JP2010191607A - Method and device for generating and displaying image, server device, and image display terminal - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To allow even an image display terminal of low processing power to display a scenery in a three-dimensional space, which is viewed from a moving visual point, in reality. <P>SOLUTION: When receiving information including the position of a visual point from a display terminal device 4, a server device 2 divides a space ahead of a visual point into a plurality of blocks based on a distance from the visual point, and extracts information belonging to each block from three-dimensional space information 31, and generates blocked three-dimensional space information 32 (three-dimensional space information blocking processing 22), and generates a two-dimensional photographic image 33 to be projected on a screen virtually installed in a boundary at the opposite side of the visual point based on the blocked three-dimensional space information 32 of each block (two-dimensional projection image generation processing part 23), and transmits it to the display terminal device 4. The display terminal device 4 generates a superimposed image by overlapping the received two-dimensional projective images 51 of each block in the order of the far distance from the visual point, and displays it on a display device 70 (two-dimensional projection image superimposed display processing part 44). <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an image generation display system, an image generation display method, a server device, and an image display for displaying a landscape in a three-dimensional space that can be seen from a moving viewpoint in a predetermined three-dimensional space on a two-dimensional display screen. Regarding terminals.

  In recent years, a car navigation apparatus can perform a three-dimensional display of a city area, a bird's-eye view map display, or the like in accordance with the position and traveling speed of a vehicle. In addition, a personal computer connected to the Internet can display a three-dimensional bird's-eye image of a city area or a sightseeing spot viewed from a moving viewpoint in real time according to the movement of the viewpoint.

  Generally, information that determines the arrangement and shape of an object within a predetermined three-dimensional space (for example, three-dimensional terrain information such as mountains, rivers, and coasts represented by contour lines, three-dimensional shape information such as buildings) When stored in the server device, a display image (for example, a bird's eye view) of a landscape seen from a moving viewpoint (for example, a window of a vehicle, an aircraft, etc.) included in the three-dimensional space is networked to the server device. The following methods (1) to (3) are conceivable for displaying a realistic motion on an image display terminal connected via the network.

(1) The information (hereinafter referred to as “three-dimensional space information”) that determines the arrangement and shape of an object within the three-dimensional space to be displayed is transmitted to an image display terminal (such as a personal computer or a navigation device). The image display terminal itself generates and displays a display image that changes as the viewpoint moves one frame at a time.
(2) The server apparatus generates a continuous walk-through image in advance, and the image display terminal transmits and displays the walk-through image.
(3) The server device generates and displays a display image for each frame accompanying the movement of the viewpoint in real time, and the image display terminal displays the distributed display image as it is.

  For example, in the car navigation device described in Patent Document 1, the method (1) is adopted, but in this case, since the amount of information of the transmitted three-dimensional spatial information becomes large, it is necessary for the image display terminal. The storage capacity for storing the three-dimensional spatial information becomes a burden. In addition, a dedicated program for generating a display image from the three-dimensional space information needs to be installed in advance in the image display terminal, and the display image generation processing is a heavy burden on the image display terminal. .

  In the method (2), since the image display terminal does not need to generate a display image from the three-dimensional space information, the processing load on the image display terminal is small, but a display other than the display image generated in advance is displayed. The image cannot be displayed. Therefore, in this case, the image display terminal can display only a display image from a viewpoint that moves along a predetermined route.

  Further, when the method (3) is used, the image display terminal can display a display image from an arbitrary viewpoint on a general web browser without a dedicated program for generating a display image. Is possible. On the other hand, since the server device needs to generate and distribute a display image such as a bird's eye view for each frame in accordance with the movement of the viewpoint position, the processing amount and the amount of information to be distributed increase. . In particular, when generating a 3D bird's-eye view of a large screen for each frame, or when performing precise rendering in consideration of light reflection and flare effects on the display image of each frame, the processing load on the server device is It will be even bigger.

  In Patent Document 2, as a method for reducing the processing load on the server device and the image display terminal, the server device has three-dimensional space information on a limited range of a predetermined distance range from the user (viewpoint) position and the background of the information. The two-dimensional image is downloaded to the image display terminal, and the image display terminal uses the limited three-dimensional space information and the background two-dimensional image to display a real three-dimensional space display image. A technique for generating is disclosed.

  In this case, as long as the viewpoint is in the center of the limited space, the server device does not need to newly download the three-dimensional space information and the background two-dimensional image to the image display terminal. When moving to the peripheral part of the space, new three-dimensional space information whose viewpoint is located at the center and the two-dimensional image of the background may be downloaded. Accordingly, the processing load on the server device is reduced, and the amount of information distributed to the image display terminal is also reduced. Furthermore, the image display terminal only needs to generate a display image using a limited range of three-dimensional spatial information and a background two-dimensional image, so that the processing load is reduced.

JP 2007-279067 A Japanese Patent Application No. 10-31471

  However, in the case of the invention described in Patent Document 2, the image display terminal requires a dedicated program for generating and displaying a display image from the three-dimensional space information, and the execution of the program requires a corresponding processing load. It is necessary to bear. In addition, since a dedicated program is required, a web browser normally installed on a low-priced image display terminal with low processing capability cannot display a display image that changes as the viewpoint moves in real. .

  An object of the present invention is to display a display image of a landscape in a three-dimensional space that can be viewed from a moving viewpoint in the three-dimensional space even if the image display terminal has a low processing capability and does not have a dedicated display image generation program. An object of the present invention is to provide an image generation and display method, an image generation and display system, a server device, and an image display terminal that can display more realistically.

