JP5531365B2 - Falling water line editing program and falling water line editing device - Google Patents

Description

  The present invention relates to a method for editing basin information using a computer. In particular, the present invention relates to a method for editing a waterfall line created by a computer program based on a digital elevation model (digital elevation mode, DEM).

  The channel network is a kind of basic data in hydrology. The falling water line is a directed line segment indicating the direction in which water on the ground surface flows. More precisely, it is data indicating the flow direction of surface water on a spatio-temporal scale that is the subject of hydrology, and is often expressed as a directed line segment on a map. If the falling water line is used, the basin can be easily obtained. In order to find the basin of a certain point, it is only necessary to follow the falling water line from that point in reverse (that is, in the upstream direction). Moreover, the flow direction and gradient required for the distributed runoff model (physical model that reproduces the water flow in the basin) can be easily calculated as the gradient of the ground surface elevation along the falling water line. In this way, the waterfall line is data widely used in hydrological research.

  The waterfall line is often created by a computer program (waterfall line creation program). The input data of the falling water line creation program is the elevation data of the ground surface. This is to utilize empirical knowledge that, on a hydrological spatio-temporal scale, the water flow direction coincides with the steepest descent direction of the ground surface (the steepest gradient direction). Non-Patent Document 1 provides a detailed comparison of major waterfall line creation programs and their processing procedures.

  The method of expressing the falling water line is not unique. For example, a method of expressing the direction of the falling water line, that is, the steepest gradient direction of the ground surface with an angle of 0 or more and less than 360 (Non-Patent Document 1) is conceivable. However, the most widely used method (referred to as D8 Method) is different from that, and the direction of the falling water line is expressed only in 8 directions (Non-Patent Document 2 and Non-Patent Document 3). In the D8 method, the ground surface is expressed by a set of rectangular small areas called cells. In this implementation, the elevation data of the ground surface used as input data takes an expression form called DEM (Digital Elevation Model). In DEM, the altitude of the ground surface is expressed by the altitude value given for each cell. Moreover, the falling water line which makes a certain cell a starting point is limited to what becomes a cell which one end point adjoins. Since there are eight adjacent cells, this limitation results in only eight waterfall lines. The waterfall line created in this way is used in hydrological research. For example, a “distributed runoff prediction system using national synthetic radar rainfall” disclosed in Patent Document 1 and a “flood prediction system” disclosed in Patent Document 2 can be cited. Furthermore, a method for dividing a basin in a client / server system via the Internet has been proposed (Non-Patent Document 4). Further, a method for generating a waterfall line in only eight directions by a method similar to the D8 method is disclosed in “Patent Document 3 Method for Creating Underground Elevation Model, Method for Dividing Wastewater Treatment Area, Method for Evaluating Wastewater Treatment Capacity and Apparatus”. .

JP 2009-8651 A JP 2007-11582 A JP 2007-204932 A JP 2009-163621 A

Tarboton, D. G .: A New Method for the Determination of Flow Directions and Upslope Areas in Grid Digital Elevation Models, Water Resources Research, Vol. 33, No. 2, pp. 309-319, 1997. O'Callaghan, J. F., and D. M. Mark: The extraction of drainage networks from digital elevation data, Computer Vision, Graphics, and Image Processing, Vol. 28, No. 3, pp. 323-344, 1984. Jenson, S. K., and J. O. Domingue: Extracting topographic structure from digital elevation data for geographic information system analysis, Photogrammetric Engineering & Remote Sensing, Vol. 54, No. 11, pp. 1593-1600, 1988. Choi, JY, and BA Engel: Real-Time watershed delineation system using Web-GIS, Journal of Computing in Civil Engineering, Vol. 17, No. 3, pp. 189-196, DOI: 10.1061 / (ASCE) 0887-3801 (2003) 17: 3 (189), 2003. Kobayashi, K., K. Takara, Y. Tachikawa and T. Sayama, Analysis of the Yuragawa River Flood by Typhoon No. 23 in October 2004 using a distributed rainfall-runoff model, Kyoto University Disaster Prevention Research Institute Annual Report, No. 49 C , 2006. Yamazaki, D., T. Oki, and S. Kanae, Deriving a global river network map and its sub-grid topographic characteristics from a fine-resolution flow direction map, Hydrology and Earth System Sciences, Vol. 13, Issue 11, pp 2241-2251, 2009. Freeman, T. G .: Calculating catchment area with divergent flow based on a regular grid, Computers & Geosciences, Vol. 17, Issue 3, pp. 413-422, DOI: 10.1016 / 0098-3004 (91) 90048-I, 1991. Quinn, P., K. Beven, P. Chevallier, and O. Planchon: The prediction of hillslope flow paths for distributed hydrological modeling using digital terrain models, Hydrological Processes, Vol. 5, Issue 1, pp. 59-79, DOI : 10.1002 / hyp.3360050106, 1991. Shrestha, R., Y. Tachikawa and K. Takara: A new method to define flow direction using grid digital elevation models, Annual Journal of Hydraulic Engineering, JSCE, Vol. 47, pp. 241-246, 2003.

  The waterfall line created by the waterfall line creation program may differ from the direction in which water actually flows. Such a problem becomes apparent when the map and the falling water line are displayed in an overlapping manner as in the invention “basin estimation program” already disclosed by the inventors (FIG. 6 of Patent Document 4). In general, a map shows a waterway, and when this and a falling water line are displayed in an overlapping manner, the difference in position and shape between the two becomes clear. On the other hand, the inventors thought that these problems occur only in a limited area, and therefore thought that an expert should directly edit data of a very limited cell. Actually, in Patent Document 1, “for a basin divided into meshes, a waterfall diagram is created based on a numerical map (1 km mesh average elevation, KS-273: basin boundary position, KS-272: flow path position), and It is assumed that such a way of thinking is general.

  However, in practice, it was found that the editing work was extremely difficult and the productivity was low. The waterfall line is data with a physical meaning of the flow direction of surface water on a hydrological spatio-temporal scale. On the other hand, if a human edits a waterfall line arbitrarily, the illegal waterfall line which contradicts this physical meaning may be produced | generated. An example of an unauthorized waterfall line is shown in FIG. 23 (FIG. 23 is an explanatory diagram showing an example of an unauthorized waterfall line).

  In FIG. 23A, when the cell 2301 is advanced in the direction of the falling water line, the original cell 2301 is restored. That is, the water that has flowed down into the cell 2301 continues to flow down forever without losing potential energy forever. Such a flow cannot be realized unless artificial equipment such as a pump is used.

  Another example is shown in FIG. In this example, water flows in the order of the cells 2311, 2314, 2313, and 2312. The falling water line coming out from the cell 2311 and the falling water line coming out from the cell 2313 intersect. Such a flow cannot be realized unless an artificial facility such as a siphon that realizes a three-dimensional intersection is used at the intersection of falling water lines.

  Yet another example is shown in FIG. In FIG. 23C, the altitude of the ground surface is the highest in the cell 2321, and the cells 2321, 2322, 2323, and 2324 in descending order, and the falling water line passes through the cells 2321, 2322, 2323, and 2324 in this order. This waterfall line seems to be correct because it flows downward. However, this waterfall line is illegal because it does not coincide with the steepest gradient direction on the ground surface.

  The correct falling water line in this topography is shown in FIG. Cells 2331, 2332, and 2333 are directly connected to 2334, respectively, by falling water lines. That is, water flowing out of the cells 2331, 2332, and 2333 flows directly into the cell 2334.

  In hydrology, an area consisting of about 10 million falling water lines may be targeted. For example, even if only 0.01% of the waterfall lines created by the waterfall line creation program are corrected, 1000 waterfall lines are edited. It is practically impossible to edit the waterfall line without generating such an illegal waterfall line, and even if possible, it is an extremely low productivity operation.

  The created falling water line is used for various hydrological processes, for example, a process for identifying an upstream of a certain point, a process for obtaining a basin area, or a process for obtaining an average gradient. However, there are cases where the above-described processing is hindered by the presence of the above-described fraud in the edited waterfall line. For example, when a falling water line as shown in FIG. 23 (a) is used, there arises a problem that the process of specifying the upstream does not end normally.

  The present invention has been made in view of this problem. An object of the present invention is to provide a computer program that automatically maintains the physical integrity of a waterfall while allowing a user to edit the waterfall.

The outline of the representative invention disclosed in the present application is as follows. That is, a waterfall line editing program for controlling a computer, wherein the computer includes a memory in which the waterfall line editing program is stored, and a processor that executes the program stored in the memory, and includes a plurality of cells. In the space, the altitude data indicating the altitude of each cell and the waterfall line data indicating the direction in which water flows from each cell are retained, and the waterfall line editing program stores the specified cell and the specified cell. A first procedure that receives a designation of a new waterfall starting from the point, a case where the designated waterfall and one or more already designated waterfalls circulate, and the designated waterfall when crossing the already specified drainage lines, a plurality of direction in which the designated drainage line is the starting point and the second procedure determines that fraud, the specified cell Of these, a direction other than the direction of the designated falling water line is set as an invalid direction, and further, among a plurality of directions starting from a cell adjacent to the designated cell, the direction intersects with the designated falling water line. By setting the direction as an invalid direction , based on the designated falling water line direction, a third procedure for determining an invalid direction in which the generation of a falling water line is prohibited for each cell, and on the basis of the elevation data , Causing the processor to execute a fourth procedure for changing the waterfall line data so that water flows downstream from each cell in a direction other than the invalid direction. In the second procedure, the designation is performed. If been drainage line is determined to be invalid, prior to the third procedure and the fourth procedure, for the designated cell, the designation of a new drainage line that starts the specified cell Kicking and wherein the to be executed by the re-said processor a first step.

