JP4575937B2 - Image generating apparatus, image generating method, and program - Google Patents

Description

  The present invention relates to an image generation apparatus, an image generation method, and a program suitable for expressing the reflection of an object while making it easy to recognize the position and shape of the object.

When generating an image representing a virtual space, there is a method of drawing the reflection of an object on a reflective surface such as a floor in order to express it more realistically. For example, Patent Document 1 discloses a technique for drawing a reflection with a reduced processing burden by omitting drawing on a primitive surface that exists in a reflection direction that is impossible when an object is viewed from a virtual viewpoint. It is disclosed.
Japanese Patent No. 3377490

  However, in the conventional method as shown in Patent Document 1, an image that is simply faithfully reflected by a virtual mirror is used as a reflected image regardless of the position and shape of the object, so that a portion near the reflecting surface is also far away. The part will be reflected in the same way. As a result, there is a problem that the image becomes complicated and difficult to see as a whole, and it becomes difficult to distinguish between the image of the object body and the mirror image of the reflection, and it becomes difficult to recognize the position and shape of the object body. .

  The present invention solves such problems, and provides an image generation apparatus, an image generation method, and a program suitable for expressing the reflection of an object while making it easy to recognize the position and shape of the object. The purpose is to do.

  In order to achieve the above object, the following invention is disclosed in accordance with the principle of the present invention.

An image generation apparatus according to a first aspect of the present invention includes a position shape storage unit, a texture storage unit, a mirror image calculation unit, a transparency acquisition unit, and a generation unit.
The position shape storage unit stores the position and shape of the model object arranged in the virtual space, and the position and shape of the plane object.
The texture storage unit stores a first texture to be pasted on the surface of the model object.
The mirror image calculation unit calculates the position and shape of the mirror image object obtained by inverting the model object with respect to the surface object based on the position and shape of the model object and the surface object stored in the position shape storage unit. calculate.
The transparency acquisition unit, according to each distance from the surface object stored in the position shape storage unit to each region constituting the surface of the mirror image object calculated by the mirror image calculation unit, the first for each region Get the transparency of the texture.
The generation unit obtains a projection destination of the model object and the mirror image object with respect to the projection plane arranged in the virtual space, and stores the first destination stored in the texture storage unit in the projection destination of each region of the mirror image object. The portion corresponding to each region of the texture is pasted with the transparency acquired by the transparency acquisition unit, the first texture stored in the texture storage unit is pasted to the projection destination of the model object, and the image is Generate.
With these configurations, the object's image can have a part that is clearly reflected or blurred due to the distance to the reflecting surface, and the three-dimensional position and shape of the object can be easily grasped by the difference in transparency of the reflection, and The image is not complicated. For example, when generating a reflection image on the reflection surface of an object, a dependency relationship is determined in advance between the transparency set for the reflection image and the distance between each part of the reflection image and the reflection surface. Keep it. The image generation device changes the transparency of each part of the reflected image so as to satisfy this dependency. Then, the user can grasp how far each part of the object body corresponding to each part of the reflected image is away from the reflecting surface based on the dependency, based on the difference in transparency.

The transparency acquisition unit may increase the transparency as the distance from the plane object to the mirror image object is longer.
With these configurations, the reflection of the object becomes transparent as the distance from the reflection surface increases, and the object becomes opaque as the distance from the reflection surface increases. Therefore, a three-dimensional reflection can be expressed, and the user can easily grasp the sense of distance. For example, it can be readily seen that the part of the object body corresponding to the part where the reflection is clear is close to the reflection surface, and the part of the object body corresponding to the part where the reflection is not clear is far from the reflection surface.

The transparency acquisition unit may monotonously increase the transparency with respect to the distance from the plane object to the mirror image object.
In this case, the reflection of the object becomes transparent as the distance from the reflection surface increases, and the reflection of the object becomes opaque as the distance from the reflection surface approaches. Further, the transparency may be a monotonically increasing tendency as a whole, and may take a constant value in a certain arbitrary distance section. For example, the transparency can be changed to give a predetermined number of gradations. The image generation apparatus can express a three-dimensional reflection, and the user can easily grasp the sense of distance.

The texture storage unit may further store a second texture to be pasted on the surface of the plane object.
Then, the generation unit pastes the second texture on the surface of the plane object, and then, among the first textures stored in the texture storage unit, in the projection destination of each region of the mirror image object The part corresponding to each area is pasted with the transparency acquired by the transparency acquisition unit, and then the first texture stored in the texture storage unit is pasted to the projection destination of the model object, and the image is It may be generated.
With these configurations, a realistic image can be generated. That is, the object image and the reflected image of the object image on the reflection surface are not overwritten with the image of the reflection surface and are not seen. Further, no matter where the viewpoint is located, the object image is not overwritten by the reflected image and cannot be seen.