  The image generation and display system of the present invention inputs a server device that holds three-dimensional space information representing a shape of a predetermined three-dimensional space, and position information of a viewpoint in the three-dimensional space, and is visible from the viewpoint And a display terminal device that displays a landscape in a three-dimensional space. Then, when the server device receives information including the position of the viewpoint in the three-dimensional space from the display terminal device, the server device divides the space ahead of the viewpoint into a plurality of blocks according to the distance from the viewpoint, Blocked three-dimensional spatial information belonging to each block is generated from the three-dimensional spatial information, a virtual screen is set on the boundary opposite to the viewpoint of the block, and the blocked three-dimensional spatial information of the block Is used to generate a two-dimensional projection image projected onto the screen by the line of sight from the viewpoint, and the generated two-dimensional projection image is transmitted to the display terminal device. On the other hand, the display terminal device receives the two-dimensional projection image transmitted from the server device, and superimposes the two-dimensional projection image corresponding to each block so that the image of the block far from the viewpoint is in the back. In addition, a superimposed image is generated, and the generated superimposed image is displayed on the display device.

  In the present invention, a predetermined three-dimensional space is divided into a plurality of blocks according to the position of the viewpoint, and a two-dimensional projection image is generated from the three-dimensional space information belonging to each block. Processing with a large processing load is performed by the server device. Therefore, the display terminal device only has to perform the process of superimposing the two-dimensional projection image of a plurality of blocks according to the viewpoint position by appropriately moving the image to the left, right, up, and down, enlarging or reducing it. The processing load on the terminal device can be small.

  According to the present invention, even in an image display terminal with a low processing capability that does not have a dedicated display image generation program, a display image of a landscape in the three-dimensional space that can be seen from a moving viewpoint in the three-dimensional space. It becomes possible to display more realistically.

The figure which showed the example of the structure of the image production | generation display system which concerns on embodiment of this invention. The figure for demonstrating the content of the process performed in the server apparatus which concerns on embodiment of this invention. The figure for demonstrating the content of the process performed in the display terminal device which concerns on embodiment of this invention. The figure which showed the example of the movement path | route of a screen and a viewpoint, in order to produce | generate a two-dimensional projection image in a server apparatus. The figure which showed the example of the superimposed image obtained by superimposing each screen image. The figure which showed the example of the display image in case a viewpoint position is "position: A" and "position: B". The figure which showed the example of the display image in case a viewpoint position is "position: C" and "position: D". The figure for demonstrating the relationship between the magnitude | size of a two-dimensional projection image display screen, and the timing which a display terminal device requests the production | generation of a two-dimensional projection image to a server apparatus. The figure which showed the example of the screen buffer which considered the viewpoint moved to right and left. The figure which showed the example of the screen buffer which considered the viewpoint which moves back and forth. The figure for demonstrating the example of a projection image generation in case a viewpoint rotates in the same position. The figure which showed the example which supplements the blocking process of three-dimensional spatial information. The figure which showed the modification of the structure of the image production | generation display system which concerns on embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  Initially, with reference to FIG. 1, the example of a structure of the image generation display system which concerns on embodiment of this invention is demonstrated. As shown in FIG. 1, the image generation display system 1 is configured by connecting a plurality of display terminal devices 4 to a server device 2 via a communication network 3.

  The server device 2 is configured by a computer having a high processing capability including at least an arithmetic processing unit 20 and a storage unit 30, and the storage unit 30 stores the arrangement and shape of objects in a predetermined three-dimensional space. Three-dimensional spatial information 31 (for example, elevation map data represented by contour line data, etc.), which is described information, is held. The arithmetic processing unit 20 includes a two-dimensional projection image generation request reception processing unit 21, a three-dimensional spatial information blocking processing unit 22, a two-dimensional projection image generation processing unit 23, and a two-dimensional projection image transmission processing unit 24. Composed.

  That is, the arithmetic processing unit 20 receives the two-dimensional projection image generation request information transmitted from the display terminal device 4 via the communication network 3 (two-dimensional projection image generation request reception processing unit 21), and receives the received two-dimensional Based on the projection image generation request information, a plurality of blocked three-dimensional space information 32 is generated from the three-dimensional space information 31 (three-dimensional space information blocking unit 22), and each of the plurality of blocked three-dimensional space information 32 is generated. A two-dimensional projection image 33 is generated (two-dimensional projection image generation processing unit 23), and the generated two-dimensional projection images 33 are transmitted to the display terminal device 4 via the communication network 3 (two-dimensional projection image transmission). Processing unit 24).

  The processing by the three-dimensional spatial information blocking processing unit 22 and the two-dimensional projection image generation processing unit 23 and specific examples of the blocked three-dimensional spatial information 32 and the two-dimensional projection image 33 will be described separately with reference to FIG. explain in detail.

  On the other hand, the display terminal device 4 is configured by a personal computer including the arithmetic processing unit 40, the storage unit 50, the input device 60, the display device 70, and the like, and the processing performance is not necessarily high. The arithmetic processing unit 40 includes a viewpoint position & gazing point position acquisition unit 41, a two-dimensional projection image generation request transmission processing unit 42, a two-dimensional projection image reception processing unit 43, and a two-dimensional projection image superimposed display processing unit 44. Consists of.

  That is, the arithmetic processing unit 40 acquires the viewpoint position and the coordinate position information of the gazing point position input from the input device 60 by the user or the like (view point position & gazing point position acquisition processing unit 41), and the acquired viewpoint position and The two-dimensional projection image generation request information attached with the coordinate position information of the gazing point is transmitted to the server device 2 via the communication network 3 (two-dimensional projection image generation request transmission processing unit 42). In addition, the arithmetic processing unit 40 receives a plurality of two-dimensional projection images transmitted from the server device 2 via the communication network 3 according to the two-dimensional projection image generation request information, and performs two-dimensional projection on the storage unit 50. This is stored as an image 51 (two-dimensional projection image reception processing unit 43), and the plurality of two-dimensional projection images 51 are appropriately enlarged, reduced, and moved, and superimposed on the display device 70 (two-dimensional projection image superimposition). Display processor 44).