  According to an embodiment of the present invention, it is possible to provide a computer program that automatically maintains the physical integrity of a waterfall line while allowing a user to edit the waterfall line. With this program, it will be possible to generate waterfall lines reflecting user knowledge in a short time and use them in hydrology.

It is a schematic block diagram which shows the structure of the computer system in embodiment of this invention. It is a sequence diagram which shows the interaction of the waterfall line edit program and hardware resource in embodiment of this invention. It is explanatory drawing which shows the state which started the edit in the replacement mode of GUI provided by the falling water line editing program in the first embodiment of the present invention. It is 1st explanatory drawing which shows the state which started the edit in the replacement mode of GUI provided by the falling water line edit program in the 1st Embodiment of this invention. It is the 2nd explanatory view showing the state where the edit in change mode of GUI provided by the falling water line edit program in a 1st embodiment of the present invention is continued. It is explanatory drawing which shows the state which has decided the edit content in the replacement mode of GUI provided by the falling water line edit program in the 1st Embodiment of this invention. It is explanatory drawing which shows the state which is editing the topography in the replacement mode of GUI provided by the falling water line editing program in the first embodiment of the present invention. It is explanatory drawing which shows the state which displayed the waterfall line after editing in the replacement mode of GUI which the waterfall line edit program in the 1st Embodiment of this invention provides. It is explanatory drawing which shows the state which is editing the topography in the addition mode of GUI which the waterfall line edit program in the 1st Embodiment of this invention provides. It is explanatory drawing which shows the state which displayed the falling water line after editing the topography in the addition mode of GUI provided by the falling water line editing program in the 1st Embodiment of this invention. It is explanatory drawing which shows the state which is editing the topography in the deletion mode of GUI provided by the falling water line editing program in the first embodiment of the present invention. It is explanatory drawing which shows the state which displayed the falling water line after editing the topography in deletion mode of GUI provided by the falling water line editing program in the 1st Embodiment of this invention. It is a package figure which shows the functional module structure of the falling water line edit program of the 1st Embodiment of this invention. It is explanatory drawing which shows the data structure of the cell of the 1st Embodiment of this invention. It is a sequence diagram which shows the detail of interaction with the waterfall line edit program and hardware resource in the process of designation | designated of the waterfall line edit content of the 1st Embodiment of this invention. It is a flowchart which shows the algorithm of the designation | designated process of the falling water line edit content in the 1st Embodiment of this invention. It is a sequence diagram which shows the detail of interaction with the falling water line edit program and hardware resource in the process of designation | designated of the topography edit content of the 1st Embodiment of this invention. It is a flowchart which shows the algorithm of the process of designation | designated of the topography edit content of the 1st Embodiment of this invention. It is explanatory drawing which shows the state in edit in the replacement mode of GUI provided by the falling water line edit program in the 2nd Embodiment of this invention. It is a flowchart which shows the algorithm of the designation | designated process of the falling water line edit content in the 2nd Embodiment of this invention. It is explanatory drawing which shows the state in edit in the case of adding the one part area | region outside a basin as a basin of GUI provided by the falling water line edit program in the 2nd Embodiment of this invention. It is explanatory drawing which shows the state in edit in the case of deleting the partial area | region of a basin as GUI outside which the falling water line edit program in the 2nd Embodiment of this invention provides. It is explanatory drawing which shows the example of an unauthorized waterfall line

  First, the outline of the present invention will be described.

  The present invention is based on the principle that the inventors have found that actual flows are classified into the following three types.

  Flow 1: A flow that can be expressed as a falling water line.

  Flow 2: A flow that can be expressed as a flow connecting cells.

  Flow 3: A flow that cannot be expressed as a flow connecting cells (for example, a flow having a smaller spatial scale than the cells, a flow that is not uniform in the depth direction).

  Clearly, stream 2 includes stream 1. A specific example of the flow 2 is shown in FIG. The flow shown in FIGS. 23A to 23D is all expressed as a flow connecting cells, and is clearly flow 2. On the other hand, the correct flow as the falling water line is only FIG. 23D as described above, and the falling water line (flow 1) is a part of the flow 2.

  Of the flow 2, the flow in FIGS. 23 (c) and 23 (d) can be expressed by the same physical law (flow flowing in the downward direction of the altitude) as the flow line in the water channel connecting the cells. This is because, even if the "water flowing direction" of the waterfall line is determined by the altitude of the surrounding cells as in the waterfall line, or determined by the wall of the waterway as in the waterway, it flows in the downward direction of the altitude. This is because there is no difference in the nature of the flow. This is clear from the fact that a water channel that is sufficiently wide compared to a cell can be represented by a falling water line. As suggested by this, the reason why the flow in FIGS. 23C and 23D cannot be expressed as a falling water line is difficult to understand intuitively. 23 (a) and 23 (b) cannot be expressed by changing the cell size, and the expression is greatly different from the need for a dedicated physical model (such as a pump or siphon).

  On the other hand, the reason that the user thinks "the actual flow and the falling water line are different" is that the water channel described on the map is implicitly expressed as a water channel that connects cells implicitly, and the water channel and the falling water line generation program are created. It is thought that it is judged that the waterfall line is very different. Accordingly, the inventors have thought that if the waterfall line and the water channel are allowed to coexist, a “waterfall line” that is considered to be correct for the user can be realized.

  The falling water line flows in the direction of the steepest slope, and the water channel flows along the center line of the water channel. However, it is common that both flow down in the downward gradient direction. Therefore, in order to allow these flows to coexist, it is only necessary to change the terrain so as to allow a falling water line that flows in a direction other than the steepest gradient direction and a downward gradient direction along the channel center line. However, in this operation, the slope connecting the downfall line and the upstream end of the waterway and the slope connecting the downstream end of the waterway and the downfall line so that the upstream end and downfall line of the waterway and the downstream end and downfall line are connected consistently. Both are possible only when the slope is downhill.

  Based on the above principle, the falling water line editing program of the present invention devised by the inventors is composed of the following steps 1 to 3.

  Step 1: A cell and a flow direction are designated from the user. In this step, the user only has to input a cell serving as a water channel and its flow direction as a falling water line editing instruction.

  Step 2: Determine the elevation of the designated cell based on the direction of flow of the designated cell. However, when two types of elevation are given to one cell, or when the designated cell is an upstream cell and the elevation is higher than the upstream cell, or If it is a specified cell and the downstream cell is not specified and the altitude is lower than that of the downstream cell, the terrain editing instruction is regarded as an instruction that cannot be changed, and the process is interrupted. Alternatively, the process returns to step 1 to request the user to re-enter the water channel position.

  Step 3: Update the falling water line. In this step, it is only necessary to generate a waterfall using the cell received in step 1 and the flow direction and the topography determined in step 2 and to overwrite the existing waterfall.

  The present invention is directed to stream 1 and stream 2. It is clear that the flow 3 cannot be expressed using cells. However, the flow 3 can be dealt with by combining a known technique and the present invention. As a method for expressing the flow 1 and the flow 3, for example, Non-Patent Document 5 uses a method of connecting a specific cell of a model representing the flow 1 to a cell of another model (river model). Non-Patent Document 6 proposes a method of expressing two or more flows in one cell. Since these methods can be used in combination with a model using a falling water line, they can be used in combination with the present invention.

  Hereinafter, embodiments of the falling water line editing program will be described using two examples. The first embodiment is suitable for editing each falling water line, and the second embodiment is suitable for editing a plurality of falling water lines in a wider area. Since both are based on the same principle, there is no contradiction even if both functions are provided in one program. Therefore, a program having both functions may be created and the user may select either of these embodiments.

  For convenience of explanation, it is assumed that the falling water line is generated by the D8 method in the embodiment. Therefore, there is one falling water line coming out from each cell. The falling water line is displayed as a line segment or an arrow connecting the centers of the cells. However, the present invention is not only applicable to the D8 method, but can be applied to a case where a falling line is generated using elevation data in cells and the falling line is expressed as a directed line segment connecting cells. Examples of waterfall line generation methods other than the waterfall line generation method D8 method described in the present embodiment include the multiple flow direction method shown in Non-Patent Document 7 or Non-Patent Document 8, and the Ranked flow tendency shown in Non-Patent Document 9. method. In these methods, unlike the D8 method, there are one or more falling water lines coming out of each cell. Further, as a method that is not the falling water line display method described in the present embodiment, there is a method of connecting cell edges or vertices shown in Non-Patent Document 4 (Fig. 4d).

<First Embodiment>
DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, a first embodiment of the invention will be described with reference to the accompanying drawings.

  FIG. 1 is a schematic block diagram showing the configuration of a computer system according to an embodiment of the present invention.

  The computer system of the present embodiment is configured by a PC (Personal Computer) 100. The PC 100 includes an input / output unit 110. The input / output unit 110 includes an input unit including a keyboard 111 and a mouse 112, and an output unit including a display 113. The user can input a command from the input unit and check the result from the output unit.

