The process of converting the geographic features on an analog map into digital format using a digitizing tablet, or digitizer, which is connected to a computer.

learn more… | top users | synonyms (1)

4
votes
4answers
2k views

How to Digitize Free Satellite Imagery in QGIS - Alignment issues with Openlayers Plugin

I am trying to digitize OpenLayers data (such as Google satellite imagery) with no success. Whenever I try to move or zoom the canvas the vector layer I digitized loses the position relative to the ...
1
vote
1answer
544 views

How to go with…somewhat complex geological maps in QGIS?

Just a follow-up to this question QGIS: Line to polygon conversion. Not sure do i have to continue there itself... We are currently digitizing a geological map...which has 36 features in total. Some ...
10
votes
3answers
5k views

How to create polygons with straight lines and right angles in QGIS?

I am running QGIS 1.7.0 on Mac OS X 10.6.8. When creating a polygon, how do I do it so that the lines are straight (90, 0 degrees, etc.) and when I create corners they can be right angles? For ...
9
votes
3answers
1k views

How can I digitize features on an Y,Z plane in ArcGIS?

How can I geo-reference and digitize features on a Y,Z plane of a vertical cross-section in ArcGIS? The surface coordinate system is NAD 83 UTM 15. This is a simplified version of the question found ...
6
votes
3answers
3k views

How to digitize a raster automatically

I have a raster (.sid extension) file. I want to digitize roads automatically in ArcMap, QGIS..etc. Digitizing by hand would be too time consuming. How can i do this ? Thanks
5
votes
2answers
6k views

snapping polygons and lines

I recently downloaded QGIS on a Mac OSX 10.7.4 (lion) and purchased a master map shape file, of a particular area. I am trying to divide it into polygons following features on the master map vector ...
4
votes
0answers
736 views

Does QGIS have these CAD editing functions? [closed]

I tried QGIS for the fist time today and it seems quite capable for the task that I have in mind. However, I really miss some basic editing functionality from another GIS software that I have to use ...
7
votes
1answer
1k views

Is there a way to automatically snap loose points of lines to close by vertices with Quantum GIS?

I have a vector layer of lines that were drawn with the snapping option off. I need to have them snapped but, there are hundreds of lines. Is there any solution to do this automatically or ...
3
votes
2answers
147 views

I am unable to draw a shape layer

When I add a new shape layer or want to edit an existing one, nothing is happening. I even don't see the dots where I'm clicking. Maybe the problem is I deleted some layers (by opening the .qgs as a ...
3
votes
0answers
101 views

How to digitize 90 degree angles? [duplicate]

Possible Duplicate: How to create polygons with straight lines and right angles in QGIS? In QGIS 1.8 is there a way to digitize buildings etc. with perfect 90-degree angles, Or, edit a ...
2
votes
1answer
164 views

How to find the projection of an image?

Instead of georeferencing the image and deforming it, I'm trying to find the projection used by the author of the image. I've got tens of these distribution maps to digitize. The idea is to avoid ...
2
votes
2answers
112 views

Digitized Shapefile manually using wrong projection: how to fix it?

I have a raster in correct projection. I used shapefiles, and marked objects (manually), but I found out that my vector layers have different projection, so they have different size and position. Is ...
1
vote
1answer
437 views

How to indicate flow of a watershed feature?

While tracing and digitizing rivers, streams, rivulets, etc., is it possible to indicate the direction/flow in the shapefile on QGIS? I'd like to avoid using map labels. Ideally, when done tracing, I ...
1
vote
1answer
299 views

Can I resume (continue) digitizing a polygon feature from any vertex?

When I digitize in ArcMap with a Wacom tablet and a pen I often accidentally double click and finish my sketch. More often then not the accidentally finished sketch crosses itself. I would like to ...
1
vote
1answer
120 views

QGIS: Line to polygon conversion

Currently we are working in a geological project..in which all the Contacts, Linear & some other geological features have to be captured. The thing is most of the features have to be Captured as ...