  A specific example of the processing of the two-dimensional projection image superimposing display processing unit 44 will be described in detail separately with reference to FIG.

  In FIG. 1, the communication network 3 is assumed to be the Internet here, but may be a LAN (Local Aria Network) or a WAN (Wide Aria Network) with a limited communication range. At this time, the server device 2 functions as a so-called WEB server, and the display terminal device 4 includes a WEB browser.

  Next, processing executed in the server device 2 will be described in detail with reference to FIG. Here, FIG. 2A is a diagram illustrating an example of a processing flow of processing executed by the arithmetic processing unit 20 of the server device 2, and FIG. 2B is a specific example of two-dimensional projection image generation processing. FIG. Here, an example of generating a two-dimensional projection image for displaying a bird's eye view from altitude map data is shown.

  The arithmetic processing unit 20 of the server device 2 first executes a two-dimensional projection image generation request reception process (step S11). That is, the arithmetic processing unit 20 receives the two-dimensional projection image generation request information transmitted from the display terminal device 4. Here, the 2D projection image generation request information is command information for the display terminal device 4 to request the server device 2 to generate a 2D projection image, and the information is described by the 3D space information 31. Position information of a viewpoint 8 and a gazing point (not shown) set in a space (hereinafter referred to as the space).

  Next, the arithmetic processing unit 20 executes a three-dimensional spatial information blocking process (step S12). That is, the arithmetic processing unit 20 extracts the position information of the viewpoint 8 and the gazing point from the received two-dimensional projection image generation request information, and determines the line of sight based on the viewpoint 8 and the gazing point. The line of sight is expressed as a vector from the viewpoint 8 toward the gazing point. Next, the arithmetic processing unit 20 divides the space in front of the viewpoint 8 in the space (the direction of the line of sight) for each predetermined distance, and generates a plurality of blocks.

  The lower half of FIG. 2B shows a state in which the space in front of the viewpoint 8 is blocked into a short distance block, a medium distance block, a long distance block, and a background block. Further, in FIG. 2B, the space (the space described by the three-dimensional space information 31) is represented as a map on which the contour lines 9 are drawn, and the boundaries of the spaces that are blocked in each space are It is represented as a thick solid line drawn on the map.

  That is, in the lower half of FIG. 2B, the three-dimensional spatial information 31 in front of the viewpoint 8 is blocked into short-distance block data 321, medium-distance block data 322, long-distance block data 323, and background block data 324. The three-dimensional spatial information 31 of each block that has been blocked is collectively referred to as the blocked three-dimensional spatial information 32.

  At this time, the number of blocks for blocking the space in front of the viewpoint 8 is four blocks here, but is not limited to four blocks. In principle, the background block continues to the point of infinity along the line-of-sight direction, but may be a finite distance as appropriate. Further, the horizontal width and vertical width of each block are appropriately determined based on the size of the screen described below. Adjacent blocks may include the same space overlapping each other.

  In addition, the blocked three-dimensional spatial information 32 of each block obtained in this way is temporarily held in the storage unit 30.

  Next, the arithmetic processing unit 20 executes a two-dimensional projection image generation process (step S13). In other words, the arithmetic processing unit 20 sets a virtual screen at the boundary opposite to the viewpoint 8 of each block obtained by blocking the space in the process of step S12, and blocks each block from the viewpoint 8 into a blocked three-dimensional space. A process of projecting a landscape seen through the spatial shape described by the information 32 onto each screen is executed.

  Each screen set at this time is a plane substantially perpendicular to the line of sight from the viewpoint 8, and the two-dimensional projection image generation processing has the following characteristics.

  First, the two-dimensional projection image 33 projected on each screen is independently generated using only the blocked three-dimensional space information 32 of the corresponding block. That is, in this process, the arithmetic processing unit 20 generates a short-distance screen image 331 to be projected on the short-distance screen using only the short-distance block data 321 and uses only the medium-distance block data 322 for the medium-distance screen. A projected mid-range screen image 332 is generated, a long-range screen image 333 is generated that is projected onto the long-range screen using only the long-range block data 323, and is projected onto the background screen using only the background block data 324. A background screen image 334 is generated.

  Secondly, the size of the screen for projecting each two-dimensional projection image 33 can be set independently. As will be described later, normally, the screen farther from the viewpoint 8 is made larger. By doing so, it is possible to reduce the amount of data and the number of transmissions of the two-dimensional projection image 33 to be transmitted to the display terminal device 4.

  Third, the display accuracy (number of pixels of the display image) of each two-dimensional projection image 33 can be set independently. Normally, the two-dimensional projection image 33 closer to the viewpoint 8 such as the short-range screen image 331 is set with higher display accuracy, and the two-dimensional projection image 33 farther from the viewpoint 8 such as the background screen image 334 is set with lower display accuracy. . By doing so, the data amount of the two-dimensional projection image 33 transmitted from the server device 2 to the display terminal device 4 can be reduced.

  Fourth, the background portions of the short-range screen image 331, the medium-range screen image 332, and the long-range screen image 333 are assumed to be transparent, and the background portion of the background screen image 334 is assumed to be opaque. By doing so, the display terminal device 4 can easily superimpose a plurality of screen images 331 to 334.

  The two-dimensional projection image 33 projected on each screen generated as described above is temporarily held in the storage unit 30.

  Next, the arithmetic processing unit 20 executes a two-dimensional projection image transmission process (step S14). That is, the arithmetic processing unit 20 transmits the two-dimensional projection image 33 generated by the above process to the display terminal device 4 via the communication network 3.

