Questions tagged [digitizing]
The process of converting features on a map or image (either hardcopy or digital) to vector-based data in digital format.
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Create identical polygon adjacent to existing
I am currently trying to digitize FEMA flood panels and I was wondering if anyone knows how to duplicate existing polygons within QGIS. Specifically I am trying to have identical rectangular polygons ...
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Shifting point where two lines meet in QGIS 3
I am trying to digitize a road network in QGIS 3.10.12. After tracing two lines, I want to shift the point where both lines meet a bit sideways with the node tool. However, only one point from one of ...
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How to efficiently digitize objects in a PostGIS table with more than one geometry column in QGIS?
I have a PostGIS table with more than one geometry column (here: 2), like
One geometry is allways set, the other(s) may or may not be set:
In QGIS these come as two distinct layers, in my case one ...
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What is the difference for a shapefile line feature length between "Cartesian" and "ellipsoid"
I use QGIS for a hobby project on American historical railroads. When digitizing a quite short section of railroad line, giving a polyline feature in a shapefile, QGIS gives two values for the line ...
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Crop map by color
I digitized a map using QGIS. What I have right now is simply the geolocated version of the picture below (including labels, streets, lakes etc.), i.e. the file does not have any layers or attributes.
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Adding multiple features at once using QGIS
In QGIS, I can add a new line by using the Add line Feature tool. I can also use the Advanced Digiting tool which is helpful.
I want to add two line and a point in the middle of the two lines like the ...
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69
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Add Polygon Feature in QGIS: polygon lines follow cursor when digitizing
I am drawing polygons in QGIS by moving the cursor and clicking to add polygon corners. So, four clicks, four corners to a polygon. All of a sudden, the polygon lines get drawn as I move the cursor, ...
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Digitizing topographic contours to produce DEM from it using ArcMap
I have four topographic maps spanning 60 years all of which have the same scale (1:62,500). I have digitized contours (5 feet interval, 4 contours 285, 290, 295 and 300 feet) of the same section in ...
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Automatic Tracing (not tracking) of polygons in QField
Does QField support the Auto-Tracing Tool like QGIS does? Like shown in the picture above.
I tried to export my QGIS projects with the activated Auto-Tracing tool, but in QField the tool doesn't seem ...
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Align polygon borders by underlying raster values
I have an interesting problem: I have polygon borders that correspond roughly to "value-boundaries" in a raster (areas where the raster values are clearly distinguishable between two areas).
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Multi- to single-part on a subset of features
I have a question about the multi-to single-part function.
How can I apply this process to a specific multipart?
I have several multiparts, but only want to resolve one of them into its objects. ...
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Digitizing photographs of a map
Is it possible to digitize the photographs of very old maps, having no co-ordinates. The photographs are exactly like this. If possible, could somebody tell me how to proceed? I have access to ArcGIS ...
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Allow overlapping polygons in QGIS [closed]
When I draw a polygon in QGIS that overlaps an existing polygon from the same layer, QGIS automatically clips the overlapping area from the new polygon.
Is there a setting to preserve the shape that I ...
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Digitizing toolbar is gone in QGIS
For some reason the digitizing toolbar is gone in QGIS even though I checked the box:
Do you have experience with this and know how to get the toolbar back?
EDIT:
When making it as small as possible ...
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Index issue with digitising OS MasterMapdata from OS Data Hub in QGIS
Using QGIS 3.18.3 (Zurich). From the OS Data Hub (https://osdatahub.os.uk/) I've brought in the OS MasterMap "Topographic Line" data, via WFS/OGC API - Features option, and this has loaded ...
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What is the correct geometric predicate in filter for aggregate function?
I have a layer with parcels ('flurstuecke') and a layer with subdivisions ('flure'). I want to digitize parcels and autogenerate the correct number of the subdivision with an attribute formular.
It ...
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QField Freehand Digitizing, Smarthphone
I would like to use the freehand digitization tool for QField, but this does not work. I want to use it on a Huawei Y6 with an electric stylus pen. The edit mode is activated, a polygon layer is ...
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Digitizing in ArcGIS Pro
I am digitizing in ArcGIS Pro and suddenly the 'create structure and difference polygon' I had used earlier are grayed out and I can't access them again.
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QField Freehand Digitizing Tool
I saw the latest update of QField 1.8 wherein users are allowed to draw/digitize in freehand lines/polygons geometries.
I was wondering how can it be enabled in QField?
We badly need it in our ...
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Digitizing polygons against georeferenced map using ArcMap
I am drawing polygons of counties over a 17th Century map that I have georeferenced. I have an issue with this version of ArcMap which I haven't experienced with past versions.
The shape keeps closing ...
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Entering UTM coordinates with decimals using ArcGIS Pro
I have UTM coordinates containing decimals (e.g. 884305.145mN). I need to create a polygon using the Absolute X,Y,Z feature in ArcGIS Pro.
But ArcGIS Pro doesn't seem to allow decimals in UTM degrees.
...
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107
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Cannot draw straight line polygon in QGIS 3.16
I tried to draw polygon by using add polygon. It should be a straight polyline and then become a polygon but it turns to a curve line like arc (circular line) so that I couldn't draw a polygon. It's ...
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Bearing convergence in digitizing property surveys
I'm digitizing and stitching together a number of adjacent/overlapping property surveys.
The most recent ones provide clear UTM/MTM grid bearings and distances, and in some cases coordinates of ORPs, ...
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Digitizing boundaries for the educational office according to its affiliated schools
I have a layer of administrative boundaries, and within these borders, there are a group of separate schools for boys and girls, and these schools are under the supervision of several educational ...
