JP2001283246A - Three-dimensional image compositing device, its method, information storage medium program distributing device and its method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To add gradation according to distance from a viewpoint to a display screen without remarkably increasing processing burden. SOLUTION: To which of the closest view 64, a close view 62, focus depth 60, a distant view 58 or the most distant view 56 each pixel belongs is decided based on Z value held in a Z buffer. Alpha values (depth range information) corresponding to depth ranges are set in respective pixels. Translucent composition of color information of each pixel is performed with color information of other pixels in forms corresponding to the alpha values. For example, the translucent composition is performed for an original image by shifting prescribed pixels to the left and right for the pixels belonging to the distant view 58 and the most distant view 56. In addition, the translucent composition is further performed to the original image by shifting up and down by prescribed pixels for the pixels belonging to the closet view 56.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus and method for synthesizing a three-dimensional image, an information storage medium, an apparatus and a method for distributing a program, and more particularly to a technique for performing a blurring process on a three-dimensional image.

[0002]

2. Description of the Related Art In three-dimensional image processing, an object arranged in an object space (virtual three-dimensional space) is projected onto a perspective projection plane arranged in front of a viewpoint, and this projected image is displayed and output on a monitor. In the perspective projection processing, the vertex coordinates (UVW) of each polygon constituting the object represented by the viewpoint coordinate system are divided by the U value (depth coordinates).
In this way, objects arranged farther from the viewpoint are made to look smaller, thereby expressing perspective on the display screen.

[0003]

In the above image processing,
Objects placed far from the viewpoint and objects placed near the viewpoint are displayed in an image in a state where the focus is finely focused. However, only an object located within the depth of field (depth of focus), such as a photograph taken with an aperture value set to open, is focused on, and the distance from the focus for other objects is small. If an image can be displayed in such a manner that the focal point becomes out of focus as the distance increases, the range of image expression can be widened and the reality of the displayed image can be increased.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its object to provide a three-dimensional image capable of adding a blur according to a distance from a viewpoint to a display image without greatly increasing a processing load. An object of the present invention is to provide a synthesizing device, a three-dimensional image synthesizing method, an information storage medium, a program distribution device, and a program distribution method.

[0005]

In order to solve the above-mentioned problems, a three-dimensional image synthesizing apparatus according to the present invention comprises a display image storage means for storing color information and depth information of each pixel constituting a display image; Blur processing means for translucently combining the color information of each pixel with the color information of other pixels in a manner corresponding to the depth information.

Further, in the three-dimensional image synthesizing method according to the present invention, a step of storing color information and depth information of each pixel constituting a display image, and a step of storing the color information of each pixel in a form corresponding to the depth information. Translucently synthesizing the color information of another pixel.

Further, the information storage medium according to the present invention stores the color information and the depth information of each pixel constituting the display image, and stores the color information of each pixel in another form according to the depth information. Translucently synthesizing the color information of the pixel; and storing a program for causing a computer to execute the step.

According to another aspect of the present invention, there is provided a program distribution apparatus for storing color information and depth information of each pixel constituting a display image, and for storing the color information of each pixel in another form according to the depth information. Translucently synthesizing the color information of the pixels.

According to another aspect of the present invention, there is provided a program distribution method, comprising the steps of: storing color information and depth information of each pixel constituting a display image; and storing the color information of each pixel in another form in accordance with the depth information. Translucently synthesizing the color information of the pixels.

In the present invention, color information and depth information are stored for each pixel, and the color information of the pixel is translucent with respect to the color information of other pixels in a manner corresponding to the depth information. Combine. The depth information is information relating to the distance from the viewpoint, and for example, a known Z value or the like can be used. The translucent composition is, for example, a process of proportionately adding color information of a pixel to be combined and color information of a pixel to be combined. In this way, it is possible to realize the blurring processing according to the distance from the viewpoint without greatly increasing the processing load.

In one aspect of the present invention, the blur processing means includes depth range information setting means for setting depth range information for each pixel based on the depth information, and the depth set by the depth range setting means. The color information of each pixel is translucently combined with the color information of the other pixels in a mode corresponding to the range information. In this case, the blurring process can be performed by changing the mode in units of the depth range.