  The PC 100 further includes a memory 120 and a CPU (Central Processing Unit) 130. A falling water line editing program 141 is developed in the memory 120. This falling water line creation program 141 is composed of instructions to the CPU. The CPU 130 performs calculation, access to an HDD (Hard Disk Drive) 190, exchange of information with the input / output unit 110, and the like in accordance with the instructions of the falling water line creation program 141. In the following description, the processing executed by the falling water line editing program 141 is actually executed by the CPU 130 in accordance with instructions described in the basin extraction program 141.

  The HDD 190 stores altitude data 191, waterfall line data 192, and map data 193, and the waterfall line editing program 141 can read and write these data. The HDD 190 may be incorporated in the PC 100, connected to the outside of the PC 100, or connected to another device that can be accessed from the PC 100 via a network.

  The altitude data 191 is data generally called a digital elevation model (DEM). That is, the altitude data 191 is information describing the position of the cell and the altitude of the ground surface in the cell. Since a cell assigned to a location is unique, a unique identification number (ID) can be assigned to the cell based on the location information of the cell. Further, in the altitude data 191, an altitude value is stored in the land area, and a value indicating the sea area is stored in the sea area. The sea area is a water area without an outlet, that is, an ocean and a closed lake area (a lake without a water outlet).

  The waterfall line data 192 is information describing the position of the cell and the attributes of the waterfall line in the cell, like the altitude data 191. The attributes of the falling water line are direction, gradient, and the like. Furthermore, this attribute may include the analysis result of the falling water line data such as the number of cells upstream from the cell and the ID of the most downstream cell. This data is created in advance using the falling water line generation program. As the falling water line generation program, for example, the invention “basin estimation program” disclosed in Patent Document 4 by the inventors can be used.

  The map data 193 may be information that can be used as a determination material for the user to edit the falling water line. Information suitable as the map data 193 includes a topographical map in which positions of rivers and the like are described.

  FIG. 2 is a sequence diagram showing the interaction between the waterfall line editing program 141 and hardware resources executed by the PC 100.

  The falling water line editing program 141 is activated on the PC 100. The falling water line editing program 141 reads the falling water line data 192 from the HDD 190 (step 201). The falling water line editing program 141 that has read the data outputs a GUI (Graphical User Interface) composed of the window 300 to the display 113 (step 202). Using this GUI, the falling water line editing program 141 receives an edit mode designation (step 203). This step can be omitted. When this step is executed, the user's operation is restricted to prevent the user's erroneous operation. Further, using the GUI, the falling water line editing program 141 receives a falling water line editing instruction from the user (step 204). The falling water line editing program 141 determines whether or not the instructed falling water line is illegal, and receives this instruction only when it is not illegal.

  Subsequently, the falling water line editing program 141 converts the falling water line editing instruction by the user into the terrain editing instruction (step 205). In this step, the user may be queried for details of the conversion. In the present embodiment (first embodiment), a case where an inquiry is made will be described. In another embodiment (second embodiment), a case where no inquiry is made will be explained. The falling water line editing program 141 edits the terrain according to the terrain editing instruction (step 206), and generates a falling water line based on the edited terrain (step 207).

  In this step 207, a downfall line in the downward gradient direction is generated using the downfall line generator 1322 (see FIG. 13). As the falling water line generation unit 1322, for example, the invention “basin estimation program” disclosed by the inventors in Patent Document 4 can be used. In step 207, the waterfall line generating unit 1322 generates a waterfall line so as not to generate a waterfall line that returns (that is, circulates) to the waterfall line designated by the user and a waterfall line that crosses the waterfall line designated by the user. .

  Further, as will be described in detail later, in the present embodiment, when an invalid direction is determined for a certain cell, a falling line is generated so as to coincide with a downward gradient direction among directions that are not invalid directions. For example, the “basin estimation program” described above creates a falling water line that matches the steepest slope direction of the downward slope, but when the “basin estimation program” is used in this embodiment, the steepest of the directions that are not invalid directions. A falling water line that matches the gradient direction is created.

  The falling water line editing program 141 may display the generated falling water line on the GUI (step 208) and allow the user to confirm that the falling water line is as intended. Alternatively, a command for saving data may be received from the user, and the altitude data 191 and the waterfall line data 192 may be written (steps 209 and 210). As a result, the altitude data 191 and the falling water line data 192 are updated.

  Note that the falling water line editing program desirably causes the user to select “replacement”, “addition”, or “deletion” in step 203.

  When “replacement” is selected, the user-editable waterfall line is restricted within the basin. In this case, since the basin boundary is not changed, the processing in step 207 may be performed only in the basin (that is, in the basin specified by the falling water line data 192 at the time of reading in step 201). Specifically, in step 207, the falling water line generating unit 1322 identifies the steepest gradient direction only for the cells in the basin, and creates the falling water line based on the specified direction, but the steepest gradient direction for the cells outside the basin. Do not execute processing to identify

  When “Add” is selected, the start point of the falling water line that can be edited by the user is limited to be outside the basin. In this case, since the basin is expanded, the processing in step 207 needs to be performed outside the basin. That is, in step 207, the falling water line generating unit 1322 needs to specify the steepest gradient direction not only for the cells in the basin but also for the cells outside the basin, and create the falling line based on the direction.

  When “Delete” is selected, the end point of the falling water line that can be edited by the user is restricted to be outside the basin. In this case, since the basin is reduced, as in the case of “replacement”, the processing in step 207 need only be performed within the basin.

  The important points in the sequence of the falling water line editing program 141 are the reception of the falling water line editing instruction (step 204), the conversion of the falling water line editing instruction into the editing instruction such as terrain (step 205), and the change of the altitude data (step). 206) and processing in the order of change of the falling water line data (step 207). As long as processing is performed in this order, other sequences can be changed. For example, it is possible to return to step 203 again after step 210 and continue a new editing operation.

  The transition of the GUI regarding step 203 to step 208 is shown in FIGS.

  FIG. 3 is an explanatory diagram showing a state where editing in the replacement mode of the GUI provided by the falling water line editing program 141 according to the first embodiment of the present invention is started (step 204).

  3 includes a window 300 displayed in a predetermined area of the display 113, and receives input from the keyboard 111 and the mouse 112. The window 300 preferably includes at least a falling water line display unit 310, and further includes an editing command input unit 320 and a topographic section display unit 330.

  The falling water line display unit 310 displays the falling water lines (for example, the falling water line 311) included in the falling water line data 192 read at least in step 201. All these falling water lines reach the downstream end cell 343. That is, the cell displayed on the falling water line display unit 310 in this state is the basin of the cell 343. In order to clarify this, it is desirable to represent the basin boundary as a thick line segment 362. In order to indicate the position of the cell, a cell side (frame line) may be indicated like a line segment 361. In the example of FIG. 3, each rectangular area divided in a lattice shape by a frame line such as a line segment 361 is a cell (for example, a cell 341).

  The falling water line display unit 310 has a function of allowing the user to specify a falling water line to be edited. In the present embodiment, the movement of the mouse 112 is detected, the mouse pointer 301 is moved, and an operation (for example, left click) of the mouse 112 is detected to allow the user to designate a falling water line to be edited. In order to convey the user's operation result to the user in an easy-to-understand manner, it is desirable to display the designated waterfall line 311 with a thick line and / or display the icon 302 at the end point of the designated waterfall line 311.

  Furthermore, it is desirable that the waterfall line display unit 310 detects a right click of the mouse 112 and causes a user interface (context menu) for the user to notify the waterfall line editing program 141 of the end of editing. Details thereof will be described with reference to FIG. The edit command input unit 320 includes a drop-down list 321 that allows the user to designate an “edit mode”. The drop-down list 321 allows the user to select one of “replacement”, “addition”, and “deletion”.

  The terrain cross-section display unit 330 is a GUI for supporting user operations in the processing for specifying the details of the falling water line editing process (step 204) and converting the editing instructions for the falling water line into the editing instructions for the terrain (step 205). The topographic section display unit 330 includes a vertical axis 331 and a horizontal axis 332. As will be described later, the cells along the horizontal axis are arranged in a certain order, and their elevations are shown on the vertical axis. Furthermore, the topographic section display unit 330 includes an interface that allows the user to change the elevation value. As described above, the window 300 has a function of designating at least one falling water line.

  Further, the map data 193 may be displayed on the falling water line display unit 310 of the window 300. This makes it easy for the user to edit the falling water line. In order to implement this function, the falling water line editing program 141 may read the falling water line data 192 and the map data 193 in step 201.

  In the present embodiment, step 203 is realized by allowing the user to select any one of “replacement”, “addition”, and “deletion” from the editing command input unit 320.

  First, the case where the user selects the “replacement” mode will be described with reference to FIGS. 3 to 8.

  The user selects one waterfall line in the waterfall display section 310. FIG. 3 shows a state immediately after the falling water line 311 is selected. An icon 302 is displayed at the end point of the selected falling water line, and the icon moves when the mouse pointer 301 is moved. This icon 302 is displayed only at the center of the cell closest to the mouse pointer 301 among the eight cells adjacent to the cell 341 (the start cell of the falling water line 311). When the user left-clicks the mouse 112, it can be replaced with the cell where the end point of the falling water line is clicked. For example, when the user places the mouse pointer 301 on the cell 342 and left-clicks, the screen transitions to FIG.

