane object on the same side as a solid object. (B) It is an example of the image which the production | generation part produced | generated. (C) It is a figure of the example arrange | positioned on the side different from a solid object with respect to a plane object. (D) It is an example of the image which the production | generation part produced | generated. It is a flowchart for demonstrating an image generation process. (A) And (b) is a figure of the example which shows the area | region where the plane object and the solid object contacted.

Explanation of symbols

100 Information processing apparatus 101 CPU
102 ROM
103 RAM
104 Interface 105 Controller 106 External Memory 107 Image Processing Unit 108 DVD-ROM Drive 109 NIC
DESCRIPTION OF SYMBOLS 110 Sound processing part 201 Plane object 202 Solid object 203 Light source 204 Viewpoint 205 Line-of-sight vector 206 Shading 300 Image generation device 301 Storage part 302 Calculation part 303 Judgment part 304 Generation part 401 Surface 601 where plane object exists Surface object and solid object Touched area

Claims (10)

A storage unit for storing information on the position of the first object, the position of the second object, the position of the viewpoint, and the direction of the line of sight arranged in the virtual space;
From the information on the position of the first object, the position of the second object, and the position of the viewpoint, the viewpoint is arranged on the same side as the second object or on a different side with respect to the first object. A judgment unit that judges whether or not
An image representing a state in which the virtual space is viewed from the position of the viewpoint to the direction of the line of sight based on the position of the first object, the position of the second object, the position of the viewpoint, and the information on the direction of the line of sight When the determination unit determines that the viewpoint is arranged on the same side as the second object with respect to the first object, (a) the first object, Generate an image representing the second object and how it was seen,
(B) An image generation apparatus comprising: a generation unit that generates an image representing a state of viewing the second object when it is determined that the second object is arranged on a different side. The image generation apparatus according to claim 1,
The first object is a plane object,
The second object is a three-dimensional object,
The storage unit further stores the shape of the plane object and the shape of the solid object,
The determination unit arranges the viewpoint on the same side as the solid object with respect to the plane object from information on the shape and position of the plane object, the shape and position of the solid object, and the position of the viewpoint. Or be placed on a different side,
Based on the shape and position of the plane object, the shape and position of the three-dimensional object, the position of the viewpoint, and information on the direction of the line of sight, the generation unit generates the virtual space from the position of the viewpoint to the direction of the line of sight. An image generation device that generates an image representing a state of viewing the screen. The image generation apparatus according to claim 2,
The storage unit further stores a position of a light source arranged on the same side as the solid object with respect to the plane object,
A calculation unit that calculates the shape and position of a shadow projected by the light source on the surface object by the light source in the virtual space from the shape and position of the surface object, the shape and position of the solid object, and the information on the light source. In addition,
When the viewpoint is arranged on the same side as the three-dimensional object with respect to the plane object by the determination unit based on the shape and position of the shadow calculated by the calculation unit, If determined, an image representing the appearance of the plane object, the solid object, and the shadow is generated,
(B) An image generation device that generates an image representing a state in which the solid object and the shadow are viewed when it is determined that they are arranged on different sides. The image generation device according to claim 2 or 3,
When the determination unit determines that the viewpoint is arranged on the same side as the solid object with respect to the plane object (a), the generation unit makes the plane object opaque,
(B) If it is determined that the plane object is arranged on a different side, the plane object is made transparent,
An image generation apparatus that generates an image representing a state in which the plane object, the solid object, and the shadow are viewed. The image generation device according to claim 3,
The generation unit attenuates the brightness and / or saturation of the image of the area occupied by the shadow of the plane object, or achromatic color of the image of the area occupied by the shadow of the plane object. An image generating apparatus characterized by generating an image. The image generation apparatus according to claim 5,
When the determination unit determines that the viewpoint is arranged on the same side as the solid object with respect to the plane object, (x) an image of an area occupied by the shadow in the plane object Attenuate the brightness and / or saturation of
(Y) If it is determined that they are arranged on different sides, the image of the area occupied by the shadow in the plane object is achromatic,
An image generation apparatus characterized by generating an image. The image generation apparatus according to claim 1,
The image generation device is a game device for playing a game in a virtual space,
It further comprises a setting unit for setting a range in which both or one of the viewpoint and the direction of the line of sight can move,
The movable range is set based on a user's game progress level by the game device. The image generation device according to claim 3,
The calculation unit calculates the shape and position of the area where the plane object and the solid object contact, instead of or in addition to the shape and position of the shadow,
The image generation apparatus, wherein the generation unit generates an image including a region where the plane object and the solid object contact in place of or in addition to the shadow. An image generation method executed by an image generation apparatus having a storage unit, a determination unit, and a generation unit,
The storage unit stores information on the position of the first object, the position of the second object, the position of the viewpoint, and the direction of the line of sight arranged in the virtual space,
The determination unit determines whether the viewpoint is arranged on the same side as the second object with respect to the first object, based on the position information of the first object, the position of the second object, and the position of the viewpoint. A determination step for determining whether to be placed on the side,
Based on the position of the first object, the position of the second object, the position of the viewpoint, and the information on the direction of the line of sight, the generation unit views the virtual space from the position of the viewpoint to the direction of the line of sight. A generation step of generating an image representing the appearance of the image, wherein the determination step determines that the viewpoint is arranged on the same side as the second object with respect to the first object, (a) The generation unit generates an image representing the appearance of the first object and the second object,
(B) a generation step in which, when it is determined that the second unit is arranged on a different side, the generation unit generates an image representing a state in which the second object is viewed;
An image generation method comprising: Computer
A storage unit for storing information on the position of the first object, the position of the second object, the position of the viewpoint, and the direction of the line of sight arranged in the virtual space;
From the information on the position of the first object, the position of the second object, and the position of the viewpoint, the viewpoint is arranged on the same side as the second object or on a different side with respect to the first object. A judgment unit that judges whether or not
An image representing a state in which the virtual space is viewed from the position of the viewpoint to the direction of the line of sight based on the position of the first object, the position of the second object, the position of the viewpoint, and the information on the direction of the line of sight When the determination unit determines that the viewpoint is arranged on the same side as the second object with respect to the first object, (a) the first object, Generate an image representing the second object and how it was seen,
(B) A program that functions as a generation unit that generates an image representing a state of viewing the second object when it is determined that the second object is arranged on a different side.

Images