Questions tagged [tesselation]
A tessellation of a two-dimensional area into plane figures that fill the area with no overlaps or gaps. In three-dimensions, we can similarly tesselate into polyhedral blocks.
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Buffer without overlaps in Python
I have a set of points with respective lat/long coordinates and each point has a given value associated with it (basically a field measurement). I would like to draw buffers of a given radius around ...
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SF Tessellation not working [closed]
I am fairly new to using sf and R in general and I keep running into a frustrating problem. I'm using the method outlined in this tutorial and I am getting the following messages:
Warning messages:
1: ...
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PostGIS tesselation invalidating polyhedralsurfaces
We are trying to visualise prefabricated concrete elements.
These elements are exported in an ifc format. https://technical.buildingsmart.org/standards/ifc/ifc-formats/
We have already been able to ...
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ST_Tesselate on PolyhedralSurface is invalid : Polygon 0 is invalid: points don't lie in the same plane (and Is_Planar() only applies to polygons)
Using PostgreSQL 15/PostGIS 3.4.0, I am having troubles when tessellating some polyhedral surfaces. Indeed, I have a table where 99% of the surfaces are giving correct tessellation results, but few of ...
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Tessellation on huge dataset
I have a set of CSV files with lat/long for points spaced every 500 meters apart. There are several files that collectively span a huge area across the Nevada/Utah border.
I need to create a ...
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Speeding up a TIN to MultiPolygonZ conversion in PostGIS
I have a TIN record in a PostGIS database. It contains between 50'000 and 100'000 triangles:
Based on this answer: https://gis.stackexchange.com/a/209845/65370 I'm trying for the moment to dump the ...
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PostGIS SFCGAL ERROR: PolyhedralSurface is invalid : inconsistent orientation of PolyhedralSurface detected at edge 0 (0-1) of polygon 3
I am trying to tesselate (yes, in the following case the tessellation is perfectly useless, but it's for the purpose of the example), with the help of ST_Tesselate() from SFCGAL, a polyhedral surface ...
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Tessellation will not display quadrat totals when plotted (spatstat, R)
I have tessellated an image, and am trying to plot the number of quadrats that appear in each tessellated region.
I have two problems here:
My tessellated image will not plot with my gw_ppp points, ...
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Generating tessellation in ArcGIS Desktop versions before 10.3
I'm using ArcGIS Desktop 10.2.2 and want to generate a tesselation grid but this tool is available in 10.3 or versions of ArcGIS.
Is there any way I can generate a hexagon grid for my study area using ...
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Making polygons created by Concave Hull algorithm contiguous
I have a set of points grouped and enclosed by a Concave Hull polygon as in this question. Within an outer boundary that encloses all the polygons I would like to make these polygons contiguous, that ...
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Using Calculate Value to get extent of feature to input into Generate Tessellation tool
Here is what my model looks like:
Takes Excel with lat/long and plots points
Splits by name field
Iterate
And buffer into separate .gdb
Calculate value then pulls from the buffer.gdb
This is where I ...
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Generating hexagon (tessellation) fishnet inside hexagon (tesellation) fishnet using ArcGIS Pro
I'd like to create a fishnet or hexagons inside a subset area of hexagons? Basically I want a large cell size for my rural area and a small cell size for the urban area. This is the tool I've used to ...
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Tessellate polygon geometry in a Python script
Is there a way to tessellate a polygon geometry object, by using an existing method/function? A function call similar to feature.geometry().tessellate(). I know that there's an existing script in the ...
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Generate Tessellations looping through all shapefiles from folder in ArcGIS Pro ModelBuilder?
I am trying to create Hexagonal grids for each shapefile in a folder. I opted for ArcGIS Pro ModelBuilder tool and was successful in creating a loop that reads and loads shapefile in the memory. But ...
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Optimal tiling of polygon using ArcGIS Desktop?
I am trying to tile a polygon with a minimal number of fixed sized squares.
Currently I am creating a fishnet over my polygon then spatially joining the squares that intersect the polygon. This is ...
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Apollonius Graphs (Delaunay Graphs of Disks) in sfcgal or PostGIS?
I was wondering if there is support for Delaunay Graphs of Disks (a.k.a. Apollonius Graphs) in PostGIS/sfcgal?
A CGAL function seems to exist for this. But I can't seem to find it in the PostGIS ...
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Generate a grid through an extensive area without killing my machine
I need to generate a grid of 10x10m on a certain extent so I can extract only the squares that have some area inside of a certain shape.
My problem is that the shape I need to extract those squares ...
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Merging tesselating regions depending on size?
I have the following regions marked up over map
Each region has assicated statistical data.
The problem is that sizes of these regions are very different. Some regions are very big and another ones ...
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Generate Tessellation & Centroids using ArcGIS Pro?
I first generated a square tessellation (using Generate Tesselation) using the following:
arcpy.GenerateTessellation_management(Output_Feature_Class="/File Location Removed", Extent="371935.1483 ...
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Converting TIN to Multipolygon in PostGIS?
ST_Tesselate returns TIN geometry. But then I need to use other software to process geometry data and it only accept (multi-)linestrings and (multi-)polygons.
Is there way to convert TIN triangles ...
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Make a shapefile with geopandas from polygons
I am new in dealing with shapefiles. I have a dataset with points that represent centroids of polygons. I want to do a Voronoi tessellation and create a new shapefile with the obtained polygons ...
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Create history map with inkscape with each country as a distinct object
I want to create history maps (maps showing historical borders) with inkscape and to have an object for each country.
I want to draw borders between countries only once and have this part of a path ...
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Cutting out the world into polygons of equal population size
I would like to cut out the world into polygons of equal population size, say 100 million persons (starting for example with raster data of population density as provided by the NASA). I know that ...
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Is there Open Source equivalent to ArcGIS Integrate (for topology correction)?
I need to transform a set of polygons so that it forms an exact spatial partition/tesselation (no gap - no overlap). What are the existing open-source solutions (software or library) to perform this ...
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