JP2007026325A - Program, information storage medium, and image generation system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image generation system, a program and the like capable of generating an image less in the feeling of afterimage. <P>SOLUTION: The image generation system includes: a plotting part for plotting an object and generating image data; and an over-drive effect processing part for performing over-drive effect processing in the generated image data and generating the image data to be outputted to a display part. The over-drive effect processing part generates the image data where the over-drive effect processing is performed by conducting the α-blending processing of IMK+(IMK-IMJ)×α, based on the image data IMK which is generated by a K-th frame, the image data IMJ which is generated by plotting the object in the J-th frame (K>J), and an α-value α. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

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

  In recent years, portable game devices equipped with high-quality liquid crystal display devices have gained popularity. In this portable game device, the number of pixels of the liquid crystal display device is large, and a real high-definition image can be displayed. Can enjoy.

  By the way, in the liquid crystal display device, since the response speed of the liquid crystal is slow, when a moving image is displayed, a phenomenon such as an afterimage or a moving image appears blurred. As a conventional technique for improving such a phenomenon, a liquid crystal display device including an overdrive circuit has been proposed. In this overdrive circuit, the response characteristic to the step input of the liquid crystal is improved by applying a voltage higher than the target voltage in the first frame of the input change.

However, in this prior art, the response speed of the liquid crystal is improved by performing compensation processing on the voltage of the image signal. Therefore, if the portable game device does not include an overdrive circuit that performs compensation processing at such a voltage level, there is a problem that it is difficult to improve the afterimage feeling.
Japanese Patent Laid-Open No. 7-20828

  The present invention has been made in view of the above problems, and an object of the present invention is to provide an image generation system, a program, and an information storage medium capable of generating an image with little afterimage.

  The present invention is an image generation system for generating an image, for drawing an object to generate image data, performing overdrive effect processing on the generated image data, and outputting the result to a display unit An overdrive effect processing unit that generates image data of the image data, and the overdrive effect processing unit draws an object in the image data IMK generated in the Kth frame and the Jth (K> J) frame. Image generation for generating image data subjected to overdrive effect processing by performing α blending processing of IMK + (IMK−IMJ) × α based on image data IMJ generated in this way and α value α Related to the system. 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 a computer-readable information storage medium that stores (records) a program that causes a computer to function as each unit.

  In the present invention, image data is generated by drawing an object. Then, overdrive effect processing is performed on the generated image data, and image data to be output to the display unit (display device) is generated. Specifically, an overdrive effect process that realizes overdrive is performed as an effect process (post-effect process, filter process) for image data (original image data) generated by drawing an object. The subsequent image data is output to the display unit. In this way, even when the display unit does not include a hardware overdrive circuit, the same effect as overdrive can be realized by overdrive effect processing, and an image with less afterimage can be generated. .

  In the present invention, the α blending process of IMK + (IMK−IMJ) × α is performed based on the image data IMK, IMJ, and α generated in the Kth and Jth frames, thereby performing the overdrive effect processing. Image data is generated. In this way, the image data after the overdrive effect process can be generated only by performing the α blending process on the image data generated by drawing the object. Therefore, an image with little afterimage feeling can be generated with a small processing load.

  In the image generation system, the program, and the information storage medium according to the present invention, the overdrive effect processing unit maps the texture of the image data IMK onto a primitive surface having a screen size or a divided screen size in which an α value is set. The primitive surface to which the texture is mapped may be α blended with respect to the buffer in which the image data IMJ is drawn.

  In this way, for example, overdrive effect processing can be realized by one texture mapping, and the processing load can be reduced. In addition, it is possible to realize overdrive effect processing by effectively utilizing the texture mapping function of the image generation system or the like.

  In the image generation system, the program, and the information storage medium according to the present invention, the overdrive effect processing unit may perform AS = (1 + α) in the double value mode in which a value twice the set value AS is set as the source α value A. ) / 2, BS = α is set in the fixed value mode in which the set value BS is set as the fixed destination α value B, and IMK × A−IMJ × B = IMK × (2 × AS) −IMJ Subtraction α blending drawing of × BS = IMK × (1 + α) −IMJ × α may be performed.

  In this way, even if the equation of IMK + (IMK−IMJ) × α is not prepared as an α blending equation, overdrive effect processing can be realized using a general subtraction α blending equation. Become.

  In the image generation system, the program, and the information storage medium according to the present invention, the overdrive effect processing unit generates the image data IMK by drawing the object in the first buffer in the Kth frame. Based on the image data IMK, the image data IMJ in the Jth frame written in the second buffer, and the α value α, α blending processing of IMK + (IMK−IMJ) × α is performed, and overdrive is performed. The image data on which the effect processing has been performed is written in the second buffer, and in the Lth frame, the object is drawn in the third buffer to generate the image data IML. The generated image data IML and the first data IML + (IML) on the basis of the image data IMK in the Kth frame written in the buffer and the α value α. IMK) × α α blending processing is performed, and the image data subjected to the overdrive effect processing is written into the first buffer. In the Mth (M> L> K) frame, the object is stored in the second buffer. Drawing is performed to generate image data IMM. Based on the generated image data IMM, the image data IML in the Lth frame written in the third buffer, and the α value α, IMM + (IMM− (IML) × α blending processing may be performed, and the image data subjected to the overdrive effect processing may be written to the third buffer.

  In the present invention, the roles of the first, second, and third buffers are sequentially switched for each frame. In this way, useless copy processing of image data between buffers becomes unnecessary, and the number of processing times is reduced, so that the processing load can be reduced.

  In the image generation system, the program, and the information storage medium according to the present invention, the overdrive effect processing unit performs the overdrive effect processing only on the image data in a specific area of the display area of the display unit. You may do it.

  In this way, since it is not necessary to perform overdrive effect processing for the entire display area, the processing load can be reduced.

  In the image generation system, the program, and the information storage medium according to the present invention, the drawing unit generates image data by drawing a plurality of objects, and the overdrive effect processing unit specifies the plurality of objects. The overdrive effect process may be performed on a region containing the object.

  In this way, it is possible to reduce the afterimage feeling of an image of a specific object by performing overdrive effect processing on the specific object.

  In the image generation system, the program, and the information storage medium according to the present invention, the overdrive effect processing unit is based on the vertex coordinates of the object, or the vertex coordinates of the simple object when a simple object is set for the object. Thus, the area for performing the overdrive effect process may be set.

  In this way, the area setting process can be simplified.

  The image generation system, program, and information storage medium according to the present invention include a display control unit that performs display control of an adjustment screen for adjusting the α value of the overdrive effect processing (or functions as a display control unit). The overdrive effect processing unit may perform the overdrive effect processing based on the adjusted α value when the α value is adjusted on the adjustment screen.

  In this way, overdrive effect processing corresponding to various types of display units can be realized.

  In the image generation system, the program, and the information storage medium according to the present invention, the display control unit moves the object set to the second intermediate color on the background area of the adjustment screen set to the first intermediate color. Display control may be performed.

  For example, if the background area or the color of the object is the primary color, it is difficult to see an afterimage generated by the movement of the object, and it is difficult to adjust the effect intensity of the overdrive effect process. On the other hand, if the background region and the object set to different intermediate colors are used as in the present invention, the afterimage feeling of the object can be enhanced on the adjustment screen, and the adjustment accuracy of the adjustment screen can be improved.

  The image generation system, program, and information storage medium according to the present invention include a display control unit that performs display control of a mode setting screen for setting whether to enable the overdrive effect processing (or display control). The overdrive effect processing unit may perform the overdrive effect processing when the setting for enabling the overdrive effect processing is performed on the mode setting screen. .

  In this way, for example, when a display unit that does not require overdrive effect processing is used, a situation in which unnecessary overdrive effect processing is performed can be prevented.

  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 device, portable game device) 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, and the function can be realized by a lever, a button, a steering, a microphone, a touch panel display, or a housing. The storage unit 170 serves as a work area or main memory such as the processing unit 100 or the communication unit 196, and its function can be realized by a RAM (VRAM) or the like.

  An information storage medium 180 (a computer-readable medium) stores programs, data, and the like, and its function can be realized by an optical disk (CD, DVD), hard disk, memory (ROM), or the like. 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 the processing procedure 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 (Liquid Crystal Display), touch panel display, HMD (Head Mount 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 the present 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 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 display control 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 includes various objects (primitive surfaces such as polygons, free-form surfaces, and subdivision surfaces) representing display objects such as characters, cars, tanks, buildings, trees, columns, walls, and maps (terrain). (Object) is set in the object space. That is, the position and rotation angle (synonymous with direction and direction) of the object (model object) in the world coordinate system are determined, and the rotation angle (X, Y, Z axis around the position (X, Y, Z)) is determined. Arrange objects at (rotation angle).

  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, an object (moving object) is moved in the object space or an object is moved 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. Perform processing (motion, animation). Specifically, simulation processing for sequentially obtaining object movement information (position, rotation angle, speed, or acceleration) and motion information (position or rotation angle of each part object) every frame (1/60 seconds) I do. The frame (frame rate) is a unit of time for performing object movement / motion processing (simulation processing) and image generation processing.

  The virtual camera control unit 114 (viewpoint control unit) performs control processing of the virtual camera (viewpoint) for generating an image that can be seen from a given (arbitrary) viewpoint in the object space. Specifically, a process for controlling the position (X, Y, Z) or the rotation angle (rotation angle about the X, Y, Z axes) of the virtual camera (process for controlling the viewpoint position and the line-of-sight direction) is performed.

  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.

  The display control unit 116 performs display control of various screens such as an adjustment screen and a mode setting screen. Specifically, the display control unit 116 performs display control of an adjustment screen for adjusting the α value (effect intensity) of the overdrive effect process. Specifically, the object set to the second intermediate color different from the first intermediate color on the background area (adjustment screen area, adjustment window) set to the first intermediate color (non-primary color) is displayed. Display control to move. The display control unit 116 also performs display control of a mode setting screen for setting whether to enable overdrive effect processing. When the setting for enabling the overdrive effect processing is performed on the mode setting screen, the overdrive effect processing is performed. The same screen may be shared as the adjustment screen and the mode setting screen.

  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 ( The position coordinates, texture coordinates, color data, normal vector, α value, etc.) of the vertexes of the primitive surface are created. Based on the drawing data (primitive surface data), the object (one or a plurality of primitive surfaces) after the perspective transformation (after the geometry processing) is selected from the first, second, and third buffers 171, 172, and 173. Draw in the buffer set in the drawing buffer. As a result, an image that can be seen from the virtual camera (given viewpoint) in the object space is generated. Then, the generated image is output to the display unit 190 via the buffer set as the display buffer among the first, second, and third buffers 171, 172, and 173.

  The first, second, and third buffers 171, 172, and 173 are buffers (image buffers) that can store image information in units of pixels, such as frame buffers and work buffers, and are secured on, for example, the VRAM of the image generation system. Is done. In the present embodiment, the first, second, and third buffers 171, 172, and 173 are configured as a triple buffer. However, the drawing buffer (back buffer) and the display buffer (front buffer) are configured as a double buffer. Good. In this case, the buffer that was the drawing buffer in the Jth frame is set as the display buffer in the Kth (K> J) frame, and the buffer that was the display buffer in the Jth frame is set in the Kth frame. A frame may be set in a drawing buffer. Alternatively, four or more buffers may be used.

  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.

  The drawing unit 120 can perform texture mapping processing, hidden surface removal processing, and α blending processing.

  Here, the texture mapping process is a process of mapping a texture (texel value) stored in the texture storage unit 174 to an object. Specifically, the texture (surface properties such as color and α value) is read from the texture storage unit 174 using the texture coordinates set (given) at the vertices of the object (primitive surface). Then, a texture that is a two-dimensional image or pattern is mapped to the object. In this case, processing for associating pixels and texels, bilinear interpolation (texel interpolation), and the like are performed.

  The hidden surface removal processing is realized by, for example, a Z buffer method (depth comparison method, Z test) using a Z buffer 176 (depth buffer) in which the Z value (depth information) of each pixel is stored. That is, when drawing each pixel on the primitive surface of the object, the Z value stored in the Z buffer 176 is referred to. Then, the Z value of the referenced Z buffer 176 is compared with the Z value at the drawing target pixel of the primitive surface, and the Z value of the primitive surface is the front side when viewed from the virtual camera (for example, a large Z value). ), The pixel drawing process is performed and the Z value of the Z buffer 176 is updated to a new Z value.

  The α blending process is a process performed based on the α value (A value), and includes normal α blending, addition α blending, subtraction α blending, and the like. 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 translucency (equivalent to transparency and opacity) information, mask information, or bump information.

  The drawing unit 120 includes an overdrive effect processing unit 122. The overdrive effect processing unit 122 performs overdrive effect processing by software. Specifically, when the drawing unit 120 draws the object in one of the first, second, and third buffers 171, 172, and 173 to generate image data (original image data), the overdrive is performed. The effect processing unit 122 performs overdrive effect processing on the generated image data (digital data), and generates image data to be output to the display unit 190. That is, the image data (digital data) that has been subjected to the overdrive effect process is written into the buffer set as the display buffer among the first, second, and third buffers 171, 172, and 173.

  More specifically, the overdrive effect processing unit 122 uses the image data IMK generated in the Kth frame (current frame) and the Jth (K> J) frame (previous frame, past frame). Based on the image data IMJ generated by drawing the object and the α value α, the α blending process of IMK + (IMK−IMJ) × α is performed to obtain the image data subjected to the overdrive effect process. Generate. For example, the overdrive effect processing unit 122 maps the texture of the image data IMK onto a primitive surface (sprite, polygon) having a screen size or a divided screen size for which an α value is set. The primitive surface to which the texture is mapped is subjected to α blending drawing with respect to a buffer (display buffer) in which the image data IMJ is drawn. In this case, AS = (1 + α) / 2 is set in the double value mode in which a value twice the set value AS is set as the source α value A. Also, BS = α is set in a fixed value mode in which the set value BS is set as a fixed destination α value B. Then, IMK * A-IMJ * B = IMK * (2 * AS) -IMJ * BS = IMK * (1+ [alpha])-IMJ * [alpha] blending is performed to generate image data subjected to overdrive effect processing To do.

  The overdrive effect processing unit 122 draws the object in the first buffer 171 to generate image data IMK in the Kth frame. Then, based on the generated image data IMK, the image data IMJ in the Jth frame written in the second buffer 172, and the α value α, α blending processing of IMK + (IMK−IMJ) × α And write to the second buffer 172. In the Lth frame, the object is drawn in the third buffer 173 to generate image data IML. Based on the generated image data IML, the image data IMK in the Kth frame written in the first buffer 171 and the α value α, α blending processing of IML + (IML−IMK) × α is performed. And write to the first buffer 171. In the Mth frame, the object is drawn in the second buffer 172 to generate image data IMM. Then, based on the generated image data IMM, the image data IML in the Lth frame written in the third buffer 173, and the α value α, α blending processing of IMM + (IMM−IML) × α And write to the third buffer 173.

  Note that the original image data generated in the buffer set as the drawing buffer among the first, second, and third buffers 171, 172, and 173 is, for example, a hidden surface using a Z buffer 176 that stores Z values. It is generated by drawing an object (primitive surface) while erasing.

  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).

2. 2. Method of this Embodiment 2.1 Principle of Overdrive Effect Processing The principle of overdrive effect processing according to this embodiment will be described. 2A and 2B, when attention is paid to a certain pixel, the image data (digital image data value) in the previous J-th frame is IMJ, and the image data in the current K-th frame is Suppose that it was IMK. In this case, if the response speed of the display unit 190 is sufficiently high, the correct image data (color data) IMK is written in the display buffer (buffer set in the display buffer) in the Kth frame, whereby the display unit 190 is displayed. The brightness of the corresponding pixel in is the brightness to be set by IMK.

  However, when the display unit 190 is a liquid crystal display device or the like, the response speed of the liquid crystal is slow. Therefore, even if correct image data IMK is written, the luminance of the corresponding pixel in the display unit 190 should be set by the IMK. It may not be. For example, in the case of FIG. 2A, the brightness is darker than the brightness to be set by IMK, and in the case of FIG. 2B, the brightness is brighter than the brightness to be set by IMK. As a result, there arises a problem that a feeling of afterimage appears or the moving image looks blurred.

  In this case, if the display unit 190 includes a hardware overdrive circuit, such a problem of afterimage can be prevented. However, many liquid crystal display devices of portable game devices do not include such an overdrive circuit. In a home game machine, various types of display units (display devices) may be connected to the game machine body. For example, a cathode ray tube television or a liquid crystal television is connected. In addition, a liquid crystal television with a built-in overdrive circuit is connected, or a liquid crystal television without a built-in circuit is connected.

  If the display unit 190 does not include a hardware overdrive circuit, the afterimage is noticeable and the quality of the generated game image deteriorates. In particular, in a game image in which a plurality of objects (display objects) move on the screen at high speed, the outline of the object is blurred, which may hinder the game play of the player.

  Therefore, in this embodiment, such a problem is solved by performing overdrive effect processing by software. That is, normally, image data (original image data) generated by drawing an object is output to the display unit 190 as it is. On the other hand, in this embodiment, overdrive effect processing by software as post-filter processing is performed on image data generated by drawing an object. Specifically, in FIG. 2A, since the difference image data IMK-IMJ is a positive value, the image data IMODK after the overdrive effect processing is set to a value larger than IMK, and the overdrive in the positive direction is performed. Perform effect processing. In FIG. 2B, since the difference image data IMK-IMJ has a negative value, the image data IMODK after the overdrive effect processing is set to a value smaller than IMK, and the overdrive effect processing in the negative direction is performed. . Then, the image data after the overdrive effect processing is written into the display buffer and output to the display unit 190.

  In this way, even if the display unit 190 does not include a hardware overdrive circuit, the response speed of the liquid crystal or the like can be improved and the afterimage can be reduced.

  Note that there is a blurring process (blurring process) used for flicker free or the like as a process different from the overdrive effect process of the present embodiment. In this blurring process, as shown in FIG. 2C, image data IMJ and IMK in the Jth and Kth frames are blended to generate intermediate image data IMBK between IMJ and IMK.

  On the other hand, in the overdrive effect process, as shown in FIG. 2C, image data of IMODK = IMK + (IMK−IMJ) × K1 exceeding the IMK is generated. That is, the difference image data IMK-IMJ between the image data IMK of the current frame and the image data IMJ of the previous frame is obtained, and the difference image data IMK-IMJ multiplied by the effect intensity coefficient K1 (α value) A process of adding to the frame image data IMK is performed to generate IMODK. In this way, since IMODK exceeding IMK is set as the target value, the luminance of the corresponding pixel in the display unit 190 can be set to luminance according to IMK even when the reaction speed of the liquid crystal is slow. Become.

2.2 Details of Overdrive Effect Processing Next, details of the overdrive effect processing of the present embodiment will be described with reference to operation flowcharts of FIGS. For example, it is assumed that the object OB has moved as shown in FIGS. 5 (A), 5 (B), and 6 (A). 5A, 6B, and 6A are respectively a first frame (Jth frame in a broad sense), a second frame (Kth frame in a broad sense), and a third frame. It is an image in a frame (Lth frame in a broad sense).

  Here, when the maximum value of the image data (color data, luminance) is “100” and the minimum value is “0”, the value of the image data of the object OB is “70”, which is an intermediate color, and the background. The value of the image data in the area is “50” which is an intermediate color. When the object OB is moved at a high speed and displayed on the display unit 190 of the liquid crystal display device, an afterimage as shown in FIG. 6B is generated. That is, when the object OB moves, the luminance of the portion indicated by A1 in FIG. 6B should be the luminance corresponding to “50” that is the image data of the background area, but the response speed of the liquid crystal is slow. The luminance is larger than the luminance corresponding to “50”. As a result, an afterimage is generated in the portion indicated by A1. The same applies to the portion indicated by A2.

  In order to prevent the occurrence of such an afterimage, in this embodiment, the overdrive effect process shown in FIG. 3 is performed.

  For example, in the second frame, from the image data IM2 of the second frame (Kth frame) that is the current frame, the image data IM1 of the first frame (Jth frame) that is the previous (past) frame. Difference processing for subtracting is performed (step S1). In this way, for example, when the object OB moves as shown in FIGS. 5A and 5B, difference image data (difference mask, difference plane) IM2-IM1 as shown in FIG. 7A is generated. The

  That is, in the portion indicated by B1 in FIG. 7A, since the image data has changed from IM1 = 70 to IM2 = 50, the difference image data is IM2-IM1 = 50-70 = -20. In the portion indicated by B2, since the image data has not changed such as IM1 = 70 and IM2 = 70, IM2−IM1 = 0. In the portion indicated by B3, since the image data has changed from IM1 = 50 to IM2 = 70, IM2-IM1 = 70-50 = 20.

  Next, a process of multiplying the difference image data IM2-IM1 by an overdrive effect intensity coefficient K1 (α value) is performed to generate (IM2-IM1) × K1 (step S2).

  For example, in FIG. 7B, the effect intensity coefficient is K1 = 0.5, and this effect intensity coefficient K1 is multiplied by the difference image data in FIG. 7A, so that the portions indicated by C1, C2, and C3 are shown. The image data is “−10”, “0”, and “10”, respectively.

  Next, a process of adding (IM2−IM1) × K1 to the image data IM2 of the second frame that is the current frame is performed to generate IM2 + (IM2−IM1) × K1 (step S3). Then, the generated image data IMOD2 = IM2 + (IM2-IM1) × K1 after the overdrive effect processing is output to the display unit 190.

  For example, in the portion indicated by D1 in FIG. 8A, the image data (IM2-IM1) × K1 = −10 of the portion indicated by C1 in FIG. 7B is added to the image data IM2 = 50 in the background region. Therefore, the image data after the overdrive effect processing is IMOD2 = 40. Further, in the portion indicated by D2 in FIG. 8A, the image data (IM2-IM1) × K1 = 0 of the portion indicated by C2 in FIG. 7B is added to the image data IM2 = 70 of the object OB. Therefore, the image data after the overdrive effect processing is IMOD2 = 70. Further, in the portion indicated by D3 in FIG. 8A, the image data (IM2-IM1) × K1 = 10 of the portion indicated by C3 in FIG. 7B is added to the image data IM2 = 70 of the object OB. Therefore, the image data after the overdrive effect processing is IMOD2 = 80. By outputting the image data after the overdrive effect processing as shown in FIG. 8A to the display unit 190, the afterimage feeling can be reduced.

  For example, in the part indicated by A1 in FIG. 6B, the image data output to the display unit 190 is “50”, which is the image data of the background area, but the afterimage is generated because the response speed of the liquid crystal is slow. It has occurred. On the other hand, in the present embodiment, image data “40” smaller than the image data “50” of the background area is output to the display unit 190 in the portion indicated by D1 in FIG. Accordingly, in the portion D1, the overdrive effect processing in the negative direction shown in FIG. 2B is performed, and the occurrence of an afterimage as shown in A1 in FIG. 6B can be reduced.

  In the next third frame, a difference process is performed to subtract the image data IM2 of the second frame (Kth frame) from the image data IM3 of the third frame (Lth frame) (step S4). Then, a process of multiplying the obtained difference image data IM3-IM2 by an overdrive effect intensity coefficient K1 is performed (step S5).

  Next, a process of adding the generated (IM3-IM2) × K1 to the image data IM3 of the third frame is performed (step S6). Then, the generated image data IMOD3 = IM3 + (IM3−IM2) × K1 after the overdrive effect processing is output to the display unit 190.

  By the way, when the response speed of the liquid crystal is extremely slow, the overdrive effect processing based on the difference image data for one frame may be insufficient for reducing the afterimage.

  Therefore, in the operation flow of FIG. 4, the image data for difference reduction processing obtained based on the difference image data in the past frame is saved, and the difference image data in the current frame and the saved difference reduction data are saved. Overdrive effect processing is performed based on the image data for processing.

  For example, as shown in FIG. 4, in the second frame, difference processing (step S11) and multiplication processing (step S12) are performed to generate (IM2-IM1) × K1. Then, this (IM2−IM1) × K1 is multiplied by the effect intensity coefficient for difference reduction processing to generate image data (IM2−IM1) × K2 for difference reduction processing (step S13). Here, K1> K2. Then, the generated image data (IM2-IM1) × K2 for difference easing processing is stored.

  For example, in FIG. 8B, the image data “−10”, “0”, and “10” shown in C1, C2, and C3 in FIG. 7B are multiplied by the effect intensity coefficient for difference reduction processing. Thus, image data “−2”, “0”, and “2” for difference smoothing processing as indicated by E1, E2, and E3 are generated. It should be noted that image data for difference easing processing may be generated from the difference image data in FIG.

  In the next third frame, difference processing is performed to generate difference image data as shown in FIG. 9A (step S15). Then, the overdrive effect intensity coefficient is multiplied to generate image data (IM3-IM2) × K1 as shown in FIG. 9B (step S16).

  Next, a process of adding (or subtracting) the stored image data (IM2-IM1) × K2 for difference reduction processing to the generated image data (IM3-IM2) × K1, IM3-IM2) * K1 + (IM2-IM1) * K2 is generated (step S17). That is, the image data for difference smoothing processing in FIG. 8B is added (or subtracted) to the image data in FIG. 9B. As a result, image data (mask) as shown in FIG. 10A is generated. That is, 0-2 = -2 in the portion indicated by F1, -10 + 0 = -10 in the portion indicated by F2, and -10 + 2 = -8 in the portion indicated by F3. In the portion indicated by F4, 0 + 2 = 2, and in the portion indicated by F5, 10 + 0 = 10.

  Next, the generated (IM3−IM2) × K1 + (IM2−IM1) × K2 is added to the image data IM3 of the third frame (step S18). Then, the generated image data IMOD3 = IM3 + (IM3−IM2) × K1 + (IM2−IM1) × K2 after the overdrive effect processing is output to the display unit 190. That is, the image data IMOD3 after the overdrive effect processing as shown in FIG. Further, a process of multiplying (IM3−IM2) × K1 + (IM2−IM1) × K2 by an effect intensity coefficient for difference reduction processing is performed (step S19).

  If the difference reduction process as shown in FIG. 4 is performed, an overdrive effect process to which the effect of the past difference image data is applied can be realized. In other words, when the response speed of the liquid crystal is extremely slow, an afterimage may remain in a portion indicated by G1 in FIG. On the other hand, if the difference easing process is performed, an overdrive effect process at a portion indicated by G1 or the like can be realized. For example, in the portion indicated by G1, overdrive effect processing of “−2” is performed in the negative direction, and the occurrence of afterimages is reduced.

  In FIG. 4, (IM2−IM1) × K2 is stored as the image data for difference smoothing processing, but the present embodiment is not limited to this. In other words, the image data for difference softening processing to be stored may be image data obtained based on the difference image data IM2-IM1, for example, the difference image data IM2-IM1 itself is stored, or the difference image data is used for overdrive. (IM2−IM1) × K1 obtained by multiplying the effect intensity coefficients may be stored.

  Further, the overdrive effect processing of the present embodiment may be performed in units of image planes or in units of pixels. For example, FIG. 11 shows an example of overdrive effect processing in the case where the processing is performed in pixel units.

  First, a difference value between the image data in the current frame of the pixel to be processed and the image data in the previous frame is obtained (step S21). Then, it is determined whether or not the difference value is 0 (step S22). If the difference value is 0, the image data in the current frame is written in the corresponding pixel of the display buffer (step S23). On the other hand, if the difference value is not 0, overdrive effect processing is performed based on the difference value, and image data after the overdrive effect processing is obtained (step S24). Then, the image data after the overdrive effect processing is written into the corresponding pixel of the display buffer (step S25). Next, it is determined whether or not the processing has been completed for all the pixels (step S26). If not, the processing returns to step S21 and proceeds to the processing for the next pixel. On the other hand, if it is completed, the process is terminated.

  3 and 4, the effect intensity coefficient is described as being a constant value. However, the present embodiment is not limited to this, and the effect intensity coefficient may be a variable value. For example, overdrive effect processing may be performed based on an effect intensity coefficient (α value) that increases as the value (absolute value) of difference image data increases.

  Specifically, a table associating the difference image data value with the effect intensity coefficient (α value) as shown in FIG. 12 is prepared. Based on the obtained difference image data value, the effect intensity coefficient is referred to from the table of FIG. Then, in steps S2 and S5 in FIG. 3, steps S12 and S16 in FIG. 4, etc., the referenced effect intensity coefficient is multiplied by the difference image data. In this way, for example, as the difference image data value increases, the effect of the overdrive effect processing increases. Therefore, even when the response speed of the liquid crystal is slow, it is possible to minimize the occurrence of afterimages.

2.3 Method for Realizing Overdrive Effect Processing Next, a method for realizing overdrive effect processing according to the present embodiment will be described. In this implementation method, α blending processing is performed to realize overdrive effect processing. That is, the α value is used as the effect intensity coefficient. More specifically, based on the image data IMK generated in the Kth frame, the image data IMJ generated by drawing the object in the Jth (K> J) frame, and the α value α. , IMK + (IMK−IMJ) × α is blended.

  For example, in FIG. 13A, in the first frame (Jth frame), the image data IM1 in the first frame is generated by drawing an object. In the next second frame (Kth frame), the image data IM2 in the second frame is generated by drawing the object. Based on the image data IM2 and IM1 and the α value α, α blending processing is performed to generate image data IMOD2 = IM2 + (IM2−IM1) × α on which overdrive effect processing has been performed. Then, the generated image data IMOD2 is output to the display unit.

  According to this realization method, the image data subjected to the overdrive effect process can be generated only by performing the α blending process on the original image data. Therefore, there is an advantage that the processing load is light.

  That is, as shown in FIG. 14, the texture of the image data IM2 (IMK) is mapped to a primitive surface PL (sprite, polygon) having a screen size or a divided screen size in which an α value is set at a vertex or the like. Then, the image data IMOD2 on which the overdrive effect processing has been performed is performed by subjecting the primitive surface PL to which the texture is mapped to α blending to a buffer (for example, a display buffer) in which the image data IM1 (IMJ) is drawn. = IM2 + (IM2-IM1) × α is generated. In this way, for example, overdrive effect processing can be realized by one texture mapping, and the processing load can be reduced. In general, this type of image generation system has a texture mapping function. Therefore, according to the realization method of the present embodiment, there is an advantage that even if the display unit does not have a hardware overdrive circuit, overdrive effect processing can be realized by effectively using this texture mapping function.

  The α blending process is prepared for a translucent process and a blur process. That is, in FIG. 2C, it is prepared for obtaining image data IMBK intermediate between the image data IMK and IMJ. Therefore, in the blending circuit of the image generation system, there is a case where the formula IM2 + (IM2−IM1) × α cannot be set. In such an image generation system, overexpression represented by IMOD2 = IM2 + (IM2−IM1) × α. It is difficult to realize drive effect processing.

  For example, let us say that the α blending expression allowed in the image generation system is CS × A + CD × B, which is an addition α blending expression, and CS × A−CD × B, which is a subtraction α blending expression.

  In this case, in the method of FIG. 13B, a CS × A−CD × B subtractive α blending equation is set as the α blending equation. Also, AS is set in a double value mode in which a value twice the set value AS is set as the source α value A. Specifically, AS = (1 + α) / 2 is set. The BS is set in a fixed value mode in which the set value BS is set as a fixed destination α value B. Specifically, BS = α is set in the register of the destination α value. Also, IM2 is set as the source color CS, and IM1 is set as the destination color CD.

If α blending is performed in this way,
CS * A-CD * B = CS * (2 * AS) -CD * BS
= CS × (1 + α) −CD × α
= CS + (CS-CD) × α
= IM2 + (IM2-IM1) × α
Therefore, overdrive effect processing can be realized. In other words, even if the formula of IM2 + (IM2-IM1) × α is not prepared as an α blending formula of the image generation system, a general subtractive α blending formula represented by CS × A−CD × B is used. Overdrive effect processing can be realized.

  Further, the overdrive effect processing of the present embodiment may be realized using a triple buffer.

  For example, in FIG. 15, in the first frame (Jth frame), image data IM1 (IMJ) is generated by drawing an object (one or a plurality of objects) in the buffer 2 (image buffer).

  In the next second frame (Kth frame), the object is drawn in the buffer 1 to generate image data IM2 (IMK). Then, α blending is performed based on the generated image data IM2, the image data IM1 in the first frame written in the buffer 2, and the α value α. Then, the image data IMOD2 = IM2 + (IM2-IM1) × α after the overdrive effect processing is written in the buffer 2.

  In the next third frame (Lth frame), an object is drawn in the buffer 3 to generate image data IM3 (IML). Then, α blending is performed based on the generated image data IM3, the image data IM2 in the second frame written in the buffer 1, and the α value α. Then, the image data IMOD3 = IM3 + (IM3−IM2) × α after the overdrive effect processing is written into the buffer 1.

  As shown in FIG. 16, in the next fourth frame (Mth frame), an object is drawn in the buffer 2 to generate image data IM4 (IMM). Then, α blending processing is performed based on the generated image data IM4, the image data IM3 in the third frame written in the buffer 3, and the α value α. Then, the image data IMOD4 = IM4 + (IM4-IM3) × α after the overdrive effect processing is written into the buffer 3.

  15 and 16, three buffers 1, 2, and 3 are prepared, and the roles (drawing buffer and display buffer) of these buffers 1, 2, and 3 are sequentially switched for each frame. Yes. For example, in the third frame, the buffer 3 is set as a drawing buffer (back buffer) in which an object is drawn, and the buffer 2 is set as a display buffer (front buffer) in which image data output to the display unit is written. The In the fourth frame, the buffer 2 is set as a drawing buffer, and the buffer 1 is set as a display buffer.

  If the roles of the buffers 1, 2, and 3 are sequentially switched in this way, useless copy processing of image data between the buffers becomes unnecessary, and the number of processes is reduced, so that the processing load can be reduced.

  As a method for realizing overdrive effect processing, a method using a double buffer is conceivable. In this method, for example, the difference process between the drawing image data in the current frame and the image data after the overdrive effect process in the previous frame is performed to realize the overdrive effect process. However, with this method, if the effect strength of the overdrive effect process is increased, jaggy or the like may occur on the screen.

  On the other hand, according to the technique using the triple buffer, the drawing image data in the previous frame can be saved, and the difference between the drawing image data in the current frame and the saved drawing image data is processed. It can be performed. Accordingly, accurate difference image data can be obtained, and the occurrence of jaggies and the like can be effectively prevented.

  In FIGS. 15 and 16, overdrive effect processing is realized by a method in which the roles of the buffers 1, 2, and 3 are sequentially switched, but the present embodiment is not limited to this. For example, the overdrive effect process may be realized by providing a difference value buffer in addition to the drawing buffer and the display buffer and writing the difference image data IMK-IMJ in the difference value buffer.

  Next, detailed processing of the realization method of the present embodiment will be described using the flowcharts of FIGS. 17 and 18.

  First, the buffer 1 is set as a drawing destination (step S31). Then, geometry processing is performed (step S32), and the object after geometry processing (after perspective transformation) is drawn in the buffer 1 (step S33).

  Next, the buffer 2 is set as a drawing destination (step S34). Then, the image data in the buffer 1 is set to the texture (step S35), and the α value of the texture is set to be invalidated (step S36).

  Next, as described with reference to FIG. 13B, α blending formula CS × A−CD × B is set (step S37). That is, the subtraction α blending equation is set. In the fixed value mode, B = BS = α is set (step S38). In the double value mode, A = 2 × AS = 1 + α is set as the α value of the sprite (primitive surface) (step S39).

  Next, as described with reference to FIG. 14, the texture of the buffer 1 is mapped to the sprite having the divided screen size (or screen size), and the set α blending is performed on the buffer 2 in which the image data one frame before is drawn. A sprite is drawn according to the equation (step S40). Then, the image in the buffer 2 is displayed on the display unit (step S41).

  Next, the buffer 3 is set as an object drawing buffer, the buffer 1 is set as a display buffer, and the same processing as steps S31 to S41 is performed (steps S42 to S52). Next, the buffer 2 is set as an object drawing buffer, the buffer 3 is set as a display buffer, and the same processing as steps S31 to S41 is performed (steps S53 to S63). By doing so, overdrive effect processing using a triple buffer can be realized as described with reference to FIGS.

2.4 Overdrive effect processing to a specific area When overdrive is performed using a hardware overdrive circuit, overdrive is applied to all areas of the display screen.

  However, depending on the game, it may be sufficient if the afterimage feeling can be reduced only for a specific object in the screen. For example, it may be sufficient if the afterimage feeling can be reduced only for an object such as a character that moves at high speed in the screen, or an object having a shape in which an afterimage is likely to occur (for example, columnar objects arranged side by side). In such a case, if the target of overdrive effect processing is limited to such objects, the processing load may be reduced.

  Therefore, in FIG. 19A, overdrive effect processing is performed only on image data in a specific area 200 in the display area of the display unit. In this way, it is not necessary to perform overdrive effect processing outside the specific area 200. Therefore, for example, when overdrive effect processing is realized by a pixel shader technique, it is possible to reduce the processing load. Further, it is possible to prevent the situation where the overdrive effect processing is unnecessarily applied to a place where the overdrive effect processing is unnecessary.

  The specific area 200 in FIG. 19A can be set based on an object to be drawn in the drawing buffer. Specifically, in the case where image data is generated by drawing a plurality of objects (for example, objects after perspective transformation), an area containing a specific object (model object) among the plurality of objects Execute overdrive effect processing. For example, in FIG. 19B, an area 200 containing a specific object OB is set. Specifically, an area 200 is set based on the vertex coordinates (control point coordinates) of the object (the object after perspective transformation), and overdrive effect processing is performed on the area 200.

  Note that, when a simple object is set for an object, an area 200 for performing overdrive effect processing may be set based on the vertex coordinates of the simple object (simple object after perspective transformation). That is, depending on the game, a simple object (an object that has fewer vertices than the object and moves following the object) may be set for the object. For example, whether or not an attack such as a bullet or punch hits an object is realized by performing a hit check between a simple object and a bullet or punch. If the area 200 is set based on the vertex coordinates of the simple object, the processing load can be reduced because the number of vertices of the simple object is small.

  The setting of the area 200 in FIG. 19B can be specifically realized by the following method. First, a bounding box BB (bounding volume) containing the object OB (or simple object) is generated. This bounding box BB obtains the X coordinate and Y coordinate of the vertex (the vertex of OB after perspective transformation) in the screen coordinate system of the object OB, and the minimum value XMIN, maximum value XMAX of the X coordinate of these vertexes, and Y It can be generated by obtaining the minimum value YMIN and the maximum value YMAX of the coordinates. In order to provide a margin, the size of the bounding box BB may be set slightly larger than that in FIG.

  Then, the primitive plane PL shown in FIG. 14 is set by the generated bounding box BB. Next, the texture of the image data IM2 is mapped to this primitive plane PL. Then, the primitive surface PL to which the texture is mapped is α blended with respect to the buffer in which the image data IM1 (IMOD1) is drawn, thereby generating image data on which the overdrive effect processing has been performed.

  Note that the setting of the region 200 is not limited to the method using the bounding box as shown in FIG. For example, an area at the same position in the display area may be always set as the area 200 for performing the overdrive effect process.

2.5 Adjustment screen, mode setting screen In a home game device, various types of display units may be connected to the game device body. For example, a cathode ray tube television or a liquid crystal television is connected. In addition, a liquid crystal television with a built-in overdrive circuit is connected, or a liquid crystal television without a built-in circuit is connected. Some LCD TVs have slow or fast liquid crystal response speeds. Also, in the portable game device, the specifications of the liquid crystal screen may be changed even for the same product. In some cases, the portable game device is connected to an external monitor, such as a cathode ray tube television or a liquid crystal television.

  In such a case, if the α value (effect intensity) of the overdrive effect processing is a fixed value, the overdrive effect processing is insufficient and an afterimage remains, or flicker (vibration) occurs due to excessive overdrive effect processing. May occur. If the overdrive effect process cannot be enabled or disabled, the overdrive effect process may occur even though the display unit does not require the overdrive effect process.

  20A and 20B, an adjustment screen for adjusting the α value of the overdrive effect processing and a mode setting screen for setting whether or not to enable the overdrive effect processing are displayed. I have to.

  For example, in FIG. 20A, the object OB set to the intermediate color CN2 moves on the background area 210 (adjustment window) of the adjustment screen set to the intermediate color CN1. As described above, if the background area 210 and the object OB are set to an intermediate color that is not a primary color, an afterimage becomes conspicuous, and an adjustment screen suitable for adjusting the α value in overdrive effect processing can be provided.

  While viewing the image of the object OB, the player moves the adjustment slider 212 displayed on the screen with the operation unit to adjust the α value (effect intensity) of the overdrive effect process. For example, when the player feels that the afterimage of the object OB is large, the player moves the adjustment slider 212 to the right side and sets the α value so that the effect intensity of the overdrive effect process is increased. On the other hand, if the afterimage of the object OB is not so large and the effect of overdrive is felt to be too great, the adjustment slider 212 is moved to the left to set the α value so that the effect intensity of the overdrive effect process is reduced. The α value (effect intensity) adjusted in this way is stored in a portable information storage device such as a storage unit or a memory card of the image generation system. In the game screen, overdrive effect processing is performed based on the stored α value (effect intensity).

  Note that the display method of the adjustment screen is not limited to FIG. For example, although a circular object is moved in FIG. 20A, an object having a shape other than a circle (for example, a column shape) may be moved. A plurality of objects may be moved. Alternatively, only the adjustment slider 212 (display object for specifying the adjustment value) may be displayed without displaying such an object. Various colors can be adopted as the intermediate color set for the background area 210 and the object OB. For example, the image of the background area 210 or the object OB may be an image having two or more intermediate colors.

  The mode setting screen in FIG. 20B is a screen for performing various settings in the game. For example, it is a screen for setting game sounds (tone color, volume, stereo / monaural settings), operation unit settings (button and lever assignment settings), image display settings, and the like.

  On the mode setting screen of FIG. 20B, the player can set the overdrive effect processing to be valid (on) or invalid (off) by operating the operation unit. When the setting (selection) for enabling the overdrive effect process is performed, the overdrive effect process is performed on the game screen.

  Note that the display method of the mode setting screen is not limited to FIG. For example, the setting for enabling / disabling overdrive effect processing may be performed on the adjustment screen of FIG. In this case, for example, when the adjustment slider 212 in FIG. 20A is moved to the leftmost side, the overdrive effect process may be invalidated. Further, the effect intensity of the overdrive effect process may be adjusted on the mode setting screen. In this case, for example, the adjustment slider 212 in FIG. 20A may be displayed on the mode setting screen in FIG.

3. Hardware Configuration FIG. 21 shows an example of a hardware configuration capable of realizing this embodiment. The main processor 900 operates based on a program stored in a CD 982 (information storage medium), a program downloaded via the communication interface 990, a program stored in the ROM 950, or the like, and includes game processing, image processing, sound processing, and the like. Execute. 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 to the drawing processor 910 and, if necessary, transfers the texture to the texture storage unit 924. 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 CD drive 980 accesses a CD 982 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 part of this embodiment can be realized by both hardware and a program. In this case, the information storage medium stores a program for causing the hardware (computer) to function as each part of this embodiment. . More specifically, the program instructs the processors 900, 902, 904, 906, 910, and 930, which are hardware, to pass data if necessary. Each processor 900, 902, 904, 906, 910, 930 implements the processing of each unit of the present invention based on the instruction and the passed data.

  Although the present embodiment has been described in detail as described above, it will be easily understood by those skilled in the art that many modifications can be made without departing from the novel matters and effects of the present invention. Accordingly, all such modifications are intended to be included in the scope of the present invention. For example, in the specification or the drawings, terms (first, second, third frames, etc.) described at least once together with different terms (J, K, L, etc.) having a broader meaning or the same meaning are used. The different terms can be used anywhere in the specification or drawings.

  Further, the method for realizing the overdrive effect processing is not limited to that described in the present embodiment, and methods equivalent to these are also included in the scope of the present invention. The overdrive effect processing of the present invention is also applicable when the display unit is not a liquid crystal display device.

  The present invention can be applied to various games. 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 game images, and a mobile phone. it can.

The example of a functional block diagram of the image generation system of this embodiment. 2A, 2B, and 2C are explanatory diagrams of the principle of overdrive effect processing. An operation flow for explaining overdrive effect processing. The operation | movement flow explaining the overdrive effect process using a difference softening process. FIGS. 5A and 5B are explanatory diagrams of the generation of an afterimage of an object. 6 (A) and 6 (B) are explanatory diagrams of occurrence of an afterimage of an object. 7A and 7B are explanatory diagrams of overdrive effect processing. 8A and 8B are explanatory diagrams of overdrive effect processing. 9A and 9B are explanatory diagrams of overdrive effect processing. 10A and 10B are explanatory diagrams of overdrive effect processing. The flowchart of the overdrive effect process performed per pixel. Explanatory drawing of the method of changing an effect intensity coefficient based on a difference image data value. FIGS. 13A and 13B are explanatory diagrams of a method for realizing overdrive effect processing. Explanatory drawing of the method of mapping (alpha) blending drawing by mapping a texture on a primitive surface. Explanatory drawing of the implementation method using a triple buffer. Explanatory drawing of the implementation method using a triple buffer. The flowchart of the implementation method of an overdrive effect process. The flowchart of the implementation method of an overdrive effect process. 19A and 19B are explanatory diagrams of a method for performing overdrive effect processing on a specific area of the display area. 20A and 20B are examples of an adjustment screen and mode setting screen for overdrive effect processing. Hardware configuration example.

Explanation of symbols

100 processing unit, 110 object space setting unit, 112 movement / motion processing unit,
114 virtual camera control unit, 116 display control unit, 120 drawing unit,
122 overdrive effect processing unit, 130 sound generation unit, 160 operation unit,
170 storage unit, 171, 172, 173 first, second, third buffer,
174 texture storage unit, 176 Z buffer, 180 information storage medium,
190 display unit, 192 sound output unit, 194 portable information storage device, 196 communication unit

Claims (12)

A program for generating an image,
A drawing unit that draws an object and generates image data;
As an overdrive effect processing unit that performs overdrive effect processing on the generated image data and generates image data for output to the display unit,
Make the computer work,
The overdrive effect processing unit
Based on the image data IMK generated in the Kth frame, the image data IMJ generated by drawing an object in the J (K> J) frame, and the α value α, IMK + (IMK−IMJ ) A program that generates image data subjected to overdrive effect processing by performing α blending processing of × α. In claim 1,
The overdrive effect processing unit
A texture of the image data IMK is mapped to a primitive surface having a screen size or a divided screen size in which an α value is set, and the primitive surface to which the texture is mapped is mapped to a buffer in which the image data IMJ is drawn. Program characterized by alpha blending drawing. In claim 1 or 2,
The overdrive effect processing unit
In the double value mode in which a value twice the set value AS is set as the source α value A, AS = (1 + α) / 2 is set, and the set value BS is set as a fixed destination α value B. BS = α is set in the mode, and IMK × A−IMJ × B = IMK × (2 × AS) −IMJ × BS = IMK × (1 + α) −IMJ × α is subtracted α blending drawing. program. In any one of Claims 1 thru | or 3,
The overdrive effect processing unit
In the Kth frame,
The object is drawn in the first buffer to generate the image data IMK. The generated image data IMK, the image data IMJ in the Jth frame written in the second buffer, and the α value α Based on this, the α blending process of IMK + (IMK−IMJ) × α is performed, and the image data subjected to the overdrive effect process is written to the second buffer,
In the Lth frame,
The object is drawn in the third buffer to generate the image data IML. The generated image data IML, the image data IMK in the Kth frame written in the first buffer, and the α value α Based on this, IML + (IML−IMK) × α is blended, and the image data subjected to the overdrive effect processing is written to the first buffer.
In the Mth (M>L> K) frame,
The object is drawn in the second buffer to generate the image data IMM. The generated image data IMM, the image data IML in the Lth frame written in the third buffer, and the α value α Based on this, a program that performs α blending processing of IMM + (IMM-IML) × α and writes the image data subjected to the overdrive effect processing to the third buffer. In any one of Claims 1 thru | or 4,
The overdrive effect processing unit
A program that performs the overdrive effect processing only on image data in a specific area of a display area of a display unit. In any one of Claims 1 thru | or 5,
The drawing unit
Generate image data by drawing multiple objects,
The overdrive effect processing unit
A program characterized in that the overdrive effect processing is performed on an area including a specific object among a plurality of objects. In claim 6,
The overdrive effect processing unit
A program characterized in that the region for performing the overdrive effect processing is set based on vertex coordinates of an object or, when a simple object is set for the object, based on the vertex coordinates of the simple object. In any one of Claims 1 thru | or 7,
As a display control unit that performs display control of an adjustment screen for adjusting the α value of the overdrive effect processing,
Make the computer work,
The overdrive effect processing unit
When the effect intensity is adjusted on the adjustment screen, the overdrive effect processing is performed based on the α value obtained by the adjustment. In claim 8,
The display control unit
A program for performing display control for moving an object set to a second intermediate color on a background area of an adjustment screen set to a first intermediate color. In any one of Claims 1 thru | or 9,
As a display control unit that performs display control of a mode setting screen for setting whether to enable the overdrive effect processing,
Make the computer work,
The overdrive effect processing unit
The program for performing the overdrive effect processing when the setting for enabling the overdrive effect processing is performed on the mode setting screen.   A computer-readable information storage medium, wherein the program according to any one of claims 1 to 10 is stored. An image generation system for generating an image,
A drawing unit that draws an object and generates image data;
Including an overdrive effect processing unit that performs overdrive effect processing on the generated image data and generates image data for output to the display unit,
The overdrive effect processing unit
Based on the image data IMK generated in the Kth frame, the image data IMJ generated by drawing an object in the J (K> J) frame, and the α value α, IMK + (IMK−IMJ The image generation system is characterized by generating image data subjected to overdrive effect processing by performing α blending processing of × α.