  FIG. 4 is a first explanatory diagram showing a state (step 204) in which the GUI provided by the falling water line editing program 141 according to the first embodiment of the present invention is being edited in the replacement mode.

  Cells 441 and 442 in FIG. 4 correspond to cells 341 and 342 in FIG. 3, respectively.

  The waterfall line 311 in FIG. 3 is replaced with the waterfall line 411 in FIG. 4. Furthermore, the falling water line 412 located downstream of the falling water line 411 is displayed with a bold line. The topographic sections along these falling water lines 411 and 412, that is, the elevations of the cells 441 to 443 are shown in the topographic section display section 430. Falling lines 411 to 412 correspond to arrows 431 to 432, and cells 441 to 443 correspond to rectangles 451 to 453, respectively.

  The elevation of the rightmost cell 453 is lower than the elevation of the leftmost cell 451 of the topographical section display unit 430. In this state, that is, in a state where the altitude of any cell located downstream of the cell (441) where the user starts specifying is lower than the altitude of the cell, the user confirms the editing content or continues editing. You can choose either to do. When the user places the mouse pointer 401 on the cell 444 and left-clicks, it is determined that the user has selected to continue editing, and the screen transitions to FIG.

  FIG. 5 is a second explanatory diagram illustrating a state (step 204) in which editing in the replacement mode of the GUI provided by the falling water line editing program 141 according to the first embodiment of the present invention is continued.

  Cells 541, 542, and 543 in FIG. 5 correspond to cells 441, 442, and 444 in FIG. 4, respectively.

  The waterfall line 412 of FIG. 4 is replaced with the waterfall line 512 of FIG. As in FIG. 4, the falling water lines 513 and 514 downstream of the falling water line 512 are displayed in bold lines. The topographic section along the falling water lines 511 to 514, that is, the elevations of the cells 541 to 545 are shown in the topographic section display unit 530. Falling lines 511 to 514 correspond to arrows 531 to 534, and cells 541 to 545 correspond to rectangles 551 to 555, respectively.

  The altitude of the right end cell 555 is lower than the altitude of the left end cell 551 of the topographic section display unit 530. Again, in this state, the user can choose to either confirm this editing content or continue editing. When the user operates the mouse 112 (for example, right click), the screen transitions to FIG.

  FIG. 6 is an explanatory diagram showing a state (step 204) where the editing content in the replacement mode of the GUI provided by the falling water line editing program 141 according to the first embodiment of the present invention is fixed.

  When the user right-clicks the mouse 112, a context menu 601 written “Confirm” and “Cancel” appears. By selecting “Confirm”, the user can confirm the edited contents, and click “Cancel”. By selecting, the context menu 601 can be hidden. When the user selects “OK” in this state, the falling water line editing program 141 proceeds to step 205, and the screen transitions to FIG.

  FIG. 7 is an explanatory diagram showing a state (step 205) in which the terrain in the replacement mode of the GUI provided by the falling water line editing program 141 according to the first embodiment of the present invention is edited.

  Cells 741 to 745 in FIG. 7 correspond to cells 541 to 545 in FIG. 5, respectively.

  When the GUI transitions to this state, the user can operate the confirmation button 725 and the topographic section display unit 730 of the editing command input unit 720. A solid line rectangle (rectangles 751 to 755) and a broken line rectangle (rectangles 756 to 758) are drawn on the topographic section display unit 730. The broken-line rectangle represents the altitude of the cells 742 to 744 as in FIGS. The solid line rectangle has a downward slope from the leftmost cell 751 of the topographic section display unit 730 toward the rightmost cell 755 (that is, the elevation of the cell at the end point of each falling water line is lower than the elevation of the cell at the start point). B) represents the automatically calculated elevation.

  If this automatically calculated altitude is different from the user's intention, the user can edit it. When the user brings the mouse pointer close to the upper side of the solid rectangle, the mouse pointer changes to an arrow icon 701, indicating that the upper side of the rectangle can be changed. In addition, if the slope is downward from the cell 751 toward the cell 755, the confirm button 725 is operable. In other words, step 205 can be completed when all the slopes are from the cell (741) in which the user has started the specification to the cell 745 in which the user has specified the specification.

  In this state, when the user operates the confirm button 725 (for example, the mouse 112 is operated by placing the mouse pointer on the confirm button), the falling water line editing program 141 completes step 205 and executes steps 206 to 208. Transitions to FIG.

  FIG. 8 is an explanatory diagram showing a state (step 208) in which the waterfall line after editing in the replacement mode of the GUI provided by the waterfall line editing program 141 according to the first embodiment of the present invention is displayed.

  Cells 842 to 844 in FIG. 8 correspond to cells 742 to 744 in FIG. 7, respectively.

  In step 206 (altitude data change), the altitudes of cells 842 to 844 change. Therefore, under the influence of this change, the falling water line which ends these cells changes. On the other hand, the falling water line starting from these cells is changed as specified by the user in step 204. In the example of FIG. 8, the falling water lines 746 to 747 in FIG. 7 are automatically replaced with the falling water lines 846 to 847, respectively.

  The user refers to the falling water line display unit 810, confirms that the falling water line is as intended, and issues a command for saving data as necessary. In response to this, the falling water line editing program 141 executes steps 209 to 210. The result of the editing work is stored in the HDD 190 by step 209 (altitude data 191 writing) and step 210 (waterfall line data 192 writing).

  In the terrain editing process of FIG. 7, the user convenience can be further improved by omitting the editing of the elevation of the start point (cell 751) and the end point (cell 755). This is because the fact that the user has selected these cells can be interpreted that the user has determined that the waterfall line upstream from the start point (cell 751) and the waterfall line downstream from the start point (cell 755) are correct.

  Second, the case where the user selects the “add” mode in step 203 (designation of edit mode) will be described with reference to FIGS.

  FIG. 9 is an explanatory diagram showing a state (step 205) in which the terrain in the addition mode of the GUI provided by the falling water line editing program 141 according to the first embodiment of the present invention is being edited.

  FIG. 9 shows a state in which the process of specifying the waterfall line editing process (step 204) has been performed, that is, a state in which the content of editing the waterfall line has been confirmed by the user through the context menu 601 as shown in FIG. In step 204, the user designates a falling water line that starts from a cell outside the basin and ends at a cell inside the basin. In FIG. 9, a falling water line 911 starting from the cell 941 and ending at the cell 942 is designated by the user. Further, as in FIG. 4, the falling water line 912 downstream of the falling water line 911 is indicated by a bold line.

  The topographic section along the falling water lines 911 to 912, that is, the elevations of the cells 941 to 943 are shown in the topographic section display unit 930. Falling lines 911 to 912 correspond to arrows 931 to 932, and cells 941 to 943 correspond to rectangles 951 to 953, respectively. The altitude of the right end cell 953 is lower than the altitude of the left end cell 951 of the topographic section display unit 930. Thus, step 204 can be completed when the altitude of any cell located downstream of the cell (941) that the user has started to specify is lower than the altitude. Further, step 205 can be completed when all of the cells from the cell (941) in which the user has started the specification to the cell 943 in which the user has made the specification are descending.

  Subsequently, when the user operates the confirm button 925, the falling water line editing program 141 executes steps 206 to 208, and the screen transitions to FIG.

  FIG. 10 is an explanatory diagram showing a state (step 208) of displaying the falling water line after editing the terrain in the addition mode of the GUI provided by the falling water line editing program 141 in the first embodiment of the present invention.

  In step 206 (altitude data change), the altitude of the cell 1042 changes. Therefore, under the influence of this change, the falling water line which ends these cells changes. In the example of FIG. 10, waterfall lines 1011 to 1014 are added.

  Third, the case where the user selects the “delete” mode in step 203 (designation of edit mode) will be described with reference to FIGS.

  FIG. 11 is an explanatory diagram showing a state (step 205) in which the terrain in the deletion mode of the GUI provided by the falling water line editing program 141 according to the first embodiment of the present invention is being edited.

  Like FIG. 9, this FIG. 11 shows a state where the process of specifying the waterfall line editing content (step 204) has been performed, that is, a state where the editing content of the waterfall line has been confirmed by the user through the context menu 601 as shown in FIG. Show. However, contrary to the “add” mode, in this “delete” mode, in step 204, the user designates a falling water line starting from a cell in the basin and ending in a cell outside the basin. Here, “inside the basin” means inside the basin surrounded by the basin boundary 1162, and “outside the basin” means outside the basin. The basin boundary 1162 corresponds to the basin boundary 362 in FIG. 3, but the basin boundary 362 has been changed to the basin boundary 1162 by editing the “addition” mode described above.

  In FIG. 11, a falling water line 1112 starting from the cell 1142 and ending at the cell 1143 is added by the user. As in FIG. 4, the falling water line 1113 downstream of the falling water line 1112 is indicated by a bold line.

  The topographic section along the falling water lines 1111 to 1113, that is, the elevations of the cells 1141 to 1144 are shown in the topographic section display unit 1130. Falling lines 1111 to 1113 correspond to arrows 1131 to 1133, and cells 1141 to 1144 correspond to rectangles 1151 to 1154, respectively. The altitude of the right end cell 1154 is lower than the altitude of the left end cell 1151 of the topographic section display unit 1130.

