maps

问题 I'm creating a simple application in Java and I would like to be able to show some points and paths on a map (a road map, not a satellite one). I have been looking for some API that would let me do this, but Google Maps API isn't available for Java and can be only used for web applications, and WorldWind didn't seem to offer road maps and the size of the API was a bit bigger than I would fancy. Do you know of any API that would meet my needs? Thanks in advance. 回答1: Is it a web application?

问题 I am plotting some maps using Matlab that use mapshow to plot the country border from a shapefile. I then export them to both a PDF and EPS format using the export_fig package. This worked completely fine using Matlab 2014a, but I have just upgraded to Matlab 2014b to take advantage of something else that has improved, and now my country border is all jagged. The border only looks jagged on the saved versions of the file. If I zoom in on the figure window, the outline isn't like that. Here

问题 Does Google Maps have a tile API to receive meta information about buildings? For example: HERE Maps offers a tile API to obtain information about buildings. But data is mainly only in cities available. See: Here Map Tile API. A response from the HERE Map Tile API looks like this: { "metadata" : { "street labels":[ { "name":"Danziger Straße", "font size":"13", "vertices": [ 38.21, -18.57, 79.17, 4.82, 88.82, 10.34, 121.50, 30.46 ] } ], "labels":[{ "name": "111", "type":"TEXT", "bounding boxes

问题 I would like to draw a map of the US over an image, but then fill in the oceans. here is my starting point: library(maps) library(graphics) image(x=-90:-75, y = 25:40, z = outer(1:15, 1:15, "+"), xlab = "lon", ylab = "lat") map("state", add = TRUE) But I would like the Atlantic Ocean and Gulf of Mexico to be filled in a solid color. 回答1: Good question! How's this? library(maps) image(x=-90:-75, y = 25:40, z = outer(1:15, 1:15, "+"), xlab = "lon", ylab = "lat") map("state", add = TRUE) library

问题 Can anyone offer suggestions as to the best way to deal with transparency and alpha levels with many layers (with reference to ggplot2 )? In the sample code below, it becomes very difficult to see individual state borderlines (e.g. South Carolina, North Carolina, Virginia) -- I have tried setting alpha=0.00001 but this appears to make things worse... library(ggplot2) all_states = map_data("state") set.seed(103) df = data.frame(long=sample(-90:-70,100,T), lat=sample(30:45,100,T)) p = ggplot()

问题 Maybe due to the fact I'm relatively new to R, I have problems using the gadm-Mapfiles on http://www.gadm.org/. I try to draw a map with several countries and compare them to each other (using different colors). This is what I do library('sp') ## load(url('http://biogeo.ucdavis.edu/data/gadm2/R/ARG_adm0.RData')) # loads an Object "gadm" with shape of Argentinia arg <- gadm # is there a more convenient way to do this in one line? load(url('http://biogeo.ucdavis.edu/data/gadm2/R/CHL_adm0.RData'

问题 Maybe due to the fact I'm relatively new to R, I have problems using the gadm-Mapfiles on http://www.gadm.org/. I try to draw a map with several countries and compare them to each other (using different colors). This is what I do library('sp') ## load(url('http://biogeo.ucdavis.edu/data/gadm2/R/ARG_adm0.RData')) # loads an Object "gadm" with shape of Argentinia arg <- gadm # is there a more convenient way to do this in one line? load(url('http://biogeo.ucdavis.edu/data/gadm2/R/CHL_adm0.RData'

问题 Does anybody know any free of charge android maps library that has 3D capabilities? I know for sure that google maps doesn't support 3d when using the sdk library. The provider is not a problem. I'm not married with google maps, nor any other. The following are apps that can be used as example of what i'm trying to accomplish. Waze https://play.google.com/store/apps/details?id=com.waze Route 66 https://play.google.com/store/apps/details?id=com.route66.maps5 Example 回答1: I want to mention this

问题 Using the Google Maps API, how can I get the latitude and longitude of the corners of the map display area? That is, if my map is 300px wide and 400px tall, how can I find the lat-long of the points at (0,0) and (300,400)? 回答1: Use getBounds(). From the doc: Returns the the visible rectangular region of the map view in geographical coordinates. That function returns exactly what you want: the southwest and northeast corners of your map. The first pair of coordinates are the lower left

问题 Using the Google Maps API, how can I get the latitude and longitude of the corners of the map display area? That is, if my map is 300px wide and 400px tall, how can I find the lat-long of the points at (0,0) and (300,400)? 回答1: Use getBounds(). From the doc: Returns the the visible rectangular region of the map view in geographical coordinates. That function returns exactly what you want: the southwest and northeast corners of your map. The first pair of coordinates are the lower left