JP2009211243A - Program, information storage medium, and image generation system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a program, an information storage medium, and an image generation system for generating an image which can be displayed without destroying its vertical and horizontal balance in each of two screen modes whose aspect rates are different. <P>SOLUTION: This program for generating an image which can be viewed from a virtual camera in an object space is provided to make a computer function as a screen mode determination part for determining a screen mode based on selection input to select the screen mode of either a first screen or a second screen whose aspect rates are different and a plotting part for converting the coordinates of each vertex configuring an object arranged in the object space into a visual point coordinate system, and for converting it into a projective coordinate system for performing drawing process. The plotting part is characterized to adjust the field angle of the virtual camera according to the determined screen mode in converting the coordinates of each vertex into the projective coordinate system. <P>COPYRIGHT: (C)2009,JPO&INPIT

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 viewed from a virtual camera (a given viewpoint) in an object space (virtual three-dimensional space) in which a plurality of polygons are set is known. It is very popular for experiencing so-called virtual reality.

In such an image generation system, when the game screen is displayed with wide screen support, when the wide screen is selected to prevent the characters on the game screen from spreading sideways and the balance of the entire game screen is lost. In addition, there is known a technique that converts the coordinates of each vertex of a polygon representing graphic data of a character into a viewpoint coordinate system using a conversion matrix that is reduced to a reciprocal of the enlargement ratio of the wide screen (for example, Patent Document 1).
Japanese Patent No. 3965705

  However, in the conventional image generation system, the graphic data of the character is a processing target, and the entire screen cannot be processed.

  The present invention has been made in view of the problems as described above, and an object of the present invention is to provide an image that can be displayed without losing the balance between vertical and horizontal directions in each of two screen modes having different aspect ratios. It is another object of the present invention to provide a program, an information storage medium, and an image generation system.

(1) The present invention is a program for generating an image visible from a virtual camera in an object space,
A screen mode determination unit that determines a screen mode based on a selection input for selecting one of the first screen and the second screen having different aspect ratios of the screen;
Convert the coordinates of each vertex constituting the object placed in the object space to the viewpoint coordinate system, further convert it to a projective coordinate system, and let the computer function as a drawing unit that performs drawing processing,
The drawing unit
The angle of view of the virtual camera is adjusted according to the determined screen mode when the coordinates of each vertex are converted into the projected coordinate system.

  The present invention also relates to an image generation system including the above-described units. The present invention is also a computer-readable information storage medium, and relates to an information storage medium storing a program that causes a computer to function as each of the above-described units.

  According to the present invention, at the time of projective transformation (perspective projection transformation), by adjusting the angle of view of the virtual camera according to the determined screen mode, the vertical and horizontal balances can be obtained in each of the two screen modes having different aspect ratios. An image that can be displayed without breaking down can be generated.

(2) In the program and information storage medium according to the present invention,
The second screen is a screen obtained by enlarging the first screen in a horizontal direction,
The drawing unit
When the screen mode is determined to be the second screen, the angle of view in the horizontal direction of the virtual camera is enlarged when the coordinates of each vertex are converted into the projected coordinate system.

  According to the present invention, it is possible to generate an image that can be displayed without breaking the balance between the vertical and horizontal directions in the screen mode expanded in the horizontal direction.

(3) In the program and information storage medium according to the present invention,
The drawing unit
When the screen mode is determined to be the second screen, each of the vertices is based on a projection matrix that is reduced in the horizontal direction of the screen to a reciprocal of the enlargement ratio of the second screen with respect to the first screen. It is characterized in that the coordinates of are converted into a projective coordinate system.

  According to the present invention, it is possible to generate an image that can be displayed without breaking the balance between the vertical and horizontal directions in the screen mode expanded in the horizontal direction.

(4) In the program and information storage medium according to the present invention,
The drawing unit
When the screen mode is determined to be the second screen, the image generated by the drawing process is subjected to a smoothing process and output to the display unit.

  According to the present invention, when the generated image is stretched in the horizontal direction and displayed on the display unit by performing the smoothing process on the generated image in the screen mode expanded in the horizontal direction, It is possible to prevent an unnatural image.

(5) In the program and information storage medium according to the present invention,
The drawing unit
The smoothing process is performed using different parameters according to the determined screen mode.

(6) In the program and information storage medium according to the present invention,
The drawing unit
When the screen mode is determined to be the second screen, the image generated by the drawing process is enlarged in the horizontal direction of the screen with an enlargement ratio smaller than the enlargement ratio of the second screen with respect to the first screen. Output to the display unit.

