JP2010072259A - Figure data generating method, generating device, display method, and display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce resource consumption and operation quantity accompanied by scale change of figure display, while suppressing redundant quantity of figure data in a display device. <P>SOLUTION: When a figure data display device 4 displays a figure with some display scale and enlargement display is instructed from the outside, since display figure vertex coordinate group data of a comparatively high-order level exists already on a buffer 42, as display figure vertex coordinate group data of a low order level may only be read out to the buffer 42 from a recording medium 2, the number of times of access for the recording medium 2 is reduced. When the figure data display device 4 displays a figure with some display scale and reduction display is instructed from the outside, since display figure vertex coordinate group data of a comparatively high-order level exists already on the buffer 42, if display is reduction display in the same range, reduction display can be performed without performing access for the recording medium 2. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a graphic data generation method, a generation apparatus, a display method, and a display apparatus, and more particularly to a graphic data generation method, a generation apparatus, and a display method and display for generated graphic data displayed on a screen. Relating to the device.

  In a display device such as a car navigation system that displays graphic data indicating a map on the screen, as shown in FIG. 12, when a range of figures 101 and 111 of a certain scale is displayed, any of them is displayed. By designating the areas 102 and 112 to be enlarged and switching to the display of the enlarged figures 103 and 113 for the areas 102 and 112, even if the figure shows the same road or area, it is simplified or detailed. It can be displayed so that the user can easily see it.

  As a method for realizing such a display, a method of preparing a plurality of graphic data completed for each scale, and selecting and displaying graphic data corresponding to a specified scale is generally used. However, this method must prepare graphic data for each scale. Furthermore, when associating attributes related to a graphic (for example, names of roads and areas indicated by the graphic) with graphic data, it is necessary to prepare a plurality of graphic data for each scale for the same graphic, resulting in a huge amount of data. .

  In order to solve this problem, a method is known in which vertex data is thinned out or approximated according to a reduced scale for displaying certain detailed graphic data (for example, see Patent Documents 1 and 2). In Patent Document 1 described above, after obtaining a global contour line in which details exceeding a desired resolution in a figure are removed and fine irregularities are removed, an angular change in each part from the global contour line is obtained. Figure data layer that reduces the amount of figure data by extracting feature points that humans react strongly to the shape based on the calculation results and approximating the shape based on the feature points A general approximation method is described.

  Further, in Patent Document 2 described above, dots of graphic data stored in the graphic file group are thinned out in accordance with a requested reduction scale inputted from the outside, and each graphic data after the thinning process is thinned out by a shape approximation process. A small scale figure creation and display device configured to create a small scale figure is described. According to this small-scale figure creation and display device, after reduction at a small scale, it is possible to reduce the amount of figure data by simplifying the figure by shape approximation and display it quickly.

JP-A-8-106527 JP-A-11-95974

  However, when a method for displaying certain detailed graphic data by thinning or approximating vertices according to the scale as shown in Patent Documents 1 and 2 above is applied to a display device that displays map data or the like, Since the display device displays a wider range as the scale is reduced (lower magnification), the amount of graphic data for display read out to the cache memory in the display device increases and the amount of data not used for display (redundancy) Amount) is large and is not efficient in terms of resource consumption. At the same time, the display device described above requires a calculation for thinning out the vertices from the original detailed figure, and there is a problem that the calculation amount increases.

  The present invention has been made in view of the above points, and a graphic data generation method and a generation apparatus capable of reducing the redundant amount of graphic data in the display device and reducing the resource consumption and the calculation amount associated with the scale change of the graphic display. An object of the present invention is to provide a display method and a display device.

  In order to achieve the above object, the graphic data generation method of the first invention is a setting step for setting a plurality of display scale values for displaying a graphic at a plurality of scales, and data constituting the graphic. An acquisition step for acquiring original figure vertex coordinate data including information on a plurality of vertex coordinates constituting the figure from the original figure data, and a display figure corresponding to each display scale value for each of the plurality of display scale values Display figure vertex coordinate group data, which is a set of remaining vertex coordinates obtained by thinning out all vertex coordinates constituting a display figure at a display scale value one scale smaller than each display scale value from all vertex coordinates constituting A first data generation step for generating the display graphic vertex coordinate group data generated for each display scale value and a display diagram which is information for associating with the display scale value Characterized in that it comprises a second data generation step of generating management data.

  In order to achieve the above object, the graphic data generating apparatus according to the second invention includes a setting means for setting a plurality of display scale values for displaying a graphic at a plurality of scales, and data constituting the graphic. Acquisition means for acquiring original figure vertex coordinate data including information on a plurality of vertex coordinates constituting the figure from the original figure data, and a figure corresponding to each display scale value for each of the plurality of display scale values. Display figure vertex coordinates that are set information of the remaining vertex coordinates obtained by thinning out all vertex coordinates constituting the display figure at a display scale value that is one scale smaller than each display scale value from all vertex coordinates constituting the display figure Display data management that is information for associating first data generation means for generating group data and display graphic vertex coordinate group data generated for each display scale value with the display scale value And having a second data generating means for generating over data.

  In order to achieve the above object, a graphic data display method according to a third aspect of the invention includes a setting step of setting one of a plurality of display scale values for displaying a graphic at a plurality of scales, For each display scale value, from all the vertex coordinates constituting the display figure that is a figure corresponding to each display scale value, all the display figures constituting the display scale value at one scale smaller than each display scale value Display graphic vertex coordinate group data, which is a set of remaining vertex coordinates obtained by thinning out vertex coordinates, and display graphic management data, which is information for associating the display graphic vertex coordinate group data with a display scale value, The display scale value set in the data acquisition step and the setting step acquired from the memory and stored in the temporary storage memory is smaller than the display scale value of the display figure already displayed The display figure vertex coordinate group data acquired in the data acquisition step and stored in the temporary storage memory during the previous display processing, the display required for display at the display scale value set in the setting step A step for specifying figure vertex coordinate group data and a display for displaying a figure at the display scale value set in the setting step using the figure vertex coordinate data of the display figure vertex coordinate group data specified in the specifying step. And a step.