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58
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Adding point features by machine learning in QGIS 3.16
I've got several georeferenced traditional maps and there are circles on it. (these are the studied points) So I want to add point features to the middle of the circles. I could do it manually, but I ...
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Construction mode multiple points
Is there a way to define multiple points to snap in the construction mode in advanced digitizing?
Let's suppose I want the value -26- from point 3 to 4 but also want a value -31- from point 1 to 4. ...
- 1,054
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64
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QField: Add and fill ring tool
When editing a polygon in QField, the polygon is highlighted in red. This makes it almost opaque and difficult to use the fill ring tool if digitising over a feature shown on the base map below. Is ...
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170
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QGIS Advanced Digitizing on drawing new feature with 60 degree angle
I am trying to draw a 60 degree line from the long line whenever I draw a long line regardless the angle of the long line.
But right now when I am using advanced digitizing tools and 90 degree means ...
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378
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Digitizing and adding attribute values to the points in QGIS
I want to build a digital terrain model from nautical charts. I need to capture the points where depth is indicated in the chart, and for each point, I must attribute the depth value. One by one, to ...
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73
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Adding nodes automatically without clicking the mouse
Is there a way in QGIS (or maybe in another GIS (ArcMap, for example))) to automatically create nodes at a given interval when digitizing a raster?
For example, I decided to create a Polyline object. ...
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93
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Advanced digitizing and measurement tool
I want to draw a polygon with 18m x 2m using the advanced digitizing tool. When I measure the size after creating with the measurement tool, the lengths of the sides do not match up (drawn sides vs ...
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Offsetting Advanced Digitizing lines from north in QGIS
In QGIS, I'm trying to draw some polygons (mostly rectangles) on a grid, with neat 90-degree right angles and such. All the polygons should be parallel or perpendicular to each other.
The problem is ...
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Digitising animal positions in aerial photos
Digitizing objects from orthophotos can be done using QGIS. It is just a matter of establishing a points vector layer with the right attributes and working through the QGIS user interface.
Counting ...
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Connecting end points of a line in QGIS
I have this line. You can't see the rest of the line in the picture but It's only one line and I want to connect the two ends to close it and convert it into a polygon. I don't know how to connect it. ...
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Rotating a selection of features around their individual centroid rather than the combined centroid
The rotate feature in QGIS 3 allows you to select multiple features at once and rotate them around the centroid of their combined geometries, as found in the documentation.
You can also use an anchor ...
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QAD Plugin QGIS
Is QAD compatible with QGIS 3.14 "Pi"?
I've several issues with it.
Only with the points, the rotation and simetry does not work. Polygons and lines work perfectly.
Rotate, simetry, etc, ...
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QGIS - using fill ring and snapping to segments not working
When using the fill ring tool and having to run along the edge of the polygon the fill ring tool works perfectly when snapping to a vertex, but when I try and snap to a segment, which appears to work ...
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QGIS 3x - categorized style customization function for more than 1 cryteria
I want to write down the function for my polygons in QGIS, which will customize more than 1 criteria.
I am based on my previous situation, which has been solved here:
QGIS 3x - categorized style ...
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QGIS 3x - categorized style customization based on a part of the string
I have a problem.
I am digitizing the map and I want to distinguish one group of polygons from the other group.
The basic difference between them lies in their ID (string). One of them has the ID ...
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Quickly digitising several polygons based on classified raster output using ArcGIS Spatial Analyst
I have a raster DTM of a river which I would like to split into 90 sections, each measuring 125m. I have used Euclidean Distance to outline each section by reclassifying the symbology to change colour ...
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How to set my own QDialog Form instead QGIS QgsAttributeForm
I'm working in a QGIS plugin which its functionality is to facilitate the creation of custom attribute forms with complex logic to QGIS users without python knowledge. In order to do this, the user ...
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Using Raster Tracer in QGIS v3.6.1 and it's not working
I've been trying to use raster tracer to trace some lines on simple rasters in QGIS v3.6.1, but when I use the plugin it returns the following error:
2020-06-22T11:48:25 WARNING Traceback (most ...
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Automatically fix overlaps by weight/occurrence
I'm working on a project where I have asked a number of individuals to digitize the same features on the same satellite image. For example, an image of a coast where a group of individuals each draw ...
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Adding new nodes or moving segments with Vertex Tool in QGIS 3.10
I'm used to work with simple polygons and the vertex tool. But now the Vertex Tool doesn't show me the capability of adding new nodes in centerline neither move polygon's segments. The function just ...
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3
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Transferring Z attributes to polygon layer in QGIS 3.10
I have a point layer with the z attribute (and there is a field with the same z value). I have digitised a polygon, snapping to the point layer. How can I transfer the z value from the point layer to ...
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Using QGIS to convert collection of map rasters in various projections to simple latlong
I am currently building a global database of sutures, major faults and thrusts, orogenic events, magmatic episodes and plate boundaries with the goal of building a framework of Earth's tectonic ...
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Digitized polygon not lining up with others of same coordinate system
To start: I created a new polygon shapefile to represent an old site boundary. I set the spatial reference at the time the shapefile was created. I then started an editing session and digitized a ...
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Automatically filling area surrounded by other polygons?
I want to fill the gap with a polygon automatically. It is surrounded by other polygons but the part inside the yellow circle is another shapefile. The gap is not made by adding a ring.
Or is my only ...
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Did Digitizing tools last update remove polygon cutting?
In a previous project i used the Digitizing Tools plugin to cut polygons from other polygons.
But it seems that with a new update that feature is removed? I can't seem to use the most of the buttons.
...
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Digitizing historical Brazilian map in QGIS3.4
I am trying to overlay a map of a historical boundary (in .tif format) onto a Brazilian shapefile with subnational administrative boundaries. My general question is: what is the most direct (and ...