  Note that step 204 in FIG. 11 was performed as follows. The cell that the user starts to designate is 1141, and the user designates the cell 1142 in the basin as the end point of the falling water line 1111 starting from this cell. At this point, step 204 is not allowed to complete. This is because, at this time, the water flowing out from the cell 1141 cannot flow into a cell outside the basin whose elevation is lower than that of the cell 1141 via the falling water line designated by the user. For this reason, the falling water line editing program 141 accepts an operation for designating the end point of the falling water line starting from the cell 1142 without causing the “confirm” menu of the context menu 601 to appear.

  Subsequently, the user designates the end point of the falling water line starting from the cell 1142 as the cell 1143. At this stage, the falling water line 1113 is displayed as a bold line. The falling water line 1113 indicates the steepest gradient direction at the time when the cell 1143 is designated (that is, the time before the altitude of the cell 1143 is edited). The altitude of the cell 1144 that is the end point cell of the falling water line 1113 is lower than the altitude of the cell 1141, and the cell 1144 is a cell outside the basin (that is, a cell outside the basin boundary 1162). In this case, the cell 1141 can be deleted from the basin indicated by the basin boundary 362 by changing the elevation of each cell to match the user's designation. Thus, step 204 is permitted to be completed when cell 1143 is designated.

  When the user selects the “confirm” menu of the context menu 601, the falling water line editing program 141 completes step 204. Subsequently, when the user operates the confirm button 1125, the falling water line editing program 141 executes steps 206 to 208, and the screen transitions to FIG.

  FIG. 12 is an explanatory diagram showing a state (step 208) in which the falling line after editing the topography in the deletion mode of the GUI provided by the falling line editing program 141 according to the first embodiment of the present invention is displayed.

  The cells 1241 to 1243 in FIG. 12 correspond to the cells 1141 to 1143 in FIG. 11, respectively. Moreover, the waterfall lines 1211 to 1213 in FIG. 12 correspond to the waterfall lines 1111 to 1113 in FIG. 11, respectively.

  In step 206 (altitude data change), the altitudes of the cells 1242 to 1243 change. Therefore, under the influence of this change, the falling water line which ends these cells changes. In the example of FIG. 12, the falling water line 1214 is deleted. Also, the falling water lines 1211 to 1213 designated by the user are also deleted from the basin. Accordingly, the watershed boundary is also changed from the watershed boundary 362 in FIG. 3 to the watershed boundary 1262 in FIG.

  FIG. 13 is a package diagram showing the functional module configuration of the falling water line editing program 141 according to the first embodiment of this invention.

  The falling water line editing program 141 includes two modules, a window management module 1310 and a logic management module 1320. The window management module 1310 includes a window frame management unit 1311, a falling water line display unit 1312, an edit command input unit 1313, and a topographic section display unit 1314. On the other hand, the logic management module 1320 includes a waterfall line editing unit 1321, a waterfall line generation unit 1322, and a file input / output unit 1323.

  As for the GUI of the waterfall line editing program 141 shown in FIG. 3, the window 300 is managed by the window frame management unit 1311, and the waterfall line display unit 310, the editing command input unit 320, and the topographic cross section display unit 330 inside the window 300 The display unit 1312, the edit command input unit 1313, and the topographical section display unit 1314 manage each. Further, in the sequence of the waterfall line editing program 141 shown in FIG. 2, the reading of the waterfall line data 192 (step 201), the writing of the altitude data 191 (step 209), and the writing of the waterfall line data 192 (step 210) are mainly performed. The file input / output unit 1323 manages the file. Receiving the falling water line editing instruction (step 204), converting the falling water line editing instruction into a terrain editing instruction (step 205), and changing elevation data (step 206) are mainly managed by the falling water line editing unit 1321. The change of the waterfall line data (step 207) is mainly managed by the waterfall line generator 1322. As the falling water line generation unit 1322, for example, the invention “basin estimation program” disclosed by the inventors in Patent Document 4 can be used.

  FIG. 14 is an explanatory diagram illustrating a cell data structure according to the first embodiment of this invention.

  Table 1400 in FIG. 14 shows cell type data. The cell type (class name Cell) is a class having four member variables of Glev, IsTheBasin, LowerDirection, and InvalidDirections. Glev is a floating-point type and retains elevation. IsTheBasin is a Boolean type and holds true if the cell is in a basin, false otherwise. LowerDirection is an enumeration type, and holds either of the directions in which water flows (eight types) or a total of nine types of values indicating that water does not flow from the cell.

  InvalidDirections is an enumerated type that represents a bit field. As with LowerDirection, InvalidDirections can hold a total of nine values indicating the direction in which water flows from the cell (eight types) or no water flowing from the cell. However, unlike LowerDirection, these nine types are true or false, respectively. Holds the value of.

  The basin boundary 362 is created at the boundary between the cells in the basin and the cells outside the basin with reference to IsTheBasin.

  InvalidDirections indicates the direction of the invalid waterfall line, that is, the direction in which the generation of the waterfall line is prohibited. For example, the value in the direction across the falling water line created by the user is true. This means that the direction crossing the waterfall created by the user is an invalid direction, that is, generation of a waterfall in that direction is prohibited. Similarly, when the direction of the waterfall line starting from a certain cell is designated by the user, the value of InvalidDirections in a direction other than the designated direction is true for that cell. In step 207, the falling water line generation unit 1322 refers to this InvalidDirections so as not to generate a falling water line in the direction corresponding to the value true. This cell type data can be expanded and may have other variables.

  Details of steps 204 and 205 in the processing sequence (FIG. 2) for realizing these screen transitions will be described below. Since the processing contents of the steps other than these are obvious from the screen transition, the description is omitted.

  FIG. 15 is a sequence diagram illustrating details of the interaction between the waterfall line editing program 141 and the hardware resource in the processing of specifying the waterfall line editing content (step 204) according to the first embodiment of this invention.

  In step 204, the falling water line editing program 141 accepts designation of the start cell (that is, the start cell of the target falling water line) from the user (step 1501). The user designates a start cell through the input / output unit 110 (step 1502). At this time, if the editing mode designated in step 203 is “replacement” or “deletion”, only the cells in the basin can be designated. On the other hand, in the case of “add”, only cells outside the basin can be specified.

  Subsequently, the falling water line editing program 141 accepts designation of a passing cell (step 1503). A passing cell is a cell that is an end point of a falling water line that starts from a start cell. The screen state in FIG. 3 corresponds to this step 1502.

  The user designates a passing cell through the input / output unit 110 (step 1504). The falling water line input in this manner is classified into three types: “can be converted into terrain editing instruction”, “cannot be converted into terrain editing instruction”, and “illegal”. These determination methods will be described with reference to FIG.

  If it is determined that the input waterfall line is “illegal”, the input value is rejected and the process returns to step 1503. In other cases, the falling water line editing program 141 converts the falling water line editing instruction into a terrain editing instruction (step 1505). In step 1505, the altitude data 191 is read (step 1506). In addition, the processing result of step 1505 is displayed as a topographic sectional view on the input / output unit 110 (step 1507).

  The falling water line editing program 141 accepts a confirmation instruction or further passing cell designation when “can be converted into terrain editing instruction”, and accepts further passing cell designation when “cannot be converted into terrain editing instruction” (step) 1508). The screen states in FIGS. 4 and 5 correspond to this step 1508.

  The user designates a confirmation instruction or a passing cell through the input / output unit 110 (step 1509). The screen in FIG. 6 is in a state where a confirmation instruction is input in step 1509.

  When the user designates a passing cell through the input / output unit 110, the process returns to Step 1505 (Step 1510). In the case of a confirmation instruction, step 204 is ended.

  FIG. 16 is a flowchart showing an algorithm of processing for designating the content of the falling water line editing (step 204) in the first embodiment of the present invention.

  The relationship between FIG. 15 and FIG. 16 is as follows: Step 1501 to Step 1601, Step 1503 to Step 1602-1603, Step 1505-1506 to Step 1604-1610, Step 1508 to Step 1611-1612 Correspond.

  The falling water line editing program 141 accepts designation of the start cell from the user (step 1601). The falling water line editing program 141 calls a function WaitUserInput that receives an input from the user, and stores the value input by the user in theCell. The falling water line editing program 141 adds this value theCell as the first element of the empty cell array Cells having no element (step 1602).

  However, if the editing mode is “Replace” and theCell is outside the basin, or if the editing mode is “Add” and theCell is in the basin, or if the editing mode is “Delete” and theCell is outside the basin, The line editing program 141 rejects the input from the user and returns to step 1601.

  Subsequently, the falling water line editing program 141 accepts designation of a passing cell from the user (step 1603), and stores the value input by the user in theCell. This is the falling water line in the direction connecting the last element of the cell array Cells and theCell (for example, when the cell 441 in FIG. 4 is specified in step 1601 and the cell 442 is specified in step 1603, the falling line 411). Is specified by the user.

  However, the falling water line editing program 141 determines whether or not the input falling water line is illegal, and if it is incorrect, the value input by the user is not stored in theCell. Specifically, in the following case, the falling water line editing program 141 determines that the falling water line designated by the user is an “illegal” falling water line and rejects the input from the user (step 1604); (1) the value of theCell Is already stored in the cell array Cells, or (2) a new waterfall line intersects an existing user-specified waterfall line.

  The fact that the value of theCell is already stored in the cell array Cells means that a new waterfall line input and a waterfall line already input form a loop. That is, when it is assumed that all the falling water lines shown in FIG. 23 are user-specified water falling lines, FIG. 23A shows the case of (1) above, and FIG. 23B shows the case of (2) above. It corresponds to.

