JP4413634B2 - PROGRAM, INFORMATION STORAGE MEDIUM, AND GAME DEVICE - Google Patents

Description

  The present invention relates to a program for causing a computer to realize a function of generating an image expressing a lens flare of a virtual camera.

One of the important elements in computer graphics is the expression of lens flare. Lens flare is a phenomenon in which an illusion of a lens shape or a diaphragm shape is generated due to repeated reflection of incident light within a lens barrel under the condition where strong light is incident on the lens. For example, in the case of shooting conditions in which a building is looked up against a clear sky, bright illusions such as a ring shape, a circle, and a hexagon appear intermittently from the sun.
When producing computer graphics, this lens flare is often added to the screen as a means for enhancing the power and reality, or as a means for easily showing the situation.

  As a technology for realizing lens flare expression by computer graphics, for example, an inner product of a line-of-sight vector of a virtual camera arranged in a three-dimensional virtual space and a vector connecting the position of the virtual camera and the position of the light source is a predetermined threshold value. In some cases, a ring-shaped polygon model that expresses flare with transparency in proportion to the inner product value is drawn (for example, see Patent Document 1).

In addition, there is a technique in which a plurality of light beam objects are subordinately arranged around a circular light source body, and the texture of the light source is mapped to an object aggregate composed of the light source body and the light beam (for example, patents). Reference 2). Specifically, first, the visible portion of the light source body is obtained from the depth information of the light source body portion. Even if the light source appears and disappears like a sunbeams by setting the texture information α channel corresponding to this visible part and the hidden part other than the light beam subordinate to this visible part, Lens flare can be expressed so that there is no failure of the relationship.
Japanese Patent No. 3415416 JP 2001-84393 A

  By using the conventional technology as described above, the lens flare can be expressed realistically. However, since a large amount of arithmetic processing is required, it has been a heavy burden for practical use in a game machine that requires high-speed processing. Therefore, for example, in a video game such as a flight simulation game in which the sun is frequently reflected on the screen, it is difficult to always express the lens flare by a conventional method because of processing speed.

  The present invention has been made in view of such a current situation, and an object thereof is to realize a lens flare expression realistically in a simple manner in computer graphics.

  In order to solve the above problems, a first invention is a program for causing a computer to generate an image of the three-dimensional virtual space photographed by the virtual camera by performing projection conversion processing of the three-dimensional virtual space into a camera coordinate system. And light source setting means for setting a light source in the three-dimensional virtual space (for example, the game calculation unit 22 and game stage information 722 in FIG. 3), and the location of light spots based on the position of the light source on the camera coordinate system. Bright spot image generating means (for example, the lens flare synthesis unit 25 in FIG. 3, steps S10 to S12 in FIG. 6) that generates a bright spot image (for example, the bright spot image P2 in FIG. 2) by arranging the image group, Filter means (for example, the lens flare synthesizing unit 2 in FIG. 3) that expresses partial color information of the bright spot image by performing predetermined filter processing on the bright spot image generated by the bright spot image generating means. , Steps S4 to S6 and S14 in FIG. 6, and a synthesis unit (for example, the lens flare synthesis unit 25 in FIG. 3) that synthesizes the bright spot image whose color information is expressed by the filter unit with the image in the three-dimensional virtual space. 6, the computer is caused to function as an image representing the lens flare of the virtual camera by the synthesis of the synthesis means.

  According to a seventh aspect of the present invention, there is provided a game apparatus for executing a given game by generating an image of the three-dimensional virtual space photographed by the virtual camera by projecting the three-dimensional virtual space into a camera coordinate system. (For example, the home game device 1200 of FIG. 1), which is a light source setting means for setting a light source in the three-dimensional virtual space (for example, the control unit 1211 of FIG. 1, the game calculation unit 22 of FIG. 3, game stage information). 722) and bright spot image generation means (for example, the control unit 1211 in FIG. 1 or FIG. 3) that generates a bright spot image by arranging a group of bright spots based on the position of the light source on the camera coordinate system. The lens flare synthesis unit 25, steps S10 to S12 in FIG. 6 and the bright spot image generated by the bright spot image generating means are subjected to a predetermined filter process to obtain partial color information of the bright spot image. table Filter means (for example, the control unit 1211 in FIG. 1, the lens flare synthesis unit 25 in FIG. 3, steps S4 to S6, S14 in FIG. 6), and the bright spot image in which color information is expressed by the filter means Combining means (for example, the control unit 1211 in FIG. 1, the lens flare combining unit 25 in FIG. 3, step S16 in FIG. 6) for combining with the image in the three-dimensional virtual space, An image representing lens flare of a virtual camera is generated.