(7) In the program and information storage medium according to the present invention,
The drawing unit
It is characterized in that textures having different resolutions are mapped to objects according to the determined screen mode.

  According to the present invention, in the screen mode expanded in the horizontal direction, when the image is stretched in the horizontal direction and displayed on the display unit, an unnatural image 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 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 an object (moving body, player character), and functions thereof are a keyboard, a mouse, a lever, a button, a steering, a microphone, a touch panel type display, a casing, and the like. Can be realized.

  In particular, the operation unit 160 of the present embodiment inputs operation data for selecting one of the screen modes of the first screen and the second screen having different screen aspect ratios.

  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 object data storage unit 176 stores object data of objects.

  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. The information storage medium 180 can store 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 communication unit 196 performs various controls for communicating with the outside (for example, other game systems and servers), and functions thereof are hardware such as various processors or communication ASICs, programs, and the like. realizable.

  Note that a program or data for causing a computer to function as each unit of the present embodiment stored in the information storage medium or storage unit of the server is received via the network, and the received program or data is received by the information storage medium 180. Or may be stored in the storage unit 170. The case where the program and data are received and the game system is made to function is also 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 172 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 a screen mode determination unit 108, an object space setting unit 110, a movement / motion processing unit 112, a virtual camera control unit 114, a drawing unit 120, and a sound generation unit 130. Note that some of these may be omitted.

  The screen mode determination unit 108 determines the screen mode based on a selection input for selecting one of the first screen and the second screen having different screen aspect ratios from the operation unit 160.

  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. For example, the position and rotation angle (synonymous with the direction and direction of the object in the world coordinate system, for example, rotation when rotating clockwise when viewed from the positive direction of each axis of the X, Y, and Z axes in the world coordinate system. The angle is determined, and the object is arranged at the position (X, Y, Z) at the rotation angle (rotation angle about the X, Y, Z axis).

  The movement / motion processing unit 112 performs a movement / motion calculation (movement / motion simulation) of an object (character, moving object, etc.). In other words, based on operation data input by the player through the operation unit 160, a program (movement / motion algorithm), various data (motion data), a physical law, or the like, the object is moved in the object space or the object is moved ( (Motion, animation). 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, based on operation data input by the player through the operation unit 160, a program (movement / motion algorithm), or the like, the position (X, Y, Z) or rotation angle (for example, the virtual camera in the world coordinate system) A process of controlling the rotation angle in the case where the X, Y, and Z axes rotate clockwise as viewed from the positive direction is performed. In short, processing for controlling the viewpoint position, the line-of-sight direction, and the angle of view is performed.

  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. When generating a so-called three-dimensional game image, first, object data (model data) including vertex data (vertex position coordinates, texture coordinates, color data, normal vector, α value, etc.) of each vertex of the object (model) ) Is input, and vertex processing (shading by a vertex shader) is performed based on the vertex data included in the input object data. When performing the vertex processing, vertex generation processing (tessellation, curved surface division, polygon division) for re-dividing the polygon may be performed as necessary.

  In the vertex processing, according to the vertex processing program (vertex shader program, first shader program), vertex movement processing, coordinate transformation, for example, world coordinate transformation, visual field transformation (camera coordinate transformation), clipping processing, projective transformation (perspective transformation) , Projection conversion), viewport conversion (screen coordinate conversion), light source calculation, and other geometric processing are performed, and based on the processing results, the vertex data given to the vertex group constituting the object is changed (updated, adjusted). To do. Object data after the geometry processing (position coordinates of object vertices, texture coordinates, color data (luminance data), normal vector, α value, etc.) is stored in the object data storage unit 176.

  In particular, the drawing unit 120 according to the present embodiment converts the coordinates of each vertex constituting an object arranged in the object space into a viewpoint coordinate system (view conversion), and further converts into a projective coordinate system (projection conversion) to perform drawing processing. The angle of view of the virtual camera is adjusted according to the screen mode determined by the screen mode determination unit 108 when the coordinates of each vertex are converted into the projected coordinate system.

  In addition, when the second screen is a screen obtained by enlarging the first screen in the horizontal direction, and the screen mode determination unit 108 determines that the screen mode is the second screen, the drawing unit 120 The angle of view of the virtual camera in the horizontal direction of the screen may be enlarged when the coordinates of the vertices are converted into the projected coordinate system.