An image generation method according to another aspect of the present invention is an image generation method executed by an image generation apparatus having a position shape storage unit, a texture storage unit, a mirror image calculation unit, a transparency acquisition unit, and a generation unit, A calculation step, a transparency acquisition step, and a generation step are provided.
The position shape storage unit stores the position and shape of the model object arranged in the virtual space and the position and shape of the plane object.
The texture storage unit stores a texture to be pasted on the surface of the model object.
The mirror image calculation step includes a mirror image object obtained by inverting the model object with respect to the plane object based on the position and shape of the model object and the plane object stored in the position shape storage unit. Calculate the position and shape.
The transparency acquisition step is performed by the transparency acquisition unit for each area according to the distance from the plane object stored in the position shape storage unit to each area constituting the surface of the mirror image object calculated by the mirror image calculation step. Change the transparency of the texture.
In the generation step, the generation unit obtains the projection destination of the model object and the mirror image object with respect to the projection plane arranged in the virtual space, and is stored in the texture storage unit in the projection destination of each region of the mirror image object. The portion corresponding to each area of the texture is pasted with the transparency acquired in the transparency acquisition step, and the texture stored in the texture storage unit is pasted to the projection destination of the model object to generate an image. .
With these configurations, the object's image can have a part that is clearly reflected or blurred due to the distance to the reflecting surface, and the three-dimensional position and shape of the object can be easily grasped by the difference in transparency of the reflection, and The image is not complicated.

A program according to another aspect of the present invention causes a computer to function as a position shape storage unit, a texture storage unit, a mirror image calculation unit, a transparency acquisition unit, and a generation unit.
The position shape storage unit stores the position and shape of the model object arranged in the virtual space, and the position and shape of the plane object.
The texture storage unit stores a texture to be pasted on the surface of the model object.
The mirror image calculation unit calculates the position and shape of the mirror image object obtained by inverting the model object with respect to the surface object based on the position and shape of the model object and the surface object stored in the position shape storage unit. calculate.
The transparency acquisition unit acquires the transparency of the texture for each region according to the distance from the surface object stored in the position shape storage unit to each region constituting the surface of the mirror image object calculated by the calculation unit. To do.
The generation unit obtains the projection destination of the model object and the mirror image object on the projection plane arranged in the virtual space, and includes the texture stored in the texture storage unit at the projection destination of the region of the mirror image object. A portion corresponding to each region is pasted with the transparency acquired by the transparency acquisition unit, and a texture stored in the texture storage unit is pasted on the projection destination of the model object to generate an image.
With these configurations, the object's image can have a part that is clearly reflected or blurred due to the distance to the reflecting surface, and the three-dimensional position and shape of the object can be easily grasped by the difference in transparency of the reflection, and The image is not complicated.

  According to the present invention, the reflection of an object can be expressed while making it easy to recognize the position and shape of the object.

  FIG. 1 is a schematic diagram showing a schematic configuration of a typical game device in which an image generation device according to an embodiment of the present invention is realized. Hereinafter, a description will be given with reference to FIG.

  The game apparatus 100 includes a CPU (Central Processing Unit) 101, a ROM (Read Only Memory) 102, a RAM (Random Access Memory) 103, an interface 104, a controller 105, an external memory 106, and a DVD (Digital Versatile Disk). ) -ROM drive 107, image processing unit 108, audio processing unit 109, and NIC (Network Interface Card) 110.

  Note that a DVD-ROM storing a game program and data is loaded into the DVD-ROM drive 107, and the game apparatus 100 is turned on to execute the program. Realized.

  The CPU 101 controls the overall operation of the game apparatus 100 and is connected to each component to exchange control signals and data.

  The ROM 102 records an IPL (Initial Program Loader) that is executed immediately after the power is turned on, and the CPU 101 reads the program recorded on the DVD-ROM into the RAM 103 and executes it. The ROM 102 stores an operating system program and various data necessary for operation control of the entire game apparatus 100, and the CPU 101 reads out and executes these programs.

  The RAM 103 is for temporarily storing data and programs, and holds programs and data read from the DVD-ROM and other data necessary for the progress of the game.

  The controller 105 connected via the interface 104 receives an operation input performed when the user executes the game. For example, the controller 105 is provided with an A button, a B button, an X button, a Y button, direction buttons (direction keys) indicating four directions, and the like. When these buttons are pressed by the user, an operation input corresponding to the pressed button is accepted.

  In the external memory 106 detachably connected via the interface 104, data indicating the progress of the game, communication log (record) data, and the like are stored in a rewritable manner. The user can record these data in the external memory 106 as appropriate by inputting an instruction via the controller 105.

  A DVD-ROM mounted on the DVD-ROM drive 107 stores a program for realizing the game and image data and sound data associated with the game. Under the control of the CPU 101, the DVD-ROM drive 107 performs a reading process on the DVD-ROM loaded therein, reads out necessary programs and data, and these are temporarily stored in the RAM 103 or the like.