  According to the first or seventh invention, based on the position of the light source set in the three-dimensional virtual space, a bright spot image in which a group of bright spot images to be a flare is arranged is generated. Only partial color information of the bright spot image can be expressed by a predetermined filtering process, and can be synthesized with the image in the three-dimensional virtual space. If you look at the lens flare in detail, the part of the characteristic shape that reminisces the structure of the lens (for example, the circular shape of the lens or the polygon of the aperture) (for example, the portion along the contour) appears as a particularly bright illusion. There are many cases. Therefore, by expressing only partial color information in the bright spot image, the expression of lens flare can be realized in a simple manner. For example, if a portion along the predetermined direction (for example, a portion along the contour) in the bright spot image that is the origin of the flare is expressed by filtering along the predetermined direction. Realistic lens flare having a characteristic shape can be expressed by simple filter processing.

  A second invention is the program of the first invention, wherein the bright spot image generating means is bright along a straight line connecting a position of the light source on the camera coordinate system and a visual field center position of the virtual camera. A program that causes the computer to function to generate a bright spot image by arranging a spot image group and changing a placement interval according to a distance between the position of the light source on the camera coordinate system and the center of the field of view. It is.

  According to the second invention, the same effect as that of the first invention is achieved, and a bright spot image is arranged along a straight line connecting the position of the light source reflected in the camera to the visual field center position of the virtual camera, that is, the screen center. In addition, the arrangement interval can be changed according to the distance of the light source from the center of the screen. Therefore, it is possible to simply express the characteristics of the lens flare that is generated in a continuous manner from the light source and whose interval regularly changes according to the position of the light source.

  3rd invention is the program of 1st or 2nd invention, Comprising: The said filter means is a filter image (for example, filter image P1 of FIG. 2) by which the polygonal body or the annular body was drawn concentrically, and said A program for causing the computer to function so as to display color information of the bright spot image in a direction along the outline of the feature drawn in the filter image by filtering the bright spot image.

  According to the third invention, the same effect as that of the first or second invention is achieved, and the filter processing is performed on the basis of an image in which a plurality of polygons or annular bodies are drawn concentrically, and the shape drawn in this image The color information of the bright spot image can be expressed in the direction along the outline of the image. Therefore, the lens flare can be expressed in a characteristic shape resulting from the lens structure.

  4th invention is the program of 3rd invention, Comprising: The said filter means changes the said concentric position according to the position of the said light source on the said camera coordinate system, and performs the said filter process A program for causing a computer to function.

For example, in the case of an actual lens flare, the position of the lens flare that draws a large arc appears to be shifted from the center of the screen as the light source appears at a position farther from the center of the screen.
According to the fourth invention, the same effect as the third invention can be obtained, and the light source position can be moved by changing the display position of the color information of the bright spot image according to the position of the light source reflected on the camera. The regular change of the lens flare due to the accompanying lens structure can be expressed more realistically.

  5th invention is a program of any one invention of 1st-4th, Comprising: The said filter means changes the grade of the color information of the said bright spot image to expose according to the brightness of the said light source This is a program that causes the computer to function so as to include degree changing means (for example, the lens flare synthesis unit 25 in FIG. 3 and steps S6 and S14 in FIG. 6).

  According to the fifth invention, the same effect as any one of the first to fourth inventions can be obtained, and the degree of color information of the bright spot image can be changed according to the brightness of the light source. The brightness can be changed.

  A sixth invention is a computer-readable information storage medium storing the program of any one of the first to fifth inventions.

  The “information storage medium” here refers to a computer that can read information, such as a CD-ROM, MO, memory card, DVD, hard disk, IC memory, etc., and its connection form is detachable from the apparatus. It may be connected to the apparatus via a communication line, and the form is not limited. Therefore, according to the sixth invention, the computer can exhibit the same effect as any one of the first to fifth inventions.

  According to the present invention, based on the position of the light source set in the three-dimensional virtual space, a bright spot image in which a group of bright spot images to be a flare is arranged is generated, and the bright spot image is aligned along a predetermined direction. Filter processing can be performed. And by this filter process, the color information of the part along the said predetermined direction among the bright spot images can be expressed, and it can synthesize | combine with the image of a three-dimensional virtual space. That is, it is possible to express a lens flare having a characteristic shape by a simple filter process such as exposing a portion along a predetermined direction reminiscent of the lens structure in the bright spot image that is the origin of the flare. it can.

  Then, a bright spot image is arranged along a straight line connecting the position of the light source reflected on the camera to the visual field center position of the virtual camera, that is, the center of the screen, and the arrangement interval is changed according to the distance from the light source center of the screen. By doing so, it is possible to simply express the characteristics of the lens flare that is generated in a continuous manner from the light source and whose interval regularly changes according to the position of the light source.

  Furthermore, if filtering is performed based on an image in which a plurality of polygons or annular bodies are concentrically drawn, color information of a bright spot image is displayed in a direction along the contour of the shape drawn in the image. Therefore, the lens flare can be expressed with a characteristic shape resulting from the lens structure.

  In addition, by changing the display position of the color information of the bright spot image according to the position of the light source reflected on the camera, the regular position change of the lens flare caused by the lens structure accompanying the movement of the light source position is more realistic. If the degree of color information of the bright spot image is changed according to the brightness of the light source, the brightness of the lens flare can be changed.

  As a best mode for carrying out the present invention, a case where a flight simulation game is executed in a consumer game machine and lens flare caused by sunlight is expressed will be described as an example. The “lens flare” referred to in the present embodiment is a phantom generated by repeated reflection of incident light in the lens barrel under the condition where strong light is incident on the lens, and is a so-called “ghost”. An illusion arranged linearly from the light source reflected on the screen.

[Description of configuration]
FIG. 1 is a diagram showing an example of the configuration of a consumer game device to which the present invention is applied. As shown in the figure, the consumer game device 1200 includes a game controller 1202, a main body device 1210, and a display 1220 having a speaker 1222. The game controller 1202 is connected to the main device 1210, and the display 1220 is connected to the main device 1210 by a cable 1201 capable of transmitting image signals, sound signals, and the like.

  The game controller 1202 includes direction keys 1204 and button switches 1206 for the player to input game operations and screen display positions, and outputs operation input signals to the main body device 1210.

  The main unit 1210 includes, for example, a control unit 1211 equipped with a CPU and IC memories, and a reading device for an information storage medium such as a CD-ROM 1212, game information read from the CD-ROM 1212, operation signals from the game controller 1202, and the like. Based on the above, various game processes are calculated to generate image signals of game screens and sound signals of game sounds. The “game information” here refers to information according to a program used for processing by an electronic computer (computer) such as a game device.

  The main body device 1210 uses a part of the IC memory mounted on the control unit 1211 as a frame buffer, performs projection conversion processing on an image photographed from a virtual camera arranged in a three-dimensional virtual space, to a camera coordinate system, A game image is generated by drawing (storing) on the frame buffer. Then, an image signal and an audio signal are output to the display 1220, a game image is displayed on the display 1220, and a game sound is output from the speaker 1222. The player can enjoy the game by operating the game controller 1202 while watching the game screen displayed on the display 1220.

Game information including programs and data necessary for the main body device 1210 to execute game processing is stored in, for example, a CD-ROM 1212, an IC memory 1214, a memory card 1216, etc., which are information storage media detachable from the main body device 1210. Stored. Alternatively, the game information is connected to the communication line 2 via the communication device 1218 provided in the main body device 1210, and the game information is downloaded and acquired from an external device (for example, a game server).
The “communication line” here refers to a communication path through which data can be exchanged. That is, the communication line 2 is meant to include a communication network such as a telephone communication network, a cable network, and the Internet in addition to a LAN using a dedicated line (dedicated cable) or Ethernet (registered trademark) for direct connection. The communication method is meaning regardless of wired / wireless.

[Description of the principle of lens flare expression]
FIG. 2 is a conceptual diagram for explaining the principle of lens flare expression in the present embodiment. In the present embodiment, the lens flare is not expressed by a polygon model. As shown in FIG. 5A, after drawing an image taken from a virtual camera arranged in a three-dimensional virtual space on the RGB channel of the frame buffer for drawing the game screen, concentric light and darkness is drawn on the alpha channel. A filter image P1 that is an image (gray image) is drawn.

  Focusing on one bright ring in the filter image P1, the center is set to be brightest and gradually darken toward the inside and outside. Such a ring is set so that the width of the brighter portion is gradually narrowed toward the outer ring and the entire ring is gradually darkened, and is drawn concentrically in layers. Of course, as a variety of expressions, the outer edge of each ring may not be gradually darkened but may have a clear border of black and white, and the shape of light and dark is not necessarily formed by multiple rings. The configuration is not limited, and a plurality of intermittent arcs may be arranged to result in substantially concentric light and dark. Further, a polygon may be used instead of the ring.

  Next, as shown in FIG. 4B, separately, along the straight line connecting the position of the light source L in the screen (the position of the light source in the camera coordinate system) and the screen center position (the visual field center position), the light source L A light spot image P2 is generated in which a light source texture that expresses the above and an image of bright spots M (M1 to M5) that are the basis of the lens flare expression are arranged according to a predetermined rule. The bright spot image P2 is, for example, an image in which the light source L and the bright spot M are drawn on a black background. One bright spot M forms a substantially circular or polygonal shape in which the center is brightest and darker toward the outside, and the size and the color thereof are appropriately set by imitating an actual lens flare. The same applies to the rules of arrangement of the light spots M.

  Next, as shown in FIG. 5C, based on the alpha value stored in the alpha channel of the frame buffer, that is, the value of the concentric filter image P1 stored earlier, the bright part is made opaque and dark. The bright spot image P2 is filtered by alpha synthesis (alpha blending) with the portion made transparent, and color information is expressed. Then, the processing result (result image P3) is added and combined with the RGB channels and rendered.

  As a result, the bright spot M portion applied to the dark portion of the filter image P1 is added and synthesized on the image photographed by the virtual camera with transparency according to the alpha value, and the bright spot M applied to the bright portion of the filter image P1. The portion is masked and not added and synthesized. Therefore, for example, a portion along the concentric ring in the bright spot image P2 is rendered as a bright spot or arc in the image stored in the RGB channel, and is reflected as if in the lens barrel. It is drawn like a phantom. The lens flare can be expressed by simple filter processing without performing complicated calculations as in the prior art.

  In addition, the lens flare according to the prior art has been expressed as a phantom with a clear geometric shape because it is expressed by a polygon model. However, the lens flare expressed by this embodiment has a soft outline. The lens flare has a new appearance that has a feeling of blurring of light that is different from the conventional one.

[Description of functional block]
FIG. 3 is a functional block diagram illustrating an example of a functional configuration according to the present embodiment. As shown in the figure, a consumer game device 1200 includes an operation input unit 10 that receives operations from a player, a processing unit 20 that executes various arithmetic processes related to device control and game control, and a game screen. An image display unit 30 for display output, a sound output unit 40 for outputting game sounds, a communication unit 50 for realizing data communication with an external device via a communication line, and a storage unit 70 for storing various programs and data. With.

  The operation input unit 10 is realized by, for example, a button switch, a lever, a dial, a mouse, a keyboard, and various sensors, and outputs an operation input signal corresponding to an operation by the player to the processing unit 20. In this embodiment, the game controller 1202 of FIG.

  The processing unit 20 performs various arithmetic processes such as control of the entire home game device 1200 and game calculations. The function is realized by hardware such as a CPU (CISC type, RISC type), ASIC (gate array, etc.), IC memory, and related control programs. In FIG. 1, the control unit 1211 included in the main body apparatus 1210 corresponds.

  The processing unit 20 also includes a game calculation unit 22 that mainly performs calculation processing related to the game, generation of an image in a virtual space from the viewpoint of the virtual camera from various data obtained by the processing of the game calculation unit 22, and a game It includes an image generation unit 24 that generates an image signal for displaying a screen, a sound generation unit 26 that generates game sounds such as sound effects and BGM, and a communication control unit 28 that performs control related to data communication. .

  The game calculation unit 22 executes various game processes for executing a flight simulation game based on an operation input signal from the operation input unit 10 and a program and data read from the storage unit 70. For example, placement processing of objects such as virtual cameras and fighters in a three-dimensional virtual space, background object movement and deformation processing, object intersection determination processing (hit check processing), menu selection processing, game results (results) Calculation, various data storage / read processing, and the like are executed.

  The image generation unit 24 is realized, for example, by an arithmetic device such as a CPU or DSP, a control program thereof, a drawing frame IC memory such as a frame buffer, and the like. The image generation unit 24 performs a geometric transformation process and a shading process based on the calculation result of the game calculation unit 22 to generate a 3DCG image for displaying the game screen, and an image signal of the generated image is displayed on the image display unit. Output to 30. In the present embodiment, a lens flare synthesis unit 25 that executes processing related to drawing of the lens flare is provided.

  The lens flare composition unit 25 draws a concentric filter image P1 on the alpha channel of the frame buffer, and a light spot image P2 in which the light source L and the light spot M that is the basis of the expression of the lens flare are arranged. A process for generating, a filter process for alpha-blending the generated bright spot image P2 based on an alpha value stored in the alpha channel of the frame buffer, and a process for adding and synthesizing the alpha-blended result image P3 to the RGB channel are executed. .

  Then, the image display unit 30 is based on the image signal obtained by adding and synthesizing the result image P3, which is alpha-blended from the image generation unit 24, to the RGB channel of the frame buffer. The game screen is displayed while redrawing. The image display unit 30 can be realized by a display device such as a CRT, LCD, ELD, PDP, or HMD, for example. In the example of FIG. 1, the display 1220 corresponds.

  The sound generation unit 26 is realized by, for example, an arithmetic device such as a CPU or DSP and its control program, generates sound such as sound effects and BGM used during the game, and generates a sound signal of the generated sound as a sound output unit 40. Output to.

  The sound output unit 40 is a device for outputting sound effects, BGM, and the like based on the sound signal from the sound generation unit 26, and corresponds to the speaker 1222 in the example of FIG.

  The communication unit 50 connects to the communication line 2 and performs data communication with an external device in accordance with a control signal from the communication control unit 28. For example, it is realized by a wireless communication module, a modem, TA, a cable communication cable jack or a control circuit. The communication device 1218 in FIG. 1 corresponds to this. Note that information related to protocols and the like provided by the communication unit 50 during communication is stored in, for example, the storage unit 70 and is appropriately read and used.

  The storage unit 70 is a system program (not shown) for realizing various functions for causing the processing unit 20 to control the home game device 1200 in an integrated manner, and game information including programs and data necessary for executing the game. 72 etc. are memorized. Further, the processing unit 20 temporarily stores various programs and data necessary for the arithmetic processing. The function can be realized by an information storage medium such as various IC memories, memory cards, hard disks, CD-ROMs, MOs, and DVDs. In the example of FIG. 1, a CD-ROM 1212, an IC memory 1214, and a memory card 1216 correspond.

  The game information 72 includes a program and data for causing the processing unit 20 to function as the game calculation unit 22. Particularly in the present embodiment, a lens flare synthesis program 720 for causing the image generation unit 24 to function as the lens flare synthesis unit 25, and a game stage for storing information such as background, appearance characters, and clear conditions for configuring the game stage. Information 722, bright spot initial setting information 726 for storing initial setting values of each bright spot M arranged when generating the bright spot image P2, an initial filter image 728 that is the basis of the filter image P1, and the virtual camera And virtual camera setting information 729 for storing current setting values such as the arrangement position, orientation, and angle of view.

  In the present embodiment, since the object of expressing the lens flare is the sun, the game stage information 722 includes light source position information 724 that is the position of the sun, and a light source texture 725 that expresses the brightness of the light source L (specific light source: the sun) alone. Is stored. The texture includes, for example, a white circle that represents the solar body and a radial light bulb that shows the spread of light around the white circle.

  FIG. 4 is a diagram illustrating an example of a data configuration of the bright spot initial setting information 726 in the present embodiment. As shown in FIG. 6A, the bright spot initial setting information 726 corresponds to the identification information 726a, the bright spot pattern 726b, and the initial arrangement distance 726c for each bright spot that is the basis of the expression of the lens flare. It is attached and stored.

  The bright spot pattern 726b is an image having a display color imitating a lens flare and having the center brightest and darker toward the outside, and the boundary with the background is blurred, as shown in FIG. For example, pale yellow or pale blue.

  The initial arrangement distance 726c is a linear distance ML (for example, the unit is a dot) from the center position of the light source L to the center position of the bright spot M on the screen, as shown in FIG. In the present embodiment, the initial arrangement distance 726c corresponds to the distance when the light source L appears on the diagonal vertex of the screen. The lens flare composition unit 25 then reduces the distance from the light source L to the bright spot M as the light source L approaches the center of the screen according to the distance from the position of the light source L in the screen to the center position of the screen. The light spot image P2 is generated by changing the initial arrangement distance 726c and arranging the light spots M. For example, under the condition that the light source L is reflected in the center of the screen, all the bright spots M are arranged on the light source L. In the drawing, the bright spots M are arranged only from the light source L toward the center of the screen. However, as seen in the actual lens flare phenomenon, some bright spots M are moved from the position of the light source L to the outside of the screen. Of course, it may be arranged facing.

  FIG. 5 is a diagram illustrating an example of the initial filter image 728 in the present embodiment. As shown in FIG. 5A, the initial filter image 728 is an image in which a white ring on a black background is drawn concentrically at the screen center point. As shown in FIG. 5B, when attention is paid to one bright ring, the center portion of the ring width is set to be brightest and gradually darken toward the inside and the outside. Such a ring is drawn concentrically, with the outer ring being set such that the brightest part at the center becomes thinner and darker as a whole.

The virtual camera setting information 729 stores information such as the current position, posture, and angle of view of the virtual camera that is movement-controlled by the game calculation unit 22, and is constantly rewritten during the game according to the player's operation. For example, when the virtual camera is set to a position where the airplane operated by the player is photographed from behind, the virtual camera follows the airplane as the position and posture of the airplane are changed according to the player's operation. Thus, the position and orientation are changed, and the virtual camera setting information 729 is updated. The angle of view is changed according to a viewpoint position switching operation or the like, for example, as in a conventional flight simulation game.
In this embodiment, since the lens flare is expressed by the sun, the position and orientation of the airplane changes, and the position and orientation of the virtual camera change accordingly, so that the sun often appears or disappears on the screen. become.

[Description of process flow]
Next, the flow of processing in the present embodiment will be described with reference to FIGS.
FIG. 6 is a flowchart for explaining the flow of processing relating to the drawing of the lens flare in the present embodiment. The processing described here is realized by the processing unit 20 reading and executing the lens flare synthesis program 720, and the game calculation unit 22 causes an airplane object, a light source, and a virtual camera in a three-dimensional virtual space. The three-dimensional virtual space image captured by the virtual camera by the image generation unit 24 is projected and converted to the camera coordinate system and rendered on the RGB channel of the frame buffer.

  First, the lens flare composition unit 25 displays on the screen whether or not the specific light source L (in this embodiment, the specific light source is the sun) falls within the field of view of the virtual camera, that is, the light source L expressing the lens flare. It is determined whether or not (step S2). Specifically, with reference to the virtual camera setting information 729, a field of view range (shooting distance infinite) is obtained from the current position, posture, and angle of view of the virtual camera, and the light source position information 724 is set in this field of view. Whether or not the position of the sun is included, that is, the specific light source L is clipped at an infinite shooting distance. Note that, by setting the reference range for determination in this step to be a range larger than the visual field range, it is possible to cause the lens flare to be reflected by strong incident light even if the specific light source L does not appear in the screen.

When it is determined that the specific light source L appears in the screen (step S2; YES), the distance from the position of the specific light source L in the screen to the screen center position (screen center) is obtained, and the screen center is determined according to this distance. The center position of the concentric circle of the filter image P1 is determined in the opposite direction across the sandwich (step S4), and drawing is performed on the alpha channel of the frame buffer so that the center of the concentric circle of the initial filter image 728 is aligned with the determined center position (step S6). ).
Specifically, for example, as shown in FIG. 7A, a predetermined coefficient C is multiplied to the ratio of the distance Lg from the specific light source to the center of the screen with respect to the half of the diagonal distance Ld of the screen. Thus, the distance L0 from the center of the screen to the center of the concentric circle of the filter image P1 is calculated. Therefore, in the case of FIG. 11A, the filter image P1 whose center is moved slightly to the lower left of the screen center is drawn on the alpha channel, as shown in FIG.

  Then, the lens flare synthesis unit 25 changes the entire alpha value of the alpha channel according to the apparent brightness of the specific light source L, for example, as in the relationship shown in FIG. 8 (step S8). Specifically, in the case of the sun in fine weather, the alpha value is left at the default setting, and in the case of a cloudy sun, the alpha value is changed to be smaller than the initial value by the amount of darkness separated by the clouds. The lens flare should be expressed slightly. Then, when the specific light source L is darker than a certain level (point Q in FIG. 8), it is determined that the light source is not bright enough to cause lens flare even when the light source appears in the screen, and the alpha value is set to all “0”. It is preferable that flare is not expressed.

Next, the lens flare synthesis unit 25 determines each arrangement position of the bright spots M according to the distance from the specific light source L in the screen to the center of the screen (step S10), and the position of the specific light source at the determined arrangement position. A bright spot image P2 in which bright spots M are added and synthesized on a black background along the straight line connecting the center of the screen is generated (step S12), and the generated bright spot image P2 is the alpha value changed in step S8. Alpha synthesis is performed with the filter image P1 (step S14).
Specifically, as shown in FIG. 9, the specific light source for the half of the diagonal distance Ld of the screen with respect to the initial arrangement distance 726 c of each bright spot set in the bright spot initial setting information 726. The ratio of the distance Lg from L to the center of the screen is multiplied to obtain the arrangement distance of the bright spots. For example, when the specific light source L is reflected at the diagonal vertex position of the screen, each bright spot M is arranged with the value of the initial arrangement distance 726c. When the specific light source L approaches the center of the screen, the arrangement distance is initially set to be smaller than the position distance 726c, and the interval between the light spots M is reduced, so that the entire screen approaches the center of the screen. When the specific light source L is reflected in the center of the screen, all the bright spots M are arranged at the center position of the screen as with the specific light source L. Then, the bright spot image P2 is alpha-synthesized based on the affa value stored in the alpha channel, and the synthesis result is stored in the alpha channel. Of course, the bright spot image P2 may be separately stored in a storage area other than the alpha channel.

Next, the lens flare synthesis unit 25 adds and synthesizes the synthesis result (result image P3) of the bright spot image P2 and the filter image P1 to the RGB channel of the frame buffer (step S16).
Therefore, in a flight simulation game, when the airplane turns and the sun enters the field of view, a bright arc shape is drawn on the RGB channel, and a bright illusion that is reflected in the lens barrel appears in the game screen. Drawn as if Since the present invention can express the lens flare by a simple method, the merit is more exhibited under the condition that the line-of-sight direction of the virtual camera changes relatively quickly and frequently like a flight simulation game.

[Hardware configuration]
Next, a hardware configuration capable of realizing the home game device 1200 will be described. FIG. 10 is a diagram illustrating an example of a hardware configuration according to the present embodiment. The home game apparatus 1200 includes a CPU 1000, a ROM 1002, a RAM 1004, an information storage medium 1006, a sound generation IC 1008, an image generation IC 1010, and I / O ports 1012 and 1014. Data input / output is connected.

  The CPU 1000 corresponds to the processing unit 20 in FIG. 3, and controls the entire apparatus according to a program stored in the information storage medium 1006, a system program stored in the ROM 1002, an operation input signal input by the control device 1022, and the like. And various data processing.

  The ROM 1002, the RAM 1004, and the information storage medium 1006 correspond to the storage unit 70 in FIG. The ROM 1002 corresponds to an IC memory mounted on the control unit 1211 of the main unit 1210 shown in FIG. 1, and stores programs and data related to control of the main unit 1210 such as system programs.

  The RAM 1004 is a storage means used as a work area of the CPU 1000 and stores the given contents of the information storage medium 1006 and the ROM 1002 or the calculation result of the CPU 1000.

  The information storage medium 1006 corresponds to the CD-ROM 1212, the IC memory 1214, and the memory card 1216 in FIG. 1, and stores the game information 72 in FIG. An information storage medium 1006 is realized by an IC memory card, a removable hard disk unit, an MO, a DVD-ROM, or the like, stores information stored in the ROM 1002, and appropriately reads and uses the information.

  The sound generation IC 1008 is an integrated circuit that generates game sounds such as sound effects and BGM based on information stored in the ROM 1002 and the information storage medium 1006, and the generated sounds are output by the speaker 1020. The speaker 1020 corresponds to the sound output unit 40 in FIG. 3 and the speaker 1222 in FIG.

  The image generation IC 1010 is an integrated circuit that generates pixel information for outputting an image to the display device 1018. The image generation unit 24 in FIG. 3 corresponds to this. The display device 1018 corresponds to the image display unit 30 in FIG. 3 and the display 1220 in FIG.

  A control device 1022 is connected to the I / O port 1012, and a communication device 1024 is connected to the I / O port 1014. The control device 1022 corresponds to the operation input unit 10 in FIG. 3 and the game controller 1202 in FIG. 1, and is a device for the player to input various game operations.

  The communication device 1024 exchanges various types of information used inside the game device with the outside. The communication device 1024 is connected to other game devices and transmits / receives given information according to the game program, via a communication line. Used to send and receive information such as game programs. This corresponds to the communication unit 50 in FIG. 3 and the communication device 1218 in FIG.

  Note that the processing performed by the image generation IC 1010, the sound generation IC 1008, and the like may be executed in software by the CPU 1000 or a general-purpose DSP.

  The present invention is not limited to the home game device 1200 shown in FIG. 1, but various devices such as a commercial game device, a portable game device, a general-purpose computer such as a personal computer, and a large attraction device in which a large number of players participate. The same applies to the above.

  For example, FIG. 11 is a diagram showing an example of an appearance when the present invention is applied to the arcade game apparatus 1300. As shown in the figure, the arcade game apparatus 1300 includes a display 1302 for displaying a game screen image, a speaker 1304 for outputting game sound effects and BGM, a joystick 1306 for inputting front and rear, left and right directions, and a push button 1308. And a control unit 1320 that controls the arcade game device 1300 in an integrated manner through arithmetic processing to execute a given game.

  The control unit 1320 includes an arithmetic processing unit such as a CPU 1324 and a ROM 1322 in which programs and data necessary for controlling the arcade game device 1300 and executing a game are stored. The CPU mounted on the control unit 1320 executes various processes by appropriately reading out programs and data from the ROM 1322 and performing arithmetic processing. Then, the player enjoys the game by inputting game operations from the joystick 1306 and the push button 1308 while viewing the game screen displayed on the display 1302.

  The present invention is not limited to a game executed by a stand-alone device, and may be applied to a game called a network game. As a system configuration for realizing a network game, for example, (1) a personal computer or a home game system installed in a home is used as a game terminal, and a server and a wired / wireless communication line such as an Internet network or a private line network are connected. Configuration to connect, (2) Configuration in which multiple game terminals are connected via a communication line without using a server, (3) Multiple game terminals are connected via a communication line, one of which is a server There are a configuration having a function, and (4) a configuration in which a plurality of game terminals are physically coupled to form a single system (for example, a business game system) as a whole.

[Description of modification]
As described above, the embodiments to which the present invention is applied have been described. However, the application of the present invention is not limited to these embodiments, and as long as the same actions and effects can be obtained without departing from the spirit of the invention, the components are appropriately selected. Additions, omissions, and changes may be made.

  For example, in the present embodiment, when the filter image P1 is generated, the initial filter image 728 stored in advance is drawn on the alpha channel. For example, the distance from the light source position in the screen to the screen center position is short. The initial filter image 728 may be reduced and then drawn on the alpha channel so that the radius of each ring becomes smaller. Alternatively, on the contrary, the initial filter image 728 may be enlarged so that the gap between the rings widens as the light source position moves away from the center of the screen, and then subjected to processing. In this case, it can be expressed that the drawing position of the arc-shaped lens flare changes depending on the position of the specific light source.

Alternatively, the lens flare synthesis unit 25 may directly draw each ring on the alpha channel of the frame buffer without referring to the initial filter image 728 in steps S4 to S6.
For example, the drawing is performed by shifting the center position of the outer ring according to the distance Lg from the specific light source L to the center of the screen. Also in this case, it can be expressed that the drawing position of the arc of the lens flare changes depending on the position of the specific light source. The direction in which the center position is shifted may be either the direction approaching the light source position or the direction away from the light source position, but it is preferable that the moving direction does not differ depending on the ring.

  In the present embodiment, the sun that can be placed in the flight simulation game is set as the specific light source, but the present invention is not limited to this. For example, in race games, action games, RPG games, etc., the same applies to light from lighthouses and searchlights, headlights from cars and motorcycles, laser light emitted from laser sights, reflected light from gems and mirrors, etc. be able to. Specifically, for example, when the light source moves like a headlight, the game calculation unit 22 obtains the position of the light source and the light projecting direction, and whether the light projecting from the light source is incident on the screen in step S2. It is determined whether or not, and a series of processes (steps S4 to S16) including generation of the filter image P1 is executed when the light is incident.

The figure which shows an example of a structure of the home game device to which this invention is applied. The conceptual diagram for demonstrating the principle of lens flare expression. The functional block diagram which shows an example of a function structure of the home game device to which this invention is applied. The figure which shows an example of the data structure of bright spot initial setting information. The figure which shows an example of an initial stage filter image. The flowchart for demonstrating the flow of the process concerning drawing of a lens flare. The conceptual diagram for demonstrating the calculation method of the center position of a filter image. The figure which shows an example of the change rate of the alpha value based on the brightness of a light source. The conceptual diagram for demonstrating the calculation method of the arrangement position of a bright spot. The figure which shows an example of the hardware constitutions for implement | achieving the consumer game device to which this invention is applied. The figure which shows an example of the external appearance at the time of applying this invention to a business use game device.

Explanation of symbols

DESCRIPTION OF SYMBOLS 20 Processing part 22 Game calculating part 24 Image generation part 25 Lens flare synthetic | combination part 70 Memory | storage part 72 Game information 720 Lens flare synthetic | combination program 722 Game stage information 724 Light source position information 725 Light source texture 726 Light spot initial setting information
726b Light spot pattern
726c Initial arrangement distance 728 Initial filter image 1200 Home-use game apparatus 1202 Game controller 1210 Main body apparatus 1211 Control unit L Light source (specific light source)
M Light spot P1 Filter image P2 Light spot image P3 Result image

Claims (8)

A program for causing a computer to generate an image of the three-dimensional virtual space captured by a virtual camera by projecting and transforming the three-dimensional virtual space into a camera coordinate system,
Light source setting means for setting a light source in the three-dimensional virtual space;
Bright spot image generating means for generating a bright spot image by arranging a group of bright spots based on the position of the light source on the camera coordinate system;
By filtering the bright spot image generated by the bright spot image generating means with a filter image in which a plurality of polygonal bodies or annular bodies are drawn concentrically, in the direction along the contour of the shape drawn in the filter image Filter means for displaying color information of the bright spot image ;
Synthesis means for synthesizing a bright spot image in which color information is expressed by the filter means with an image of the three-dimensional virtual space;
A program that causes the computer to function and generates an image expressing lens flare of the virtual camera by combining the combining means.   A program for causing a computer to generate an image of the three-dimensional virtual space captured by a virtual camera by projecting and transforming the three-dimensional virtual space into a camera coordinate system,
  Light source setting means for setting a light source in the three-dimensional virtual space;
  Bright spot image generating means for generating a bright spot image by arranging a group of bright spots based on the position of the light source on the camera coordinate system;
  By filtering the bright spot image generated by the bright spot image generating means with a filter image drawn by shifting the center position in ascending order of a plurality of polygonal bodies or annular bodies having different sizes, the filtered image Filter means for expressing color information of the bright spot image in a direction along the contour of the drawn feature;
  Synthesis means for synthesizing a bright spot image in which color information is expressed by the filter means with an image of the three-dimensional virtual space;
  A program that causes the computer to function and generates an image expressing lens flare of the virtual camera by combining the combining means. The bright spot image generating means arranges a bright spot image group along a straight line connecting the position of the light source on the camera coordinate system and the visual field center position of the virtual camera, and The program according to claim 1 or 2 for causing the computer to function so as to generate a bright spot image by changing an arrangement interval in accordance with a distance between a light source position and a visual field center position. It said filter means is any one of claims 1 to 3 for operating the computer to perform the filtering process by changing the position of the concentric in accordance with the position of the light source on the camera coordinate system The program described in. 5. The method according to claim 1 , wherein the filter means causes the computer to perform the filtering process by changing the alpha value according to the brightness of the light source and synthesizing the bright spot image with alpha. A program according to any one of the above.   The computer-readable information storage medium which memorize | stored the program as described in any one of Claims 1-5. A game device for performing a given game by generating an image of the three-dimensional virtual space captured by a virtual camera by projecting and transforming the three-dimensional virtual space into a camera coordinate system,
Light source setting means for setting a light source in the three-dimensional virtual space;
A bright spot image generating means for generating a bright spot image by arranging a group of bright spots based on the position of the light source on the camera coordinate system;
By filtering the bright spot image generated by the bright spot image generating means with a filter image in which a plurality of polygonal bodies or annular bodies are drawn concentrically, in the direction along the contour of the shape drawn in the filter image Filter means for expressing color information of the bright spot image ;
Synthesis means for synthesizing a bright spot image in which color information is expressed by the filter means with an image of the three-dimensional virtual space;
And a game apparatus that generates an image expressing lens flare of the virtual camera by the synthesis of the synthesis means.   A game device for performing a given game by generating an image of the three-dimensional virtual space captured by a virtual camera by projecting and transforming the three-dimensional virtual space into a camera coordinate system,
  Light source setting means for setting a light source in the three-dimensional virtual space;
  A bright spot image generating means for generating a bright spot image by arranging a group of bright spots based on the position of the light source on the camera coordinate system;
  By filtering the bright spot image generated by the bright spot image generating means with a filter image drawn by shifting the center position in ascending order of a plurality of polygonal bodies or annular bodies having different sizes, the filtered image Filter means for expressing color information of the bright spot image in a direction along the contour of the drawn feature;
  Synthesis means for synthesizing a bright spot image in which color information is expressed by the filter means with an image of the three-dimensional virtual space;
  And a game apparatus that generates an image expressing lens flare of the virtual camera by the synthesis of the synthesis means.