833 questions
4
votes
3
answers
286
views
Triangulating matrices using LU decomposition method in C : Question about for loop optimization
Matrices can be triangulated using less than ten lines of code in C, I have heard being said. But LU decomposition method needs to be used, instead of Cramer's rule. So, I was trying to do that. My ...
- 775
Advice
1
vote
2
replies
45
views
For a given list of normal vectors, I need a triangulation of the unit sphere such that its triangles' normals are the input normals
Is it even guaranteed that such a triangulation even exists for all expected list of normals? (It's easy to think of edge cases where it doesn't, in my case the normals will be composed of a long list ...
- 624
-5
votes
1
answer
115
views
Does the Google Geolocation API use triangulation or multilateration when multiple cell towers are provided?
I'm using the Google Maps Geolocation API to determine device location based on cellular data. The API allows submitting an array of cellTowers[] objects, each including fields like cellId, ...
- 1
2
votes
0
answers
31
views
Check using CGAL that a collection of simplices defines a valid triangulation
Let us assume that I have a collection of d-dimensional simplices in d dimension, each simplex being defined by its set of vertices (whose coordinates I have access to). d is strictly greater than 3.
...
0
votes
0
answers
180
views
Segmentation fault when using 'triangle' library ONLY when processing multiple geometries in loop
I am trying to process shapely polygon geometries and decompose them into triangles with the constraint that triangle vertices can only exist on the polygon edge(s).
For some strange reason the code ...
1
vote
1
answer
156
views
What are the units from cv2.triangulatePoints()?
I have a stereo camera system composed of two cameras placed perpendicular to each other but pointing at a common center. I have successfully camera calibrated each camera, and have also stereo ...
- 13
1
vote
3
answers
164
views
Minimizing and simplifying a 2D triangle mesh
Goal:
I have a list of lots of triangles on a 2D surface, represented as std::vector<QPolygonF>. I want to transform this list into another list of triangles that have the same outline, but no ...
- 30.5k
1
vote
0
answers
208
views
Structured light 3D scan: Triangulation using OpenCV in python delivers warped results
I'm trying to setup a 3D scanner using a single camera and a projector based on gray code structured light. The resulting pointclouds are heavily warped. ( see image below)
Warped point cloud
target ...
- 11
0
votes
1
answer
60
views
3D individual Delaunay cells that change color internally, depending on value of Z (or any other function)
I've got a 3D surface built on Delaunay triangulation. Do you know how to enforce matplotlib to paint each triangle not with a constant color but with a user-defined-function dependent color ? (or at ...
- 65
0
votes
1
answer
128
views
Computing surface Laplacian/Laplace Beltrami in R using Delaunay triangulation
I have been researching methods to compute the Laplacian/Laplace-Beltrami operator, but I've found that R lacks built functions for these purposes. There is actually a package that allows for ...
- 451
1
vote
2
answers
1k
views
How can I generate a concave hull of 3D points?
I have 68 3d points (I'm guessing it's called a sparse point cloud). I want to connect them all together to create a mesh. I first tried this using Delaunay Triangulation. However, it didn't work well ...
0
votes
1
answer
257
views
Meaning of mesh_size
In the following, does "mesh_size" refer to the maximum perimeter or maximum area of each element?
with pygmsh.geo.Geometry() as geom:
geom.add_polygon(
[
[0.0, 0.0],
...
- 101
1
vote
0
answers
130
views
I am trying to find car motions with two cameras on Carla but the results are meaningless
I have two cameras in a fixed position on the vehicle and the features of these cameras are exactly the same. First, I record an image with these two cameras, which I call "initial". Then, ...
- 11
0
votes
1
answer
350
views
Polygon Triangulation is not proper for some polygons using Delaunay Triangulation Method
My original polygon WKT is this:
POLYGON ((98.51786360976723 78.60265688535823, 98.51786360976723 78.67546052678281, 98.78608990953424 78.67546052678281, 98.78608990953424 78.60265688535823, 98....
0
votes
1
answer
454
views
xyz (latitude longitude elevation) position on a surface
how do I find a the xyz position on a surface created with multiple points. Say I survey the perimeter of a parking lot sloped in 2 directions not necessarily on a flat plan to create a surface. If i ...
- 1