JP2006318388A - Program, information storage medium, and image generation system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a program, an information storage medium, and an image generation system capable of reliably reflecting the effect of filter processing even on reflection of a moving object.
When a reflection event in which a moving object POB is reflected on a water surface object WOB, which is a translucent object to be filtered, occurs, the moving object POB is flipped with respect to a given reference plane. The mirror image object MOB corresponding to the moving object POB is arranged and set at a position in the object space, and after the moving object POB and the mirror image object MOB are drawn, the original image on which the water surface object WOB is drawn is filtered.
[Selection] Figure 4

Description

  The present invention relates to a program, an information storage medium, and an image generation system.

  Conventionally, an image generation system (game system) that generates an image that can be seen from a virtual camera (a given viewpoint) in an object space that is a virtual three-dimensional space is known. Popular. Taking an image generation system capable of enjoying a role-playing game (RPG) as an example, a player operates a player character (player object), which is his or her own character, to move it on a map in the object space, and to create an enemy character. Enjoy the game by playing against (enemy objects), interacting with other characters, and visiting various towns.

  In such an image generation system, when expressing fluctuations (ripple waves) on the water surface, the image once drawn (original image) is further processed to create an image with an atmosphere different from the original image. A post filter method (post effect method) is used. For example, the fluctuation of the water surface can be expressed by a fluctuation filter process that distorts the original image over time. By the way, when expressing such fluctuations in the water surface, it is preferable that the character existing at the water surface is reflected in the water surface, and the effect of the post filter is surely displayed in the reflected image of the character. The technology that can be reflected in is desired. In particular, when the character is a moving object, the position in the object space changes from moment to moment, so it is desirable to perform a reflection expression that matches the state of the change.

  The present invention has been made in view of the above circumstances, and provides a program, an information storage medium, and an image generation system that can surely reflect the effect of filter processing on the reflection of a moving object. It is in.

  The present invention is an image generation system for generating an image viewed from a virtual camera in an object space, and whether or not a reflection event occurs in which a moving object is reflected on a translucent object to be filtered. An event determination unit for determining the mirror object of the moving object at a position where the moving object is flipped with respect to a given reference plane when it is determined that the reflection event has occurred. An image generation system including: a mirror image object setting unit configured to place an image; and a drawing unit that performs a filtering process on an original image on which the translucent object is drawn after drawing the moving object and the mirror image object. . The present invention also relates to a program that causes a computer to function as each of the above-described units. The present invention also relates to an information storage medium that can be read by a computer and stores (records) a program that causes the computer to function as each of the above-described units.

  The computer refers to a physical device (system) having basic components such as a processor (processing unit: CPU or GPU), a memory (storage unit), an input device, and an output device. The same applies to the following.

  According to the present invention, after drawing a moving object and a mirror image object corresponding to the moving object, a translucent object to be filtered is drawn. Therefore, even when additional processing such as mirror object placement and drawing is performed, an image in which the effect of the filtering process is reliably reflected in the mirror image of the moving object reflected in the translucent object Can be generated.

  In the image generation system, the program, and the information storage medium of the present invention, a virtual reflecting surface object corresponding to the semi-transparent object is arranged and set in the object space, and the event determination unit calculates the visual vector of the virtual camera. It may be determined whether or not the reflection event has occurred by performing an intersection determination between the reflection line-of-sight vector reflected by the virtual reflection surface object and the moving object. By doing this, it is possible to specify in advance the range in which the moving object reflection event occurs according to the size of the virtual reflecting surface object.

  In the image generation system, the program, and the information storage medium of the present invention, a virtual reflecting surface object corresponding to the semitransparent object is arranged and set in the object space, and the event determination unit includes the moving object. A bounding volume is set, and a determination is made as to whether or not the reflection event has occurred by performing an intersection determination between the reflected line-of-sight vector obtained by reflecting the line-of-sight vector of the virtual camera with the virtual reflecting surface object and the bounding volume. You may do it. In this way, it is possible to easily determine whether or not a moving object reflection event occurs.

  In the image generation system, the program, and the information storage medium of the present invention, the virtual reflection surface object is divided into a plurality of primitive surfaces, and the event determination unit does not reflect the reflection surface for primitive surfaces that do not intersect the line-of-sight vector. The line-of-sight vector calculation process may be omitted. In this way, the processing can be speeded up when the arrangement setting range of the virtual reflecting surface object is wide.

  In the image generation system, the program, and the information storage medium of the present invention, the drawing unit draws the translucent object with an α value different from that of the object group including the moving object and the mirror image object. Filter processing may be performed on the image using the α value set in the plane as mask information. In this way, the moving object is not affected by the filtering process, and only the mirror image object reflected in the translucent object can generate an image affected by the filtering process.

  In the image generation system, the program, and the information storage medium of the present invention, the drawing unit masks only the drawing area of the translucent object in the original image by using the α value set in the α plane of the original image as mask information. The copied work image may be generated, a filter image may be generated based on the work image, and the filter processing for combining the original image and the filter image may be performed. In this way, it is possible to easily perform local glare expression and the like by performing blurring processing only on the portion that needs to be filtered.

  In the image generation system, the program, and the information storage medium of the present invention, the drawing unit generates a filter image based on a work image obtained by copying the original image, and only the drawing region of the translucent object is included in the filter image. May be combined with the original image using the α value set in the α plane of the original image as mask information. For example, in filter processing that requires color information of all pixels of the original image, such as pixel replacement processing, if the color information around the drawing area of a semi-transparent object is lost, it is unnatural as if it is mixed with noise. An image is generated. Therefore, after the pixel replacement process is performed on the work image obtained by copying the entire original image, the filter image and the original image are synthesized only for the drawing area of the semi-transparent object. You can prevent natural situations.

  In the image generation system of the present invention, the virtual camera control unit that controls the virtual camera based on given control information, and the position, direction, and angle of view of the virtual camera based on the control information of the virtual camera. And a parameter setting unit that changes a filter strength parameter of the filtering process when it is determined that at least one has changed. In the program and information storage medium of the present invention, the computer may function as the virtual camera control unit and the parameter setting unit. In this way, the filter strength parameter is changed when it is determined that at least one of the position, direction, and angle of view of the virtual camera has changed, so the degree of influence of the filtering process on the original image is adjusted appropriately. can do. For this reason, it can prevent that the image after a filter process becomes unnatural with a bad appearance, and can produce a high quality image | video.

  In the image generation system, program, and information storage medium of the present invention, a gazing point of the virtual camera is set for the moving object, and the parameter setting unit moves the moving object in the object space. Thus, when the gazing point of the virtual camera moves, the filter strength parameter may be changed according to the moving distance. In this way, the filter strength parameter may be changed only when the mobile object to be noticed moves in the object space, so that the processing becomes simple.

  Hereinafter, this embodiment will be described. In addition, this embodiment demonstrated below does not unduly limit the content of this invention described in the claim. In addition, all the configurations described in the present embodiment are not necessarily essential configuration requirements of the present invention.

1. Configuration FIG. 1 shows an example of a functional block diagram of an image generation system (game system) of the present embodiment. Note that the image generation system of the present embodiment may have a configuration in which some of the components (each unit) in FIG. 1 are omitted.