  In order to achieve the above object, a graphic data display method according to a fourth aspect of the invention includes a setting step for setting one of a plurality of display scale values for displaying a graphic at a plurality of scales, and a plurality of display steps. For each display scale value, from all the vertex coordinates constituting the display figure that is a figure corresponding to each display scale value, all the display figures constituting the display scale value at one scale smaller than each display scale value Display graphic vertex coordinate group data, which is a set of remaining vertex coordinates obtained by thinning out vertex coordinates, and display graphic management data, which is information for associating the display graphic vertex coordinate group data with a display scale value, The first data acquisition step acquired from the first storage memory and the display scale value set in the setting step is greater than the display scale value of the display figure already displayed. In the case of threshold, the display figure vertex coordinate group data acquired in the first data acquisition step and stored in the temporary storage memory at the time of the previous display processing is displayed at the display scale value set in the setting step. Display graphic vertex coordinate group that is necessary for display at the display scale value set in the setting step and the first specifying step that specifies display graphic vertex coordinate group data that is necessary, and that is not stored in the temporary storage memory A second specifying step for specifying data; a second data acquiring step for newly acquiring display graphic vertex coordinate group data specified in the second specifying step from an external recording medium and storing the data in a temporary storage memory; Using the display figure vertex coordinate data of the display figure vertex coordinate group data specified by the first and second specifying steps, the setting step Characterized in that it comprises a display step of performing graphical display in the set display scale value.

  In order to achieve the above object, a graphic data display device according to a fifth aspect of the present invention comprises a setting means for setting one of a plurality of display scale values for displaying a graphic at a plurality of scales, and a plurality of display means. For each display scale value, from all the vertex coordinates constituting the display figure that is a figure corresponding to each display scale value, all the display figures constituting the display scale value at one scale smaller than each display scale value Display graphic vertex coordinate group data, which is a set of remaining vertex coordinates obtained by thinning out vertex coordinates, and display graphic management data, which is information for associating the display graphic vertex coordinate group data with a display scale value, If the display scale value set by the data acquisition means and the setting means acquired from the storage means and stored in the temporary storage memory is smaller than the display scale value of the already displayed display figure, Display figure vertex coordinate group required for display at the display scale value set by the setting means among the display figure vertex coordinate group data acquired by the data acquisition means during the display process and stored in the temporary storage memory Specifying means for specifying data, and display means for performing graphic display at the display scale value set by the setting means using the display graphic vertex coordinate data of the display graphic vertex coordinate group data specified by the specifying means It is characterized by that.

  Furthermore, in order to achieve the above object, a graphic data display device according to a sixth aspect of the present invention comprises setting means for setting one of a plurality of display scale values for displaying a graphic at a plurality of scales, and a plurality of display means. For each display scale value, from all the vertex coordinates constituting the display figure that is a figure corresponding to each display scale value, all the display figures constituting the display scale value at one scale smaller than each display scale value Display graphic vertex coordinate group data, which is a set of remaining vertex coordinates obtained by thinning out vertex coordinates, and display graphic management data, which is information for associating the display graphic vertex coordinate group data with a display scale value, When the display scale value set by the first data acquisition means and the setting means that is acquired from and stored in the temporary storage memory is larger than the display scale value of the display graphic already displayed, Of the display figure vertex coordinate group data acquired by the first data acquisition means and stored in the temporary storage memory at the time of each display process, it is necessary for display at the display scale value set by the setting means. The first specifying means for specifying the display figure vertex coordinate group data and the display figure vertex coordinate group data which is necessary for display at the display scale value set by the setting means and which is not stored in the temporary storage memory is specified. A second data acquisition unit that newly acquires display graphic vertex coordinate group data specified by the second specification unit from an external recording medium and stores the data in a temporary storage memory; Display means for performing graphic display at the display scale value set by the setting means using the display graphic vertex coordinate data of the display graphic vertex coordinate group data specified by the second specifying means Characterized in that it has a.

  According to the present invention, it is possible to suppress the redundant amount of graphic data in the display device, and it is possible to reduce the resource consumption and the calculation amount associated with the scale change of the graphic display.

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

  FIG. 1 shows a configuration diagram of an example of a graphic generation / display system to which a graphic data generation device and a display device according to the present invention are applied. In FIG. 1, a graphic data generation device 3 is a graphic data generation device according to the present invention, which receives original graphic group data recorded on a recording medium 1 as input and generates display graphic group data as will be described later. Recording is performed on the recording medium 2. The graphic data display device 4 is a graphic data display device according to the present invention, which reads display graphic group data recorded on the recording medium 2 and performs display processing described later to display the graphic on the screen of the monitor device 5. To do.

  FIG. 2 shows a block diagram of an embodiment of a graphic data generating apparatus according to the present invention. In the figure, the same components as those in FIG. The graphic data generation device 3 includes a reading unit 30 for reading original graphic group data (which consists of original graphic group management data and original graphic data group as will be described later) recorded on the recording medium 1, and an original graphic A buffer 31 for temporarily storing group management data, an instruction unit 32, a level determination unit 33, a buffer 34 for temporarily storing original graphic data, a buffer 35 for temporarily storing level management data and a display graphic management data group, Buffers 36 to 38 for temporarily storing display graphic vertex data for each level, a recording unit 39 for recording the generated display graphic group data on the recording medium 2, and an operation input unit for inputting a desired display scale to the command unit 32 3A.

  The command unit 32 notifies the level determination unit 33 of the level determination condition for each vertex of the original graphic data from one or more display scale values input from the operation input unit 3A. In addition, the command unit 32 issues a command to the reading unit 30 to read the original graphic group management data from the recording medium 1 and supply the original graphic group management data to the buffer 31, and the original graphic data corresponding to the original graphic group management data The data is read and supplied to the buffer 34. Further, the command unit 32 issues a command to the recording unit 39 so as to record each data temporarily held in the buffers 35 to 38 on the recording medium 2.

  The level discriminating unit 33 analyzes the original graphic data stored in the buffer 34, and the condition specified by the command unit 32 to which level (display graphic vertex coordinate group data) each vertex of the original graphic data should belong. The vertex coordinate data is stored in one of the buffers 36 to 38 according to the level of each vertex. Further, the level determination unit 33 updates the level management data and the display graphic management data group stored in the buffer 35 according to the processing result.