  Next, the process executed in the display terminal device 4 will be described in detail with reference to FIG. Here, FIG. 3A is a diagram illustrating an example of a processing flow of processing executed by the arithmetic processing unit 40 of the display terminal device 4, and FIG. 3B is a schematic diagram of superimposing processing of a two-dimensional projection image. FIG.

  As shown in FIG. 3A, the arithmetic processing unit 40 of the display terminal device 4 first executes viewpoint position & gazing point position acquisition processing (step S21). That is, the arithmetic processing unit 40 acquires the viewpoint position and the gazing point position that are appropriately input via the input device 60 such as a keyboard, a mouse, a tablet, or a joystick. Then, the arithmetic processing unit 40 determines whether or not a new two-dimensional projection image 51 needs to be acquired for the acquired viewpoint position and gazing point position (step S22). The criteria for the determination will be described separately with reference to the drawings.

  If it is determined in step S22 that a new two-dimensional projection image 51 needs to be acquired (Yes in step S22), the arithmetic processing unit 40 executes a two-dimensional projection image generation request transmission process (step S23). Then, the server apparatus 2 is transmitted with 2D projection image generation request information, and the server apparatus 2 is requested to generate a 2D projection image. At this time, the information on the viewpoint position and the point of gaze position is included in the two-dimensional projection image generation request information.

  Next, the arithmetic processing unit 40 enters a state of waiting for reception of the two-dimensional projection image 33 newly generated by the server device 2 and transmitted from the server device 2 (step S24). Then, when the two-dimensional projection image 33 is transmitted from the server device 2, a two-dimensional projection image reception process for receiving it is executed (step S25). The received two-dimensional projection image 33 is held in the storage unit 50 as the two-dimensional projection image 51 in the display terminal device 4.

  Next, the arithmetic processing unit 40 executes a two-dimensional projection image superimposed display process using the two-dimensional projection image 51 held in the storage unit 50 (step S26). Here, as shown in FIG. 3B, the superimposing process of the two-dimensional projection image is performed by arranging a background screen image 514 on the lower side (in the back) and a long-distance screen image 513 on the front side (on the front side). This is a process of generating a composite image in which the middle-range screen image 512 and the short-range screen image 511 are sequentially superimposed. At this time, background portions other than the background screen image 514 are made transparent and overlapped. The arithmetic processing unit 40 displays the image generated by superimposing as described above on the display device 70.

  In addition, when it is determined in step S22 that acquisition of a new two-dimensional projection image 51 is not necessary (No in step S22), the arithmetic processing unit 40 transmits the two-dimensional projection image generation request information to the server device 2. Without using the two-dimensional projection image 51 held in the storage unit 50 until then, a two-dimensional projection image superimposed display process is executed (step S26).

  Next, the arithmetic processing unit 40 returns to step S <b> 21, executes viewpoint position & gazing point position acquisition processing, and acquires a new viewpoint position and gazing point position input via the input device 60. That is, the arithmetic processing unit 40 displays the scenery in the space seen from the viewpoint 8 that changes following the moving viewpoint position and the gazing point position by repeatedly executing the processes of Steps S21 to S26. 70 can be displayed.

  As described above, in this embodiment, the arithmetic processing unit 40 generates an image that can be seen from the viewpoint 8 only by superimposing the two-dimensional projection images 51 of a plurality of screens, if possible. Then, in order to make the image seen from the viewpoint 8, that is, the image displayed on the display device 70 look more realistically close to the movement of the stereoscopic image, the superimposition processing of the two-dimensional projection image 51 is as follows. Are devised.

  That is, the screen images 511 to 514 can be independently moved left and right and up and down, and enlarged or reduced in accordance with the movement of the viewpoint 8. For example, when the viewpoint 8 moves in the horizontal and vertical directions, as the viewpoint 8 moves, the screen images 511 to 514 are moved larger as the screen image is closer to the viewpoint 8, and smaller as the screen image is farther away. Move. Further, when the viewpoint 8 moves forward or backward along the line-of-sight direction, the screen image closer to the viewpoint 8 is enlarged or reduced with a larger change, and the screen image far from the viewpoint 8 is enlarged or reduced only slightly. I will not let you.

  By superimposing the two-dimensional projection image 51 as described above, the image displayed on the display device 70 has a realistic stereoscopic effect and perspective.

  Subsequently, a specific example of a display image obtained by superimposing the two-dimensional projection image 51 will be described with reference to FIGS.

  In FIG. 4, the map on which the contour line 9 is drawn represents certain three-dimensional space information 31, and the three-dimensional space information 31 includes a short-distance screen 341 a, a medium-distance screen 342 a, a medium-distance screen 342 b, a long-distance screen 343 a and The background screen 344a is divided into short distance block data 321a, medium distance block data 322a, medium / long distance block data 322b, long distance block data 323a and background block data 324a. Unlike the case of FIG. 2 (4 blocks), the number of blocks is 5 blocks.

  The screens 341a to 344a have screen images (two-dimensional projection image 33) of “image: 1”, “image: 2”, “image: 3”, “image: 4”, and “image: background”, respectively. Is projected.

  Here, FIG. 5A shows an example of each screen image (however, only “image: 1” and “image: 4” are displayed in the figure). FIG. 5B is an example of a superimposed image in which each screen image is superimposed on the display terminal device 4. At this time, the background portions of “image: 1” to “image: 4” are transparent, and when these images are generated by the server device 2, the background portion is set to a transparent color (for example, blue). Has been.

  In the superimposed display on the display terminal device 4, the background portion of each screen image is made transparent. As a result, the image displayed on the display device 70 is far from the viewpoint 8 as shown in FIG. The screen images are sequentially arranged on the back side, and they appear to overlap in a three-dimensional manner.