  If the user-specified waterfall line is not an "invalid" waterfall line, the user-specified waterfall line is either a waterfall line that can be converted to a terrain editing instruction or a waterfall line that cannot be converted to a terrain editing instruction. It is. In this case, the falling water line editing program 141 adds the value theCell input by the user to the cell array Cells (step 1605). At this time, the waterfall editing program 141 removes the direction connecting the cell and theCell (that is, the direction of the waterfall specified by the user) to InvalidDirections of the last element before adding the cell array Cells (referred to as a variable cell). Set 7 directions. Furthermore, the falling water line editing program 141 sets the direction intersecting the direction connecting the cell and theCell to InvalidDirections of the cell adjacent to the cell.

  Note that InvalidDirections set in this way are referred to by the falling water line generator 1322 in step 207. In step 207, the falling water line generation unit 1322 generates a falling water line by the steepest gradient method, for example, as disclosed in Patent Document 4. At this time, the falling water line generation unit 1322 refers to InvalidDirections of each cell and generates a falling water line in the direction of the steepest gradient among directions other than the invalid direction. Thereby, the waterfall line designated by the user is reliably generated in step 207, and the generation of the waterfall line intersecting with the waterfall line designated by the user is prohibited.

  Subsequently, the falling water line editing program 141 substitutes the last element of the cell array Cells, that is, the cell downstream of theCell, in the variable cell (step 1606). The downstream cell of theCell is an end cell of a falling water line that starts from theCell, and theCell and this downstream cell are adjacent to each other. For example, if theCell is the cell 442 in FIG. 4, the downstream cell is the cell 443. This downstream cell is determined by the steepest gradient method, for example. However, when an invalid direction (InvalidDirections) has already been defined for theCell, a falling water line with the steepest gradient direction among the directions excluding the invalid direction is defined. The same applies to step 1607 described later.

  When the start point of the waterfall line is outside the basin, the downstream cell does not exist in the waterfall data 192. In this case, the falling water line editing program 141 may obtain a downstream cell from the topographic data 191, or may substitute theCell into a variable cell and proceed to Step 1610.

  After the end of step 1606, the falling water line editing program 141 initializes the cell array LowerCells (that is, deletes all elements included in the cell array LowerCells). Subsequently, the falling water line editing program 141 adds the downstream cell searched in Step 1606 to the cell array LowerCells (Step 1608).

  Subsequently, the falling water line editing program 141 determines whether or not the falling water line that reaches the downstream cell added in Step 1608 is “cannot be converted into a terrain editing instruction” (Step 1609). Specifically, when the variable cell is included in the cell array LowerCells, the falling line designated by the user and the falling line downstream thereof form a loop (see FIG. 23A). In such a case, and when the falling water line reaching the downstream cell added in step 1608 intersects the falling water line already designated by the user or the downstream falling water line (see FIG. 23B), the user The input of “cannot be converted into terrain editing instructions”. In this case, the process returns to step 1603, and the falling water line editing program 141 receives an input of a further passing cell from the user.

  When variable cell is not included in this cell array LowerCells (step 1609), and when the elevation of variable cell is lower than the elevation of the start cell (step 1610), the input from the user is “can be converted into terrain editing instruction” It is. In this case, the process of the falling water line editing program 141 proceeds to step 1611. On the other hand, if the elevation of the variable cell is not lower than the elevation of the start cell, it cannot be determined whether the input from the user is "can be converted to terrain editing instructions" or "cannot be converted to terrain editing instructions" The falling water line editing program 141 searches for the downstream cell of the variable cell, stores the searched downstream cell in the variable cell (step 1607), and then executes step 1608 again.

  In the example of FIG. 7, cell 741 is a start cell specified by the user, cells 742 and 743 are passing cells specified by the user, and cells 744 and 745 are searched downstream cells. The waterfall line from the start cell to the passing cell and the waterfall line from the passing cell to the passing cell are user-specified waterfall lines.

  In the example of FIG. 7, since the altitude of the cell 743 that is the end point of the last falling water line specified by the user is higher than the altitude of the cell 741 that is the starting point of the first falling water line, the input instruction is It was necessary to search downstream of the cell 743 to determine whether or not it can be converted into an instruction. However, if the cells 744 and 745 are also designated as passing cells by the user in the example of FIG. 7, since the altitude of the cell 745 is lower than the altitude of the cell 741, the downfall line downstream of the cell 745 has already been designated. There is no possibility of going back (ie, forming a loop) or intersecting the already specified waterfall. For this reason, it is not necessary to search the downstream cell of the cell 745.

  However, if there is no downstream cell because the variable cell is outside the basin in step 1607, the falling water line editing program 141 may obtain the downstream cell from the topographic data 191 or may proceed to step 1603. .

  When the input from the user is “can be converted into a terrain editing instruction”, the falling water line editing program 141 receives an input of a further passing cell or a confirmation instruction from the user, and stores the user's input in a variable theCell (step 1611). ). When the variable theCell is an input of a further passing cell, the process returns to step 1603, and when the variable theCell is a confirmation instruction, the step 204 is ended (step 1612).

  FIG. 17 is a sequence diagram illustrating details of the interaction between the waterfall line editing program 141 and the hardware resources in the processing for specifying the terrain editing content (step 205) according to the first embodiment of this invention.

  The falling water line editing program 141 temporarily determines the cell altitude (step 1701). The provisional determination method will be described with reference to FIG.

  The falling water line editing program 141 displays the result of provisional determination in step 1701 as a topographic sectional view on the input / output unit 110 (step 1702), and accepts a confirmation instruction from the user or designation of altitude (step 1703). The screen states in FIGS. 7, 9, and 11 correspond to this step 1703.

  The user performs a confirmation instruction or an altitude designation through the input / output unit 110 (step 1704). When the user designates the altitude (step 1705), the process returns to step 1703 (step 1706), and in the case of a confirmation instruction, step 205 is ended.

  FIG. 18 is a flowchart showing an algorithm for specifying the terrain editing content (step 205) according to the first embodiment of this invention.

  The relationship between FIG. 17 and FIG. 18 is as follows; Step 1701 corresponds to Steps 1801-1804, Step 1703 corresponds to Step 1805, Step 1705 corresponds to Step 1806, and Step 1706 corresponds to Steps 1807-1808.

  The falling water line editing program 141 adds the cell array LowerCells created in step 1608 of FIG. 16 to the cell array Cells (step 1801).

  Subsequently, the falling water line editing program 141 calculates the average slope AveSlope of these cells (step 1802). The value of this AveSlope is the elevation Cells.Front.Glev of the first element (cell 751 in the example of FIG. 7) and the elevation Cells.Last.Glev of the last element (cell 755 in the example of FIG. 7) of the cell array Cells. Is divided by the total length of the falling water lines.

  Subsequently, the falling water line editing program 141 obtains a temporary value of the cell elevation using this AveSlope (step 1803). The temporary value of the elevation Cell [i] .Glev of the i-th cell of the cell array Cells is AveSlope * Distance (Cells [i-1], Cells [i]) + Cells [i-1] .Glev. However, Distance (cell0, cell1) is a function that returns the distance between cell0 and cell1. In addition, for the first element (Cells [0], that is, Cells.Front) and the last element (Cells.Last), a temporary value of altitude is not obtained. Thereby, the gradient between adjacent cells through which the waterfall line passes from the first element to the last element becomes constant. In the example of FIG. 7, the altitudes of the cells 752 to 754 are changed so that the directions of the falling water lines from the cells 751 to 755 coincide with the downward gradient direction, and the gradients thereof become constant.

  The temporary value of the altitude may be obtained by another method as long as all elements of the cell array Cells have a downward gradient. Therefore, even if all the falling water lines designated by the user do not coincide with the steepest gradient direction, the altitude value of the cell does not have to be changed if they coincide with the downward gradient direction (ie, step 205 and 206 may be omitted).

  Subsequently, the falling water line editing program 141 sets a flag IsValidUserChannel indicating that the gradient between all the elements of the cell array Cells is true (step 1804). This makes it possible to determine the temporary altitude value as the altitude of each cell. That is, when the flag IsValidUserChannel becomes true, a confirmation button (for example, the confirmation button 725 in FIG. 7) is displayed, and it becomes possible to accept the user's operation for that.

  Subsequently, the falling water line editing program 141 displays a temporary value of the altitude on the input / output unit 110 and receives an instruction from the user (step 1805). The falling water line editing program 141 accepts an elevation change or confirmation instruction when the flag IsValidUserChannel is true, and accepts an elevation change when the flag IsValidUserChannel is false. User instructions are stored in the variable Command.

  When the variable Command is an instruction to change the altitude (step 1806), the falling water line editing program 141 reflects the instruction on the altitude and calculates the gradient between all elements of the cell array Cells (step 1807). The falling water line editing program 141 sets the flag ValidUserChannel to true when the gradient between all elements is a downward gradient. On the other hand, if the gradient between any of the elements is not a downward gradient (that is, an upward gradient), the falling water line editing program 141 sets the flag ValidUserChannel to false and returns to step 1805 (step 1808). In step 1806, when the variable Command is an instruction to change the altitude (that is, when the confirmation button is operated), step 205 is ended.

