Method for visualizing a complicated metro map in a limited displaying area

• US 8,907,954 B2
• Filed: 03/16/2012
• Issued: 12/09/2014
• Est. Priority Date: 12/16/2011
• Status: Expired due to Fees

• Current Assignee: National Chiao Tung University (Government of The Republic of China)
• Original Assignee: National Chiao Tung University (Government of The Republic of China)
• Inventors: Wang, Yu-Shuen, Chi, Ming-Te
• Primary Examiner(s): Perromat, Carlos
• Assistant Examiner(s): Flora, Nurun N
• Application Number:
  US13/422,108
• Publication Number:
  US 20130155115A1
• Time in Patent Office: 998 Days
• US Class Current: 345/440
• CPC Class Codes: G06T 3/04 Context-preserving transformations, e.g. by using an importance map panospheric to cylindrical image transformations G06T3/12

Abstract

The prevented invention provides a method to visualize complicated metro maps in a limited displaying area, in which the route to the passenger'"'"'s destination is highlighted. In order to achieve high readability, it sets 1) the distance between neighboring stations to be equal, 2) the transportation lines to lie in octilinear directions, 3) the angles of incident edges at each station to be maximized, and 4) the station positions to be inside the displaying area. It also labels the names of stations that passenger will pass by to make the route navigation easy and intuitive.

Claims

1. A method for visualizing a metro map in a limited displaying area, wherein said metro map contains a plurality of routes, each said route has a plurality of station nodes, each pair of adjacent station nodes are connected by an edge, and said method comprises the steps:

a. download a geographic metro map covering a focal route and neighboring transportation networks, the focal route being defined by a start station node and a destination station node that are given by a user, the focal route having a set of focal station nodes including said start station node, said destination station node, and focal edges connecting the focal station nodes, the neighboring transportation networks including contextual routes having contextual station nodes and contextual edges connecting the contextual station nodes;

b. selectively magnify focal station nodes and said connecting focal edges, said focal edges within said focal route being magnified to have a predetermined length greater than a length of the contextual edges outside of said focal route, and deform said focal and contextual routes to generate a smooth metro map;

c. rotate said focal and contextual routes to lie in octilinear directions; and

d. selectively label only station nodes of said focal route with identifying names.

2. The method for visualizing a metro map in a limited displaying area according to claim 1, wherein said edges which are adjacent are encouraged to have identical directions.

3. The method for visualizing a metro map in a limited displaying area according to claim 1, wherein said station node that is connected with a plurality of said edges is enforced to have identical included angles.

4. The method for visualizing a metro map in a limited displaying area according to claim 3, wherein said station node that has only two connected edges is constrained to be collinear with adjacent station nodes respectively connected via said two connected edges thereto.

5. The method for visualizing a metro map in a limited displaying area according to claim 1, wherein each station node is within the space boundaries, and said edges that have no sharing station nodes do not intersect.

6. The method for visualizing a metro map in a limited displaying area according to claim 1, wherein said edges are rotated to be vertical, horizontal 45-degree, or 135-degree diagonal to obtain a schematic layout.

7. The method for visualizing a metro map in a limited displaying area according to claim 1, wherein a Gaussian Newton method is used to solve non-linear optimization, and said stations'"'"' positions and said edge orientations are iteratively updated to deform said metro map.

8. The method for visualizing a metro map in a limited displaying area according to claim 1, wherein said station nodes and said focal edges that the user will pass by are highlighted via magnification and said contextual edges are demagnified.

9. The method for visualizing a metro map in a limited displaying area according to claim 1, wherein an optimal orientation of each station label is computed by minimizing penalties that are measured from preference, consciousness and occlusion of said station nodes.

10. The method for visualizing a metro map in a limited displaying area according to claim 9, wherein a quadrangle is computed based on said label, and said quadrangle is used to check whether or not said label intersects other labels.

11. The method for visualizing a metro map in a limited displaying area according to claim 10, wherein a quadrangle having double length extending in one of its directions relative to another direction is used to check whether or not said label overlaps said station nodes or said connecting edges.

12. The method for visualizing a metro map in a limited displaying area according to claim 1, wherein neighboring labels of said station nodes have an identical orientation.

13. The method for visualizing a metro map in a limited displaying area according to claim 1, wherein said geographic metro map is downloaded from a database or network.