  The buffer 31 temporarily stores original graphic group management data. The buffer 34 temporarily holds one or more original graphic data specified by the instruction unit 32. The buffer 35 temporarily holds the level management data of the display graphic group data to be recorded on the recording medium 2 and the display graphic management data group. The buffers 36 to 38 temporarily hold display graphic vertex coordinate group data of each display graphic for each level described later.

  The recording unit 39 includes display graphic group data level management data and display graphic management data group temporarily stored in the buffer 35, and display graphic vertex coordinate group data of each display graphic temporarily stored in the buffers 36 to 38. Is recorded on the recording medium 2. The operation input unit 3A specifies one or more display scale values corresponding to the generated display graphic group data to the command unit 32.

  Here, the configuration of the original graphic group data that the reading unit 30 reads from the recording medium 1 will be described with reference to FIG. FIG. 3 shows an example of the data structure of the original figure group data. As shown in the figure, the original graphic group data 201 is composed of one original graphic group management data 211 and one or more original graphic data 221.

  The original graphic group management data 211 is data for managing the entire original graphic group data, and includes the original graphic data number NF and the original graphic data reference information 212 for the number of original graphic data. The original graphic data reference information 212 is assumed to be the file name itself (for example, 0001.fig,..., Xxxx.fig, etc.).

  The original graphic data 221 is data having a one-to-one relationship with the original graphic, and includes the vertex coordinate number Np constituting the original graphic and the original graphic vertex coordinate data 222 corresponding to the number of vertices. The original figure vertex coordinate data 222 stored in the original figure data 221 is arranged in an easy-to-draw arrangement order, for example, from one end point to the opposite end direction when the original figure is a line shape, and clockwise when the original figure is a surface shape. Stored in order. Each original figure vertex coordinate data 222 stores one vertex coordinate value. Further, the file names of the respective original graphic data 221 are 0001.fig and xxxx.fig.

  Next, the configuration of the display graphic group data will be described with reference to FIG. FIG. 4 shows an example of the data structure of the display graphic group data. As shown in the figure, the display graphic group data 301 is composed of one level management data 311, one or more display graphic management data 321, and one or more display graphic vertex coordinate group data 331. The display graphic group data 301 is recorded on the recording medium 2 by the recording unit 39.

  The level management data is data for classifying and managing vertices constituting a display figure that is required more as the scale is reduced. For example, the most detailed graphic shape can be displayed by using all the vertices included from the highest level to the lowest level managed by the level management data. On the contrary, it is possible to display a schematic figure shape by using only the highest level or only the vertices included in the lowermost level than the highest level. In this description, it is assumed that the level value of the highest level is “1”, and the level is lower as the level value is larger. More specifically, the level management data 311 is based on the total number of levels NL (NL is a natural number) in the display graphic group data 301 and the display graphic vertex group data reference information 312 regarding the display graphic vertex coordinate group data 331 of each level. Become. The display figure vertex coordinate group data reference information 312 is the file name itself (for example, lv01.pnt, lv0L.pnt, etc.) in which the display figure vertex coordinate group data 331 is stored.

  The display graphic management data managed data 320 includes one or more display graphic management data 321 to be described later and the total number NF of the display graphic management data 321. Each display graphic management data 321 is data having a one-to-one relationship with each display graphic, and is composed of total vertex coordinates NP (NP is a natural number) constituting the display graphic and display graphic vertex coordinate data reference information 322 of each level. . The display figure vertex coordinate data reference information 322 includes the number of vertex coordinates at that level and the number of offsets (start offset) of the display figure vertex coordinate data from the top of the display figure vertex coordinate group data.

  The display figure vertex coordinate group data 331 exists one-to-one with each level, and stores one or more display figure vertex coordinate data 332. Each display figure vertex coordinate data 332 stores one vertex coordinate value.

  In the display figure group data 301, display figure vertex coordinate data 332 constituting a display figure is stored separately for each level as display figure vertex coordinate group data 331. Therefore, there arises a problem that it becomes impossible to specify the order of apexes for accurately drawing a figure.

  In order to solve the problem, it is necessary to store information that can specify the order of vertices from level 1 to a certain level L (L is a natural number) in at least one of display graphic management data 321 and display graphic vertex coordinate data 332. is there. In this description, as an example, when a figure is drawn from level 1 to level L, a vertex below the level L is placed between the vertex indicated by the display figure vertex coordinate data and the adjacent level 1 to level L vertex. Information that can specify the number for each level is stored in the display figure vertex coordinate data 332.

  Instead of the number of vertices for each lower level, reference information to adjacent display graphic vertex coordinate data may be stored in each display graphic vertex coordinate data when performing the most detailed display.

  FIG. 5 shows an example of the relationship between the display graphic management data 321 and the display graphic vertex coordinate group data 331 regarding a display graphic having a certain line shape. FIG. 6 shows an example of display graphic management data 321 and display graphic vertex coordinate group data 331 relating to a display graphic having a certain surface shape. 5 and 6, the graphic shape at the highest level 1 is represented by the simplest straight line 401 and quadrilateral 501 with respect to the graphic shapes 400 and 500 at the time of the most detailed display. Further, the graphic shape at the next lower level 2 is shown by the more complicated graphics 402 and 502 than the graphic at the highest level 1 in FIGS. 5 and 6. Furthermore, the figure shapes 403 and 503 at the lowest level 3 indicate the most detailed figure shapes which are the same as the figure shapes 400 and 500 at the time of the most detailed display.

  5 and 6, the display graphic management data 321 is the number of display graphic vertex coordinate data of the graphic shapes 400 and 500 at the time of the most detailed display (“7” in FIG. 5, “9” in FIG. 6). And information for specifying the display figure vertex coordinate data position for each of the three levels in total. Information for specifying the display figure vertex coordinate data position for each level includes the number of vertex coordinates of each level (the number of display figure vertex coordinate data of the display figure stored in the display figure vertex coordinate group data 331 of each level), and each level. Starting offset. The start offset of each level indicates an offset from the top display figure vertex coordinate data stored in the display figure vertex coordinate group data 331 of each level to the top display figure vertex coordinate data of the display figure vertex coordinate data string of the display figure. .

