I have a kml file I want to display using polymaps. The data is from NREL Solar Resource Map.
As a kmz file it shows up quite nicely in google maps and earth respectively, however I am having trouble loading it into my polymaps/d3 environment. Does anyone know how exactly to go about this?
I can post more details if necessary
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We are using d3.js to create the maps in our application via reading .csv file that has latitude and longitude to plot the location but sue to huge data (~200k latitudes and longitudes in the .csv file) the maps creation is taking around 1 minute.
To avoid this much of delay we are exporting the maps into an image using SaveSvgAsPng.js library and once the image is created we are displaying the image on the app instead of creating the map every time the user logs into to the application (below is the code snippet from saveSvgAspng.js library)
Now with this approach we are seeing each time the image is exporting differently and there is drop in the image quality of the map (attached the image)
Raising this here to get some help in fixing this issue or if someone has faced this before as this is being the show stopper for our application. Happy to add more details if these are not sufficient.
I have 1500 pictures that need the address where they were taken to be shown in the corner of the picture. I have the pictures geo-tagged.
I need help extracting the GPS data and converting that to an address.
Then getting that address and saving it into the picture in the bottom right corner. Can anyone help or point me in the right direction please?
You're going to need two things. First you need an application that will extract the EXIF data that you are interested in. You should be able to write this yourself as it is fairly simple to do. You will need the JPEG standard and just need enough of it to identify the markers; specifically the APPn markers. You are also going to need the EXIF and (possibly the) TIFF standards to figure out how to extract the data you need form the EXIF APPn marker.
Writing the information to the corner of the image is the tough part. There are probably command line applications that will allow you to do that already. If worst comes to worst, there are various language API's that will allow you to read a JPEG stream into a buffer; draw text to the buffer; then write the buffer back to a JPEG stream.
You will most likely need to use a programming language for this; I think Python would be suitable as it's easy to get started and has libraries needed for your task.
For example, in order to extract the location (coordinates) from the JPEG files you can use pyexiv2.
To transform those coordinates to addresses you need to use a geocoding service such as Google's Geocoding API - you can use their Python library directly or code your own using something like requests.
Now that you have the address data you can overlay that data onto images using Python's pillow library.
If you're looking for some code to get started let me shamelessly plug my own project called photomap; you can find code to read GPS information from images here: https://github.com/iticus/photomap/blob/master/handlers.py#L170
I have a contour map that is provided to me by a private company. it comes in the form of a .dwg that works for autocad. In the past i have gotten contour data from usgs but the data provided to me is much more accurate. I want these contours in the .dwg to get loaded into arcmap so I can use them to delineate watersheds as per usual procedure.
Try to open .dwg file from ArcMap's add data option, locate the .dwg file, double click on it and it will show you it's sub-files, open Polyline file or any other file from it as u desire.
Then you can create its boundary and DEM to carry out your tasks.
I'm sorry this is probably a very basic issue, but I just can't seem to figure it out.
I wanted to map some data using D3.js and the map shape I wanted to use is provided by the UK's Office for National Statistics. I managed to get their geojson data to display, but as soon as I try to do anything with scaling, transforms, topojson, I've been a complete failure.
I've been through many, many, different approaches and I think it's something about the map data that is causing the issue. If I open the shape files in Mapshaper it looks perfect. If I export as geo or topojson and re-import, it looks perfect. If I try to run geo2svg on the geojson export it produces a lot of data, but nothing visible. If I try to import the original shape file into mapstarter.com it produces a flat line. And if I put the topojson into the D3 v4 bounding example I end up with a load of random triangles.
So, can someone show me how do you get ONS mapping data such as http://geoportal.statistics.gov.uk/datasets/1bc1e6a77cdd4b3a9a0458b64af1ade4_3 to display in a d3 example such as https://bl.ocks.org/iamkevinv/0a24e9126cd2fa6b283c6f2d774b69a2?
Thanks
The data that you have linked to is projected. Mapshaper supports projected data, but using d3.geoProjection with projected data will result in no data being displayed in most situations. You need to ensure your data is in lat long pairs for proper display with a d3.geoProjection.
Luckily, in Mapshaper you can reproject your data. Copy all the files of the shapefile into mapshaper, and in the console change the projection to wgs84 (unprojecting your data):
proj wgs84
This data is now easily displayed and manipulated using a d3.geoProjection. Here is an example using the data that you referenced. Also a screenshot:
Lastly: It is possible to display projected data as well, but this is much less common.
I have (or, rather, will soon have) a number of maps created in ArcGIS 10.0 and exported as PDF documents. The maps all show contiguous areas, being rather like the pages in a map book. There will also be a smaller-scale map depicting the entire area (let's call it the "study area"), but with less detail, rather like that page of a map atlas that shows what page depicts what area.
I wonder if there is any way to create thumbnails of the larger-scale maps and mosaic them such as to create an index map of the study area. A user would then be able to see, for a particular point on the smaller-scale map, which of the larger-scale maps depicts that part of the study area. (And perhaps see that map by clicking on the larger map?) Does anyone have any ideas I can implement this? I would prefer exporting the maps in PDF format, but, if I can't do all of the above with PDF, then any other format to which a map can be exported from ArcGIS, such as JPG or TIF, will work.
You should be able to create a PDF which does this.
What you need to do is render each page to a small image.
Then collect each of these images and add them as a mosaic to an index page.
Then put links from each small image back to the original PDF page.
If the hierarchy was more than one level deep you could repeat the process.
You need a PDF component to do this. What you want in terms of features is something which does decent PDF rendering. It's an easy thing to do badly and a difficult thing to do well.
ABCpdf .NET does good quality rendering so it's what I would suggest, but then I would because I work on it. :-)