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8

There is no need to manually digitize all the OSM Maps. According to the OSM website OpenStreetMap is a map of the world, created by people like you and free to use under an open license. So you are able to use the underlying data in all the maps, Simply download what you want to use, following the steps in this guide or this one.


7

I'm assuming you want to automatically populate the field with the date at which the feature was edited - apologies if this is not correct. Create the shapefile and add a field in the attribute table in which to store the date - you should be able to specify "date" as the type of input. Add the shapefile into QGIS and then open its properties. Under the ...


6

One method is to use a virtual field which would automatically number your points using the $id expression (or whatever expression you prefer): Note that you will need to save a project file for this as virtual fields are saved in the .qgs file and not in the shapefile itself (but you can re-save the shapefile as a new one using the Save As... option ...


5

Not at all. When you have some data that was digitized at 1:100,000, it excluded smaller features, which were smaller than the Minimum Mappable Area. For example, suppose you are dealing with topographic data.At 1:100,000 you would exclude large streams and trees.These features are visible at 1:24,000, and should be included in such a map. If you just ...


4

You can create a new field with the field calculator and write the current date with a simple SQL command. Open the Layer properties Enable editing open field calculator Create a new field using now from the date and time section of the functions This creates the current date on the new attribute. If you need to write the current date every time you ...


4

It looks like you solved the issue, but as I had the same issue I'd like to elaborate. My issue was with a shapefile created in Arc and edited in QGIS. All edits appeared to be taking during the edit session, but new features would disappear when saved. Any features that were modified rather than created would render correctly. The records were present in ...


4

Create nice unique id for lines Convert them to 3d using interpolate shape tool Create field fromZ in above. Use field calculator to populate it, parser Python !shape!.firstpoint.z Populate field toZ, using lastpoint.z Join 3d lines back to original, using unique id, select ones where fromZ < toZ Use flip edit TOOL to flip selected. It works for single ...


4

No. You need a Mapbox Commercial Satellite licence. https://www.mapbox.com/tos/#[YmtIyw] You may trace Mapbox-hosted imagery in order to produce derivative vector datasets for non-commercial purposes, and for OpenStreetMap. If you wish to produce derivative vector datasets from imagery for commercial purposes, you must buy a Mapbox Commercial Satellite ...


3

I think you talk about the id of shapefiles, if so you can go to layer properties (doubleclick the layer) then go to fields and set the item that is called 'Bearbeitungselement' in german to UUID-Generator (id field type must be text) as shown in the screenshot below (https://en.wikipedia.org/wiki/Universally_unique_identifier). When digitizing your ...


3

The Digitizing tool does not work correctly with on-the-fly reprojection. If you need the project CRS to be EPSG:3857, reproject the shapefiles layers using Save As ... to another filename and EPSG:3857, and remove the original layers from the project. Then you can use the digitizing tool without error messages. Once finished with digitzing, you can save ...


3

You have to georeference the raster first. Its not just about a CRS, but the extent of the raster (in CRS units) too. You make yourselve double work if you digitize data from the raster, and then try to adjust that to reference maps like bing. There are a few tools to georeference vector data, but you will not have the convenient "pick from canvas" tool.


2

Yes, you can definitely use USGS National map ortho-imagery to extract features, using heads-up digitizing methods (HUD.) The trick here is to work within a projected environment using UTM or State Plane as a coordinate system to ensure fidelity. Another consideration should be the age of the image. Ensure you are working with the most current image possible ...


2

Generally speaking, for vector geometry (e.g. roads, buildings, polygons, areas of interest) these features are created by outside contractors that specialize in geospatial data production. However, the tech companies like Google/Apple/Microsoft must also QA/QC the massive datasets for inaccuracies. A lot of this can be done programmatically by their ...


2

You can generate a 1 by 8 grid with bounds set to the bounds of you polygon. Then clip your polygon with the cells of this grid. The product would be eight equally proportioned sections of the original polygon.


2

I haven't tried it, but there is the CalcArea plugin, which apparently "calculates the area of a polygon while it's being created or edited".


2

I don't think there will be you can have non-rectangular shapes kept at a constant size, if you move one corner what decides how the others are moved to adjust the size? I would say just create one feature the right size and copy it around as required but since some will be irregular (not right angles) I suggest setting a label with the area so you can ...


2

You didn't specify it in your question but it looks like you are using QGIS. The "Split selected feature with select line from another layer" tool is from the Digitizing Tools plugin. You may need to download/install from the toolbar menu: Plugins > Manage and Install Plugins Once installed and enabled, it should show up in the toolbar. If not then right-...


2

First follow this tutorial to convert raster to vector in QGIS. http://manual.linfiniti.com/en/complete_analysis/raster_to_vector.html Next make selections on the shapefile, based on the attribute values of the countries. Finally export the selection.


2

To change the cursor on the application level type into Python console: from PyQt4.QtCore import * from PyQt4.QtGui import * # action cursor QApplication.instance().setOverrideCursor(Qt.BusyCursor) Or to set a custom bitmap as the cursor (this might be simply a yellow cross): # customized cursor QgsApplication.instance().setOverrideCursor(QCursor(...


2

There are a large number of FOSS options that would be suitable for a project like this. I am going to end up recommending that you use QGIS. I will address the question in three parts: Non-GIS options. GIS options, and why I recommend QGIS. Some pointers to QGIS tutorials. Non-GIS options Since you have come to a GIS-focused site, you are indicating ...


2

If you do choose to use a CAD, rather than GIS program for your needs, There are also open-source CAD programs like QCAD.


2

A free tool that will help you explore what you can do within GIS, is QGIS. It will most likely be a little tricky to digitize and import the information but you can start with loading a basemap (say Openstreetmap) and trace out the boundary of your property. Then, you can try to import some scans of your paper copies and geo-rectify them. This just means ...


2

In the next release (8 july 2016) this wil be fixed. Have a look at http://changelog.linfiniti.com/en/qgis/version/2.16.0/ There you can read: Feature: Extend linestring geometries with reshape tool The reshape tool now allows you to extend linestrings, by starting a reshape at either a line's start or end point. This feature was developed ...


1

You should change you project CRS to match that of the layer you are editing, and not the Layer's CRS from it's properties menu, as that is simply incorrect.


1

There is a Leaflet plugin called Leaflet Draw https://github.com/Leaflet/Leaflet.draw You would have to write some code to export the drawing to a data file, ie. GeoJSON, that the user would download...


1

The mmu is based on many things. From the picture you have there it is not possible to tell and it should be done before you digitize a map. Some hints how you can estimate the mmu: what are the requirements? the smallest objects that need to be mapped and if they are for example needed as polygon or just as point what are the technical boundaries? for ...


1

You can certainly change the size of the cross using standard properties. I don't think you can change the colour, though. Settings > Options > Digitizing > Vertex Markers and change the size value. Detlev's suggestion is great, although it does affect the whole app, not just digitizing, so be careful how you design the icon (the cursor hotspot seems to ...


1

I have downgraded my qgis to version 2.0.1, now it works. It seems to be a bug in the new version.


1

I wouldn't say it's a hopeless task. After all, these aren't random points - you know they are going to form a linear feature. I spent about 10 minutes with FME - using a dataset of a trail sorted into a random order - and think the NeighborPairFinder transformer is your friend here. It works because for each point on the trail you find the two nearest ...


1

Orthoimagery from The National Map is technically already digital data. Regardless, you may conduct manual on-screen digitizing with USGS orthoimagery as a base to trace specific entities such as houses and roads. Bear in mind the coordinate system of imagery and the feature class you are doing your tracing with to ensure they match while tracing. Also, ...



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