  In addition, when the screen mode determination unit 108 determines the screen mode to be the second screen, the drawing unit 120 is the reciprocal times the magnification of the second screen with respect to the first screen in the horizontal direction of the screen. The coordinates of each vertex may be converted into a projected coordinate system based on a projection matrix that is reduced to

  Then, rasterization (scan conversion) is performed based on the vertex data after the vertex processing, and the surface of the polygon (primitive) is associated with the pixel. Subsequent to rasterization, pixel processing (shading or fragment processing by a pixel shader) for drawing pixels (fragments forming a display screen) constituting an image is performed. In pixel processing, according to a pixel processing program (pixel shader program, second shader program), various processes such as texture reading (texture mapping), color data setting / change, translucent composition, anti-aliasing, etc. are performed, and an image is processed. The final drawing color of the constituent pixels is determined, and the drawing color of the perspective-transformed object is output (drawn) to the drawing buffer 174 (a buffer capable of storing image information in units of pixels; VRAM, rendering target). That is, in pixel processing, per-pixel processing for setting or changing image information (color, normal, luminance, α value, etc.) in units of pixels is performed. Thereby, an image that can be seen from the virtual camera (given viewpoint) in the object space is generated. Note that when there are a plurality of virtual cameras (viewpoints), an image can be generated so that an image seen from each virtual camera can be displayed as a divided image on one screen.

  In particular, when the screen mode determination unit 108 determines the screen mode to be the second screen, the rendering unit 120 of the present embodiment performs a smoothing process (anti-aliasing) on the image generated by the rendering process. May be output to the drawing buffer 174.

  The drawing unit 120 may perform the smoothing process using different parameters according to the determined screen mode.

  In addition, when the screen mode is determined to be the second screen, the drawing unit 120 displays the image generated by the drawing process in the horizontal direction of the screen from the enlargement ratio of the second screen with respect to the first screen. The image may be enlarged and output to the display unit 190 with a small magnification.

  Note that the vertex processing and pixel processing are realized by hardware that enables polygon (primitive) drawing processing to be programmed by a shader program written in a shading language, so-called programmable shaders (vertex shaders and pixel shaders). Programmable shaders can be programmed with vertex-level processing and pixel-level processing, so that the degree of freedom of drawing processing is high, and expressive power is greatly improved compared to conventional hardware-based fixed drawing processing. Can do.

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

  Texture mapping is a process for mapping a texture (texel value) stored in the texture storage unit 178 of the storage unit 170 to an object. Specifically, the texture (surface properties such as color (RGB) and α value) is read from the texture storage unit 178 of the storage unit 170 using the texture coordinates set (given) at the vertex of the object. Then, a texture that is a two-dimensional image is mapped to an object. In this case, processing for associating pixels with texels, bilinear interpolation or the like is performed as texel interpolation.

  In particular, the drawing unit 120 of this embodiment may read out textures having different resolutions from the texture storage unit 178 according to the screen mode determined by the screen mode determination unit 108 and map them to the object.

  As the hidden surface removal processing, hidden surface removal processing by a Z buffer method (depth comparison method, Z test) using a Z buffer 179 (depth buffer) in which a Z value (depth information) of a drawing pixel is stored may be performed. it can. That is, when drawing pixels corresponding to the primitive of the object are drawn, the Z value stored in the Z buffer 179 is referred to. Then, the Z value of the referenced Z buffer 179 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 179 is updated to a new Z value.

  α blending (α synthesis) is a translucent synthesis process (usually α blending, addition α blending, subtraction α blending, or the like) based on an α value (A value).

  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.

  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).

2. Next, the method of this embodiment will be described with reference to the drawings.

2-1. Adjustment of angle of view of virtual camera FIGS. 2A and 2B are diagrams for explaining projective transformation.

  In this embodiment, a normal screen (first screen) with an aspect ratio (aspect ratio) of 4: 3 and a wide screen (second screen) with an aspect ratio of 16: 9 are prepared as screen modes. The screen mode is determined by the selection input by.

  Then, when the coordinates of each vertex constituting the object arranged in the object space are converted into the viewpoint coordinate system (field conversion) and further converted into the projective coordinate system (projection conversion), depending on the determined screen mode Adjust the angle of view of the virtual camera.

