I am working on some maps and animations using the html5 canvas element (example visible here.) I would like to be able to efficiently generate pixel-valued linestrings (x1, y1, x2, y2), ideally from PostGIS, based on the geometry of the canvas. That is, in pseudo-geojson: "Coordinates":"[[-122.0, 35.0], [-121.0, 36.0]]" might outpu...
Hello guys! Good day! I'm trying to display on the web (read as create a GIS Web app) topo data layers stored in a POSTGIS/POSTGRES spatial database using mapserver. My problem is, although i happened to come across different framework that 'I' could use, my lack of experience on using mapserver in the first place makes me indecisive of...
For my company in house use i want to develop a gis project with simple goals. To display all places with name wherever my company presents,over the normal country map. Connect main office with branch offices graphically ( by line ). By clicking a place user will be directed to a new page containing information about the place. add new...
A local real estate agent is wanting to add Google maps to his web site that display his listings. However, rather than just showing map markers to all his properties, he wants the web site visitor to be able to draw an arbitrary polygon on the map, click a button, and then display all his houses within those bounds. My understanding i...
The gnomonic projection maps spherical triangles to straight-edged plane triangles. But I've heard that the Chamberlin trimetric projection has less distortion, so I'd like to use that instead. Alas, when I use my (extremely rough and probably buggy) implementation of Chamberlin trimetric projection to map the spherical triangle formed ...
I have a problem that involves a UAV flying with a camera mounted below it. Following information is provided: GPS Location of the UAV in Lat/Long GPS Height of the UAV in meters Attitude of the UAV i.e. roll, pitch, and yaw in degrees Field of View (FOV) of the camera in degrees Elevation of the camera w.r.t UAV in degrees Azimuth of ...
Hi , I am not clearly understanding the extent parameter in GIS applications. for ex, In mapserver map file we are using NAME "CGI-CONTEXT-DEMO" STATUS ON SIZE 400 300 **EXTENT -2200000 -712631 3072800 3840000** UNITS METERS IMAGECOLOR 255 255 255 IMAGETYPE png here extent means lower left x,y and upper right x,y. but long,lat values ...
Is it possible to connect Oracle with ArcGIS for doing spatial query? ...
hello, my question is: As introduces a variable [i] into a string in python. For example look at the following script, I just want to be able to give a name to the image, for example geo [0]. Tiff ... to geo [i]. tiff, or if you use an accountant as I can replace a portion of the value chain to generate a counter. data = self.cm...
I got the impression from other programmers that GEO (wgs84) coordinates are not efficient for calculating distance at meters resulotion. My Goal is to calculate accuratly (meters) distance between 2 points (at the same country) by using global coordinates (UTM Or Geodetic(wgs84)) ,in which set of global coordinates you recomand to use ?...
Does anyone know where I could find a library of code for converting Lat/Lon position to Military Grid Reference System (MGRS)? I'm looking for a C# implementation if possible. ...
I am creating a mapping application that uses a WSGI service and needs a different config file for each map. Currently, I launch the service with: import os, sys tilecachepath = '/usr/local/lib/python2.6/dist-packages/TileCache-2.10-py2.6.egg/TileCache' sys.path.append(tilecachepath) from TileCache.Service import Service, wsgiHandler f...
How I can convert a shape file (GIS) to text? or, How I can extract the information in a shape file? ...
Does anyone have a recommendation for a work flow for georeferencing high resolution aerial photography using open source tools? I have GPS coordinates for control points and would need to associate them with the imagery (I do not know the pixel x,y values). Also, any open source options that can perform more sophisticated correction l...
I have a typical database with millions of polygons as land parcels and i want to split these polygons onto lines and then remove the lines that overlap eachother. These lines will be used purely for rendering in mapnik/and or geoserver as at the moment every parcel boundary gets rendered twice. i propose to split the parcel polygons i...
Hey folks: Thanks for the assist on my previous question.... I was able to complete my project This time I have a CAD file created with Autodesk that I need to convert to a shape file. Couple of questons: An open source application (can't afford ESRI) that can convert the CAD file to a shape file? Is that a better file format I can u...
Can anyone see anything wrong with the following set of commands? Every time I run these image.png is a image of the UK and not the JOSM map I exported. I'm guessing there's something awry with the db import however the output mentions that it's processing my coords and data. Steps: 1 - Exported a .osm file from JOSM or Merkaator. 2 -...
Given a set of floorplans (in Autocad, svg, or whatever format need be...), I would like to programatically generate directions from point A to point B. Basically I would like to say: "How do I get from room 101 to room 143?" (or for triple bonus points, from room 101 to room 323). Anyone have any ideas how to go about this? I am pre...
I have a three lat-lon coordinates that make up two line segment A to B to C. I also found a function that can return north-bearing of a line segment A-B or B-C in -180 to 180 manner. However, I'm having trouble to determine when a car reaches from A to B, should it turn right or left to continue to C. ...
Does anyone have any experience of plotting DAFIF data in ESRI products? are there any DAFIF to shapefile conversion utelities or libraries out there? ...