  The image processing unit 108 processes the data read from the DVD-ROM by the CPU 101 or an image arithmetic processor (not shown) included in the image processing unit 108, and then processes the processed data on a frame memory ( (Not shown). The image information recorded in the frame memory is converted into a video signal at a predetermined synchronization timing and output to a monitor (not shown) connected to the image processing unit 108. Thereby, various image displays are possible.

The image calculation processor can execute a two-dimensional image overlay calculation, a transmission calculation such as α blending, and various saturation calculations at high speed.
In addition, the polygon information arranged in the virtual three-dimensional space and added with various kinds of texture information is rendered by the Z buffer method, and a rendered image is obtained by overlooking the polygon arranged in the virtual three-dimensional space from a predetermined viewpoint position. High speed execution of the obtained operation is also possible.

  Further, the CPU 101 and the image arithmetic processor operate in a coordinated manner, so that a character string can be drawn as a two-dimensional image in a frame memory or drawn on the surface of each polygon according to font information defining the character shape. is there. The font information is recorded in the ROM 102, but it is also possible to use dedicated font information recorded in the DVD-ROM.

  The audio processing unit 109 converts audio data read from the DVD-ROM into an analog audio signal, and outputs the analog audio signal from a speaker (not shown) connected thereto. Further, under the control of the CPU 101, sound effects and music data to be generated during the progress of the game are generated, and sound corresponding to this is output from the speaker.

  The NIC 110 is for connecting the game apparatus 100 to a computer communication network (not shown) such as the Internet, and conforms to the 10BASE-T / 100BASE-T standard used when configuring a LAN (Local Area Network). Therefore, analog modems for connecting to the Internet using telephone lines, ISDN (Integrated Services Digital Network) modems, ADSL (Asymmetric Digital Subscriber Line) modems, cables for connecting to the Internet using cable television lines A modem or the like, and an interface (not shown) that mediates between them and the CPU 101 are configured.

In addition, the game apparatus 100 uses a large-capacity external storage device such as a hard disk so that the ROM 102, the RAM 103, the external memory 106, the DVD-ROM attached to the DVD-ROM drive 107, and the like function. It may be configured.
In addition, it is possible to adopt a form in which an input / output device such as a keyboard for receiving a character string editing input from a user and a mouse for receiving various position designations and selection inputs is connected.

  Further, instead of the game apparatus 100 of the present embodiment, a general computer (general-purpose personal computer or the like) can also be used as the image generation apparatus according to the present invention. For example, a general computer, like the game device 100, includes a CPU, RAM, ROM, DVD-ROM drive, and NIC, and includes an image processing unit that has simpler functions than the game device 100. In addition to having a hard disk as an external storage device, a flexible disk, a magneto-optical disk, a magnetic tape, and the like can be used. In addition, a keyboard, a mouse or the like is used as an input device instead of a controller. Then, after the game program is installed, the program can be executed to function as an image generation device.

  Next, a functional schematic configuration of the image generation apparatus 200 according to the present embodiment will be described. FIG. 2 is a diagram illustrating a schematic configuration of the image generation apparatus 200. The image generation apparatus 200 includes a position shape storage unit 201, a texture storage unit 202, a mirror image calculation unit 203, a transparency acquisition unit 204, and a generation unit 205.

  As illustrated in FIG. 3, the image generation apparatus 200 according to the present embodiment generates an image including a model object 310, a plane object 320, and a mirror image object 330 that are arranged in a virtual space.

  The model object 310 is, for example, a character object that represents a human model that performs gymnastics or exercise. The plane object 320 is an object representing a mirror, a light reflection plate, a glass window, or the like installed on the floor or stage on which the model object 310 is placed, or a side surface. The mirror image object 330 is a character object that is arranged as if the model object 310 appears in the plane object 320. As an example, the image generation apparatus 200 is a studio in a virtual space where a fitness instructor (model object 310) exercises on a stage that reflects light (plane object 320) and reflects on the instructor's stage. An image representing the inside of the studio together with the appearance (mirror image object 330) is generated by image generation processing described later.

  The position shape storage unit 201 stores the position and shape of the model object 310 arranged in the virtual space, and the position and shape of the plane object 320. These initial values are stored in advance in, for example, a DVD-ROM, and the CPU 101 reads out the DVD-ROM loaded in the DVD-ROM drive 107 and temporarily stores it in the RAM 103. The CPU 101 can update the temporarily stored data indicating the position and shape as needed, for example, according to the progress of the game. The CPU 101, the RAM 103, and the DVD-ROM drive 107 work together to function as the position shape storage unit 201.

  The shapes of the model object 310 and the plane object 320 are expressed as numerical data by dividing the surfaces into polygons (primitives) of minute polygons (typically triangles and quadrangles).