  5 and 6, the display figure vertex coordinate group data 331 for each level includes the vertex coordinate value (x, y) and the level 1 to the level L-1 (in this description, L is “3”). When the figure using the display figure vertex coordinate group data 331 up to is displayed, the vertex of the level L-1 existing between the vertex coordinate [n] of the level (level L) and the vertex coordinate [n + 1] It consists of the number of coordinates.

  Next, the operation of the embodiment of the graphic data generating apparatus of the present invention shown in FIG. 2 will be described with reference to the flowchart of FIG. First, as preprocessing, one or more kinds of display scale values (number of levels) assumed in an apparatus and application for displaying display graphic group data are set (step S10). In this description, the display scale value (number of levels) set in step S10 is NL.

  Next, the instruction unit 32 in FIG. 2 causes the reading unit 30 to read the original graphic group management data 211 in the original graphic group data 201 from the external recording medium 1 and loads it into the buffer 31 which is a cache memory (temporary storage). (Step S11). The original graphic group management data 211 loaded in the buffer 31 includes the number of original graphic data and the original graphic data reference information 212 as shown in FIG. In this description, the number of original graphic data acquired by loading is NF (NF is a natural number).

  Subsequently, the instruction unit 32 initializes a variable i (i is a natural number) to 0, and then determines whether the variable i is less than the number of original graphic data NF. (Step S12). When the variable i is less than NF, the command unit 32 determines that the original graphic group management data 221 has not been completely processed, and the original graphic data 221 (xxxx) indicated by the original graphic data reference information 212 [i]. .fig etc.) is prepared in the buffer 34 which is a cache memory. Then, the original graphic data 221 is read from the external recording medium 1 by the reading unit 30 and loaded into the buffer 34. (Step S13). The original graphic data 221 loaded in the buffer 34 includes the original graphic vertex coordinate data 222 and the number of vertex coordinates of the original graphic data as shown in FIG. In this description, it is assumed that the number of vertex coordinates of the original graphic data acquired by loading is NP.

  Further, the instruction unit 32 causes the reading unit 30 to read the original graphic data 221 and load it into the buffer 34, and notifies the level determination unit 33 that the original graphic data 221 has been newly loaded into the buffer 34. Based on the above notification, the level determination unit 33 initializes a variable j (j is a natural number) to 0, and then determines whether the variable j is less than NP (step S14). When determining that the variable j is less than NP, the level determination unit 33 determines that the original figure vertex coordinate data included in the original figure data 221 has not been completely processed, and uses the display scale value NL set in the preprocessing. Based on the original graphic data 221 [i] stored in the buffer 34, the level of the original graphic vertex coordinate data 222 [j] is determined by a method described later (step S15).

  Subsequently, the level discriminating unit 33 generates display figure vertex coordinate data 322 as vertex coordinate information in the display figure group data from the original figure vertex coordinate data 222 [j] read from the buffer 34, and the step The display figure vertex coordinate group data 331 corresponding to the level determined in S15 is added (step S16). In addition to the display figure vertex coordinate group data, the display figure vertex coordinate data 322 is stored in the buffer of the corresponding level among the buffers 36, 37 and 38 which are memories for level 1, level 2 and level 3, respectively. Is done. At this time, the information for specifying the arrangement order of the vertices from level 1 to level 2 and 3 as described above is displayed graphic management data 331 stored in the buffer 35 and display graphic vertex coordinate data stored in the buffers 36 and 37. It is assumed that the process of storing in 322 is also performed at the same time.

  Subsequently, the level determination unit 33 updates the display graphic management data 321 corresponding to the original graphic data 221 [i] in the display graphic management data managed data 320 stored in the buffer 35 (step S17). Thereafter, the level determination unit 33 increments the variable j by 1 and performs the determination in step 14. In this way, the processes of steps S13 to S17 are performed on the original graphic data 221 [j].

  Subsequently, when the level determination unit 33 determines in step 14 that the variable j has reached NP, it indicates that the processing of all the original figure vertex coordinate data 222 [j] of the original figure data 221 [i] has been completed. The command unit 32 is notified. The command unit 32 causes the recording unit 39 to record a total of NP display graphic vertex coordinate group data 331 stored for each level in the buffers 36 to 38 on the external recording medium 2 (step 18). This external recording medium 2 is recorded with display graphic vertex coordinate data stored in buffers 36, 37 and 38 in a file (lv01.pnt, lv0L.pnt, etc.) for display graphic vertex coordinate group data 331 at each level. This is done by adding 332.

  Thereafter, the instruction unit 32 increments the variable i by 1 and initializes the variable j to 0, and performs the determination in step 12. In this way, the processes in steps S13 to S18 are executed for all the original graphic data 221 included in the original graphic group data 201.

  If it is determined in step 12 that the variable i has reached NF, the command unit 33 determines that the processing of steps S13 to S18 has been completed for all the original graphic data 221 of the original graphic group data 201, and the buffer 35 The level management data 311 and the display graphic management data management data 320 stored in the recording medium 39 are recorded on the external recording medium 2 by the recording unit 39 (step 19).

  Display graphic group data 301 is generated by the above processing.

  It should be noted that the level determination method in step S16 is as follows: in each original figure, the distance between a straight line connecting two vertices and the target vertex, the straight line distance between two adjacent vertices, the inner angle between the target vertices, A threshold value for a parameter such as a straight line distance is prepared for each level, and the level corresponding to the original figure vertex coordinate data 222 is determined by comparing the parameter with the threshold value of each level.

  For example, consider the case where the display scale values set in the pre-processing are three types of X, Y and Z (1 ≧ X> Y> Z), that is, the number of levels NL is “3”.

  The display figure vertex coordinate data 332 stored in the level 1 display figure vertex coordinate group data 331 is display figure vertex coordinate data that is determined to have a large effect on the figure shape when the vertex coordinates are thinned out in scale X display. .

  The display figure vertex coordinate data 332 stored in the display figure vertex coordinate group data 331 of level 2 does not have a large influence on the figure shape when the vertex coordinates are thinned out in the scale X display, but the vertex coordinates are displayed in the scale Y display. Of the display figure vertex coordinate data 332 that is determined to have a large influence on the figure shape when thinning, it is display figure vertex coordinate data that is not stored in the display figure vertex coordinate group data 331 of level 1.