Further, in one aspect of the present invention, the blur processing means is configured such that, based on the depth information, each pixel is a back pixel representing an object located on a back side of a predetermined focal depth in a virtual three-dimensional space. First pixel determining means for determining whether or not each pixel is present, and determining whether or not each pixel is a focus pixel representing an object located within a predetermined focal depth in a virtual three-dimensional space based on the depth information. The image processing apparatus includes a second pixel determining unit and a translucent composition limiting unit that restricts translucent composition of at least the color information of the focus pixel with respect to the color information of the back pixel. This makes it possible to suppress the color information of the back pixel from being semi-transparently combined with the color information of the focus pixel, thereby suppressing an unnatural blurring process.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a diagram showing a configuration of a game device according to one embodiment of the present invention. Game device 10 shown in FIG.
Is an embodiment of a three-dimensional image synthesizing apparatus according to the present invention, and is configured by mounting a DVD 25 as an information storage medium to a consumer game machine 11 connected to a monitor 18 and a speaker 22. . Here, the DVD 25 is used to supply the game program and the game data to the consumer game machine 11, but any other information storage medium such as a CD-ROM or a ROM card can be used. In addition, as described later, a game program and game data can be supplied to the consumer game device 11 from a remote place via a communication network. Hereinafter, the three-dimensional image synthesizing apparatus, the three-dimensional image synthesizing method, and the information storage medium according to the present invention will be described through the description of the game apparatus 10.

In the home-use game machine 11, a microprocessor 14, an image processing unit 16, a main memory 26, and an input / output processing unit 30 are connected by a bus 12 so as to be able to communicate with each other.
Further, the input / output processing unit 30 is connected to the controller 32, the audio processing unit 20, and the DVD reproducing unit 24. Each component of the consumer game machine 11 other than the controller 32 is housed in a housing. For the monitor 18, for example, a home television receiver is used, and for the speaker 22, for example, its built-in speaker is used.

The microprocessor 14 has an R (not shown)
Operating system and DVD2 stored in OM
Based on the game program read from the control unit 5, each unit of the consumer game machine 11 is controlled. The bus 12 is used for exchanging addresses and data between the units of the consumer game machine 11. The main memory 26 has a DVD 25
The game program and the game data read from are written as necessary. The image processing unit 16 is a VRAM
Receives the image data sent from the microprocessor 14, draws the game screen on the VRAM, converts the content into a predetermined video signal, and outputs it to the monitor 18 at a predetermined timing. That is, the image processing unit 16 sends the vertex coordinates (X, Y, Z), vertex color information (R, G, B), and texture coordinates (VX, V) of each polygon in the viewpoint coordinate system from the microprocessor 14.
Y) and an alpha value. Then, the color information, the Z value (depth information), the alpha value, and the like of each pixel constituting the display image are drawn in the VRAM using the information. This display image is output to the monitor 18 at a predetermined timing. When drawing a pixel in the VRAM, a pixel test can be arbitrarily executed. The pixel test includes an alpha test, a destination alpha test, and a depth test. Microprocessor 1
An arbitrary pixel test is performed in accordance with the instruction from 4. Among them, the alpha test compares the alpha value of a pixel to be rendered with a given reference alpha value, and if a predetermined condition is not satisfied, rendering of that pixel is restricted.
The destination alpha test is the alpha value (destination alpha value) of the pixel at the drawing destination (the pixel already drawn at the drawing destination address of the VRAM)
Is compared with a predetermined value (0x80). If the predetermined condition is not satisfied, drawing of the pixel is restricted. The depth test is based on the Z value of the drawing pixel and (prepared in VRAM)
The Z value of the Z buffer is compared, and if the predetermined condition is not satisfied, drawing of the pixel is restricted. VRA
When a pixel is drawn on M, masking can be performed, and writing of color information, Z value, and alpha value of each pixel can be arbitrarily prohibited.

The input / output processing unit 30 is an interface for relaying data communication between the controller 32, the audio processing unit 20, the DVD reproducing unit 24, and the microprocessor 14. The controller 32 is input means for the player to perform a game operation. The input / output processing unit 30 scans the operation states of various buttons of the controller 32 at regular intervals (for example, every 1/60 second), and passes an operation signal representing the scan result to the microprocessor 14 via the bus 12. The microprocessor 14 determines a game operation of the player based on the operation signal. The audio processing unit 20 includes a sound buffer,
Data such as music and game sound effects read from the DVD 25 and stored in the sound buffer is reproduced and output from the speaker 22. The DVD reproducing unit 24 reads a game program and game data recorded on the DVD 25 according to an instruction from the microprocessor 14.