  The positions of the model object 310 and the plane object 320 are represented by the coordinates (r, θ, φ) of the representative points in each object using a polar coordinate system using one moving radius and two declination angles. . For example, the coordinate value of the barycentric point of each object becomes the coordinate value indicating the position of the representative point of each object. However, the coordinate system is not limited to this, and for example, an orthogonal coordinate system with three axes orthogonal to each other may be used. Alternatively, a configuration may be adopted in which coordinate calculation or the like is performed by separately setting a global coordinate system (world coordinate system) representing the entire virtual space and a local coordinate system (body coordinate system) for each object.

  The texture storage unit 202 stores image data called a texture (hereinafter referred to as “first texture”) to be pasted on the surface of the model object 310. The texture storage unit 202 also stores a texture (hereinafter referred to as “second texture”) to be pasted on the surface of the plane object 320. The first texture and the second texture are stored in advance in, for example, a DVD-ROM, and the CPU 101 reads out the DVD-ROM loaded in the DVD-ROM drive 107 and temporarily stores it in the RAM 103. The CPU 101, the RAM 103, and the DVD-ROM drive 107 operate in cooperation to function as the texture storage unit 202. As will be described later, the first texture is also used as a texture to be pasted on the surface of the mirror image object 330.

  The mirror image calculation unit 203 calculates the position and shape of the mirror image object 330 based on the respective positions and shapes of the model object 310 and the plane object 320 stored in the position shape storage unit 201. The CPU 101, the image processing unit 108, and the RAM 103 work together to function as the mirror image calculation unit 203.

  More specifically, the mirror image calculation unit 203 determines the position of the point after conversion by coordinate conversion so that a certain point on the model object 310 (for example, the vertex of each polygon) is symmetric with respect to the plane object 320. Calculate and repeat this calculation for other points as well. Then, the points after the coordinate conversion are connected to form a polygon constituting the mirror image object 330, and the shape of the mirror image object 330 is determined. In short, the model object 310 is inverted with respect to the plane object 320, and the position and shape of the mirror image object 330 are calculated.

  FIG. 4A is an example in which the positional relationship among the model object 310, the plane object 320, and the mirror image object 330 is simplified. Here, it is assumed that the plane object 320 is a plane as shown in FIG. An intersection 402 between a plane object 320 and a straight line connecting a point 401 on the model object 310 and a corresponding point 403 on the mirror image object 330 coincides with the midpoint of the line connecting the point 401 and the point 403. In other words, distance R1 = distance R1 '. In this way, the model object 310 and the mirror image object 330 are in a plane-symmetrical relationship, and the mirror image calculation unit 203 calculates the position and shape of the mirror image object 330 so as to satisfy this relationship.

The shape of the plane object 320 is not limited to a plane.
FIG. 5A is another example in which the positional relationship among the model object 310, the plane object 320, and the mirror image object 330 is simplified. Here, the plane object 320 is a part of a cylinder including a plane whose center is a point 404 as shown in FIG. Point 401, point 402, point 403, and point 404 are on the same straight line. Also in this example, it can be said that the model object 310 and the mirror image object 330 are in a plane-symmetric relationship with each other using a convex mirror. The shape of the plane object 320 may be a plane, a cylinder (cylinder), a sphere, a concave surface, a convex surface, or a part or combination thereof.

  The transparency acquisition unit 204 determines the transparency of the first texture for each region according to the distance from the plane object 320 to each region (each polygon) constituting the surface of the mirror image object 330 calculated by the mirror image calculation unit 203. get. The transparency is a so-called α value. The CPU 101, the image processing unit 108, and the RAM 103 operate in cooperation to function as a transparency acquisition unit 204.

  FIG. 6 is an enlarged view of a part of the surface of the plane object 320 and the mirror image object 330. Like the model object 310, the mirror image object 330 is divided into minute polygons and converted into numerical data. The transparency acquisition unit 204 is a distance from the plane object 320 to each region 601 corresponding to each polygon (shown as regions 601-1, 601-2, and 601-3 in this drawing) (each in this drawing). L1, L2, L3) are calculated. Each region 601 of the mirror image object 330 is assigned a first texture fragment (part of a texture) by the generation unit 205 described later. The transparency acquisition unit 204 acquires the transparency of the assigned first texture fragment according to the calculated length of each distance. Typically, the transparency acquisition unit 204 calculates the transparency so that the transparency increases monotonously with respect to the calculated distance, and acquires the transparency of each region. Transparency should just be the tendency which increases monotonically as a whole, and may take a fixed value in a certain arbitrary distance area. For example, the transparency can be changed to give a predetermined number of gradations.