  That is, a view volume having a different shape is set in the viewpoint coordinate system according to the determined image mode. Specifically, when the screen mode is determined to be a normal screen, as shown in FIG. 2A, a view volume VV1 with an aspect ratio (w / h) of 4/3 is set as the viewpoint coordinate system. When the wide screen is selected as the screen mode, as shown in FIG. 2B, the view volume VV2 having an aspect ratio (w / h) of 16/9 is set in the viewpoint coordinate system. The view volume VV2 shown in FIG. 2B has an angle of view (viewing angle) θx in the X-axis direction of the virtual camera VC that is 4/3 times larger than the view volume VV1 shown in FIG. Yes.

  Here, the projective transformation from the viewpoint coordinate system to the projective coordinate system is performed based on a projection matrix R (conversion matrix), and the projection matrix R can be expressed by the following equation.

  The parameter n is the Z coordinate value of the near plane surface NP (clip plane near the virtual camera VC), and the parameter f is the Z coordinate value of the far plane surface FP (clip plane far from the virtual camera VC). The parameters l and r are the X coordinate values of the left end and the right end of the near plane surface NP, respectively, and the parameters t and b are the Y coordinate values of the upper end and the lower end of the near plane surface NP, respectively.

  In this embodiment, when the screen mode is determined to be a normal screen, the projection matrix R is obtained by setting each parameter so that the aspect ratio (rl) / (tb) is 4/3. When the screen mode is determined to be a wide screen, the projection matrix R is obtained by setting each parameter so that the aspect ratio (rl) / (tb) is 16/9.

  The coordinates of each vertex constituting the object in the view volume are converted into a projective coordinate system CC (clip coordinate system) shown in FIG. 3 by projective transformation, and further converted into a screen coordinate system by viewport transformation.

  4A and 4B are diagrams for explaining the screen coordinate system. FIG. 4A shows an object OB in the screen coordinate system SC when the screen mode is determined as a normal screen, and FIG. 4B shows the screen coordinates when the screen mode is determined as a wide screen. An object OB in the system SC is shown.

  In the screen coordinate system SC of the present embodiment, the aspect ratio of the viewport VP is 4/3, and the area is 0 to 640 in the X axis direction and 0 to 480 in the Y axis direction, and the drawing buffer 174 (rendering target) ) Region (640 × 480).

  As shown in FIG. 4A, when the screen mode is a normal screen, the aspect ratio of the view volume VV1 and the aspect ratio of the viewport VP at the time of projective conversion coincide with each other. There is no change in the vertical and horizontal balance of the object OB.

  On the other hand, as shown in FIG. 4B, when the screen mode is a wide screen, the aspect ratio of the view volume VV2 at the time of projective conversion is 16/9, whereas the aspect ratio of the viewport Is 4/3, the object OB in the screen coordinate system SC is reduced in the X-axis direction (screen horizontal direction). Specifically, the image is reduced to an inverse number (3/4) of the enlargement ratio (4/3) of the wide screen with respect to the normal screen.

  FIG. 5A and FIG. 5B are examples of game screens displayed on the display unit.

  As shown in FIG. 5A, when the screen mode is determined to be a normal screen, a normal screen NS with an aspect ratio of 4: 3 is displayed on the display unit 190. As shown in FIG. 5B, when the screen mode is determined to be a wide screen, a wide screen WS having an aspect ratio of 16: 9 is displayed on the display unit 190.

  In the case of FIG. 5B, the image data having the aspect ratio of 4: 3 stored in the drawing buffer 174 is approximately 1.11 times in the horizontal direction of the screen (wide screen enlargement ratio (4/3) with respect to the normal screen). And is output to the display unit 190. The display unit 190 further enlarges the image by about 1.2 times in the horizontal direction of the screen and displays it as a wide screen WS. Therefore, the object OB reduced in the horizontal direction in the screen coordinate system SC is enlarged 4/3 times in the horizontal direction of the screen on the wide screen WS, and the vertical and horizontal balance is restored to the original.

  Thus, when the screen mode is determined to be a wide screen, projection transformation is performed by enlarging the horizontal angle of view of the virtual camera (such that each vertex of the object is reduced in the horizontal direction in the screen coordinate system). By performing the projective transformation based on the projection matrix), the vertical and horizontal balance can be displayed even on a wide screen enlarged in the horizontal direction.

  In the wide screen mode, image data having an aspect ratio of 4: 3 is output from the drawing buffer 174 to the display unit 190 as it is, and the display unit 190 enlarges the image by a factor of 4/3 in the horizontal direction of the screen and displays it as a wide screen WS. You may make it do.

2-2. Smoothing Process FIG. 6 is a diagram for explaining the smoothing process in the present embodiment.

  In this embodiment, when the screen mode is determined to be a wide screen, the rendered image is subjected to smoothing processing and output to the display unit, and then output to the display unit. To do.

  For example, as shown at A1 in FIG. 6, the original image OI drawn in the drawing buffer 174 is enlarged and drawn in a work buffer larger in size than the drawing buffer 174, and the enlarged image EI drawn in the work buffer is further drawn. Smoothing processing is performed by performing reduction processing and drawing in the drawing buffer 174. Note that a smoothing process may be performed by drawing a work image obtained by shifting the original image in the vertical or horizontal direction in the work buffer and synthesizing the work image with the original image.

  As described above, when the screen mode is determined to be the wide screen, the rendered image is subjected to smoothing processing and output to the display unit 190, whereby the display unit 190 is enlarged in the horizontal direction of the screen. In some cases, it can be a natural image.

  Note that the smoothing process may be performed even during the normal screen, and the parameter values used for the smoothing process may be changed according to the screen mode. For example, when the wide screen is used, the enlargement ratio of the original image OI may be set larger than that during the normal screen so that the smoothing effect is enhanced.

2-3. Texture Mapping FIGS. 7A and 7B are diagrams for describing texture mapping in the present embodiment. 7A shows a texture for a normal screen, and FIG. 7B shows a texture for a wide screen.

  In the present embodiment, textures having different resolutions are mapped to objects according to the determined screen mode.

  For example, in the texture storage unit 176, the normal screen texture NT and the normal screen texture NT are reduced by a factor of 3/4 in the horizontal direction (the horizontal resolution of the normal screen texture NT is reduced). If the texture WT for the wide screen is stored and the screen mode is determined to be a normal screen, the texture NT for the normal screen is mapped to an object, and if the screen mode is determined to be a wide screen The texture WT for the wide screen is mapped to the object.

  As described above, when the screen mode is determined to be the wide screen, the texture that has been reduced in the horizontal direction in advance is mapped to the object in the screen coordinate system (reduced in the horizontal direction). Balance can be maintained. That is, it is possible to prevent the texture from being reduced in the horizontal direction during mapping and the characters represented in the texture from being crushed.

2-4. Level of detail (LOD)
8A and 8B are diagrams for explaining the control of the level of detail (LOD) according to the present embodiment.

  In the present embodiment, drawing processing is performed by controlling the level of detail of an object based on the distance between the virtual camera and the object in the object space. Specifically, if the distance between the virtual camera and the object is within a predetermined threshold, a high-definition object with a level of detail level 1 is drawn for the object. If the distance between the virtual camera and the object exceeds a predetermined threshold value, a low-definition object (an object in which the number of polygons and vertices is reduced) with a level of detail 2 is drawn for the object. Furthermore, in the present embodiment, the threshold value for controlling the level of detail is changed according to the determined screen mode.

  For example, when the screen mode is determined to be a normal screen, a threshold value TH1 is set as shown in FIG. 8A, and when the screen mode is determined to be a wide screen, the screen shown in FIG. As shown, a threshold TH2 closer to the virtual camera VC is set. That is, the objects OB1 and OB2 are drawn with high definition on the normal screen, and only the object OB1 closest to the virtual camera VC is drawn with high definition on the wide screen.

  When the wide screen is used, each vertex constituting the object in the screen coordinate system is reduced in the horizontal direction. Therefore, even if a high-definition object is drawn up to an object that is somewhat distant from the virtual camera VC, the effect is higher than that of the normal screen. Will be reduced. Also, when the screen is wide, the objects visible on the screen are wider than the normal screen, so more vertices must be processed. Therefore, when the screen mode is determined to be a wide screen, the threshold of the level of detail is set lower than that in the normal screen to narrow the range of high-definition drawing, so that it is efficient without unnecessary computation processing. Simple drawing.

3. Processing of this Embodiment Next, an example of processing of this embodiment will be described using the flowchart of FIG.

  First, world coordinate conversion is performed to convert the coordinates of each vertex constituting the object into the world coordinate system (step S10). Next, visual field conversion for converting the coordinates of each vertex into the viewpoint coordinate system is performed (step S12).

  Next, it is determined whether or not the screen mode is a wide screen (step S14). If it is determined that the screen mode is not a wide screen (a normal screen), a view volume having an aspect ratio of 4: 3 is selected from the viewpoint coordinate system. Then, projective transformation is performed to transform the coordinates of each vertex in the view volume into a projected coordinate system (step S16).

  If it is determined in step S14 that the screen mode is the wide screen, the view volume having an aspect ratio of 16: 9 is set as the viewpoint coordinate system, and the coordinates of each vertex in the view volume are converted into the projective coordinate system. Projective transformation is performed (step S18). That is, the projection transformation is performed by enlarging the angle of view of the virtual camera only in the horizontal direction by 4/3 times.

  Next, viewport conversion is performed to convert the coordinates of each vertex into the screen coordinate system (step S20), and drawing processing for outputting the drawing color of the object after coordinate conversion to the drawing buffer is performed (step S22).

  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.

  For example, the case where an image viewed from one virtual camera is displayed on one screen has been described, but an image viewed from each of the two virtual cameras may be displayed on each of the screens divided into two vertically. In this case, when the normal screen is determined as the screen mode, projective transformation is performed with the view volume having an aspect ratio of 8: 3 set as the viewpoint coordinate system, and when the wide screen is determined, the aspect ratio is Projective transformation is performed with the view volume of 32: 9 set in the viewpoint coordinate system. That is, even when the screen is divided into two, at the time of a wide screen, projection conversion is performed by enlarging the angle of view of only the horizontal direction of the virtual camera by 4/3 times.

The example of a functional block diagram of the game system of this embodiment. 2A and 2B are diagrams for explaining projective transformation. The figure which shows a projective coordinate system. 4A and 4B are diagrams for explaining the screen coordinate system. FIG. 5A and FIG. 5B are examples of the game screen displayed on the display unit. The figure for demonstrating a smoothing process. 7A and 7B are diagrams for explaining texture mapping. 8A and 8B are diagrams for explaining the control of the level of detail (LOD). The flowchart figure which shows the flow of the process of this embodiment.

Explanation of symbols

100 processing unit, 108 screen mode determination unit, 110 object space setting unit, 112 movement / motion processing unit, 114 virtual camera control unit, 120 drawing unit, 130 sound generation unit, 160 operation unit, 170 storage unit, 180 information storage medium 190 Display unit 192 Sound output unit 196 Communication unit

Claims (9)

A program for generating an image visible from a virtual camera in an object space,
A screen mode determination unit that determines a screen mode based on a selection input for selecting one of the first screen and the second screen having different aspect ratios of the screen;
Convert the coordinates of each vertex constituting the object placed in the object space to the viewpoint coordinate system, further convert it to a projective coordinate system, and let the computer function as a drawing unit that performs drawing processing,
The drawing unit
A program for adjusting the angle of view of a virtual camera in accordance with the determined screen mode when converting the coordinates of each vertex into a projected coordinate system. In claim 1,
The second screen is a screen obtained by enlarging the first screen in a horizontal direction,
The drawing unit
When the screen mode is determined to be the second screen, the horizontal camera angle of view of the virtual camera is enlarged when the coordinates of each vertex are converted into the projected coordinate system. In claim 2,
The drawing unit
When the screen mode is determined to be the second screen, each of the vertices is based on a projection matrix that is reduced in the horizontal direction of the screen to a reciprocal of the enlargement ratio of the second screen with respect to the first screen. A program characterized by converting the coordinates of to a projective coordinate system. In either claim 2 or 3,
The drawing unit
When the screen mode is determined to be the second screen, the program performs smoothing processing on the image generated by the drawing processing and outputs it to the display unit. In claim 4,
The drawing unit
A program for performing the smoothing process using different parameters according to the determined screen mode. In any of claims 2 to 5,
The drawing unit
When the screen mode is determined to be the second screen, the image generated by the drawing process is enlarged in the horizontal direction of the screen with an enlargement ratio smaller than the enlargement ratio of the second screen with respect to the first screen. Output to the display unit. In any one of Claims 1 thru | or 6.
The drawing unit
A program that maps textures having different resolutions to an object in accordance with a determined screen mode.   A computer-readable information storage medium, wherein the program according to any one of claims 1 to 7 is stored. An image generation system for generating an image visible from a virtual camera in an object space,
A screen mode determination unit that determines a screen mode based on a selection input for selecting one of the first screen and the second screen having different aspect ratios of the screen;
A drawing unit that converts coordinates of each vertex constituting the object arranged in the object space into a viewpoint coordinate system, and further converts into a projected coordinate system to perform a drawing process,
The drawing unit
An image generation system that adjusts the angle of view of a virtual camera in accordance with a determined screen mode when converting the coordinates of each vertex into a projected coordinate system.

Images