  Therefore, when the user operates the input device 60 such as a mouse, the position of the viewpoint 8 is changed to “position: A”, “position: B”, “position: C”, “ When it is moved diagonally forward to “position: D”, the display range 35 is also moved according to the viewpoint position, and as a result, the images displayed on the display device 70 are also shown in FIGS. It changes like the images shown in (b), FIG. 7 (a) and FIG. 7 (b).

  As can be seen from FIGS. 6 and 7, as the viewpoint 8 moves to the right, the screen image close to the viewpoint 8 quickly moves to the left, while the screen image far from the viewpoint 8 moves slowly to the left. . In addition, when the viewpoint 8 approaches, in particular, it can be seen that “image: 1” on the short-distance screen is rapidly enlarged and displayed. When such display is performed in real time along with the movement of the viewpoint 8, the user can feel as if he / she is actually moving in the virtual space.

  Note that such a superimposed display of the screen image is performed in the display terminal device 4, but the display process does not require the 3D space information 31, and a 2D projection image is obtained from the 3D space information 31. There is no need for a program to generate. The display terminal device 4 can superimpose and display these screen images by a normal WEB browser normally installed in a general personal computer used by an individual.

  Subsequently, referring to FIGS. 8 to 10, the timing for transmitting and receiving the two-dimensional projection image 33 between the server device 2 and the display terminal device 4, and the method for switching the two-dimensional projection image 33 accompanying the movement of the viewpoint 8. Etc. will be explained.

  As described above (see FIG. 3), the arithmetic processing unit 20 of the display terminal device 4 executes the two-dimensional projection image generation request transmission process when the two-dimensional projection image 51 is required (Yes in step S22). (Step S23), the server apparatus 2 is requested to generate and transmit a new two-dimensional projection image 33.

  Here, “when the two-dimensional projection image 51 is needed” means that a superimposed image can be generated in the two-dimensional projection image 51 held in the storage unit 50 until then by the movement of the viewpoint position or the gazing point position. When it is gone. Specifically, it means a case where the two-dimensional projection image 51 (each screen image) held in the storage unit 50 does not fit in the visual field of the viewpoint 8, that is, the display range 35.

  In the present embodiment, the server device 2 considers the moving direction of the viewpoint 8 and the like, for example, as shown in FIG. 8, each screen 341-1 for generating a two-dimensional projection image 33 (each screen image). The size of 344 is made wider than the display range 35. Then, even if the viewpoint 8 moves a little, the display range 35 does not deviate from the screens 341 to 344, so the display terminal device 4 renews the server device 2 every time the viewpoint 8 moves. It is no longer necessary to obtain a two-dimensional projection image 33. Therefore, the server device 2 can reduce the transmission frequency of the two-dimensional projection image 33 (see FIG. 2) to the display terminal device 4. As a result, the processing load on the server device 2 is also reduced, and the load on the communication amount for the communication network 3 is also reduced.

  Further, as shown in FIG. 8, consider a case where the size of the background screen 344 and the long-distance screen 343 is made larger than the size of the short-distance screen 341. For example, when the viewpoint 8 moves from “position: A” to “position: B”, the short distance screen 341 falls outside the display range 35. On the other hand, the middle range screen 342, the long range screen 343, and the background screen 344 are included in the display range 35.

  In such a case, the display terminal device 4 does not request the server device 2 to generate all screen images, but requests only the short-range screen images to be generated. In response to the request, the server apparatus 2 sets new short-distance block data 321C and a new short-distance screen 341C, and displays only the short-distance screen image projected on the short-distance screen 341C as the two-dimensional projection image 33. It transmits to the terminal device 4.

  Accordingly, the server device 2 only needs to generate and transmit the two-dimensional projection image 33 for the limited screen to the display terminal device 4, so that the processing load is reduced and the amount of communication with the communication network 3 is reduced. The load is also reduced.

  As described above, when the display terminal device 4 needs the two-dimensional projection image 51, the display terminal device 4 requests the server device 2 to generate and transmit the two-dimensional projection image 51, and 2 transmitted from the server device 2 in response to the request. A superimposed image to be displayed on the display device 70 is generated using the three-dimensional projection image 51. At this time, if a delay more than necessary occurs in the transmission of the two-dimensional projection image 33 from the server device 2 due to processing in the server device 2 or communication delay in the communication network 3, each frame in the server device 2 is transmitted. A delay occurs in the display, and the realistic sensation of the scenery in the space moved and displayed together with the viewpoint 8 is remarkably impaired.

  Therefore, in this embodiment, the concept of a screen buffer is introduced. The screen buffer is a new screen that is provided adjacent to the screen that is set at that time and that is provided by predicting the destination to which the viewpoint 8 moves. For example, as illustrated in FIG. 9, when the viewpoint 8 moves rightward from “position: A” to “position: B”, the server device 2 displays the near-field screen 341 in use at that time. Adjacent to this, a short-distance screen buffer 341B provided for the right movement of the viewpoint 8 is provided.

  That is, when the server apparatus 2 generates a short-distance screen image projected on the short-distance screen 341 using the short-distance block data 321, the display range 35 is displayed in the short-distance screen 341 at the same time or thereafter. A short distance screen buffer image projected onto the short distance screen buffer 341B is generated by using the short distance block data 321B prepared for the right movement of the viewpoint 8 just before deviating from the range. Then, the short-range screen buffer image generated in this way is transmitted to the display terminal device 4.

  Therefore, the display terminal device 4 can quickly generate a superimposed image to be displayed on the display device 70 using the short-distance screen buffer image even if the display range is out of the short-distance screen 341. That is, it is possible to prevent display delay caused by processing delay in the server device 2, communication delay in the communication network 3, and the like.