  As a result, as the image of the mirror image object 330 is closer to the plane object 320, the transparency becomes smaller and becomes a color closer to the original color of the first texture, and the mirror image object 330 is displayed more clearly as it is closer to the plane object 320. It will be. On the other hand, the transparency increases as the distance from the plane object 320 increases, and the mirror image object 330 is displayed so as to gradually melt into the background. Thus, by changing the α value, the mixing ratio of the background color and the texture color changes for each region.

For example, the transparency acquisition unit 204 changes the transparency of each region constituting the mirror image object 330 so as to satisfy the relationships as shown in FIGS. The vertical axis represents the transparency (α value) of each area constituting the mirror image object 330, and the horizontal axis represents the distance from each area to the plane object 3320. The transparency can take a value from 0 to 1. If the transparency is 0, it is completely opaque, and if the transparency is 1, it is completely transparent.
FIG. 7A is a graph showing an example of the transparency acquired by the transparency acquisition unit 204. In this example, the transparency increases linearly with distance. When the threshold distance D1 is reached, the transparency becomes a constant value (here, α = 1).
FIG. 7B is another example of the relationship between transparency and distance. In this example, the ratio of increasing transparency gradually increases. Or you may increase so that it may represent with a quadratic function, an exponential function, etc. Similarly, when the threshold distance D1 is reached, the transparency becomes a constant value. It should be noted that the ratio of increasing transparency may gradually decrease.
FIG. 7C shows another example of the relationship between transparency and distance. In this example, the ratio of increasing transparency gradually increases in the range where the distance is relatively short, and this ratio gradually decreases in the range where the distance is relatively long. Eventually the transparency converges to a certain value (here α = 1).
FIG. 7D is another example of the relationship between transparency and distance. In this example, the transparency changes discontinuously like a step function. If the number of steps is increased, the transparency appears to change smoothly.
These are merely examples, and it is needless to say that embodiments freely combined or deformed can be adopted. The transparency is changed in the range of 0 ≦ α ≦ 1, but may be changed in any other range αmin ≦ α ≦ αmax. αmin is not limited to zero, and αmax is not limited to one.

  The generation unit 205 obtains the projection destinations of the model object 310, the plane object 320, and the mirror image object 330 on the projection plane arranged in the virtual space. The CPU 101, the image processing unit 108, and the RAM 103 operate in cooperation to function as the generation unit 205.

  FIG. 8 is a schematic diagram illustrating how the generation unit 205 projects each object onto the projection plane 810. The projection plane 810 is disposed at an arbitrary location in the virtual space. The generation unit 205 projects an image of each object seen from the virtual viewpoint 820 arranged in the virtual space in the line-of-sight direction (the direction of the arrow Y1 in the figure) onto the projection plane 810. An image projected on the projection surface 810 becomes a display image output to a monitor connected to the image generation apparatus 200. For example, the projection destination of the point 851 on the model object 310 (the “hand tip” portion of the model object 310 in this figure) is the point 861 on the projection plane 810 (the same “tip of the hand” of the mirror image object 330 in the figure). Part). Similarly, the projection destination of the point 852 on the plane object 320 (the “tip of the stage” in the figure) is the point 862 on the projection plane 810 and the point 853 on the mirror image object 330 (the “tip of the head in the figure). The projection destination of “portion” corresponds to the point 863 on the projection plane 810, respectively. Similarly, the generation unit 205 calculates the projection destination for each of the other points of the model object 310, the plane object 320, and the mirror image object 330.

Then, the generation unit 205 generates image data for display by pasting the first texture or the second texture on the surface of each object and drawing (that is, texture mapping). More specifically, the generation unit 205
(1) First, a second texture is pasted on the projection target of the plane object 320,
(2) Next, a portion corresponding to each region of the first texture is pasted to the projection destination of each region of the mirror image object 330 with the transparency acquired by the transparency acquisition unit 204, respectively.
(3) Further, the first texture stored in the texture storage unit 202 (the transparency is not changed) is pasted on the projection destination of the model object 310,
Generate image data.

  For example, when the surface of the plane object 320 is made of a material that reflects light (creates reflection), the texture is pasted in the order of the plane object 320, the mirror image object 330, and the model object 310. If the surface of the plane object 320 is made of a material that hardly reflects light (does not create reflection), such as a ground of earth, for example, the mirror image object 330, the plane object 320, the model object 310, The texture should be pasted in the order.

  Here, the generation unit 205 may paste the texture using not the transparency acquired by the transparency acquisition unit 204 but the transparency acquired by other processing. For example, when there is a puddle on the ground, the first texture is pasted on the surface of the mirror image object 330 corresponding to the puddle portion with the transparency acquired by the transparency acquisition unit 204, and the mirror image corresponding to the other soil portion. The first texture may be pasted on the surface of the object 330 by making it completely opaque.

  If the entire mirror image object 330 is completely hidden behind the plane object 320 or another object when viewed from the viewpoint 820, the process of pasting the texture on the surface of the mirror image object 330 can be omitted.