Hereinafter, the game apparatus 10 having such a configuration will be described.
, A technique for performing a blurring process on a game image according to the distance from the viewpoint will be described.

FIG. 2 is a diagram showing an example of a game image displayed on the monitor 18 of the game apparatus 10. As shown in FIG. The game image shown in the figure represents a part of a virtual three-dimensional space (game space) constructed on the main memory 26, and a grass object 44 is shown near the viewpoint, and a car object is located on the other side. 40 is represented. Further, on the other side, a house object 46 and a mountain object 42 are shown. Among them, according to the game device 10 according to the embodiment of the present invention, the grassy object 44, the house object 46, and the mountain object 42 are subjected to the blurring processing. On the other hand, the blurring process is not performed on the car object 40. The mountain object 42 located farther from the viewpoint than the house object 46 has a large blur. Thus, with the depth of focus before and after the car object 40, the object 40 is displayed so as to stand out from other objects. Note that the depth of focus corresponds to the depth of field of the camera, and refers to a range in the line-of-sight direction that is considered to be in focus in practical use.

FIG. 3 is a flowchart illustrating a game process executed by the game device 10. As shown in FIG.
First, game environment processing is performed based on the game program and game data read from the VD 25 (S10).
1). In the game environment processing, the positions and orientations of all static and dynamic objects in the virtual three-dimensional space are calculated. The static objects, such as the grass object 44, the mountain object 42, and the house object 46, do not change their positions even when the game progresses. On the other hand, the dynamic object changes its position and orientation as the game progresses, like the car object 40. The position and orientation of the dynamic object change according to a game program or an operation signal input from the controller 32. In the game environment processing, a viewpoint and a visual field range are also calculated. Then, the objects that are separated from the visual field range are excluded from the targets of the subsequent game processing.

Next, the microprocessor 14 performs a geometry process (S102). In the geometry processing, coordinate conversion from the world coordinate system to the viewpoint coordinate system is performed. Further, the color information of the vertices of each polygon constituting the object is corrected based on the light source information (color and position of the light source). Further, a clipping process is performed.

Thereafter, the microprocessor 14 sends the vertex coordinates, vertex color information, texture coordinates and alpha value of each polygon belonging to the visual field range to the image processing unit 16, and the image processing unit 16 stores the coordinates in the VRAM based on the information. A display image is formed in an input buffer provided in
3). Further, the image processing section 16 performs a perspective blurring process in accordance with an instruction from the microprocessor 14 (S10).
4). After finishing the perspective blur processing, the VRA of the image processing unit 16
The game image formed in the M output buffer is read out at a predetermined timing and displayed on the monitor 18.

FIGS. 4 and 5 are flowcharts for explaining the perspective blurring processing executed by the game apparatus 10 in detail.
In the perspective blurring processing, first, for the display image formed on the VRAM in S103, the alpha value (depth range information) of each pixel is set according to the distance (Z value) from the viewpoint (S201 to S205). FIG. 6 is a diagram for explaining an alpha value setting rule. As shown in the drawing, among the objects belonging to the visual field range 54, the alpha value is set to 0xa0 for the pixel representing the object arranged in the closest view 64 (the depth range closest to the viewpoint 50) whose Z value is larger than Z3. I do. Also, when the Z value changes from Z2 to Z
The alpha value is set to 0x90 for pixels representing objects placed in the near view 62 (the depth range next to the viewpoint 50) that is between three. Also, when the Z value is Z1
The alpha value is set to 0x80 for pixels representing objects located within a depth of focus 60 (depth range that is considered practically in focus when viewed from the viewpoint 50), which is between 0 and Z2. Also, when the Z value changes from Z0 to Z
1 (a depth of focus 60 from the viewpoint 50).
The alpha value is set to 0x70 for a pixel representing an object located in a depth range just beyond (the depth range just behind). Further, for a pixel representing an object arranged in the farthest view 56 (the farthest depth range viewed from the viewpoint 50) whose Z value is less than Z0, the alpha value is set to 0x6.
Set to 0. As Z0 to Z3, Z3>Z2> Z1
> Z0 is set in advance.