  In addition, when a screen buffer is provided, if an overlapping portion of the overlapping block data 321D is provided between the short-distance block data 321 and the short-distance block data 321B prepared for the right movement of the viewpoint 8, 2 When switching between two-dimensional projection images, display gaps and discontinuous display that tend to occur at the joints of the images can be made inconspicuous, and the discomfort of the display image felt by the user can be alleviated or eliminated. it can.

  Note that the concept of the screen buffer can be applied not only to the short distance screen 341 but also to other screens such as the intermediate distance screen 342.

  Further, the concept of the screen buffer can be applied to the viewpoint 8 that moves back and forth. FIG. 10 shows an example of the short-distance screen buffer 341 </ b> F prepared for the advance of the viewpoint 8 with respect to the short-distance screen 341. That is, the server device 2 provides a short-distance screen buffer 341 </ b> F when the viewpoint 8 moves forward, generates a short-distance screen buffer image for the short-distance screen buffer 341 </ b> F, and transmits it to the display terminal device 4. However, in this case, the short distance screen buffer 341 </ b> F is not provided when the short distance screen 341 is out of the display range 35.

  In general, when the viewpoint 8 moves forward, the size of the short-range screen image increases rapidly, and the display image becomes gradually coarser. Therefore, when the size of the short-distance screen image currently used for the superimposed display or the roughness of the image becomes a predetermined size or roughness, the display terminal device 4 displays the screen image used for the superimposed display. , Switch to the short-distance screen buffer image sent in advance. By doing in this way, it can prevent that the display image of a short distance screen image becomes coarse especially.

  In this case, the short-distance block data 321F provided for the short-distance screen buffer 341F has overlapping block data 321E with the intermediate-distance block data 322 for the intermediate-distance screen 342. Is preferred. By doing so, it becomes possible to more realistically represent the change in the image at the boundary between the short-distance screen image and the medium-distance screen image as the viewpoint 8 advances.

  Next, with reference to FIG. 11, generation of a projection image when the viewpoint 8 rotates at the same position will be described. When the viewpoint 8 rotates, the position of the gazing point 80 changes abruptly. Therefore, assuming an extreme case, it is necessary to prepare a viewpoint rotation screen buffer 34K that covers all 360 degrees around the viewpoint 8. There is. In that case, the server apparatus 2 becomes a heavy processing burden just by generating the buffer screen image.

  By the way, when the viewpoint 8 rotates, the screen image changes greatly, so that it appears to the user as a flowing image. Therefore, when the viewpoint 8 is rotating, it is not always necessary to display the screen image with high accuracy.

  Therefore, in this embodiment, the server device 2 is provided with at least one viewpoint rotation screen buffer 34K adjacent to the projected image screen 34M being displayed when the viewpoint 8 is stationary or moving slowly, and the viewpoint A screen image based on the rotation screen buffer 34K is generated and transmitted to the display terminal device 4. In FIG. 11A, the viewpoint rotation screen buffer 34 </ b> K is provided on the entire circumference of the viewpoint 8, but is not necessarily provided over the entire circumference. At this time, the image projected onto the projection image screen 34M is a precise image having a number of pixels of, for example, 1280 pixels × 1024 pixels. On the other hand, the image projected onto the viewpoint rotation screen buffer 34K is a rough image obtained by projecting an image having a pixel number of, for example, 128 pixels × 102 pixels onto a screen having the same size as the projection image screen 34M. It is an image.

  When the viewpoint 8 is rotated at a speed equal to or higher than a predetermined rotation speed, the display terminal device 4 uses the image of the coarse image viewpoint rotation screen buffer 34K to superimpose to be displayed on the display device 70. Generate an image. At this time, the superimposed image of the coarse image does not necessarily require a realistic stereoscopic effect, so the number of blocks for blocking the three-dimensional spatial information 31 is reduced, for example, a medium-range screen image and a background screen image A superimposed image may be generated only by using the above.

  In addition, after the viewpoint 8 rotates at a speed equal to or higher than a predetermined rotation speed, when the rotation speed falls below a predetermined speed at a certain speed, the display terminal device 4 is shown in FIG. As described above, the coarse image displayed at that time is switched to the fine image projected on the new projection image screen 34N at the same position as the screen on which the coarse image was generated. However, in this case, since it is necessary to request the server apparatus 2 to generate the precision image (two-dimensional projection image 33), the request is made early considering the processing delay and the like.

  As described above, since the superimposed image is displayed using the coarse image, the processing load on the server device 2 can be reduced, and the amount of information transmitted from the server device 2 to the display terminal device 4 can be reduced. Therefore, the communication load on the communication network 3 can be reduced.

  The display terminal device 4 may leave the precision image data of the projected image screen 34M that was initially displayed in the storage unit 50. In particular, when the amount of rotation of the viewpoint 8 is small, it is often unnecessary to generate a projection image on the long-distance screen or the background screen. Therefore, the processing amount of the server device 2 is reduced and the communication load of the communication network 3 is reduced. The effect of leaving is great.

  As described above, according to the embodiment of the present invention, the display terminal device 4 uses only the two-dimensional projection image 51 to display the scenery in the three-dimensional space that can be seen from the moving viewpoint 8 in the predetermined three-dimensional space. Images can be displayed realistically. Moreover, the processing content can be easily realized by a WEB browser installed in a normal personal computer. Therefore, the present embodiment can be applied to a general personal computer with not so high performance. Can be easily applied.

  Then, with reference to FIG. 12, it supplements about the blocking process of the three-dimensional space information 31. FIG. In the present embodiment, the block processing of the three-dimensional space information 31 is not performed for all the predetermined three-dimensional spaces in advance, and the three-dimensional space information is moved in the vicinity of the viewpoint position as the viewpoint position is moved. A block for blocking 31 is generated.