  Next, the flow of image generation processing performed by each unit described above will be described with reference to the flowchart of FIG. In the following description, the image generation apparatus 200 generates an image including an object (for example, a player character object appearing in a game) arranged in a virtual space based on an instruction input from a user using the controller 105. I will explain the situation.

  First, the mirror image calculation unit 203 acquires data indicating the position and shape of the model object 310 and data indicating the position and shape of the plane object 320 from the position shape storage unit 201 (step S901).

  The mirror image calculation unit 203 obtains the position and shape of the mirror image object 330 from the acquired position and shape of the model object 310 and the position and shape of the plane object 320 (step S902). Data indicating the obtained position and shape is temporarily stored in the RAM 103.

  The transparency acquisition unit 204 obtains the distance from each area constituting the mirror image object 330 to the plane object 320 (step S903). For example, the transparency acquisition unit 204 draws a perpendicular line from the center point of each region corresponding to each polygon constituting the mirror image object 330 to the plane object, and the distance from the center point to the intersection of the perpendicular line and the plane object 320 (the length of the perpendicular line) ) Respectively. Typically, the center point of each region is the center of gravity. Data indicating the calculated distances is temporarily stored in the RAM 103.

  The transparency acquisition unit 204 acquires the transparency of the texture portion (the portion assigned to each region of the first texture) to be pasted to each region according to the distance calculated in step S903 (step S904). For example, in the range of 0 ≦ α ≦ 1, the transparency obtaining unit 204 obtains transparency with a larger α value as the calculated distance is longer and a smaller α value as the calculated distance is shorter.

  The transparency of the texture pasted on the surface of the mirror image object 330 is not the distance from the viewpoint 810 to the mirror image object 330 (each polygon constituting the object) but the distance from the plane object 320 to each mirror image object 330 (each polygon constituting the object). It depends on.

  The generation unit 205 arranges the projection plane 810 in this virtual space (step S905). The generation unit 205 determines the position of the projection plane 810 based on the position of the viewpoint 820, the direction of the line-of-sight vector (line-of-sight direction), and the zoom magnification. The user can use the controller 105 to instruct to change parameters for specifying the position of the virtual camera (viewpoint 810), the direction of the virtual camera (gaze direction Y1), the shooting magnification of the virtual camera, and the like. The unit 205 determines the position and orientation of the projection plane 810 based on the instruction input from the user.

  For example, the generation unit 205 arranges the projection plane 810 in a direction perpendicular to the line-of-sight vector starting from the viewpoint 810, and moves the projection plane 810 closer to the object to be imaged (zoom away from the viewpoint 810) when zooming in. And so on, when zooming out, the object is moved away from the object to be photographed (so as to approach the viewpoint 810). When changing the direction of the line-of-sight vector (that is, panning the virtual camera), the direction of the projection plane 810 is also changed according to the change in the direction of the line-of-sight direction.

  The generation unit 205 obtains a projection destination on the projection plane 810 arranged in step S905 for each of the model object 310, the plane object 320, and the mirror image object 330 (step S906). For example, the generation unit 205 perspectively projects each object on the projection plane 810. Thereby, each object arranged in the three-dimensional virtual space is projected on the two-dimensional virtual screen. In the present embodiment, since perspective projection is adopted as a projection method, an object far from the viewpoint 810 is small and an object near is projected large. However, parallel projection can be employed instead of perspective projection.

  The generation unit 205 reads the second texture, which is the texture for the plane object 320, stored in the texture storage unit 202, pastes the second texture on the projection destination of the plane object 320, and draws it (step S907).

  In addition, the generation unit 205 draws a portion of the first texture corresponding to each region in the projection destination region of the mirror image object 330 with the transparency acquired in step S904 (step S908).

  Further, the generation unit 205 reads the first texture, which is the texture for the model object 310, stored in the texture storage unit 202, pastes it on the projection destination of the model object 310, and draws it (step S909). Here, the generation unit 205 pastes the texture without changing the transparency.

  The image data generated in this way becomes image data to be displayed on the monitor. Since the generated image data includes the reflection (mirror image object 330) of the model object 310 on the floor surface (plane object 320), an image with a more stereoscopic effect and reality can be obtained. In addition, the higher the position from the floor, the more the image is reflected on the floor, so that the difference in height becomes easier to grasp.

  For example, when an image in which the model stands vertically on the stage is generated using the present invention, reflection on the stage near the foot of the model (portion close to the stage) is clear, but the viewpoint 810 is the model. Even if it is near, the reflection near the head (the part far from the stage) will gradually fade as if it was foggy, and instead the stage pattern will be clearly visible. In other words, the higher the position from the stage, the lighter the reflection on the stage becomes. If the transparency of the reflection near the head is greater than the transparency of the reflection near the foot, it is easy to see that the vicinity of the head is relatively higher from the stage than near the foot.