  The display figure vertex coordinate data 332 stored in the display figure vertex group data 331 of level 3 does not have a large effect on the figure shape when the vertex coordinates are thinned out in the scale Y display, but the vertex coordinates are thinned out in the scale Z display. Among the display figure vertex coordinate data 332 determined to have a great influence on the figure shape, the display figure vertex coordinate data is not stored in the display figure vertex coordinate group data 331 at levels 1 and 2. However, in this example, since the level number NL is “3” and level 3 is the lowest level, all the display figure vertex coordinate data 332 not belonging to the display figure vertex coordinate group data 331 of the levels 1 and 2 are stored. It may be stored.

  In this description, the case where the display scale value is set in the pre-processing has been described, but the threshold value of the parameter used for the level determination method may be set instead of the display scale value. Since the display graphic management data 321 has a one-to-one relationship with the graphic to be displayed, attribute information relating to each original graphic data 221 as accompanying data in the original graphic group data 201 or outside the original graphic group data 201, for example, each graphic When the name information or the like is prepared, attribute information is stored in the display graphic management data 321 during the generation process. Thereby, even when the display scale and the figure shape are different at the time of display, the attribute information can be uniquely acquired.

  In addition, when generating external data that refers to the display graphic management data 321, by storing information that can uniquely identify the display graphic management data 321 in the external data, a predetermined graphic can be displayed regardless of the display scale. It can be specified.

  Next, display processing of the display graphic group data 301 by the graphic data display device of the present invention will be described. FIG. 8 shows a block diagram of an embodiment of a graphic data display apparatus according to the present invention. In the figure, the same components as those in FIG. The graphic data display device 4 includes a reading unit 40 for reading the display graphic group data 301 recorded on the recording medium 2, a buffer 41 for temporarily storing the level management data 311 and the display graphic management data 321 group, and display graphic vertex coordinates. The buffer 42 for temporarily storing the group data 331, the command unit 43, the display graphic vertex coordinate data selection unit 44 for selecting the display graphic vertex coordinate data 332, and the selected display graphic vertex coordinate data 332 are stored in the monitor device 5. A display unit 45 for displaying on the screen and an operation input unit 46 for specifying the scale and range to be displayed to the command unit 43 are configured.

  The command unit 43 loads the buffer 42 with reference to the level management data 311 and the display graphic management data 321 group stored in the buffer 41 according to the display scale and range specified by the operation input unit 46. The display graphic vertex coordinate group data 331 is determined and an instruction is issued to the reading unit 40. The display figure vertex coordinate data selection unit 44 receives necessary display figure vertices from the display figure vertex coordinate group data 331 temporarily held in the buffer 42 according to the notification of the figure to be displayed and the display level from the command unit 43. A group of coordinate data 332 is acquired and supplied to the display unit 45 together with a vertex coordinate data string whose sort and scale have been converted in accordance with drawing. Further, the display figure vertex coordinate data selection unit 44 issues the display command to the display unit 45 after performing the above processing on all the display figures.

  Although not shown, the display unit 45 resizes the frame buffer that stores the display figure vertex coordinate data 332 sorted in the display figure drawing order and the display figure configured by the sorted display figure vertex coordinate data 332. Part. The display unit 45 stores the display figure vertex coordinate data 332 and the vertex coordinate data string acquired from the display figure vertex coordinate data selection unit 44, and displays the figure on the screen of the monitor device 5 in response to a display command.

  Next, the operation of the graphic data display device 4 of FIG. 8 will be described with reference to the flowchart of FIG. First, the graphic data display device 4 sets a display scale value to be displayed as preprocessing (step S20). Subsequently, in accordance with a read command from the command unit 43, the read unit 40 loads the level management data 311 and the display graphic management data 321 from the external recording medium 2 into the buffer 41 which is a cache memory, and the total number of levels (= NL). The total number of display graphic management data (= NF) is acquired (step S21).

  Subsequently, the command unit 43 specifies a level range necessary for graphic display from the level management data 311 from the display scale value set in the preprocessing (step S22). In this description, the specified level range is “1” for the highest level and “Lr” for the lowest level. Subsequently, the command unit 43 prepares a memory area for the display graphic vertex coordinate group data 331 corresponding to the level range 1 to Lr specified in step S22 in the buffer 42 which is a cache memory, and displays the display graphic vertex coordinates of each level. All the group data 331 is read from the external recording medium 2 by the reading unit 40 and loaded into the buffer 42 (step S23).

  Subsequently, after initializing the variable i to 0, the command unit 43 determines whether the variable i is less than NF of the total number of display graphic management data 321 (step S24). When the variable i is less than NF, the command unit 43 determines that all display graphic management data 321 has not been processed, and the display graphic management data 321 [i] is read from the external recording medium 2 by the reading unit 40. The data is read and loaded into the buffer 42 (step S25). At this time, the command unit 43 acquires the highest level Lm of the display graphic vertex coordinate group data 331 referred to by the display graphic management data 321 from the display graphic management data 321.

  Subsequently, the command unit 43 determines whether the highest level Lm acquired in step S25 is lower than the lowest level Lr calculated in step S22, that is, whether the value of Lm is larger than Lr (step S26). When the value of Lm is larger than Lr, it is determined that the graphic managed by the display graphic management data 321 does not need to be displayed, and the command unit 43 increments the value of the variable i by 1 and returns to the process of step S24. .

  On the other hand, when the value of Lm is less than or equal to Lr, the command unit 43 causes the display graphic vertex coordinate data selection unit 44 to display the display graphic management data 321 [i] referenced by the display graphic management data 321 in the cache memory in the display unit 45. As many memory areas as the number of display figure vertex coordinate data 332 of levels 1 to Lr are prepared (step S27). Subsequently, the instruction unit 43 initializes the value of the variable j to “0”, and then determines whether or not the value of the variable j is equal to or lower than the lowest level Lr calculated in Step S22 (Step S28).