  For example, as illustrated in FIG. 12, when the viewpoint 8 is at “position: A”, the server device 2 determines the short-distance block data 321,..., According to the viewpoint position and the point of sight (not shown). Each block defined by the long-distance block data 323,... Is set. Similarly, when the viewpoint 8 moves to “position: B”, new short-distance block data 321N,..., New long-distance block are similarly generated according to the viewpoint position and the gazing point (not shown). Each block defined by the data 323N,... Is set.

  At this time, each piece of block data that becomes unnecessary as the viewpoint 8 moves may be deleted. Also, the fact that the creation of new block data is not necessarily required when the movement of the viewpoint position is small is as described with reference to FIGS.

  Subsequently, a modification of the present embodiment will be described with reference to FIG. In this modification, the configuration of the server device 2a is the same as the configuration of the server device 2 shown in FIG. That is, the server device 2a performs a predetermined screen (in FIG. 13, in FIG. 13) from the three-dimensional spatial information 31 (for example, elevation map data) by the two-dimensional projection image generation processing unit 23 in response to a request from the display terminal device 4a. The two-dimensional projection image 33 projected on the distance screen 342, the long-distance screen 343, and the background screen 344) is generated, and the generated two-dimensional projection image 33 is transmitted to the display terminal device 4a.

  On the other hand, in the configuration of the display terminal device 4a, the storage unit (not shown) holds the attention object three-dimensional information 52, and the arithmetic processing unit (not shown) includes the attention object display image generation processing unit 45. It is different from the configuration of the display terminal device 4 shown in FIG. Here, the attention object 310 refers to a building or a feature that is in the vicinity of the front of the viewpoint 8 and that the user is particularly interested in.

  The attention object three-dimensional information 52 is information in which the three-dimensional appearance shape of the attention object 310 is described by predetermined three-dimensional shape data. Then, the arithmetic processing unit of the display terminal device 4 a generates a projected image of the target object 310 on the target object display screen 340 by the target object display image generation processing unit 45. In FIG. 13, the object-of-interest display screen 340 is provided as an alternative to the short-distance screen. However, the short-distance screen is provided, and is provided closer to the viewpoint 8 than the short-distance screen. Screen.

  In addition, the arithmetic processing unit of the display terminal device 4a includes the two-dimensional projection image 33 transmitted from the server device 2a and the attention object display image generation processing unit 45 generated by the two-dimensional projection image superimposed display processing unit 44. A superimposed image with the projection image on the object display screen 340 is generated and displayed on a display device (not shown).

  As described above, in the modification of the present embodiment, in order to realize the function of the target object display image generation processing unit 45, a program for displaying three-dimensional shape data is required. Since it is limited to the display of the attention object 310, the processing load on the display terminal device 4a is limited to a limited range. Therefore, the display terminal device 4a can realistically display the movement of the landscape including the attention object 310 that can be seen from the viewpoint 8 where the user moves without causing the user to feel stress.

DESCRIPTION OF SYMBOLS 1 Image generation display system 2 Server apparatus 3 Communication network 4 Display terminal apparatus 20 Arithmetic processing part 21 2D projection image generation request reception process part 22 3D spatial information block process part 23 2D projection image generation process part 24 2D projection Image transmission processing unit 30 Storage unit 31 Three-dimensional spatial information 32 Blocked three-dimensional spatial information 33 Two-dimensional projection image 40 Arithmetic processing unit 41 Viewpoint position & gazing point position acquisition unit 42 Two-dimensional projection image generation request transmission processing unit 43 Two-dimensional Projection image reception processing unit 44 Two-dimensional projection image superimposed display processing unit 45 Object-of-interest display image generation processing unit 50 Storage unit 51 Two-dimensional projection image 52 Object-of-interest three-dimensional information 60 Input device 70 Display device 80 Point of interest 310 Object of interest 321 Near Distance block data 322 Medium distance block data 32 Long-distance block data 324 Background block data 331,511 Short-distance screen image 332,512 Medium-distance screen image 333,513 Long-distance screen image 334,514 Background screen image 340 Attention object display screen 341 Short-distance screen 342 Medium-distance screen 343 Distant Distance screen 344 Background screen

Claims (16)