  The operation unit 160 is for a player to input operation data of a player object (an example of a moving object, a player character operated by the player), and functions thereof are a lever, a button, a steering, a microphone, and a touch panel display. Alternatively, it can be realized by a housing or the like. The storage unit 170 serves as a work area for the processing unit 100, the communication unit 196, and the like, and its function can be realized by a RAM (VRAM) or the like.

  The information storage medium 180 (computer-readable medium) stores programs, data, and the like, and functions as an optical disk (CD, DVD), magneto-optical disk (MO), magnetic disk, hard disk, and magnetic tape. Alternatively, it can be realized by a memory (ROM). The processing unit 100 performs various processes of the present embodiment based on a program (data) stored in the information storage medium 180. That is, the information storage medium 180 stores a program for causing a computer to function as each unit of the present embodiment (a program for causing a computer to execute processing of each unit).

  The display unit 190 outputs an image generated according to the present embodiment, and its function can be realized by a CRT, LCD, touch panel display, HMD (head mounted display), or the like. The sound output unit 192 outputs the sound generated by the present embodiment, and its function can be realized by a speaker, headphones, or the like.

  The portable information storage device 194 stores player personal data, game save data, and the like. Examples of the portable information storage device 194 include a memory card and a portable game device. The communication unit 196 performs various controls for communicating with the outside (for example, a host device or other image generation system), and functions thereof are hardware such as various processors or communication ASICs, programs, and the like. It can be realized by.

  Note that a program (data) for causing a computer to function as each unit of this embodiment is distributed from the information storage medium of the host device (server) to the information storage medium 180 (storage unit 170) via the network and communication unit 196. May be. Use of the information storage medium of such a host device (server) can also be included in the scope of the present invention.

  The processing unit 100 (processor) performs processing such as game processing, image generation processing, or sound generation processing based on operation data and programs from the operation unit 160. Here, as the game process, a process for starting a game when a game start condition is satisfied, a process for advancing the game, a process for placing an object such as a character or a map, a process for displaying an object, and a game result are calculated. There is a process or a process of ending a game when a game end condition is satisfied. The processing unit 100 performs various processes using the main storage unit 171 in the storage unit 170 as a work area. The functions of the processing unit 100 can be realized by hardware such as various processors (CPU, DSP, etc.), ASIC (gate array, etc.), and programs.

  The processing unit 100 includes an object space setting unit 110, a movement / motion processing unit 112, a virtual camera control unit 114, a parameter setting unit 116, a drawing unit 120, and a sound generation unit 130. Note that some of these may be omitted.

  The object space setting unit 110 is an object composed of various objects (polygons, free-form surfaces, subdivision surfaces, etc.) representing display objects such as characters, buildings, stadiums, cars, trees, pillars, walls, and maps (terrain). ) Is set in the object space. In other words, the position and rotation angle of the object in the world coordinate system (synonymous with direction and direction) are determined, and the rotation angle (rotation angle around the X, Y, and Z axes) is determined at that position (X, Y, Z). Arrange objects.

  The object space setting unit 110 includes a mirror image object setting unit 111.

  The mirror image object setting unit 111 is arranged on an object space in which a moving object is flipped with respect to a given reference plane when a reflection event occurs in which the moving object is reflected on a translucent object to be filtered. The mirror image object of the moving object is placed at the position.

  The movement / motion processing unit 112 performs a movement / motion calculation (movement / motion simulation) of an object (such as a character, a car, or an airplane). That is, based on operation data input by the player through the operation unit 160, a program (movement / motion algorithm), various data (motion data), or the like, the object is moved in the object space, or the object is moved (motion, animation). ) Is performed. Specifically, object movement information (position, rotation angle, speed, or acceleration) and motion information (position or rotation angle of each part that constitutes the object) are sequentially transmitted every frame (1/60 seconds). Perform the required simulation process. A frame is a unit of time for performing object movement / motion processing (simulation processing) and image generation processing.

  The virtual camera control unit 114 performs a virtual camera (viewpoint) control process for generating an image viewed from a given (arbitrary) viewpoint in the object space. Specifically, processing for controlling the position (X, Y, Z) or rotation angle (rotation angle about the X, Y, Z axis) of the virtual camera (processing for controlling the viewpoint position, the line-of-sight direction or the angle of view) I do.

  For example, when an object (eg, character, ball, car) is photographed from behind using a virtual camera, the position or rotation angle of the virtual camera (the direction of the virtual camera is set so that the virtual camera follows changes in the position or rotation of the object. ) To control. In this case, the virtual camera can be controlled based on information such as the position, rotation angle, or speed of the object obtained by the movement / motion processing unit 112. Alternatively, the virtual camera may be controlled to rotate at a predetermined rotation angle or to move along a predetermined movement path. In this case, the virtual camera is controlled based on the virtual camera data for specifying the position (movement path) or rotation angle of the virtual camera. When there are a plurality of virtual cameras (viewpoints), the above control process is performed for each virtual camera.

  The virtual camera control unit 114 controls the position (viewpoint position), the direction (gaze direction), the angle of view, and the like based on given control information. Various information such as virtual camera position, direction, angle of view change information, gazing point movement information (movement distance, movement direction), object movement information and rotation information, or operation information of the operation unit 160 are stored. Control information can be arbitrarily determined. For example, when the movement information of the gazing point is used as the control information of the virtual camera, when the position of the gazing point is changed in the object space, the movement distance and movement direction, in other words, the world coordinates (X, The viewpoint position (position), line-of-sight direction (direction), angle of view, etc. of the virtual camera can be controlled in accordance with changes in Y, Z). Note that the movement information of the gazing point in a broad sense includes not only the change information of the position coordinates of the gazing point in the world coordinate system, but also the position coordinates of the gazing point in the camera coordinate system (view point coordinate system) and the screen coordinate system. Also includes change information. In addition, the gazing point of the virtual camera can be set in association with the object. For example, in a system in which a moving object can be moved or operated in the object space based on operation information of the operation unit 160. An arbitrary representative point (for example, center coordinates) of the moving object can be set as the gazing point. In this case, the point of interest moves following the movement or movement of the moving object, and as a result, the position, direction, angle of view, etc. of the virtual camera are controlled so as to follow the movement of the moving object. Will be.

  The event determination unit 116 determines whether or not a reflection event has occurred in which the moving object is reflected on the translucent object to be filtered.

  Specifically, it is determined whether or not a reflection event has occurred by performing an intersection determination between a reflected line-of-sight vector obtained by reflecting the line-of-sight vector of a virtual camera with a virtual reflecting surface object and a moving object.

  Further, the event determination unit 116 sets a bounding volume (bounding box, bounding sphere, cylinder, quadrangular pyramid, etc.) that includes the moving object instead of performing the intersection determination between the reflected line-of-sight vector and the moving object. It is also possible to determine whether or not a reflection event has occurred by determining whether the bounding volume and the reflection line-of-sight vector intersect. In this way, processing can be simplified.

  Further, the virtual reflection surface object may be divided into a plurality of primitive surfaces. In this case, the event determination unit 116 omits the calculation process of the reflection line-of-sight vector for the primitive surface that does not intersect the line-of-sight vector. can do. In this way, it is not necessary to perform the reflection line-of-sight vector calculation processing routine for all the primitive surfaces, so that the processing speed can be increased.