  By editing the altitude as described above, the direction of the falling water line specified by the user always matches the downward gradient direction. However, the falling water line designated by the user does not always coincide with the direction of the steepest slope. Therefore, if the waterfall line generation in step 207 after the elevation data is changed in step 206 without restricting the direction of the waterfall line, the waterfall line specified by the user may not be generated. For this reason, as already described in the present embodiment, the direction other than the direction specified by the user is registered as an invalid direction for the cell specified by the user, and the falling water line generation unit 1322 generates a falling water line in an invalid direction. do not do. Thereby, the waterfall line designated by the user is maintained after the waterfall line generation in step 207. However, this also means that in this embodiment, the generation of waterfall lines as shown in FIG.

  However, in the present embodiment, as already described, the generation of the waterfall line as shown in FIGS. 23A and 23B is reliably prevented, and further, the waterfall line in the upward gradient direction is not generated. For this reason, the falling water line produced | generated by this embodiment can be used without trouble in various hydrological processes, for example, calculation of a basin area.

  As described above, according to the first embodiment of the present invention, it is possible to provide a computer program that automatically maintains the physical integrity of the waterfall line while allowing the user to edit the waterfall line. it can. As a result, a falling water line reflecting the knowledge of the user, such as the actual shape of the water channel, can be generated in a short time and used for hydrology.

<Second Embodiment>
Hereinafter, a second embodiment of the present invention will be described with reference to the accompanying drawings. The schematic block diagram (FIG. 1) which shows the structure of the computer system in embodiment of this invention, and the sequence diagram (FIG. 2) which shows the interaction of the waterfall line editing program 141 and hardware resource which are performed by PC100 are shown. The same as described in the first embodiment. However, the details of the processing of steps 203, 204 and 205 are different. Steps 201 to 208 will be described with reference to FIGS. 19 to 22 while referring to these differences.

  FIG. 19 is an explanatory diagram showing a state during editing in the replacement mode of the GUI provided by the falling water line editing program 141 according to the second embodiment of the present invention (step 204).

  A window 1900 shown in FIG. 19 provides a function similar to that of the window 300 shown in FIG. However, the waterfall line display unit 310 of the window 300 displays all the waterfall lines, whereas the waterfall line display unit 1910 of the window 1900 displays a waterfall line (for example, a waterfall line) of a cell having a basin area larger than a preset value. Line 1921), and basin boundary 1922 are displayed. In general, since the falling water line of a cell having a larger basin area is more important, only the important falling water line can be set as the editing target. Further, the edit command input unit 320 and the topographic section display unit 330 provided in the window 300 are not provided in the window 1900. In this embodiment, only “replacement” is used for editing the falling water line. Also, the terrain editing instruction from the user is not accepted, and the temporary elevation calculated in step 1803 is always adopted. Therefore, step 203 using the edit command input unit 320 and step 205 using the topographic section display unit 330 are processed without making an inquiry to the user.

  This window 1900 is output to the display 113 after the waterfall line editing program 141 reads the waterfall line data 192 from the HDD 190 (step 201) (step 202). The editing mode is always “replacement” (step 203). Using this window 1900, the user edits the falling water line (step 204). It should be noted that at the time before editing by the user is started, the falling water line 1911 indicated by a thick solid line and the icons 1912 and 1913 at both ends thereof are not displayed in the window 1900.

  First, the falling water line editing program 141 causes the user to designate an arbitrary cell in the basin as a starting cell (starting point of the falling water line input by the user), and displays an icon 1912 at the center of the starting cell. Subsequently, the falling water line editing program 141 allows the user to designate an arbitrary cell that is in the basin and has an altitude lower than the starting cell as an end cell (that is, the end point of the falling water line input by the user). When the end cell is designated, an icon 1913 is displayed at the center of the end cell, and a falling water line 1911 is displayed in a cell through which a line segment connecting the start cell and the end cell passes.

  In this state, the user can determine the waterfall line 1911 or change the cell through which the waterfall line 1911 passes. In the former case, the user operates the confirm button 1931. In the latter case, the user edits the falling water line 1911 using a general function necessary for polyline editing. However, in polyline editing, control points are limited only to cells.

  For example, when it is desired to change the shape of the generated waterfall line 1911, the mouse 112 is used to click one cell constituting the waterfall line 1911. Then, a control point of the polyline is added at the position of the clicked cell, and the mouse cursor changes like a mouse cursor 1901 to display that the control point can be moved. The user can move this control point to another cell. When the user operates the confirm button 1931, step 204 ends.

  Subsequently, the editing instruction for the falling water line is converted into an editing instruction for terrain or the like (step 205), the altitude data is changed (step 206), and the falling water data is changed (step 207). In this process, the cells that should be targeted by the falling water line generation unit 1322 are only within the watershed indicated by the waterfall line data 192 at the time of reading in step 201, and outside the watershed can be excluded. This is because the basin boundary is not changed in the “replacement”.

  By these processes, the falling water line is changed. The changed waterfall line is displayed on the waterfall line display unit 1910 (step 208). The waterfall line in FIG. 19 is changed to the waterfall line in FIG. The waterfall lines (waterfall lines 1911 and 2111) designated by the user are created as designated by the user. On the other hand, the shape of the surrounding falling water line is changed by being affected by the change of the altitude data. For example, the falling water line 1921 in FIG. 19 is changed to a falling water line 2121 in FIG.

  The window 1900 can also provide an edit command input unit 320 and a topographic section display unit 330. In that case, the operation method of the edit command input unit 320 and the topographical section display unit 330 is the same as that of the first embodiment.

  When the edit mode is “add”, in the window 1900, any one cell outside the basin is designated as the start cell, and any one cell that is within the basin and whose elevation is lower than the start cell is designated as the end cell. The

  When the edit mode is “Delete”, in the window 1900, any one cell in the basin is designated as the start cell, and any one cell that is outside the basin and whose elevation is lower than the start cell is designated as the end cell. The

  As in the first embodiment, in both the “add” and “delete” editing modes, the processing other than step 204 is the same as in the “replacement” case.

  FIG. 20 is a flowchart showing an algorithm for processing for specifying the content of the falling water line editing (step 204) in the second embodiment of the present invention.

  First, the falling water line editing program 141 accepts designation of a start cell by the user (step 2001). The falling water line editing program 141 calls a function WaitUserInput that receives an input from the user, and stores the value input by the user in theCell. This value theCell is added as the first element of the empty cell array Cells having no element (step 2002). However, if theCell is outside the basin, the input from the user is rejected and the process returns to step 2001.

  Subsequently, the falling water line editing program 141 receives the designation of the end cell from the user (step 2003), and stores the value input by the user in theCell. However, if theCell is outside the basin, or the elevation of theCell is higher than the elevation of the start cell Cells.First.Glev, the falling water line editing program 141 converts the input from the user to “illegal” or “terrain editing instruction” Reject as "impossible" waterfall (step 2004). In this case, the falling water line editing program 141 returns to step 2003 to accept the designation of the end cell from the user again.

  When theCell is in the basin and the elevation of theCell is lower than the elevation of the start cell Cells.First.Glev, the falling water line editing program 141 determines that the input from the user can be “converted into a terrain editing instruction”. Then, the value theCell input by the user is added to the cell array CtrlCells (step 2005).

  Subsequently, the falling water line editing program 141 converts a line segment that sequentially connects all elements of the cell array CtrlCells into a cell array (step 2006). As a conversion method, a general method for converting a line segment into a cell such as Bresenham's line algorithm may be used. In this way, a cell array Cells is created in which the first element is the start cell and the last element is the end cell.

  Subsequently, the falling water line editing program 141 displays the falling water line on the created cell array, receives the designation of the passing cell from the user, and stores the user input in the variable theCell (step 2007). If the variable theCell is a confirmation instruction, that is, an operation of the confirmation button 1931, the falling water line editing program 141 ends this step 204 (step 2008).

  When the variable theCell is a passing cell designation, the falling water line editing program 141 determines whether the condition that the user-specified water line draws a loop or the user-specified water lines intersect each other is true. (Step 2009). Whether or not the user-specified waterfall line draws a loop may be determined by the same method as in step 1807 in FIG. When the condition of step 2009 is false (that is, when the user-specified waterfall line does not draw a loop and the user-specified waterfall lines do not intersect with each other), the waterfall line editing program 141 arranges the cell in a cell array. Insert in CtrlCell (step 2010) and return to step 2006. If the condition is true, discard the cell and return to step 2006.

  The process of adding and deleting waterfall lines in the present embodiment is realized by performing a process of replacing waterfall lines after the process of adding or deleting watershed boundaries.

  FIG. 21 is an explanatory diagram showing a state during editing when a partial area outside the basin is added as a basin of the GUI provided by the falling water line editing program 141 according to the second embodiment of the present invention.

  The GUI shown in FIG. 21 provides a function of extending a line segment 2122 indicating a basin boundary outside the basin using the mouse cursor 2101. A line segment 2123 is a new watershed boundary expanded in this way.

  FIG. 22 is an explanatory diagram illustrating a state during editing in the case where the GUI provided by the falling water line editing program 141 according to the second embodiment of the present invention is deleted when a partial area of the basin is deleted.

  Similar to FIG. 21, the GUI shown in FIG. 22 provides a function of reducing a line segment 2222 indicating the basin boundary into the basin using the mouse cursor 2201. A line segment 2223 is a new watershed boundary reduced in this way.

