An increasing number of people usually need to work or take a holiday with their families in another city. Therefore

having an accurate map is necessary when they arrive in an unfamiliar city. Some online maps

such as Baidu or Google

can provide sufficient but redundant information. Users only need some information about their destinations

but excessive details on other places give rise to difficulty in reading maps. Meanwhile

users often need to perform many tedious operations

such as zoom in and zoom out

to obtain useful information. Therefore

we present a factor graph-based method to generate multiple destinations maps. This method can provide users with only useful information so that they can obtain help easily. Our method consists of three steps. First

users select multiple destinations of interest. The detail of some areas that are far from the user destinations is unnecessary. Second

the proposed system automatically selects the most relevant subset of roads that are related to the destinations according to certain predefined guidelines. These guidelines ensure that the selected road network maintains conciseness and connectivity so that users can arrive at any destination. Finally

the layout is adjusted to present an accurate map. The map should ensure that the details of the information on the destinations are clear while maintaining the original topology of the map. Moreover

we should maximize screen usage to display more information. Thus

we identify a set of design rules to constrain the map layout. We conduct some preprocessing of the road network to implement layout optimization. We segment the road network into several rectangular areas according to the user destinations. Every rectangle contains only one destination. During optimization

we can choose a rectangular area-based perturbation or point-based perturbation. Furthermore

we use factor graph

a type of graphical model

to improve algorithm efficiency by encoding constraints as factors. We obtain the desired map layout with the Metropolis-Hastings algorithm by sampling from the target distribution constructed by the factor graph. Online maps fail to provide selective information

whereas other maps

such as hand-drawn maps

often produce map deformation that affects map reading. The multi-destination maps generated by the proposed method not only provide users with detailed road information of multiple destinations in the same view while maintaining the topology among destinations. Moreover

unnecessary information is automatically omitted. In this study

we present a new method to generate maps with a factor graph. The factor graph can clearly describe the relationships of objects. Experiment results indicate that the proposed approach can efficiently solve the problem confronting online maps

which fail to provide users with sufficient and detailed information on multi-destinations in the same view.