  If the transparency of each area constituting the mirror image object 330 is changed not according to the distance from the plane object 320 but according to the distance from the viewpoint 810, the transparency is changed so that "the farther the object looks dazzling". It will be. Therefore, if the viewpoint 810 is close to the model object 310 to about several meters, the transparency hardly changes. However, in the present embodiment, the transparency acquisition unit 204 changes the transparency of each region of the mirror image object 330 according to the distance from the plane object 320 instead of the distance from the viewpoint 810. That is, the transparency changes depending on the distance to the plane object 320 (height from the floor). Therefore, even when the viewpoint 810 is close to the model object 310, the mirror image object 330 becomes more transparent and thinner as the part is farther from the plane object 320, and the transparency becomes smaller and closer to the plane object 320. It becomes like this.

  If textures are pasted in order from an object far from the viewpoint 810 by simply using the Z buffer method or the Z sort method, the mirror image object 330 is usually farther from the plane object 320. The plane object 320 is overwritten on the object 330, and a mirror image is not displayed. However, in this embodiment, since the texture is pasted in the order of the plane object 320, the mirror image object 330, and the model object 310, the mirror image object 330 is not hidden by the plane object 320 and is not displayed.

  In addition to the model object 310, the plane object 320, and the mirror image object 330, for example, if there is another object such as a character object for background, the position and shape of the object are also calculated and a predetermined texture is pasted. Good. In that case, the earlier the order in which the texture is pasted, the more the object is pasted and disappears behind the texture pasted (becomes invisible from the viewpoint 810), so the process of pasting the texture is before step S907. , Before step S908, before step S909, or after step S909, depending on the scene. For example, if the object is a background object that is fixed far away from the model object 310, it is desirable that it be before step S907.

  In the present embodiment, the second texture is pasted on the plane object 320. However, when the plane object 320 is completely transparent, step S907 may be omitted. Further, for example, even if step S907 is omitted and the second texture is not pasted on the surface of the plane object 320, and as a result an image in which the plane object 320 is not displayed is generated, the mirror image object 330 is displayed together with the model object 310. Then, the user can be reminded that there is a stage that creates a reflection between the model object 310 and the mirror image object 330, and the load of the drawing process can be reduced.

  The present invention is not limited to the above-described embodiments, and various modifications and applications are possible. Moreover, it is also possible to freely combine the constituent elements of the above-described embodiments.

  The plane object 320 is not limited to a floor or a stage. For example, an image representing a ship floating on the water surface can be generated. In this case, the ship is the model object 310, the water surface is the surface object 320, and the hull image reflected on the water surface corresponds to the mirror image object 330. If the water surface is calm, the generation unit 205 generates an image by pasting textures in the order of the water surface, the hull image (shadow) reflected on the water surface, and the ship. That is, the generated image is an image as if the hull image is reflected on the water surface. If the water surface is in a rough state, the generation unit 205 generates an image by pasting textures in the order of the hull image reflected on the water surface, the water surface, and the ship. In other words, if it is calm, the hull image that should have been reflected on the surface of the water can be hidden.

  The plane object 320 is not limited to the one that spreads in the horizontal direction, such as a glossy floor, stage, water surface, sea surface, escape water, or the like. For example, it may be a mirror, a window, a side surface of a building covered with glass, etc. leaning in an arbitrary direction.

  In the above embodiment, the transparency acquisition unit 204 changes the transparency of the mirror image object 330 according to the distance from the plane object 320, not the distance from the viewpoint 820. However, the transparency may be changed according to the distance from the viewpoint 820 as well as the distance from the plane object 320. That is, the transparency acquisition unit 204 increases (a) the transparency of each area constituting the mirror image object 330 as the distance from each area to the plane object 320 increases, and (b) from each area to the viewpoint 820. You may make it enlarge, so that distance becomes long. In this way, it is possible to express a distant image as if it is far away, and the image becomes more realistic.

  A program for operating the image generating apparatus 200 as all or part of the apparatus is stored and distributed in a computer-readable recording medium such as a memory card, CD-ROM, DVD, or MO (Magneto Optical disk). May be installed in another computer and operated as the above-described means, or the above-described steps may be executed.

  Furthermore, the program may be stored in a disk device or the like included in a server device on the Internet, and may be downloaded onto a computer by being superimposed on a carrier wave, for example.

  As described above, according to the present invention, it is possible to provide an image generation apparatus, an image generation method, and a program suitable for expressing the reflection of an object while easily recognizing the position and shape of the object. Can do.