  The parameter setting unit 118 performs a process of setting a filter strength parameter that determines the degree of influence of the filter process. In particular, based on the control information of the virtual camera, at least one of the position, direction, and angle of view of the virtual camera has changed. If it is determined, a process for changing the filter strength parameter of the filter process is performed. For example, the filter strength parameter can be changed when it is determined that at least one of the position, direction, and angle of view of the virtual camera has changed based on the moving distance information of the gazing point of the virtual camera. When a gazing point is set for a moving object, when the moving object moves in the object space and the gazing point of the virtual camera moves, a filter strength parameter is set according to the moving distance. May be changed.

  Here, when performing a filter process including a pixel replacement process as an example of the filter process, the filter strength parameter can be changed so that the pixel replacement distance in the pixel replacement process is reduced. For example, when the pixel replacement process is a process in which the pixel replacement distance is determined based on the periodic function, the parameter changing process for decreasing the amplitude component parameter of the periodic function or increasing the frequency component parameter may be performed. it can. The pixel replacement process is a process of replacing the color information of the Kth pixel with the color information of the Lth pixel according to a given rule, and the pixel replacement distance is the difference between the Kth pixel and the Lth pixel. It is the displacement (distance) between them. In the pixel replacement process, there may be pixels in which pixel replacement does not occur, and the color information of a certain pixel may be replaced as the color information of a plurality of pixels.

  Further, the filter strength parameter changing process can control whether or not the filter strength parameter is permitted based on the relationship between the moving distance of the gazing point of the virtual camera and a preset threshold value. In this way, it can be prevented that the filter strength parameter is frequently changed to deteriorate the appearance of the image. Specifically, when the moving distance of the gazing point of the virtual camera is greater than a given threshold, the process of continuously bringing the filter strength parameter from the first level to the second level lower than the first level It can be performed. In this case, it is preferable to change the filter strength parameter so as to gradually approach the second level from the first level. In addition, when the moving distance of the gazing point of the virtual camera once exceeds the threshold value and then changes to fall below the threshold value, processing for returning the filter strength parameter from the second level to the first level is performed. Can do. Also in this case, it is preferable to continuously change the filter strength parameter from the second level toward the first level.

  The drawing unit 120 performs drawing processing based on the results of various processing (game processing) performed by the processing unit 100, thereby generating an image and outputting the image to the display unit 190. In the case of generating a so-called three-dimensional game image, first, geometric processing such as coordinate transformation (world coordinate transformation, camera coordinate transformation), clipping processing, or perspective transformation is performed, and drawing data ( Primitive vertex position coordinates, texture coordinates, color data, normal vector, α value, etc.) are created. Based on the drawing data (object data), an object (one or a plurality of primitives) after perspective transformation (after geometry processing) is imaged in units of pixels such as a drawing buffer 172 (frame buffer or intermediate buffer (work buffer)). Draw in a buffer (VRAM) that can store information. Thereby, an image that can be seen from the virtual camera (given viewpoint) in the object space is generated. In addition, when there are a plurality of virtual cameras (viewpoints), the drawing process can be performed so that an image seen from each virtual camera can be displayed as a divided image on one screen.

  The drawing unit 120 performs geometry processing, texture mapping, hidden surface removal processing, α blending, and the like as drawing processing.

  In the geometry processing, processing such as coordinate transformation, clipping processing, perspective transformation, or light source calculation is performed on the object. Then, object data (positional coordinates of object vertices, texture coordinates, color data, normal vector, α value, etc.) after geometry processing (after perspective transformation) is stored in the main storage unit 172.

  Texture mapping is a process for mapping a texture (texel value) stored in the texture storage unit 176 to an object. Specifically, the texture (surface properties such as color and α value) is read from the texture storage unit 176 using texture coordinates or the like set (given) to the vertex of the object. Then, a texture that is a two-dimensional image is mapped to an object. In this case, bilinear interpolation or the like is performed as processing for associating pixels with texels or texel interpolation.

  In this embodiment, texture mapping can also be performed using a color lookup table (CLUT) for index color / texture mapping stored in the LUT storage unit 175 as texture mapping. In this case, an index texture in which a number (color) determined based on the relative position of each pixel of the original image or the relative position of each pixel of the divided block obtained by dividing the original image is set as an index number (index color) is used. While referring to a color lookup table that associates index numbers with image information (R component, G component, B component, A component (α component)), virtual objects (display screen size polygons, divided block size polygons) ) Texture mapping. When performing pixel replacement processing, prepare an index texture to replace the index number assigned to each texel of the index texture corresponding to the original image or the divided block of the original image, and use the color lookup table for the index texture. A pixel replacement image (filter image) can be generated by texture mapping to a virtual object while referring to the image.

  As the hidden surface removal processing, hidden surface removal processing may be performed by a Z buffer method (depth comparison method, Z test) using a Z buffer 178 (depth buffer) in which a Z value (depth information) of a drawing pixel is stored. it can. That is, when the drawing pixel corresponding to the primitive of the object is drawn, the Z value stored in the Z buffer 174 is referred to. Then, the Z value of the referenced Z buffer 174 is compared with the Z value at the drawing pixel of the primitive, and the Z value at the drawing pixel is the front side when viewed from the virtual camera (for example, a small Z value). If it is, the drawing process of the drawing pixel is performed and the Z value of the Z buffer 174 is updated to a new Z value.

  As the α blending, a translucent synthesis process (usually α blending, addition α blending, subtraction α blending, or the like) based on the α value (A value) is performed. For example, in the case of normal α blending, the following processes (1) to (3) are performed.

R _Q = (1−α) × R ₁ + α × R ₂ (1)
G _Q = (1−α) × G ₁ + α × G ₂ (2)
B _Q = (1−α) × B ₁ + α × B ₂ (3)
In addition, in the case of addition α blending, the following expressions (4) to (6) are performed. In the case of simple addition, α = 1 and the following formulas (4) to (6) are performed.

R _Q = R ₁ + α × R ₂ (4)
G _Q = G ₁ + α × G ₂ (5)
B _Q = B ₁ + α × B ₂ (6)
In the case of subtractive α blending, the processing of the following equations (7) to (9) is performed. In the case of simple subtraction, α = 1 and the following formulas (7) to (9) are processed.

R _Q = R ₁ −α × R ₂ (7)
G _Q = G ₁ −α × G ₂ (8)
B _Q = B ₁ −α × B ₂ (9)
Here, R ₁ , G ₁ , B ₁ are RGB components of an image (original image) already drawn in the drawing buffer 172, and R ₂ , G ₂ , B ₂ should be drawn in the drawing buffer 172. This is the RGB component of the image. R _Q , G _Q , and B _Q are RGB components of an image obtained by α blending. The α value is information that can be stored in association with each pixel (texel, dot), for example, plus alpha information other than color information. The α value can be used as mask information, translucency (equivalent to transparency and opacity), bump information, and the like.

  In the present embodiment, the drawing unit 120 performs a filtering process on the original image on which the translucent object is drawn after drawing the moving object and the mirror image object. As filter processing, blurring processing, pixel replacement processing, and the like can be performed. At that time, a filter image corresponding to the original image is generated, and the original image and the filter image are combined to filter the original image. Processing can be performed. As a synthesis method of the original image and the filter image, there are α blending (usually α blending, addition α blending, subtraction α blending) and translucent drawing using an α test.

  In the present embodiment, the drawing unit 120 draws the translucent object with an α value different from that of the object group including the moving object and the mirror image object. The drawing unit 120 can perform a filtering process using the α value set in the α plane of the original image as mask information. As a result, it is possible to generate an image in which the effect of the filter processing is added only to a given drawing area of the original image. That is, partial filter processing can be performed on the original image.

  As a technique for rendering the α value set in the α plane of the original image to be mask information, the α component of the vertex color of the semi-transparent object is set to α ≧ α1, and other objects (moving object) , Mirror image object, etc.) by setting the α component of the vertex color of the vertex to α <α1, setting α ≧ α1 on the α plane of the texture mapped to the translucent object, and other objects (moving object) , A method of setting α <α1 in the α plane of the texture mapped to the mirror image object, or the α component of the vertex color of the semitransparent object and the α plane of the texture for the semitransparent object The value α obtained by multiplying the α value is set so that α ≧ α1, and the vertex color α of another object (moving object, mirror image object, etc.) Min, there is a method such that a value obtained by multiplying the set alpha values alpha plane texture for other objects is set such that alpha <[alpha] 1. When the mask information is set in the α component of the vertex color of the object, the object data is stored in the object data storage unit 176. When the mask information is set for the α plane of the texture, the texture mapped to the object is stored in the texture storage unit 173.

  The drawing unit 120 switches the usage of the mask information (α value) set in the α plane of the original image in accordance with the content of the filter processing.

  For example, when performing filter processing including first blur processing (first filter processing), only the drawing area of the translucent object in the original image is copied using the α value set in the α plane of the original image as mask information. The work image is generated, a filter image is generated based on the work image, and the original image and the filter image are synthesized.

  Also, for example, when performing filter processing (second filter processing) including pixel replacement processing, a filter image is generated based on a work image obtained by copying the entire original image, and a translucent object is drawn in the filter image. Only the region is combined with the original image using the α value set in the α plane of the original image as mask information.

  The sound generation unit 130 performs sound processing based on the results of various processes performed by the processing unit 100, generates game sounds such as BGM, sound effects, or sounds, and outputs the game sounds to the sound output unit 192.

  Note that the image generation system of the present embodiment may be a system dedicated to the single player mode in which only one player can play, or may be a system having a multiplayer mode in which a plurality of players can play. Further, when a plurality of players play, game images and game sounds to be provided to the plurality of players may be generated using one terminal, or connected via a network (transmission line, communication line) or the like. Alternatively, it may be generated by distributed processing using a plurality of terminals (game machine, mobile phone).

  Next, the method of this embodiment will be described with reference to the drawings. In the following description, the case where the method of the present embodiment is employed with respect to the filter processing for expressing glare or the filter processing for expressing fluctuations such as ripples will be mainly described. It can be applied not only to such filter processing but also to various filter processing.

2.1 Mirror Image Object Placement Setting Method In the present embodiment, when a reflection event occurs in which a moving object is reflected on a translucent object to be filtered, the moving object is set with respect to a given reference plane. A method is adopted in which the mirror image object of the moving object is set in the object space at the flipped position. Below, as shown in FIG. 2, the case where the terrain object GOB, the mobile object POB, and the water surface object WOB are set in the object space will be described as an example. In the object space shown in FIG. 2, the moving object POB can freely move on the terrain object GOB, and the water surface object WOB is arranged as a translucent object. That is, when the moving body object POB moves to the water surface expressed by the water surface object WOB, an event (reflection event) in which the moving body object POB is reflected on the water surface object WOB occurs. Note that the method of the present embodiment can be applied not only to reflection on the water surface but also to reflection on marble, reflection on a mirror, and the like.

  In the present embodiment, as shown in FIG. 3A, whether or not a reflection event occurs is determined by using a virtual reflecting surface object ROB and a bounding volume Vlm containing the moving object POB and a line-of-sight vector Vc of the virtual camera VC. This is done by determining the intersection with the reflected line-of-sight vector Vr. If it is determined that the reflected line-of-sight vector Vr intersects the bounding volume Vlm, the moving object POB is flipped with respect to a given reference plane, and the mirror image object MOB corresponding to the moving object is placed at the flipped position. Placement is set. In this case, the reference surface can be, for example, a surface (extension surface) on the extension of the surface of the virtual reflection surface object ROB.

  The virtual reflection surface object ROB is composed of a plurality of rectangular (rectangular, square) primitive surfaces, and is arranged in a boundary region (border) between the water surface object WOB and the terrain object GOB. That is, the virtual reflecting surface object ROB is arranged so as to overlap with a partial area of the water surface object WOB in an area where the moving object POB may be reflected. Note that the virtual reflection surface object is handled as an object that is placed and set in the object space but is not drawn.

  The bounding volume Vlm for determining the intersection of the reflection line-of-sight vector Vr is a spherical bounding sphere. Instead of the bounding sphere, a bounding box, a cylinder, a quadrangular pyramid, or the like that encloses the moving object POB may be set.

  Then, for example, as shown in FIG. 3B, the intersection d between the reflected line-of-sight vector Vr and the bounding sphere (bounding volume Vlm) is determined by the distance d between the extended line segment of the reflected line-of-sight vector Vr and the center C of the bounding sphere. When the radius is shorter than the radius r of the bounding sphere (d <r), it is determined that the two intersect each other, and it can be determined that the reflection of the moving object on the translucent object occurs. Further, for example, as shown in FIG. 3C, when the distance d between the extension line segment of the reflection line-of-sight vector Vr and the center C of the bounding sphere is longer than the radius r of the bounding sphere (d> r), both Can be determined not to intersect. In the present embodiment, it is possible to easily determine whether or not a reflection event of the moving object POB occurs in this way. It should be noted that the intersection between the reflected line-of-sight vector Vr and the object (object) may not be detected for an object farther than a certain distance from the virtual camera VC (viewpoint).

  If it is determined that a reflection event of the moving object POB occurs, the mirror object MOB is arranged and drawn at the position where the moving object POB is flipped. The arrangement setting of the mirror image object MOB is a matrix Mfa × Mo obtained by multiplying the local matrix Mo of the moving object POB and the flip matrix Mfa for flipping the object perpendicular to the reference plane as the local matrix Mr of the mirror image object MOB. This can be realized by performing coordinate transformation on the world coordinate system.

  Note that an object (fixed object) that is fixedly arranged in the object space can be arranged in advance by flipping it to a mirror surface position (a position flipped with respect to a reference surface). Since the moving object POB can move in the object space, the mirror image object MOB cannot be fixedly arranged in advance. Therefore, the reflection is determined each time as in this embodiment, and the mirror image object MOB is arranged. It is necessary to make settings. Further, since the mirror image object MOB is a 3D object in which the moving object POB is arranged and set by local matrix conversion, it can be moved according to the movement of the moving object POB.

  The virtual reflection surface object ROB can be composed of a plurality of primitive surfaces. For primitive surfaces that do not have an intersection with the line-of-sight vector from the virtual camera VC, the calculation processing of the reflection line-of-sight vector Vr is omitted, and the processing load Can be lightened. Further, it may be possible to permit / deny the reflection for each object arranged in the object space. Even in this case, it is possible to omit the intersection determination with the reflection line-of-sight vector Vr for an object that is not permitted (an object that is not permitted to be reflected).

2.2 Filtering Method of the Present Embodiment In the present embodiment, the α value set in the α plane of the original image as shown in FIG. By selectively filtering the drawing area of the water surface object WOB, as shown in FIG. 4 (B) or FIG. 4 (C), the moving object POB reflected in the water surface object WOB which is a translucent object is displayed. A filter technique that generates an image reflecting the effect of the filter processing is also applied to the mirror image object MOB. In FIG. 4B, a fluctuation filter process is performed, and in FIG. 4C, a glare filter process is performed.

* Fluctuation Filter Method FIGS. 5A to 5C show a filter image generation process when the fluctuation filter process is performed.

  Specifically, as shown in FIGS. 5A and 5B, when generating the original image (FIG. 5B) to be filtered, the mirror image object MOB of the moving object POB is drawn. Then, the water surface object WOB is drawn. Also, the water surface object (filter processing target object) WOB (α = α1) to be filtered is drawn with an α value different from the terrain object GOB (α = α2) and the moving object POB (α = α3). Yes. As shown in FIG. 5A, the mirror image object MOB is initially drawn with an α value (α = α3) similar to that of the moving object POB. However, as shown in FIG. 5B, the water surface object WOB Is drawn, the α value is overwritten by the α value of the water surface object WOB (α = α1) in the region where the water surface object WOB and the mirror image object MOB overlap and are drawn.

  In the present embodiment, the filter image shown in FIG. 5C is synthesized (semi-transparent drawing) only in the region where α ≧ α1 by the α test, as shown in FIG. It is possible to generate an image in which the filtering process is performed only on the drawing area of the water surface object WOB including the mirror image object MOB to be filtered. In the example shown in FIGS. 5A and 5B, an α value serving as mask information is set in the α component (A component) of the vertex color of the object. That is, the mask information is obtained from the object data after the geometry processing. As described above, in the fluctuation filter method of the present embodiment, the mask information can be drawn on the α plane of the original image only by drawing the water surface object WOB that is a semi-transparent object subjected to geometry processing.

  In the present embodiment, the filter image shown in FIG. 5C is generated by performing pixel replacement processing on the work image. At this time, a pixel replacement process in which the pixel replacement distance fluctuates periodically is performed using an index color / texture mapping technique.

  Specifically, as shown by A1 in FIG. 6, a filter image (filter filter) generated by dividing the original image drawn in the drawing buffer into a plurality of divided blocks and performing pixel replacement processing in units of the divided blocks. A filtering process is performed to synthesize (semi-transparent drawing) the image of the processed object) with the original image.

  At this time, each divided block has a size of, for example, 16 × 16 pixels, and can be handled as a color lookup table in which these 256 pixels are indexed based on their relative positions, as shown by A2 in FIG. . Further, as indicated by A3 in FIG. 6, a shift table in which the position of each pixel of the divided block is shifted can be prepared separately from the color lookup table (CLUT), and the shift table can be handled as an index texture. In the shift table, the index number determined based on the relative position of the pixel of the divided block is handled as the coordinate value of the pixel in the divided block, and the index number of the pixel shifted by the pixel replacement distance ΔY is set for each pixel.

  Then, as indicated by A4 in FIG. 6, with reference to the color look-up table, texture mapping is performed on the index texture set based on the shift table for the polygon (virtual object) having the divided block size. Then, as shown by A5 in FIG. 6, a polygon having a divided block size obtained by texture mapping the index texture is drawn at a corresponding position in the original image. By doing in this way, the process which replaces the pixel of an original image is realizable. These processes can be performed on all the divided blocks to generate a filter image corresponding to the original image. Finally, as shown by A6 in FIG. 6, a filter process for applying a post-effect to the original image can be performed by synthesizing the filter image with the original image.

  By the way, in this embodiment, the filter image shown in FIG. 5C in which pixel replacement is performed is created in the work buffer. At this time, it is preferable to copy the entire original image drawn in the frame buffer to the work buffer. In contrast to this, there is a method of partial copying in which only the drawing area of the water surface object WOB is drawn in the work buffer. However, in this case, color information other than the drawing area of the water surface object WOB is lost. If pixels are replaced in this state, an unnatural color protrusion appears in the filter image. For this reason, by copying the entire original image of the frame buffer to the work buffer and performing pixel replacement processing on the copy image (work image) to generate a filter image, an unnatural color in the filter image is generated. The inconvenience that the protrusion appears can be avoided.

* Glare Filter Method FIGS. 7A to 7C show a filter image generation process when glare filter processing is performed.

  First, as shown in FIG. 7A, when an object existing in a scene (view volume) seen from a virtual camera arranged in the object space is drawn in a frame buffer, a translucent object to be filtered is used. The drawing area of a certain water surface object WOB is drawn with α1, the terrain object GOB is drawn with α2 having a value smaller than α1, and the moving object POB is also drawn with α3 having a value smaller than α1. In the drawing area where the mirror image object MOB corresponding to the moving object POB and the water surface object WOB overlap, the α value is rewritten to α1 when the water surface object WOB is drawn. In the example shown in FIG. 7A, an α value serving as mask information is set in the α component (A component) of the vertex color of the object. That is, the mask information is obtained from the object data after the geometry processing.

  When the glare filter is applied to the original image drawn in the frame buffer, as shown in FIG. 7B, an α test is performed using the α value set in the α plane of the original image as mask information, Only the drawing area of α ≧ α1 is reduced and copied to a work buffer smaller in size than the frame buffer. At this time, the image information in the work buffer must be cleared (filled in black). In the example shown in FIG. 7A, since α ≧ α1 is only the drawing area including the water surface object WOB and the mirror image object MOB to be filtered, as shown in FIG. In addition, only the drawing area including the water surface object WOB and the mirror image object MOB is reduced and copied. Then, by performing color extraction processing and blurring processing on the image (work image) reduced and copied to the work buffer, a filter image for glare expression can be generated as shown in FIG.

  Here, as the color extraction process, a process is performed in which a color brighter than the reference color is extracted from each pixel of the work image and the color information of the difference is obtained. For example, as shown in B1 of FIG. 8, a single-color virtual polygon (single-color polygon) in which the reference color C1 is set to the vertex color is prepared, and the single-color polygon is drawn in the work buffer in a translucent manner. Thus, as shown in B2 of FIG. 8, if the color of an arbitrary pixel P of the work image is C2, the color of the pixel P of the color extraction image created in the work buffer after rendering the monochrome polygon subtracted and translucent. Becomes C2-C1. That is, in the color extraction image, a color darker than the reference color is clamped to black, and a lighter color than the reference color is a difference color. Thus, by obtaining only colors brighter than a certain reference color, it is possible to specify an area where glare is likely to occur.

  In addition, as blurring processing, each image can be blurred by repeating the reduction and enlargement of the image to interpolate the color information of each pixel using the bilinear filter method, or by performing texture mapping while shifting the texture coordinates using the bilinear filter method. There is a method of blurring an image by interpolating pixel color information. The blurring processing method is not limited to the above, and various methods can be employed. For example, the method of blurring an image by texture mapping using the bilinear filter method is to set the work image of the work buffer as a texture as shown in D1 of FIG. 9, and shift the texture coordinates to a virtual polygon of the work buffer size. It is realized by mapping. For example, as shown in D2 of FIG. 9, the texture coordinates are shifted in the X direction (horizontal direction) and the texture based on the work image is texture-mapped to the virtual polygon, or the texture coordinates are changed as shown in D3 of FIG. By shifting the texture based on the work image to the virtual polygon by shifting in the Y direction (vertical direction), the color information of each pixel of the work buffer is interpolated by the bilinear filter method, and the image becomes blurred. At this time, by repeatedly performing the process shown in D2 and the process shown in D3 in FIG. 9, the degree of blurring of the image can be further increased.

  In the glare filter method of this embodiment, the filter image shown in FIG. 7C created in the work buffer by performing color extraction processing and blurring processing on the work image is the source of the frame buffer shown in FIG. By adding and synthesizing to the image, it is possible to generate an image as shown in FIG. 4C in which glare processing is performed only in the vicinity of the drawing region including the water surface object WOB and the mirror image object MOB in the original image. it can. Note that the addition synthesis of the original image and the filter image can be performed by addition α blending. In addition, if the glare filter method of the present embodiment is performed by normal α blending for the method of combining the original image and the filter image, it can be applied to soft focus expression by filter processing.

2.3 Filter Strength Parameter Setting Method In this embodiment, when it is determined that at least one of the viewpoint position, line-of-sight direction, and angle of view of the virtual camera has changed, that is, the virtual camera is moved, rotated, zoomed, or When panning or the like, a method of changing the setting of the filter strength parameter of the filter processing is adopted.

  Here, when the filter processing of this embodiment includes pixel replacement processing, the pixel replacement distance ΔY in the pixel replacement processing is set based on a periodic function as shown in FIG. That is, the shift table set in the index texture is rewritten according to the periodically changing pixel replacement distance ΔY. A plurality of index textures in which the pixel replacement distance ΔY is periodically changed may be prepared in advance. The periodic function is represented by the following formula (A).

ΔY = Asin (ωt + f (x, y)) (A)
As shown in FIG. 10, A is an amplitude component parameter. ω is a frequency component parameter. f (x, y) is an initial phase parameter determined based on the position of the pixel in the divided block. Among these parameters, parameters that are largely related to the strength of the filter processing are the amplitude component parameter A and the frequency component parameter ω. When the amplitude component parameter A is large, the pixel replacement distance ΔY increases and the fluctuation increases. Also, if the frequency component parameter ω is small, the pixel replacement period 2π / ω is shortened, so that the fluctuation speed is increased and the fluctuation per unit time is increased.

  In the present embodiment, as shown in FIG. 11, the gazing point VP of the virtual camera VC is set for the moving object OB that moves in the object space, and when the moving object OB moves, the virtual camera VC The point of interest VP also moves in the object space. The visual line direction of the virtual camera VC is controlled so as to face the gazing point VP. For this reason, when the moving object OB moves and the position of the gazing point VP (three-dimensional coordinates in the world coordinate system) is changed, the scene seen from the virtual camera VC is different.

  By the way, since the filtering process for the original image employed in the present embodiment is a two-dimensional pixel processing process, it is irrelevant to changes in the viewpoint position, line-of-sight direction, angle of view, etc. of the virtual camera. For this reason, if the filtering process is such that its effect varies depending on the time parameter, the variation in image information due to the movement of the virtual camera and the variation in image information due to the effect of the filtering process cause interference, and some sort of The inconvenience of seeing something like the alias of can occur.

  Therefore, in the present embodiment, the filter strength parameter that determines the strength of the filtering process, that is, the degree of influence of the filtering process on the original image, is changed according to the moving distance L of the gazing point VP of the virtual camera VC. The effect is controlled so as to weaken.

  For example, when performing fluctuation filter processing involving pixel replacement processing on the original image, by reducing the amplitude component parameter A of the periodic function shown in FIG. 10, the pixel replacement distance ΔY can be kept short and fluctuation can be reduced. can do. Further, since the change in fluctuation per unit time is reduced by increasing the frequency component parameter ω, the effect of the filter processing can be weakened. Needless to say, it is effective to reduce the amplitude component parameter A and increase the frequency component parameter ω.

  Also, changing the filter strength parameter in this way means changing the appearance of the generated image. For this reason, if the filter strength parameter is frequently changed, there is a risk that the image may be difficult to see. Therefore, in the present embodiment, as shown in FIG. 12, when it is determined that the moving distance L of the gazing point VP of the virtual camera VC exceeds a given threshold value Lth, the amplitude component parameter A is set to the first value. The setting is changed from the amplitude level A1 to the second amplitude level A2 lower than the first amplitude level A1. If the movement distance L of the gazing point VP once exceeds the threshold value Lth and then changes below the threshold value Lth, the amplitude parameter A is changed from the second amplitude level A2 to the first amplitude level A1. To return. The change from the first amplitude level A1 to the second amplitude level A2 and the change from the second amplitude level A2 to the first amplitude level A1 are continuously brought close to the target level. This prevents a sudden change in the appearance of the image. The time t2 until the amplitude parameter A is returned from the second amplitude level A2 to the first amplitude level A1 is shorter than the time t1 until the amplitude parameter A is changed from the first amplitude level A1 to the second amplitude level A2. ing. This is because when the fluctuation filter process is constantly performed on the original image, it is preferable to quickly return to the original state.

  As described above, according to the filter strength parameter setting method of the present embodiment, it is possible to appropriately adjust the degree of influence of the filter processing on the original image. For this reason, according to this method, it is possible to prevent the image after filtering from being unnatural and poor in appearance, and it is possible to create a high-quality video. In particular, the method of the present embodiment is suitable when the effect of the filter process changes with time.

3. Processing of this embodiment Next, a detailed processing example of this embodiment will be described with reference to the flowcharts of FIGS.

  First, a description will be given using the flowchart of FIG.

  First, a moving object is drawn (S10). Subsequently, the presence / absence of a reflection line-of-sight vector to be calculated is confirmed (step S11). That is, when the virtual reflection surface object has an intersection with the visual vector of the virtual camera, it is determined that there is a reflective visual vector to be calculated. This processing is performed for all primitive surfaces constituting the virtual reflection surface object, and the reflection line-of-sight vector calculation processing can be omitted for primitive surfaces that do not have an intersection with the line-of-sight vector.

  Next, if it is determined that there is a reflected line-of-sight vector to be calculated (YES in step S11), an intersection determination between the reflected line-of-sight vector and the bounding sphere containing the moving object is performed (step S12). That is, as described with reference to FIGS. 3A to 3C, the distance between the extended line segment of the reflection line vector and the center of the bounding sphere is compared with the radius of the bounding sphere, and the reflection line of sight is compared. Determine whether the vector has an intersection with the bounding sphere. If it is determined that the reflection line-of-sight vector and the bounding sphere intersect (YES in step S13), a mirror image object obtained by flipping the moving object using the surface obtained by extending the surface of the virtual reflection surface object as a reference surface is arranged. Set and draw (step S14).

  Thereafter, a semi-transparent object is drawn to generate an original image (step S15), and a filtering process is performed on the generated original image (step S16).

  Next, the case where the fluctuation filter process is performed as the filter process of step S16 of FIG. 13 will be described using the flowchart of FIG.

  First, an original image is generated by drawing a scene viewed from the virtual camera in a frame buffer so that the α value of a region where ripples occur is α1 (for example, 128) or more and the α value of a region where ripples do not occur is less than α1. (Step S20).

  Next, on the basis of change information such as the position, direction, and angle of view of the virtual camera, whether the wave should be strengthened (whether the wavefront motion will increase) or the wave should be weakened (whether the wavefront motion will be small) Determine (step S21). For example, if the moving distance of the gazing point of the virtual camera exceeds a threshold value, it is determined that the wave should be weakened. In addition, for example, when the moving distance of the point of sight of the virtual camera changes from a state where it exceeds the threshold value to fall below the threshold value, it is determined that the wave should be strengthened.

  Next, a filter strength parameter setting process is performed. Specifically, the wave strength level (first level) when the wavefront motion is large and the wave strength level (second level) when the wavefront motion is small and ripples are set in advance. If the current wave intensity level is determined to be different from the target wave intensity level by comparing the current wave intensity level with the target value, Is performed so that the intensity value (amplitude component parameter or frequency component parameter of the periodic function) approaches the target value (first level or second level) (step S22).

  Next, table data (shift table) for shifting the position coordinates of each point of the pixel is created based on the wave intensity level set in step S22 (step S23). This table data is handled as an index texture in the index color / texture mapping.

  Next, a work buffer (reduction buffer) having a size half that of the frame buffer (display screen) is prepared, and the entire screen (original image) is reduced and copied to the work buffer (step S24).

  Next, the screen (work image) reduced and copied to the work buffer is divided into blocks each having a size of 16 × 16 (pixels), and each divided block is divided into 256 colors indexed by relative positions in the block. It is regarded as a lookup table (CLUT) and is set as a color lookup table for index color / texture mapping (step S25).

  Next, the table data for shifting the pixel position coordinates is regarded as an index texture of 256 colors, and the index texture is mapped to the position corresponding to each divided block while referring to the color lookup table set in step S15. A polygon (virtual object) is drawn (step S26). As a result, a filter image is created in the work buffer.

  Next, the work buffer for storing the image (filter image) subjected to the pixel replacement process is enlarged to the size of the frame buffer and written to the frame buffer (step S27). At this time, the α test is used to determine the state of the most significant bit of the α value bit string, and the pixels of the image obtained by enlarging the image stored in the work buffer only to pixels having an α value of α1 (for example, 128) or more are half. Combine with the original image of the frame buffer by transparent drawing.

  Next, the case where the glare filter process is performed as the filter process of step S16 of FIG. 13 will be described using the flowchart of FIG.

  First, an original image is generated by drawing a scene viewed from the virtual camera in a frame buffer so that the α value of a region where glare occurs is α1 (for example, 128) or more and the α value of a region where glare does not occur is less than α1. (Step S30).

  Next, the work buffer (first work buffer) WB1 having a size half that of the frame buffer is cleared. That is, the work buffer WB1 is painted black (R, G, B) = (0, 0, 0) (step S31).

  Next, the original image of the frame buffer is reduced and copied to the work buffer WB1 (step S32). At that time, the state of the most significant bit of the α value bit string is determined using an α test, and partial reduced copy is performed to reduce and copy to the work buffer only for pixels having an α value of α1 (eg, 128) or more. Then, the monochrome polygon image is subtracted and synthesized in the work buffer WB1 (step S33). That is, a component having a low color intensity is dropped by the color extraction processing described with reference to FIG.

  Next, the image of the work buffer WB1 is reduced and copied to a work buffer (second work buffer) WB2 having a size of 1/4 of the frame buffer (step S34). Then, using the method described in D1 and D2 of FIG. 9, an image obtained by shifting the image of the work buffer WB2 to the horizontal is added to the work buffer WB2, and the image is blurred in the horizontal direction (X direction). (Step S35). Further, using the method described in D1 and D3 of FIG. 9, an image obtained by shifting the image in the work buffer WB2 vertically is added to the work buffer WB2, and the image is blurred in the vertical direction (Y direction). This is performed (step S36).

  Next, the image of the work buffer WB2 is reduced and copied to a work buffer (third work buffer) WB3 having a size of 1/8 of the frame buffer (step S37). Then, in the same manner as in step S35, an image obtained by shifting the image in the work buffer WB3 horizontally is added and synthesized to the work buffer WB3 to perform a process of blurring the image in the horizontal direction (X direction) (step S38). Further, an image obtained by shifting the image of the work buffer WB3 vertically is added and synthesized to the work buffer WB3 by the same method as in step S36, and a process of blurring the image in the vertical direction (Y direction) is performed (step S39).

  Next, the image of the work buffer WB2 is enlarged to the size of the frame buffer, and the enlarged image is multiplied by an appropriate coefficient (first α value) and added to the frame buffer and synthesized (step S40). Further, the image of the work buffer WB3 is enlarged to the size of the frame buffer, and the enlarged image is multiplied and combined with an appropriate coefficient (second α value) in the frame buffer (step S41).

4). Hardware Configuration FIG. 8 shows an example of a hardware configuration capable of realizing this embodiment. The main processor 900 operates based on a program stored in a DVD 982 (information storage medium, which may be a CD), a program downloaded via the communication interface 990, a program stored in the ROM 950, or the like. Perform processing, sound processing, etc. The coprocessor 902 assists the processing of the main processor 900, and executes matrix operation (vector operation) at high speed. For example, when a matrix calculation process is required for a physical simulation for moving or moving an object, a program operating on the main processor 900 instructs (requests) the process to the coprocessor 902.

  The geometry processor 904 performs geometry processing such as coordinate conversion, perspective conversion, light source calculation, and curved surface generation based on an instruction from a program operating on the main processor 900, and executes matrix calculation at high speed. The data decompression processor 906 performs decoding processing of the compressed image data and sound data and accelerates the decoding processing of the main processor 900. Thereby, a moving image compressed by the MPEG method or the like can be displayed on the opening screen or the game screen.

  The drawing processor 910 executes drawing (rendering) processing of an object composed of primitive surfaces such as polygons and curved surfaces. When drawing an object, the main processor 900 uses the DMA controller 970 to pass the drawing data (vertex data and other parameters) to the drawing processor 910 and, if necessary, the texture to the texture storage unit 924. Forward. Then, the drawing processor 910 draws the object in the frame buffer 922 while performing hidden surface removal using a Z buffer or the like based on the drawing data and texture. The drawing processor 910 also performs α blending (translucent processing), depth cueing, mip mapping, fog processing, bilinear filtering, trilinear filtering, anti-aliasing, shading processing, and the like. When an image for one frame is written in the frame buffer 922, the image is displayed on the display 912.

  The sound processor 930 includes a multi-channel ADPCM sound source and the like, generates game sounds such as BGM, sound effects, and sounds, and outputs them through the speaker 932. Data from the game controller 942 and the memory card 944 is input via the serial interface 940.

  The ROM 950 stores system programs and the like. In the case of an arcade game system, the ROM 950 functions as an information storage medium, and various programs are stored in the ROM 950. A hard disk may be used instead of the ROM 950. The RAM 960 is a work area for various processors. The DMA controller 970 controls DMA transfer between the processor and the memory. The DVD drive 980 (may be a CD drive) accesses a DVD 982 (may be a CD) in which programs, image data, sound data, and the like are stored. The communication interface 990 performs data transfer with the outside via a network (communication line, high-speed serial bus).

  The processing of each unit (each unit) in this embodiment may be realized entirely by hardware, or may be realized by a program stored in an information storage medium or a program distributed via a communication interface. Also good. Alternatively, it may be realized by both hardware and a program.

  When the processing of each part of this embodiment is realized by both hardware and a program, a program for causing the hardware (computer) to function as each part of this embodiment is stored in the information storage medium. More specifically, the program instructs the processors 902, 904, 906, 910, and 930, which are hardware, and passes data if necessary. Each processor 902, 904, 906, 910, 930 realizes the processing of each unit of the present invention based on the instruction and the passed data.

  The present invention is not limited to that described in the above embodiment, and various modifications can be made. For example, terms cited as broad or synonymous terms in the description in the specification or drawings can be replaced with broad or synonymous terms in other descriptions in the specification or drawings. Further, the arrangement setting method of the mirror image object, the glare filter method, the fluctuation filter method, and the like are not limited to those described in the present embodiment, and techniques equivalent to these are also included in the scope of the present invention.

  The present invention can also be applied to various games (such as fighting games, shooting games, robot fighting games, sports games, competitive games, role playing games, music playing games, dance games, etc.). Further, the present invention is applied to various image generation systems such as a business game system, a home game system, a large attraction system in which a large number of players participate, a simulator, a multimedia terminal, a system board for generating a game image, and a mobile phone. it can.

The functional block diagram of the image generation system of this embodiment. Explanatory drawing of the method of this embodiment. FIG. 3A to FIG. 3C are explanatory diagrams of the method of this embodiment. FIG. 4A to FIG. 4C are explanatory diagrams of the method of this embodiment. FIG. 5A to FIG. 5C are explanatory diagrams of the method of this embodiment. Explanatory drawing of the method of this embodiment. FIG. 7A to FIG. 7C are explanatory diagrams of the method of this embodiment. Explanatory drawing of the method of this embodiment. Explanatory drawing of the method of this embodiment. Explanatory drawing of the method of this embodiment. Explanatory drawing of the method of this embodiment. Explanatory drawing of the method of this embodiment. The flowchart which shows the specific process example of this embodiment. The flowchart which shows the specific process example of this embodiment. The flowchart which shows the specific process example of this embodiment. Hardware configuration example.

Explanation of symbols

POB moving object, WOB water surface object (translucent object),
MOB mirror image object, GOB terrain object,
VC virtual camera, Vc line-of-sight vector, Vr reflection line-of-sight vector,
Vlm bounding volume,
100 processing unit,
110 object space setting unit, 111 mirror image object setting unit,
112 movement / motion processing unit, 114 virtual camera control unit, 116 event determination unit,
118 parameter setting unit, 120 drawing unit, 130 sound generation unit,
160 operation unit, 170 storage unit,
171 main storage unit, 172 drawing buffer, 173 texture storage unit,
174 Z buffer, 175 LUT storage unit, 176 Object data storage unit,
180 information storage medium, 190 display unit, 192 sound output unit,
194 Portable information storage device, 196 communication unit

Claims (11)

A program for generating an image viewed from a virtual camera in an object space,
An event determination unit that determines whether or not a reflection event has occurred in which the moving object is reflected in the translucent object to be filtered;
A mirror image object setting unit configured to place and set a mirror image object of the moving object at a position where the moving object is flipped with respect to a given reference plane when it is determined that the reflection event has occurred;
As a drawing unit that performs filter processing on the original image on which the translucent object is drawn after drawing the moving object and the mirror image object,
A program characterized by causing a computer to function. In claim 1,
A virtual reflecting surface object corresponding to the translucent object is arranged and set in the object space,
The event determination unit
A determination is made as to whether or not the reflection event has occurred by performing an intersection determination between a reflection line-of-sight vector obtained by reflecting the line-of-sight vector of the virtual camera with the virtual reflecting surface object and the moving object. program. In claim 1,
A virtual reflecting surface object corresponding to the translucent object is arranged and set in the object space,
The event determination unit
A bounding volume that includes the moving object is set, and the reflection event vector obtained by reflecting the visual vector of the virtual camera by the virtual reflecting surface object and the bounding volume are determined to generate the reflection event. A program characterized by determining whether or not it has been performed. In claim 2 or 3,
The virtual reflecting surface object is divided into a plurality of primitive surfaces;
The event determination unit
A program characterized by omitting the calculation processing of the reflection line-of-sight vector for a primitive surface that does not intersect with the line-of-sight vector. In any one of Claims 1-4,
The drawing unit
Filtering the image using the α value set in the α plane of the original image in which the translucent object is drawn with an α value different from the object group including the moving object and the mirror image object as mask information A program characterized by being performed. In claim 5,
The drawing unit
Generate a work image obtained by copying only the drawing area of the translucent object in the original image using the α value set in the α plane of the original image as mask information, and generate a filter image based on the work image. A program for performing the filter processing for synthesizing the original image and the filter image. In claim 5,
The drawing unit
A filter image is generated based on a work image obtained by copying the original image, and only the drawing area of the semi-transparent object in the filter image is used as the mask information with the α value set in the α plane of the original image as mask information. A program characterized by performing processing to synthesize. In any one of Claims 1-7,
A virtual camera control unit that controls the virtual camera based on given control information;
Based on the control information of the virtual camera, when it is determined that at least one of the position, direction, and angle of view of the virtual camera has changed, a computer is used as a parameter setting unit that changes the filter strength parameter of the filtering process. A program characterized by functioning. In claim 8,
A gazing point of the virtual camera is set for the moving object,
The parameter setting unit
When the moving object moves in the object space and the gazing point of the virtual camera moves, the filter strength parameter is changed according to the moving distance.   An information storage medium readable by a computer, wherein the program according to any one of claims 1 to 9 is stored. An image generation system for generating an image viewed from a virtual camera in an object space,
An event determination unit that determines whether or not a reflection event has occurred in which the moving object is reflected in the translucent object to be filtered;
A mirror image object setting unit configured to place and set a mirror image object of the moving object at a position where the moving object is flipped with respect to a given reference plane when it is determined that the reflection event has occurred;
A drawing unit for drawing the moving object, the mirror image object, and the translucent object;
Including
The drawing unit
An image generation system characterized by performing a filtering process on an original image on which the translucent object is drawn after drawing the moving object and the mirror image object.

Images