  When the value of the variable j is less than or equal to Lr, the command unit 43 stores the display graphic vertex coordinate data of level j in the memory area prepared in step S27 of the cache memory in the display unit 45 by the display graphic vertex coordinate data selection unit 44. 332 is stored (step S29). At this time, the display figure vertex coordinate data selection unit 44 displays the display figure vertex coordinate data 332 stored in the buffer 42 in consideration of the number of vertices of the subsequent lower level described in each display figure vertex coordinate data 332. Copy to the cache memory in the unit 45. Then, the instruction unit 43 increments the value of the variable j by 1, and then performs the determination in step S28 again. In this way, as a result of the processing in step S29 being performed until it is determined in step S28 that the value of the variable j is greater than Lr, the display figure vertex coordinate data 332 from level 1 to Lr is stored in the cache memory in the display unit 45. Is stored.

  When it is determined in step S28 that the value of the variable j is greater than Lr, the display graphic vertex coordinate data selection unit 44 displays the display graphic vertex coordinate data 331 of the display graphic management data 321 [j] acquired in steps S23 to S29. After the vertex coordinate values of the group are converted according to the display scale value, the display unit 45 displays a graphic corresponding to the display graphic management data 321 on the screen of the monitor device 5 (step S30). The processing from step S24 to step S30 is performed on the display graphic management data 321 included in the display graphic group data 301. The graphic data display device 4 displays the display graphic group data 301 by the processing shown in the flowchart of FIG.

  Here, a case will be described in which, for example, when the graphic data display device 4 is displaying a graphic at a certain display scale, a display at a scale larger than the displayed display scale, that is, an enlarged display is instructed from the outside. In this case, since the relatively higher level display figure vertex coordinate group data 331 already exists on the buffer 42, it is only necessary to read the lower level display figure vertex coordinate group data 331 from the external recording medium 2 to the buffer 42. Therefore, the number of accesses to the recording medium 2 by the graphic data display device 4 decreases.

  Next, a case will be described in which when a figure is being displayed at a certain display scale, a display at a scale smaller than the displayed display scale, that is, a reduction display is instructed from outside. In this case, since the display graphic vertex coordinate group data 331 at a relatively higher level already exists on the buffer 42, if the reduced display is in the same range, the reduced display can be performed without accessing the recording medium 2. Become. When the display range is insufficient, the graphic data display device 4 reads only the upper-level display graphic vertex coordinate group data 331 in the insufficient range from the recording medium 2.

  Next, the above enlarged display and reduced display by the graphic data display device 4 will be described more specifically. The graphic data display device 4 performs graphic display by changing the magnification (display scale) from high to low to medium. Further, the graphic data display device 4 displays the display graphic vertex coordinate data 332 of levels 1 to 3 shown in FIGS. 5 and 6 when displaying a graphic at an enlargement magnification “high” (display scale value “large”). In the case of graphic display at an enlargement ratio “medium” (display scale value “medium”), the display figure vertex coordinate data of levels 1 and 2 shown in FIGS. 5 and 6 are displayed, and an enlargement ratio “low” ( When a figure is displayed at the display scale value “small”), the level 1 display figure vertex coordinate data 332 shown in FIGS. 5 and 6 is displayed.

  In addition to this, a plurality of display graphic vertex coordinate group data 331 at the same level is recorded on the recording medium 2, and the graphic data display device 4 displays them by dividing each display area. For example, the recording medium 2 divides the area of the entire display range of the graphic shown in FIG. 10A into 16 as shown in FIG. Display graphic vertex group data 331 is stored.

  First, in the graphic display at the first enlargement magnification “high”, the graphic data display device 4 includes the display graphic vertex coordinate data 332 of the display graphic to be displayed, and the levels 1 to 3 shown in FIGS. The display figure vertex coordinate group data 331 is read from the recording medium 2 and stored in the buffer 42. Subsequently, the display graphic vertex coordinate data selection unit 44 acquires the display graphic vertex coordinate data 332 group of levels 1 to 3 of the display graphic from the buffer 42, and displays the display graphic vertex coordinate data 332 group sorted in the drawing order. Stored in the cache memory. Then, the display unit 45 resizes the display figure vertex coordinate data 332 group read from the internal cache memory to a specified magnification, and then causes the monitor device 5 to display it.

  Next, in the state in which the graphic data display device 4 displays the graphic with the above-mentioned magnification “high”, when performing graphic display with the magnification “low”, the display graphic vertex coordinate data selection unit 44 has already buffered. The level 2 and level 3 display figure vertex coordinate group data 331 stored in 42 is discarded, and the level 1 display figure vertex coordinate group data 331 remaining in the buffer 42 is reused.

  Further, when the graphic display is performed at the enlargement magnification “low”, since the display is wider than the graphic display at the enlargement magnification “high”, the reading unit 40 newly displays the display graphic to be displayed according to the command of the command unit 43. The level 1 display graphic vertex coordinate group data 331 including the display graphic vertex coordinate data 332 group is newly read from the recording medium 2 and stored in the buffer 42.

  For example, the graphic data display device 4 stores the display graphic vertex coordinate group data 331 of the levels 1 to 3 of the block 11 shown in FIG. 11 (C1) at the enlargement factor “high” in the buffer 42 and displays the graphic in FIG. 11 (C2). ), The display figure vertex coordinate group data 331 of level 1 from block 00 to block 23 is stored in the buffer 42 as shown in FIG. At this time, the level 1 display figure vertex coordinate group data 331 of the block 11 already stored in the buffer 42 is left, and the level 1 display figure vertex coordinate group data 331 of the blocks 00 to 10 and blocks 12 to 23 is newly added. It is read from the recording medium 2 and stored in the buffer 42.

  Subsequently, the display figure vertex coordinate data selection unit 44 obtains the level 1 display figure vertex coordinate group data 331 to be reused from the buffer 42 and the newly stored level 1 display figure vertex coordinate group data 331 and draws it. The display figure vertex coordinate data 332 is sorted in order and stored in the cache memory in the display unit 45. Then, the display unit 45 resizes the display figure vertex coordinate data 332 group read from the internal cache memory to a specified magnification, and then causes the monitor device 5 to display it. Thereby, for example, the graphic shown in FIG. 11 (A2) is displayed.