For this reason, in the perspective blurring processing, first, the alpha value of all the pixels is filled with 0xa0 (S201). Specifically, a polygon having the same size as the perspective projection plane 52 with the alpha value set to 0xa0 is converted into information (color information and Z information) other than the alpha value of the pixel at the drawing destination.
The value of the buffer is masked and drawn. next,
Set the alpha value to 0x90 for the pixels where Z3 ≧ Z
(S202). Specifically, a polygon having the same size as the perspective projection surface 52 in which the Z value is set to Z3 and the alpha value is set to 0x90 is converted into information other than the alpha value of the drawing destination pixel (color information and Z buffer Value) with masking. At this time, a depth test is used. Then, the alpha value of the pixel satisfying Z2 ≧ Z is filled with 0x80 (S20).
3) Subsequently, the alpha value of the pixel satisfying Z1 ≧ Z is filled with 0x70 (S204), and Z0 is further painted.
Pixels satisfying ≧ Z are filled with an alpha value of 0x60 (S205). The painting procedure is the same as in S201.

Next, the image on the VRAM in which the alpha value is set as described above is copied onto an output buffer provided on the VRAM (S206). In particular,
A polygon having the same size as the perspective projection surface 52 is written on the output buffer, and the image (formed on the input buffer of the VRAM) obtained in S201 to S205 is written to the output buffer as a texture.

Next, the microprocessor 14 instructs the image processing unit 16 to perform distant view blurring processing (S207, S207).
S208). The distant view blur processing includes the distant view 58 and the farthest view 5
The pixel representing the object arranged at 6 is targeted. Here, first, among the pixels drawn in the input buffer, an alpha test is performed, and the alpha value is 0x
Pixels belonging to 70 or less, that is, the pixels belonging to the distant view 58 and the farthest view 56 are shifted from the original position by one pixel to the left and right, and translucently combined with the image drawn in the output buffer (S207). That is, first, translucent synthesis is performed by shifting one pixel to the left, and then translucent synthesis is performed by shifting one pixel to the right. At this time, an appropriate value is set in advance for each translucency so as to reproduce a natural blurred taste. At the time of this translucent composition, a destination alpha test is performed so that pixels having an alpha value of 0x80 or more do not translucently combine pixels belonging to the distant view 58 and the farthest view 56. In this way, the pixels belonging to the distant view 58 and the farthest view 56 are the latest view 64, the near view 62, and the depth of focus 60.
, So that it is not translucent to the pixels belonging to, and a natural bokeh can be reproduced.

After that, among the pixels drawn in the input buffer, an alpha test is performed, and the alpha value becomes 0.
x60 or less, that is, pixels belonging to the farthest view 56 are shifted up and down by one pixel from the original position one by one and translucently synthesized with the image drawn in the output buffer (S20).
8). That is, translucent synthesis is performed by shifting one pixel to the upper side, and then translucently synthesized by shifting one pixel to the lower side. Also at this time, each translucency is set to an appropriate value in advance so as to reproduce a natural blur. Also, a destination alpha test was performed and the alpha value was 0x8
Pixels belonging to the farthest scene 56 are not translucently combined with pixels of 0 or more.

In this way, the translucent composition of the pixels belonging to the distant view 58 and the farthest view 56 is shifted one pixel to the left and right, and the translucent composition of the pixels belonging to the farthest view 56 is further shifted one pixel up and down. Can be implemented. In this manner, the blur of the pixels belonging to the farthest view 56 can be made larger than that of the far view 58.

Thereafter, the microprocessor 14 instructs the image processing unit 16 to perform a foreground blurring process (S20).
9, S210). The foreground blur processing is performed on pixels representing objects arranged in the foreground 62 and the latest landscape 64. Here, among the pixels drawn in the input buffer, an alpha test is first performed, and those having an alpha value of 0x90 or more, that is, the near view 62 and the latest view 64 are performed.
Are shifted from the original position by one pixel to the left and right, and translucently combined with the image drawn in the output buffer (S209). That is, first, translucent synthesis is performed by shifting one pixel to the left, and then translucent synthesis is performed by shifting one pixel to the right. At this time, an appropriate value is set in advance for each translucency so as to reproduce a natural blurred taste.