1 is a diagram illustrating a schematic configuration of a typical game device in which an image generation device of the present invention is realized. It is a figure for demonstrating the functional structure of an image generation apparatus. It is an example of the image produced | generated by an image generation apparatus. (A) It is a figure for demonstrating a model object, a plane object, and a mirror image object. (B) It is an example of a plane object. (A) It is a figure for demonstrating a model object, a plane object, and a mirror image object. (B) It is an example of a plane object. It is a figure for demonstrating the distance of a surface object and each area | region on a mirror image object. (A)-(d) is a figure which shows the example of the relationship between the transparency of each area | region on a mirror image object, and the distance from each area | region to a plane object. It is a figure for demonstrating the process which projects an image on a projection surface. It is a flowchart for demonstrating an image generation process.

Explanation of symbols

100 game device 101 CPU
102 ROM
103 RAM
104 Interface 105 Controller 106 External Memory 107 DVD-ROM Drive 108 Image Processing Unit 109 Audio Processing Unit 110 NIC
200 Image Generation Device 201 Position Shape Storage Unit 202 Texture Storage Unit 203 Mirror Image Calculation Unit 204 Transparency Acquisition Unit 205 Generation Unit 310 Model Object 320 Plane Object 330 Mirror Image Object 810 Projection Plane 820 Viewpoint

Claims (5)

A position shape storage unit for storing the position and shape of the model object arranged in the virtual space and the position and shape of the plane object;
A texture storage unit that stores a first texture to be pasted on the surface of the model object and a second texture to be pasted on the surface of the surface object ;
Mirror image calculation that calculates the position and shape of a mirror image object obtained by inverting the model object with respect to the plane object based on the position and shape of the model object and the plane object stored in the position shape storage unit And
Transparency of the first texture for each region according to each distance from the plane object stored in the position shape storage unit to each region constituting the surface of the mirror image object calculated by the mirror image calculation unit A transparency acquisition unit for acquiring
The projection destination of the model object and the mirror image object on the projection plane arranged in the virtual space is obtained, the second texture is pasted on the surface of the plane object, and then each region of the mirror image object A portion corresponding to each region of the first texture stored in the texture storage unit is pasted to the projection destination with the transparency acquired by the transparency acquisition unit, and then the projection of the model object is performed. A generation unit for pasting the first texture stored in the texture storage unit and generating an image;
An image generation apparatus comprising: The image generation apparatus according to claim 1,
The transparency acquisition unit increases the transparency as the distance from the surface object to the mirror image object increases.
An image generation apparatus characterized by that. The image generation apparatus according to claim 1,
The transparency acquisition unit monotonously increases the transparency with respect to the distance from the surface object to the mirror image object.
An image generation apparatus characterized by that. An image generation method executed by an image generation apparatus having a position shape storage unit, a texture storage unit, a mirror image calculation unit, a transparency acquisition unit, and a generation unit,
In the position shape storage unit, the position and shape of the model object arranged in the virtual space, and the position and shape of the plane object are stored,
The texture storage unit stores a first texture to be pasted on the surface of the model object and a second texture to be pasted on the surface of the plane object .
A position of a mirror image object obtained by inverting the model object with respect to the plane object based on the position and shape of the model object and the plane object stored in the position shape storage unit; A mirror image calculation step for calculating the shape;
In accordance with each distance from the plane object stored in the position shape storage unit to each region constituting the surface of the mirror image object calculated by the mirror image calculation step, the transparency acquisition unit A transparency acquisition step for acquiring the transparency of the texture;
The generation unit obtains a projection destination of the model object and the mirror image object with respect to a projection plane arranged in the virtual space, pastes the second texture on the surface of the plane object, and then the mirror image object the projection destination of each region, a portion corresponding to the respective regions of the first texture stored in the texture storage section, affixed respectively to the transparency acquired by the transparency acquisition step, then, the A step of pasting the first texture stored in the texture storage unit to the projection destination of the model object to generate an image;
An image generation method comprising: Computer
A position shape storage unit for storing the position and shape of the model object arranged in the virtual space, and the position and shape of the plane object;
A texture storage unit for storing a first texture to be pasted on the surface of the model object and a second texture to be pasted on the surface of the surface object ;
Mirror image calculation that calculates the position and shape of a mirror image object obtained by inverting the model object with respect to the plane object based on the position and shape of the model object and the plane object stored in the position shape storage unit Part,
Transparency for acquiring the transparency of the texture for each region according to each distance from the surface object stored in the position shape storage unit to each region constituting the surface of the mirror image object calculated by the calculation unit Acquisition department,
The projection destination of the model object and the mirror image object on the projection plane arranged in the virtual space is obtained, the second texture is pasted on the surface of the plane object, and then each region of the mirror image object A portion corresponding to each region of the first texture stored in the texture storage unit is pasted to the projection destination with the transparency acquired by the transparency acquisition unit, and then the projection destination of the model object A generating unit that pastes the first texture stored in the texture storage unit to generate an image;
A program characterized by functioning as

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