  Next, in the state where the graphic data display device 4 is displaying the graphic with the above-mentioned magnification “low”, when performing graphic display with the magnification “medium”, the display graphic vertex coordinate data selection unit 44 has already buffered. The level 1 display figure vertex coordinate group data 331 stored in 42 is reused. Further, when the graphic display is performed at the enlargement magnification “medium”, the display range becomes narrower than when the graphic display at the enlargement magnification “low” is displayed. Therefore, the reading unit 40 newly displays the display graphic to be displayed in accordance with the command from the command unit 43. Level 2 display figure vertex coordinate group data 331 including the display figure vertex coordinate data 332 group is newly read from the recording medium 2 and stored in the buffer 42.

  As a result, for example, the graphic data display device 4 displays the level 1 display graphic vertex coordinate group data 331 from block 00 to block 23 in the buffer 42 when displaying the graphic shown in FIG. In the stored state, the level 1 display figure vertex coordinate group data 331 other than the block 11 in the display target area is discarded, and the level 2 display figure vertex coordinate group data 331 of the block 11 shown in FIG. The data is newly read from the recording medium 2 and stored in the buffer 42.

  Subsequently, the display figure vertex coordinate data selection unit 44 stores the level 1 display figure vertex coordinate group data 331 of the block 11 to be reused from the buffer 42 and the newly stored level 2 display figure vertex coordinate group data of the block 11. 331 are acquired, sorted in the drawing order, and the display figure vertex coordinate data 332 group is stored in the cache memory in the display unit 45. Then, the display unit 45 resizes the display figure vertex coordinate data 332 group read from the internal cache memory to a specified magnification, and then causes the monitor device 5 to display it. Thereby, for example, the graphic shown in FIG. 11 (B2) is displayed.

  As described above, according to the present embodiment, the graphic data generation device 3 uses the display graphic vertex coordinate data 332 having the number of vertices corresponding to a plurality of display scale values (levels) in which one original graphic data 221 is set in advance. Is converted into display graphic group data 301 having display graphic coordinate group data 331 and recorded on the recording medium 2. Here, as shown in FIGS. 5 and 6, the display figure vertex coordinate data 332 having the number of vertices corresponding to the plurality of display scale values is a plurality of vertexes indicating the display figure shape at the display scale value. Display graphic vertex coordinate data indicating vertex coordinate positions obtained by subtracting each display graphic vertex coordinate data 332 of a plurality of vertices indicating a display graphic shape at a reduced scale value smaller than the display scale value from each display graphic vertex coordinate data 332 .

  Therefore, when the graphic data display device 4 displays the original graphic data at the specified display scale value, when the specified display scale value is enlarged and displayed larger than the displayed display scale value, the display is performed. Since the display figure vertex coordinate data 332 of a plurality of vertices indicating the display figure shape at the display scale value in the middle is already stored in the buffer 42, it can be reused and the number of accesses to the recording medium 2 Can be reduced.

  In addition, when performing a reduced display in which the designated display scale value is smaller than the display scale value being displayed, a display figure that has been conventionally read to the cache memory in the display device is displayed in order to display a wider range than the figure being displayed. Although the amount of data increases, in the present embodiment, among the display figure vertex coordinate data 332 of the plurality of vertices indicating the display figure shape at the display scale value being displayed already stored in the buffer 42, Since the display figure vertex coordinate data 332 of a plurality of vertices indicating the display figure shape at the designated display scale value can be reused and displayed without accessing the recording medium 2, The amount of display graphic group data 301 read to the cache memory can be reduced, and the proportion of the data amount (redundant amount) not used for display is also reduced. Costs can be reduced. Further, in the present embodiment, the calculation for thinning out the vertexes from the original detailed original graphic data 221 in the graphic data display device 4 can be made unnecessary, and the processing burden associated with the scale change at the time of display can be reduced. .

1 is a configuration diagram of an example of a graphic generation / display system to which a graphic data generation device and a display device of the present invention are applied. 1 is a block diagram of an embodiment of a graphic data generation apparatus of the present invention. It is a figure which shows an example of the data structure of the original figure group data in embodiment of this invention. It is a figure which shows an example of the structure of the display figure group data in embodiment of this invention. It is a figure which shows an example of the display figure management data regarding the figure with a line shape in embodiment of this invention, and display figure vertex coordinate group data. It is a figure which shows an example of the display figure management data regarding the figure with a surface shape in the embodiment of this invention, and display figure vertex coordinate group data. It is a flowchart for operation | movement description of one Embodiment of the graphics data generation apparatus of this invention. It is a block diagram of one embodiment of a graphic data display device of the present invention. It is a flowchart for operation | movement description of one Embodiment of the graphic data display apparatus of this invention. It is a figure which shows the displayable whole range of the graphic data stored in the recording medium, and each division area (block) of the display graphic vertex group data of levels 1-3. It is a figure which shows an example of the display block and display figure in each expansion magnification (display scale) when the figure data display apparatus of this invention changes a magnification (display scale) and displays a figure. It is a figure which shows an example in case the shape of a figure changes with display scales.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, 2 Recording medium 3 Graphic data generation apparatus 4 Graphic data display apparatus 5 Monitor apparatus 30, 40 Reading part 31, 34-38, 41, 42 Buffer 32, 43 Command part 33 Level discrimination part 39 Recording part 3A, 46 Operation input Section 44 Display figure vertex coordinate data selection section 45 Display section 201 Original figure group data 211 Original figure group management data 212 Original figure data reference information 221 Original figure data 222 Original figure vertex coordinate data 301 Display figure group data 311 Level management data 312 Display Graphic vertex coordinate group data reference information 320 Display graphic management data Managed data 321 Display graphic management data 322 Display graphic vertex coordinate data reference information 331 Display graphic vertex coordinate group data 332 Display graphic vertex coordinate data 400 Consists of all vertices of a line shape graphic Figure 40 1 A figure composed of level 1 vertices of a line shape figure 402 A figure constituted of level 1 to level 2 vertices of a line shape figure 403 A figure constituted of level 1 to level 3 vertices of a line shape figure 500 A figure composed of all vertices of a surface shape figure 501 A figure constituted of level 1 vertices of a certain surface shape figure 502 A figure constituted of level 1 to level 2 vertices of a certain surface shape figure 503 From level 1 of a certain surface shape figure Figure composed of level 3 vertices