Thereafter, among the pixels drawn in the input buffer, an alpha test is performed, and the alpha value becomes 0.
Xa0 or more, that is, pixels belonging to the latest scenery 64 are shifted up and down by one pixel from the original position one by one and translucently synthesized with the image drawn in the output buffer (S21).
0). That is, translucent synthesis is performed by shifting one pixel to the upper side, and then translucently synthesized by shifting one pixel to the lower side. Also at this time, each translucency is set to an appropriate value in advance so as to reproduce a natural blur.

In this way, the translucent composition of the pixels belonging to the foreground 62 and the latest scene 64 is shifted by one pixel to the left and right, and the translucent composition of the pixels belonging to the latest scene 64 is further shifted one pixel up and down. Can be implemented. In this way, the blur of pixels belonging to the latest view 64 can be made larger than that of the near view 62.

Thereafter, the image drawn in the output buffer is supplied to the monitor 18 at a predetermined timing, where the image is displayed.

According to the game apparatus 10 described above, the pixels belonging to the depth of focus 60 are not subjected to the blurring process, and the other pixels can be subjected to the blurring process in accordance with the degree of departure from the depth of focus. In other words, the blur increases from the depth of focus 60 to the depth side, and increases from the depth of focus 60 to the near side. Also, a destination alpha test is performed to prevent pixels belonging to the distant view 58 and the farthest view 56 from being translucently combined with pixels belonging to the near side thereof. The blur processing can be performed.

The present invention is not limited to the above embodiment.

For example, in the above description, the destination alpha test is performed, and the distant view 58 and the farthest view 5 are executed.
6 belong to the front side, in particular, the depth of focus 60
Is not translucent to pixels belonging to
Instead of performing the destination alpha test, a depth of focus of 6
Pixels belonging to 0 may be drawn over the corresponding pixels of the image formed on the output buffer.

In the above description, the distant view 58 and the farthest view 5
6 and farthest view 5
Although the blur of 6 is increased, the blur is increased as the distance from the focal depth 60 is increased by changing the translucent rate or by changing the amount of pixel shift when performing translucent composition. Is also good. Foreground 62 and Recent 64
The same applies to the case of. In other words, by performing translucent composition in a manner corresponding to the Z value, that is, in a mode in which various parameters such as the number of translucent compositions, direction, translucency, pixel shift amount, and the like are made different according to the Z value, natural It is possible to achieve a soft taste.

Although the above description is of an example in which the present invention is implemented using the home game machine 11, the present invention can be similarly applied to arcade game machines. In this case, it is desirable to use a higher-speed storage device instead of the DVD 25 and the DVD reproducing unit 24, and to integrally form the monitor 18 and the speaker 22.

In the above description, the DVD 25 storing the game program and the game data is used in the home game machine 11. However, the information storage medium storing the game program and the game data, such as a personal computer, is read. Any computer capable of performing information processing based on the read content can be used.

The present invention is not limited to image processing relating to a game, but is applicable to any three-dimensional image processing. For example, the present invention is applicable to a three-dimensional CG animation, a flight simulator, a drive simulator, and the like.

Further, in the above description, the game program and the game data are supplied from the DVD 25 as the information storage medium to the home game machine 11, but the game program and the game data are distributed to the home or the like via the communication network. You can also. FIG. 7 is a diagram showing an overall configuration of a game program distribution system using a communication network. The program distribution device and method according to the present invention will be described with reference to FIG. As shown in FIG. 1, the game program distribution system 100 includes a game database 102, a server 104, a communication network 10
6. Personal computer 108, home game console 110, PDA
(Portable information terminal) 112. Among them, the game database 102 and the server 104 constitute a game program distribution device 114. The communication network 106 is, for example, the Internet or a cable television network. In this system, the game database 102 stores game programs and game data similar to the storage contents of the DVD 25. And
PC 108, home game console 110 or PDA 11
When the consumer makes a game distribution request using the communication network 106, the request is sent to the server 10 via the communication network 106.
It is conveyed to 4. Then, the server 104 reads the game program and the game data from the game database 102 in response to the game distribution request, and
8. Transmit to the game distribution request source such as the home game machine 110 or PDA 112. Here, the game distribution is performed in response to the game distribution request, but the server 104 may unilaterally transmit the game. Also, it is not always necessary to distribute all the game programs and game data necessary for realizing the game at once, and a necessary portion may be distributed according to the game phase. By distributing the game via the communication network 106 in this way, the consumer can easily obtain the game program and the game data.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of a game device according to an embodiment of the present invention.