  When the user operates the confirm button 2231 after moving the line segment indicating the basin boundary by the operation shown in FIG. 21 and FIG. 22, the falling water line editing program 141 creates a new one for the cell in contact with the new basin boundary. Set the direction across the basin boundary to “invalid direction” (ie, add a value to InvalidDirections indicating such “invalid direction”). Also, for cells that touch the erased basin boundary, cancel the “invalid direction” setting for the direction across the erased basin boundary (that is, delete the value indicating such “invalid direction” from InvalidDirections). To do).

  Thereafter, the waterfall line data is changed (step 207) based on the cell data. In the process of changing the falling water line data (step 207), the falling water line crossing the watershed boundary is not generated. After changing the watershed boundary in this way, the user edits the waterfall line in the watershed by the operation of replacing the waterfall line described with reference to FIG.

  According to the second embodiment of the present invention described above, it is possible to edit the falling water line as in the first embodiment using a relatively simple user interface.

  As described above, according to the present invention, it is possible to provide a program computer program that automatically maintains the physical consistency of the waterfall line while allowing the user to edit the waterfall line. If the user finds a location where the location and shape of the waterway and the waterfall shown on the map differ from each other, the user can edit the waterfall to fit the waterway shown on the map. become able to.

100 PC
141 Falling Line Editing Program 191 Elevation Data 192 Falling Line Data 1911 Falling Line 1912 Entered by User Start Cell (Starting Point of Falling Line Entered by User)
1913 End cell (end point of falling water line entered by cell user)
1921 A new waterfall generated based on user input information based on the user's input information based on the user's input data.

Claims (14)

A drainage line editing program for controlling a computer,
The computer
A memory for storing the waterfall editing program; and a processor for executing the program stored in the memory;
In a space including a plurality of cells, the altitude data indicating the altitude of each cell, and waterfall line data indicating the direction in which water flows from each cell,
The falling water line editing program is
A first procedure for receiving designation of the cell and designation of a new waterfall line starting from the designated cell;
The designated waterfall when the designated waterfall circulates and one or more already designated waterfalls circulate, and when the designated waterfall intersects the already designated waterfall. A second procedure for determining that the line is incorrect ;
Among a plurality of directions starting from the specified cell, a direction other than the direction of the specified falling water line is set as an invalid direction, and a plurality of cells starting from a cell adjacent to the specified cell are set. By setting a direction that intersects the designated waterfall line as an invalid direction among the directions, an invalid direction in which the generation of the waterfall line is prohibited for each cell based on the direction of the designated waterfall line is set. A third procedure to determine;
Based on the altitude data, the processor executes the fourth procedure of changing the waterfall line data so that water flows downstream from each cell in a direction other than the invalid direction,
In the second procedure, when it is determined that the designated falling water line is invalid, the designated cell is set as a start point for the designated cell before the third procedure and the fourth procedure. A falling water line editing program which causes the processor to execute again the first procedure which receives designation of a new falling water line to be performed.   The falling water line editing program changes a height of at least one cell of the start point or the end point so that an altitude of an end cell of the designated falling line is lower than an altitude of a start point cell, The falling water line editing program according to claim 1, wherein the processor is executed before the fourth procedure.   A plurality of continuous waterfall lines are specified in the first procedure, and an altitude of an end cell of the last waterfall line of the plurality of continuous waterfall lines is an elevation of the first waterfall line of the plurality of continuous waterfall lines. When the elevation is lower than the start point cell, the fifth step includes the first fall line among the cells through which the fall line from the start point cell of the first fall line to the end cell of the last fall line passes. The method includes a step of changing the altitude of the cells excluding the start cell and the end cell of the trailing waterfall line so that the direction of each waterfall line coincides with the downward slope direction. The falling water line editing program described in. In the first procedure, one falling line or a plurality of continuous falling lines is designated, and the altitude of the cell at the end of the falling line at the end of the one falling line or the plurality of continuous falling lines is the above-described one. If it is higher than the elevation of the cell at the start of the first waterfall line or the first waterfall line of the plurality of waterfall lines, the waterfall editing program
Causing the processor to execute a sixth procedure for searching for a cell downstream from the cell at the end point until a cell having an altitude lower than the cell at the start point is reached;
If one or more waterfalls leading to the searched downstream cell and one or more waterfalls already specified circulate, and a waterfall leading to the searched downstream cell already specified The first procedure is executed again to receive the designation of a new waterfall line starting from the cell at the start point before the fourth procedure,
In the fifth procedure, among the cells through which a falling line from the start point cell to the searched end cell passes, the elevations of the cells excluding the start point cell and the searched end cell are set to 4. The falling water line editing program according to claim 3, further comprising a procedure for changing the direction of the falling water line so as to coincide with the direction of the downward slope. The computer further holds information indicating whether each cell is a cell in a basin;
When the designated cell is a cell in the basin and the cell at the end point of the designated waterfall line starting from the designated cell is a cell in the basin, the waterfall line editing program 2. The falling water line editing program according to claim 1, wherein the processor is caused to execute the fourth procedure for only cells in the basin. The computer further holds information indicating whether each cell is a cell in a basin;
When the designated cell is a cell in the basin, and the cell at the end point of the designated waterfall line starting from the designated cell is a cell outside the watershed, the waterfall line editing program 2. The falling water line editing program according to claim 1, wherein the processor is caused to execute the fourth procedure for only cells in the basin. The computer further holds information indicating whether each cell is a cell in a basin;
The specified cell is said basin outside the cell, and wherein when the cell of the end point of the specified drainage line is a cell in said basin, said drainage line editing program that starts the specified cell 2. The falling water line editing program according to claim 1, wherein the processor executes the fourth procedure for cells in the basin and cells outside the basin. 2. The falling water line editing program according to claim 1, wherein the first procedure includes a procedure of receiving designation of a new falling water line starting from a cell at an end point of the designated falling water line. The plurality of cells includes a first cell and a second cell;
2. The first procedure includes a procedure of receiving designation of a first cell, a second cell, and a plurality of continuous new waterfall lines from the first cell to the second cell. The falling water line editing program described in. The falling water line editing program further causes the processor to execute a seventh step of receiving designation of a basin boundary position,
  The said 3rd procedure further includes the procedure which sets the direction which cross | intersects the boundary of the said specified basin as an invalid direction about the said cell adjacent to the boundary of the said specified basin. The described falling water line editing program. A memory for storing a program; and a processor for executing the program stored in the memory,
  In a space including a plurality of cells, the altitude data indicating the altitude of each cell, and the waterfall line data indicating the direction in which water flows from each cell,
  In response to the designation of the cell and the designation of a new waterfall line starting from the designated cell,
  The designated waterfall when the designated waterfall circulates and one or more already designated waterfalls circulate, and when the designated waterfall intersects the already designated waterfall. Determine that the line is incorrect,
  Among a plurality of directions starting from the specified cell, a direction other than the direction of the specified falling water line is set as an invalid direction, and a plurality of cells starting from a cell adjacent to the specified cell are set. By setting a direction that intersects the designated waterfall line as an invalid direction among the directions, an invalid direction in which the generation of the waterfall line is prohibited for each cell based on the direction of the designated waterfall line is set. Decide
  Based on the elevation data, the waterfall line data is changed so that water flows in the downstream direction from the cells other than the invalid direction,
  When it is determined that the designated waterfall line is invalid, the designation of a new waterfall line starting from the designated cell is received again before the invalid direction is determined and the waterfall line data is changed. A falling water line editing device characterized by that. The waterfall line editing device, before changing the waterfall line data, at least one cell of the start point or the end point so that the altitude of the end cell of the designated waterfall line is lower than the altitude of the cell of the start point. 12. The falling water line editing apparatus according to claim 11, wherein the altitude of the waterfall is changed. The waterfall editing device is configured such that a plurality of continuous waterfall lines are designated, and an elevation of a cell at the end of the waterfall line at the end of the plurality of waterfall lines is an initial waterfall of the plurality of continuous waterfall lines. If the elevation is lower than the cell at the start point of the line, the cell at the start point of the first falling line out of the cells that pass through the falling line from the start point cell of the first falling line to the end point cell of the last falling line The falling line editing device according to claim 12, wherein the altitude of the cells excluding the cell at the end point of the trailing falling line is changed so that the direction of each falling line coincides with the direction of the downward slope. . The falling water line editing device
  A single falling line or a plurality of continuous falling lines is designated, and an elevation of a cell at the end of the falling line at the end of the one falling line or the plurality of continuous falling lines is the one falling line or the If it is higher than the elevation of the cell at the start of the first falling water line of the plurality of continuous waterfalls, the downstream cell of the cell at the end point is searched until reaching a cell whose elevation is lower than the cell at the start point,
  If one or more waterfalls leading to the searched downstream cell and one or more waterfalls already specified circulate, and a waterfall leading to the searched downstream cell already specified If the waterfall line is crossed, before the change of the waterfall line data, again, the designation of a new waterfall line starting from the start point cell,
  Among the cells through which the falling water line from the starting point cell to the searched end cell passes, the altitude of the cell excluding the starting point cell and the searched end cell is reduced in the direction of each falling line. The falling water line editing apparatus according to claim 13, wherein the waterfall line editing apparatus is changed so as to coincide with the direction of the gradient.

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