Claims (6)

A setting step for setting a plurality of display scale values for displaying the figure at a plurality of scales,
An acquisition step of acquiring original figure vertex coordinate data including information on a plurality of vertex coordinates constituting the figure from original figure data which is data constituting the figure;
For each of the plurality of display scale values, a display figure with a display scale value that is one scale smaller than each display scale value is constructed from all vertex coordinates constituting the display figure that is a figure corresponding to each display scale value. A first data generation step of generating display figure vertex coordinate group data which is set information of remaining vertex coordinates obtained by thinning out all vertex coordinates
And a second data generation step of generating display graphic management data which is information for associating the display graphic vertex coordinate group data generated for each display scale value with the display scale value. Graphic data generation method. Setting means for setting a plurality of display scale values for displaying the figure at a plurality of scales,
Obtaining means for obtaining original figure vertex coordinate data including information on a plurality of vertex coordinates constituting the figure from original figure data which is data constituting the figure;
For each of the plurality of display scale values, a display figure with a display scale value that is one scale smaller than each display scale value is constructed from all vertex coordinates constituting the display figure that is a figure corresponding to each display scale value. First data generation means for generating display figure vertex coordinate group data that is set information of remaining vertex coordinates obtained by thinning out all vertex coordinates to be
2nd data generation means which produces | generates the display figure management data which are the information for matching the said display figure vertex coordinate group data produced | generated for every said display scale value with the said display scale value, It is characterized by the above-mentioned. Graphic data generator. A setting step for setting one of a plurality of display scale values for displaying the figure at a plurality of scales;
For each of the plurality of display scale values, a display figure with a display scale value that is one scale smaller than each display scale value is constructed from all vertex coordinates constituting the display figure that is a figure corresponding to each display scale value. Display figure vertex coordinate group data that is a set of remaining vertex coordinates obtained by thinning out all vertex coordinates to be displayed, and display figure management data that is information for associating the display figure vertex coordinate group data with the display scale value; Is acquired from the recording medium and stored in a temporary storage memory, and
When the display scale value set in the setting step is smaller than the display scale value of the display graphic already displayed, it is acquired in the data acquisition step and stored in the temporary storage memory during the previous display process. A specifying step for specifying display graphic vertex coordinate group data required for display at the display scale value set in the setting step, among the display graphic vertex coordinate group data,
A display step of performing graphic display at the display scale value set in the setting step using the display graphic vertex coordinate data of the display graphic vertex coordinate group data specified in the specifying step. Graphic data display method. A setting step for setting one of a plurality of display scale values for displaying the figure at a plurality of scales;
For each of the plurality of display scale values, a display figure with a display scale value that is one scale smaller than each display scale value is constructed from all vertex coordinates constituting the display figure that is a figure corresponding to each display scale value. Display figure vertex coordinate group data that is a set of remaining vertex coordinates obtained by thinning out all vertex coordinates to be displayed, and display figure management data that is information for associating the display figure vertex coordinate group data with the display scale value; A first data acquisition step of acquiring from a recording medium and storing it in a temporary storage memory;
When the display scale value set in the setting step is larger than the display scale value of the display graphic already displayed, the temporary storage memory is acquired in the first data acquisition step during the previous display processing. A first specifying step of specifying display graphic vertex coordinate group data required for display at the display scale value set in the setting step among the display graphic vertex coordinate group data stored in
A second specifying step for specifying the display graphic vertex coordinate group data that is necessary for display at the display scale value set in the setting step and is not stored in the temporary storage memory;
A second data acquisition step of newly acquiring the display figure vertex coordinate group data specified in the second specification step from the external recording medium and storing the data in the temporary storage memory;
A display step of performing graphic display at the display scale value set in the setting step using the display graphic vertex coordinate data of the display graphic vertex coordinate group data specified in the first and second specifying steps. A graphic data display method comprising: and. Setting means for setting one of a plurality of display scale values for displaying a figure at a plurality of scales;
For each of the plurality of display scale values, a display figure with a display scale value that is one scale smaller than each display scale value is constructed from all vertex coordinates constituting the display figure that is a figure corresponding to each display scale value. Display figure vertex coordinate group data that is a set of remaining vertex coordinates obtained by thinning out all vertex coordinates to be displayed, and display figure management data that is information for associating the display figure vertex coordinate group data with the display scale value; Data acquisition means for acquiring from a recording medium and storing it in a temporary storage memory;
When the display scale value set by the setting means is smaller than the display scale value of the already displayed display figure, it is acquired by the data acquisition means during the previous display process and stored in the temporary storage memory. Specifying means for specifying display graphic vertex coordinate group data required for display at the display scale value set by the setting means among the displayed graphic vertex coordinate group data;
Display means for performing graphic display at the display scale value set by the setting means using the display graphic vertex coordinate data of the display graphic vertex coordinate group data specified by the specifying means. Graphic data display device. Setting means for setting one of a plurality of display scale values for displaying a figure at a plurality of scales;
For each of the plurality of display scale values, a display figure with a display scale value that is one scale smaller than each display scale value is constructed from all vertex coordinates constituting the display figure that is a figure corresponding to each display scale value. Display figure vertex coordinate group data that is a set of remaining vertex coordinates obtained by thinning out all vertex coordinates to be displayed, and display figure management data that is information for associating the display figure vertex coordinate group data with the display scale value; First data acquisition means for acquiring from a recording medium and storing it in a temporary storage memory;
When the display scale value set by the setting means is larger than the display scale value of the display graphic already displayed, the temporary storage memory is acquired by the first data acquisition means during the previous display processing. First specifying means for specifying display figure vertex coordinate group data required for display at the display scale value set by the setting means among the display figure vertex coordinate group data stored in
Second specifying means for specifying the display figure vertex coordinate group data that is necessary for display at the display scale value set by the setting means and is not stored in the temporary storage memory;
Second data acquisition means for newly acquiring the display figure vertex coordinate group data specified by the second specification means from the external recording medium and storing it in the temporary storage memory;
Display means for performing graphic display at the display scale value set by the setting means, using the display graphic vertex coordinate data of the display graphic vertex coordinate group data specified by the first and second specifying means. And a graphic data display device.