FIG. 2 is a diagram illustrating an example of a game screen.

FIG. 3 is a diagram illustrating a game device according to the embodiment of the present invention;
FIG. 9 is a flowchart illustrating a two-dimensional image synthesis process.

FIG. 4 is a flowchart illustrating a perspective blurring process in the game device according to the embodiment of the present invention.

FIG. 5 is a flowchart illustrating a perspective blurring process in the game device according to the embodiment of the present invention.

FIG. 6 is a diagram illustrating a setting rule of depth range information (alpha value).

FIG. 7 is a diagram showing an overall configuration of a game program distribution system according to another embodiment of the present invention.

[Explanation of symbols]

10 game device, 11,110 home game machine, 1
2 buses, 14 microprocessors, 16 image processing units, 18 monitors, 20 audio processing units, 22 speakers,
24 DVD playback unit, 25 DVD, 26 main memory, 3
0 input / output processing unit, 32 controller, 40 car object, 42 mountain object, 44 grass object, 46 house object, 50 viewpoint, 52 perspective projection plane, 100 game program distribution system, 1
02 game database, 104 server, 106
Communication network, 108 PC, 112 PD
A, 114 Game program distribution device.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) // H04N 13/04 H04N 13/04 5C082 9A001 (72) Inventor Michio Horikiri 3-chome, Kanda Jimbocho, Chiyoda-ku, Tokyo No. 25 Konami Computer Entertainment Inc. Tokyo F-term (reference) 2C001 BC00 BC06 BC10 CB01 CB02 CB03 CB06 CC02 CC08 5B080 FA03 FA08 FA17 GA02 GA25 5C023 AA07 AA38 BA02 BA11 CA02 DA04 DA08 EA03 5C061 AA21 BA12 AB21 EC21 GA01 GA26 HA02 JA01 KC11 KD06 KE02 KE07 KE16 KM11 LA02 5C082 AA06 AA37 BA43 CA55 CA56 CA59 DA87 MM10 9A001 HH29 JJ76 KK45

Claims (7)

[Claims] 1. A display image storage means for storing color information and depth information of each pixel forming a display image, and converting the color information of each pixel into the color information of another pixel in a mode corresponding to the depth information. 3. A three-dimensional image synthesizing apparatus, comprising: 2. The three-dimensional image synthesizing apparatus according to claim 1, wherein the blur processing unit includes a depth range information setting unit that sets depth range information for each pixel based on the depth information. A three-dimensional image synthesizing apparatus, wherein the color information of each pixel is semi-transparently synthesized with the color information of another pixel in a mode corresponding to the depth range information set by a setting unit. 3. The three-dimensional image synthesizing device according to claim 1, wherein the blur processing unit is configured such that each pixel is located on a depth side of a predetermined focal depth in a virtual three-dimensional space based on the depth information. First pixel determining means for determining whether or not the pixel is a depth pixel representing an object to be reproduced, and a focus pixel representing an object located within a predetermined focal depth in a virtual three-dimensional space based on the depth information. A second pixel determination unit that determines whether or not the color information of the back pixel is translucent at least with respect to the color information of the focus pixel. Means, and a three-dimensional image synthesizing apparatus, characterized by comprising: 4. A step of storing color information and depth information of each pixel forming a display image, and half-changing the color information of each pixel with respect to the color information of another pixel in a mode corresponding to the depth information. Transparent synthesizing; and a three-dimensional image synthesizing method. 5. A step of storing color information and depth information of each pixel constituting a display image, and half-changing the color information of each pixel with respect to the color information of another pixel in a mode corresponding to the depth information. An information storage medium storing a program for causing a computer to execute: 6. A step of storing color information and depth information of each pixel constituting a display image, and half-changing the color information of each pixel with respect to the color information of another pixel in a manner corresponding to the depth information. A program distributing device that distributes a program for causing a computer to execute: 7. A step of storing color information and depth information of each pixel forming a display image, and half-changing the color information of each pixel with respect to the color information of another pixel in a mode corresponding to the depth information. A program distributing method for distributing a program for causing a computer to execute: