Apparatus and method for topographic processing

• US 5,444,618 A
• Filed: 07/24/1992
• Issued: 08/22/1995
• Est. Priority Date: 07/25/1991
• Status: Expired due to Term

• Current Assignee: Hitachi Information & Control Systems Incorporated, Hitachi, Ltd.
• Original Assignee: Hitachi Information & Control Systems Incorporated, Hitachi, Ltd.
• Inventors: Seki, Shinji, Ibusuki, Makoto, Nomoto, Yasuei
• Primary Examiner(s): NOT, DEFINED
• Assistant Examiner(s): Hazard, J. L.
• Application Number:
  US07/918,592
• Time in Patent Office: 1,124 Days
• Field of Search: 364/420, 364/443, 364/457, 382/56
• US Class Current: 702/5
• CPC Class Codes: G06T 17/05 Geographic models

Abstract

For topographic processing, a plurality of maps are stored, the maps being of different scales and therefore being based on different amounts of map data. The user selects a map of appropriate scale, and can then select a part, for example a line, on which appropriate analysis is to be made, such as obtaining a cross section based on contour data of the map. The map data corresponding to the selected part of the map is investigated and, where it does not meet an appropriate criterion, the data of a part of a map of different scale is investigated, the part of the two maps corresponding to the same region. Hence information can be derived which meets the appropriate criterion. Thus, when obtaining a cross section, if the amount of data for a region of a map is insufficient for a satisfactory cross section to be obtained, the data of the same region of a map of larger scale is analyzed, so that a satisfactory cross section can be achieved. The processing is also applicable to the investigation of lines of sight, using the map data.

Claims

1. A computer apparatus for topographic processing comprising:

storage means for storing a plurality of different topographic map data relating to a same region of a map;

selection means for selecting a first one of said different topographic map data;

analysis means for selecting partial data of said first one of said different topographic map data relating to a part of the same region, analyzing said partial data of said first one of said different topographic map data in order to determine whether a density of said partial data of said first one of said different topographic map data is more than a predetermined density threshold, and generating the partial data of said first one of said different topographic map data when said density is more than said predetermined density threshold and generating other partial data of a second one of said different topographic map data when said density is not more than said predetermined threshold; and

display means for displaying a contour of altitude relating to the topographic map data in the same region of the map based on either one of the partial data and the other partial data guarantee by said analysis means.

2. A computer apparatus according to claim 1, wherein said analysis means generates further information which is provided in addition to the displayed topographic data, and said display means displays said further information.

3. A computer apparatus according to claim 2, wherein said display means simultaneously displays said contour of altitude relating to the topographic map data and at least a part of said further information.

4. An apparatus according to claim 1, wherein said plurality of maps are of respectively different scales, and said first one of said maps has a smaller scale than said second one of said maps.

5. A computer apparatus according to claim 1, further including means for generating interpolation contour information corresponding to said part of said first one of said plurality of different topographic map data, and for analyzing said interpolation contour information to generate additional information which is provided in addition to the displayed topographic data, said display means displays said additional information.

6. A computer apparatus for topographic processing comprising:

storage means for storing a plurality of different topographic map data relating to a same region of a map;

selection means for selecting a first one of said different topographic map data;

analysis means for selecting partial data of said first one of said different topographic map data relating to a part of the same region, analyzing a part of the same region data to determine whether a density of said partial data of said first one of said different topographic map data is more than a predetermined density threshold, and generating the partial data of said first one of said different topographic map data when said density is more than said predetermined density threshold and generating other partial data of a second one of said different topographic map data when said density is not more than said predetermined threshold; and

display means for displaying said information;

wherein said analysis means divides said part of said first map into a plurality of sub-regions, and determines whether said sub-regions have a density of the map data more than said predetermined threshold, such that said part of said second one of said plurality of maps corresponds to any one of said plurality of sub-regions for which said density of the map data is more than said predetermined density threshold.

7. A computer apparatus for topographic processing comprising:

means for storing a plurality of different topographic map data relating to a same region of a map;

means for selecting a first map of said different topographic map data;

means for selecting a part of said first one of said different topographic map data relating to a part of the same region, dividing said part of said first map of said different topographic map data into a plurality of sub-regions, and investigating the density of map data of said plurality of sub-regions of said part of said first map of said different topographic map data;

automatic investigation means, responsive to when the density of map data of any one of said plurality of sub-regions is not higher than a predetermined density threshold, for automatically investigating the map data of a part of a second map of said different topographic map data, said part of said second map corresponding to said any one of said plurality of sub-regions of said first map of said different topographic map data; and

means for generating a display of information combining data from said part of said second one of said different topographic map data and said plurality of sub-regions of said first one of said different topographic map data other than any one of said plurality of sub-regions for which the density of map data of said any one of said plurality of sub-regions is not higher than said predetermined density threshold.

8. A computer apparatus for topographic processing comprising:

means for storing a plurality of different topographic map data relating to a same region of a map, the map data of said plurality of different topographic map data having respectively different densities of topographic information and including contour data defining a plurality of contours;

means for defining a line on a selected first one of said different topographic map data for contour information display;

means for defining a plurality of sub-regions of said line;

means for investigating said sub-regions of said line to determine which of said sub-regions have contour data higher than a predetermined density threshold;

means for investigating part of a second one of said different topographic map data, said part corresponding to any of said sub-regions of said line for which said contour data is lower than said predetermined density threshold;

means for generating contour information corresponding to said line by analysis based on data of those sub-regions of said first of said different topographic map data intersected by said line for which the contour data is higher than said predetermined threshold and contour data of said part of said second one of said different topographic map data; and

means for displaying said contour information.

9. A computer apparatus for topographic processing, comprising:

means for storing at least one different topographic map data relating to a same region of a map, said different topographic map data including contour data;

means for defining a line on said at least one different topographic map for contour information display;

means for defining a plurality of sub-regions of said line;

means for investigating said sub-regions of said line to determine which of said sub-regions have contour information higher than a predetermined density threshold;

means for generating interpolation contour information corresponding to said line for those of said sub-regions for which the contour information is not higher than said predetermined threshold;

means for generating contour information corresponding to said line by analysis based on said interpolation contour information and contour information from each of said sub-regions of said line; and

means for displaying said contour information.

10. A method of topographic processing, said method comprising the steps of:

storing a plurality of different topographic map data relating to a same region of a map;

selecting a first one of said different topographic map data;

selecting partial data of said first one of said different topographic map data relating to a part of the same region;

analyzing said partial data of said first one of said different topographic map data in order to determine whether a density of said partial data of said first one of said different topographic map data is more than a predetermined density threshold;

generating the partial data of said first one of said different topographic map data when said density is more than said predetermined density threshold; and

generating other partial data of a second one of said different topographic map data when said density is not more than said predetermined density threshold;

wherein the analyzing step includes the sub-steps of;

dividing said partial data of said first one of said different topographic map data into a plurality of sub-regions and determining whether the density of map data of each sub-region is more than said predetermined density threshold; and

wherein said partial data of said second one of said different topographic map data corresponds to any of said plurality of sub-regions for which the density of the map data is more than said predetermined density threshold.

11. A method according to claim 10, wherein said partial data of said first one of said different topographic map data is a line.

12. A method according to claim 11, wherein said map data includes contour data defining a plurality of contours, and said predetermined threshold corresponds to a minimum number of intersections of contours with said line for each sub-region.

13. A method of topographic processing comprising:

storing a plurality of different map data relating to a same region of a map;

selecting a part of a first one of said different topographic map data;

dividing said part of said first one of said different topographic map data into a plurality of sub-regions;

investigating the map data of each of said sub-regions to determine whether the density of said map data of each sub-region is higher than a predetermined density threshold;

for each sub-region for which the density of said map data is not higher than said predetermined density threshold, investigating the map data of a corresponding part of a second one of said different topographic map data; and

generating a display of information combining data from said part of said second one of said different topographic map data, and said plurality of sub-regions of said first one of said different topographic map data other than any one of said plurality of sub-regions for which the density of the map data is not higher than said predetermined density threshold.

14. A method of topographic processing, comprising:

storing a plurality of different topographic map data, the different topographic map data being of respectively different densities of topographic information and including contour information defining a plurality of contours;

defining a line on a first one of said different topographic map data for contour information display;

defining a plurality of sub-regions of said line;

investigating the map data of each of said sub-regions to determine whether the contour data thereof is higher than a predetermined density threshold;

generating interpolation contour information corresponding to said line for those of said sub-regions for which the contour information is not higher than said predetermined threshold;

for each of said sub-regions for which the contour information is not higher than said predetermined density threshold, determining a corresponding part of a second one of said different topographic map data;

generating contour information corresponding to said line by analysis of contour information of each of said sub-regions for which the contour information satisfies said predetermined threshold and contour information of said parts of said second one of said different topographic map data; and

displaying said contour information.

15. A method of topographic processing, comprising:

storing at least one map of map data, said map data including contour data;

defining a line on said at least one map for contour information display;

defining a plurality of sub-regions of said line;

investigating the map data of each of said sub-regions to determine whether the contour data is higher than a predetermined threshold;

for each sub-region for which the contour data does not satisfy said predetermined threshold, generating interpolation contour data;

generating contour information corresponding to said line by analysis based on said interpolation contour data and contour data from each of said sub-regions of said line; and

displaying said contour information.