Questions tagged [computational-geometry]
study of algorithms which can be stated in terms of geometry
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Land allocation to polygons with specific areas within a boundary
We are looking for a solution to create novel land allocations of an existing area into a subset of polygons for each allocation within the existing space.
A high level overview of the requirements ...
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Can single 2D LiDAR perform multiple object tracking?
The objective is to track movement of multiple products in a conveyor belt right from the beginning to end of a conveyor belt and monitor the start and end time of the movement of a particular product ...
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Finding the closest point on a line to a given point (and their distance) efficiently
I am working on a problem that involves some geometry and spatial points. Given a query, consisting of a point p and a line L (point not necessarily on the line), then find the point q on L that is ...
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Point projection on a polygon along each axis
There is a method in this thread that allows defining a concave outline around a 2D set of points.
import alphashape
import matplotlib.pyplot as plt
from descartes import PolygonPatch
points = [(17, ...
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How to find geographic coordinates of intersection point of two lines originating from two different geographic coordinates?
I have two planes emanating from two different geographic coordinates as per wgs 84 reference ellipsoid namely (lat1, long1, alt1) and (lat2, long2, alt3) with a bearing b1 and b2 with respect to ...
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Splitting Streets to Create Polygons?
I have a need to take all the streets belonging to a certain area (in OpenStreetMap) and split each street by each other and form polygons from the segments that result from the split operation. I do ...
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Extruding mesh along parametric curve and applying earth curvature?
I'm working on a railway generation project, I must generate 3D meshes for the track (rail, ballast, ...). Track origin is defined geographically (latitude/longitude/azimuth/elevation), then the ...
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"Average" of two lines
I have a dataset of pairs of parallel linear features (railway tracks) and I need to simplify each pair into its central/median line. This could be achieved by computing a skeleton as suggested in ...
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Delaunay triangulation algorithm in shapely producing erratic result
I would like to triangulate the following polygon:
The wkt for the geometry is given as follows:
POLYGON ((3 0, 2 0, 2 0.75, 2.5 0.75, 2.5 0.6, 2.25 0.6, 2.25 0.2, 3 0.2, 3 0))
I ran this code to ...
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Points on the opposing side of a breakline
If you have a breakline or even a single line segment within a DEM, how can you tell if two points lie on the opposing side of that breakline or line segment? From a computational geometry standpoint ...
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Pattern recognition - machine recognition of plausible shape of a polygon
I have a schoolproject where the task is to locate all possible shapes (of a certain complex polygonic structure) in a layer of several heterogenous polygons.
And now the task is to find all the ...
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Closest Point Pairs to determine grid resolution
I'm reading Hengl's (2006) Finding the Right Pixel Size.
In it, among many different suggested approaches, he suggests using a grid resolution where > 95% of the closest point pairs do no fall into ...
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Is there an established method to declare "Forward" on a linear feature
Is there an accepted way to establish a Forward direction for a linear feature regardless of the ordering of the points used to store the feature?
An example would come from Roadway Design in the ...
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Is this Fastest, most Elegant and Extendable to nD implementation of AABB Intersection?
I recently did an AABB (Axes Aligned Bounding Box) Intersection implementation on 2D and 3D objects for which I came up with such a short (and very fast) solution as follows.
The demonstration below ...
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What algorithm allows me to calculate the set of all points inside a polygon?
Imagine I have a polygon, which represents the countours of a building on an integer 3D map (everything is a 1 meter by 1 meter block in that map). In the image below, you see several buildings ...
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Travel planning - Finding farthest points of a polygon
I’d like to organize a tour around the lake with 2 objectives:
maximise the length of shores to view
minimise travel distance
In order to do so I can:
Pick 2 most remote points on the lake in ...
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How to compute Straight Skeletons using Python?
Is there a Python package which provides an implementation of a Straight Skeleton algorithm?
I'm aware that the open source (C++) project CGALcontains an implementation but it seems like cgal-...