A server device holding three-dimensional space information representing the shape of a predetermined three-dimensional space;
A display terminal device for inputting position information of a viewpoint in the three-dimensional space and displaying a landscape in the three-dimensional space visible from the viewpoint;
An image generation and display method in an image generation and display system configured to include:
The server device
When the information including the position of the viewpoint in the three-dimensional space is received from the display terminal device, the space ahead of the viewpoint is divided into a plurality of blocks according to the distance from the viewpoint, and each block of the plurality of blocks Generating the blocked three-dimensional spatial information belonging to the three-dimensional spatial information,
A virtual screen is set at the boundary of the block opposite to the viewpoint, and a two-dimensional projection image projected onto the screen by a line of sight from the viewpoint is generated using the block-formed three-dimensional spatial information of the block. And
Transmitting the generated two-dimensional projection image to the display terminal device;
The display terminal device
Receiving the two-dimensional projection image transmitted from the server device;
The two-dimensional projection image corresponding to each block is superimposed so that the image of the block far from the viewpoint is in the back to generate a superimposed image,
An image generation and display method, comprising: displaying the generated superimposed image on a display device. The server device
2. The image generation according to claim 1, wherein when the space ahead of the viewpoint is divided into a plurality of blocks, the blocked three-dimensional space information is generated so that adjacent blocks have overlapping portions. Display method. The server device
When generating the two-dimensional projection image, the two-dimensional projection image projected onto the screen closer to the viewpoint is generated as a higher-precision image, and the accuracy of the two-dimensional projection image projected onto the screen farther from the viewpoint is reduced. The image generation / display method according to claim 1, wherein the image generation / display method is generated as an image. The display terminal device
When the viewpoint moves, the two-dimensional projection image corresponding to each block is moved left and right and up and down according to the movement of the viewpoint, and enlarged or reduced to generate the superimposed image. The image generation and display method according to claim 1, wherein The display terminal device further includes:
Holding three-dimensional shape information of a predetermined object of interest located near the front of the viewpoint;
Generating a two-dimensional projection image of the target object projected on a screen virtually provided on the opposite side of the viewpoint of the target object based on the three-dimensional shape information of the target object;
The image generation and display method according to claim 1, wherein the generated two-dimensional projection image of the object of interest and the two-dimensional projection image received from the server device are superimposed to generate a superimposed image. . A server device holding three-dimensional space information representing the shape of a predetermined three-dimensional space;
A display terminal device for inputting position information of a viewpoint in the three-dimensional space and displaying a landscape in the three-dimensional space visible from the viewpoint;
An image generation and display system configured to include:
The server device
When the information including the position of the viewpoint in the three-dimensional space is received from the display terminal device, the space ahead of the viewpoint is divided into a plurality of blocks according to the distance from the viewpoint, and each block of the plurality of blocks Generating the blocked three-dimensional spatial information belonging to the three-dimensional spatial information,
A virtual screen is set at the boundary of the block opposite to the viewpoint, and a two-dimensional projection image projected onto the screen by a line of sight from the viewpoint is generated using the block-formed three-dimensional spatial information of the block. And
Transmitting the generated two-dimensional projection image to the display terminal device;
The display terminal device
Receiving the two-dimensional projection image transmitted from the server device;
The two-dimensional projection image corresponding to each block is superimposed so that the image of the block far from the viewpoint is in the back to generate a superimposed image,
An image generation and display system, wherein the generated superimposed image is displayed on a display device. The server device
7. The image generation according to claim 6, wherein when the space in front of the viewpoint is divided into a plurality of blocks, the blocked three-dimensional space information is generated so that adjacent blocks have overlapping portions. Display system. The server device
When generating the two-dimensional projection image, the two-dimensional projection image projected onto the screen closer to the viewpoint is generated as a higher-precision image, and the accuracy of the two-dimensional projection image projected onto the screen farther from the viewpoint is reduced. The image generation / display system according to claim 6, wherein the image generation / display system is generated as an image. The display terminal device
When the viewpoint moves, the two-dimensional projection image corresponding to each block is moved left and right and up and down according to the movement of the viewpoint, and enlarged or reduced to generate the superimposed image. The image generation and display system according to claim 6, wherein The display terminal device further includes:
Holding three-dimensional shape information of a predetermined object of interest located near the front of the viewpoint;
Generating a two-dimensional projection image of the target object projected on a screen virtually provided on the opposite side of the viewpoint of the target object based on the three-dimensional shape information of the target object;
The image generation and display system according to claim 6, wherein the generated two-dimensional projection image of the object of interest and the two-dimensional projection image received from the server device are superimposed to generate a superimposed image. . A server device holding three-dimensional space information representing a shape of a predetermined three-dimensional space,
When the position information of the viewpoint in the three-dimensional space is input and information including the position information of the viewpoint is received from a display terminal device that displays a landscape in the three-dimensional space that can be seen from the viewpoint, Dividing the front space into a plurality of blocks according to the distance from the viewpoint, and generating block-formed three-dimensional spatial information belonging to each of the plurality of blocks from the three-dimensional spatial information,
A virtual screen is set at the boundary of the block opposite to the viewpoint, and a two-dimensional projection image projected onto the screen by the line of sight from the viewpoint is generated using the block-formed three-dimensional spatial information of the block. And
The server device, wherein the generated two-dimensional projection image is transmitted to the display terminal device. The server device
The server apparatus according to claim 11, wherein when the space ahead of the viewpoint is divided into a plurality of blocks, the blocked three-dimensional space information is generated so that adjacent blocks have overlapping portions. . The server device
When generating the two-dimensional projection image, the two-dimensional projection image projected onto the screen closer to the viewpoint is generated as a higher-precision image, and the accuracy of the two-dimensional projection image projected onto the screen farther from the viewpoint is reduced. The server device according to claim 11, wherein the server device is generated as an image. Holding three-dimensional space information representing the shape of a predetermined three-dimensional space, dividing a space ahead of the viewpoint set in the three-dimensional space into a plurality of blocks according to a distance from the viewpoint; Blocked three-dimensional spatial information belonging to each block of the block is generated from the three-dimensional spatial information, a virtual screen is set at a boundary opposite to the viewpoint of the block, and the block-converted three-dimensional A server device that generates a two-dimensional projection image by projecting onto the screen with a line of sight from the viewpoint using the spatial information is visible from the viewpoint in the three-dimensional space using the transmitted two-dimensional projection image A display terminal device for displaying a landscape in the three-dimensional space,
The two-dimensional projection image corresponding to each block is superimposed so that the image of the block far from the viewpoint is in the back to generate a superimposed image,
An image display terminal device that displays the generated superimposed image on a display device. The display terminal device
When the viewpoint moves, the two-dimensional projection image corresponding to each block is moved left and right and up and down according to the movement of the viewpoint, and enlarged or reduced to generate the superimposed image. The image display terminal device according to claim 14, characterized in that: The display terminal device further includes:
Holding three-dimensional shape information of a predetermined object of interest located near the front of the viewpoint;
Generating a two-dimensional projection image of the target object projected on a screen virtually provided on the opposite side of the viewpoint of the target object based on the three-dimensional shape information of the target object;
The image display terminal device according to claim 14, wherein a superimposed image is generated by superimposing the generated two-dimensional projection image of the object of interest and the two-dimensional projection image received from the server device. .