How can I check if a coordinates (x,y) belong to a triangle with vertices coordinates v1, v2, v3?
How can I open both of them on the same figure to see the overlapping between the triangulation mesh with the image? in Matlab
Related
Is it possible to extract the coordinate of surface vertices in the fimplicit3 function in Matlab?
Couldn't found how to do with fimplicit3, but it easier to extract vertices and faces from a surface using isosurface function.
One can follow this tutorial: Implicit curves and surfaces sith Isosurface
I have a workspace containing a polyhedral shape so I sliced the workspace into different 3D circles. For each circle, it is either there occurs an intersection with the polyhedral or not. Is it possible to determine if the circle intersects with the polyhedron in MATLAB and if yes, how can I determine the polygon formed by the intersection of a 3d circle with a polyhedral shape?
NB: 3D circle is a circular shaped object in the 3D space. For ease of understanding, I have attached a MATLAB plot:
There are 3 circles and four polyhedral shapes in the plot.
Any help will be appreciated
I have a number of 2D points x and y, and I need to color delaunay triangles, which have edges that exceed a certain limit. However I can't figure out how to write it down so that it would compare each edge of each triangle and add it to a vector of triangles that need to be patched. The end result is supposed to be a 3D surface, where color depends on the Z coordinate, except for the triangles that have been patched white. Any help would be great!
You can try a contour plot. With your triangles and z values find the average of each triangle.
How to find out distance between point along the surface from one point to all other point on the cylinder surface.
XYZ coordinates of points are known
e.g
suppose 4 points are there on the surface of the cylinder here i want to find out following data i.e distance between point(1-2),point(1-3),point(1-4),point(2-3),point(2-4),point(3,4) along the surface.H
What you are looking for is the geodesic of a cylinder. Since you mentioned Matlab in the tag, you can use this tool
I write my study and is stuck when i try triangulate the contour of surface. When it is in 2D its ok. When it in 3D a have trouble with triangle angle detection, i tried with:
Triange have 3 Vertices v1,v2,v3
I create 2 vectors(vec21, vec23) from v2v1 and v2v3
then vec21 x vec23 and obtain a det of matrix
on the stand which I define Span angle
I also check if edges do not crossing and if any point isnt in area of triangle.
But when it in 3D i choose point around polygon then this metod didn't work
Points of contour i want triangulate to flat polygon: https://docs.google.com/open?id=0Bw5-VXnqutXBckRJMGNJMW9JaXc
Bad resoult: https://docs.google.com/open?id=0Bw5-VXnqutXBMzV5elIxX1FaeDQ
In 2d:
Points on 2D :https://docs.google.com/open?id=0Bw5-VXnqutXBWVE4bWJsZ09mOVk
Good resoults:https://docs.google.com/open?id=0Bw5-VXnqutXBdGFKM2Z4UnFRdXc
Where i made mistake? Can u explain me this?
Greetings!
PS. Im interested in algoithm at 2 last case:http://www.cosy.sbg.ac.at/~held/projects/triang/triang.html
Typically one would use a Delaunay Triangulation for the 2D case. For the 3D case you can project the points to 2D, triangulate and project the triangles back to 3D. This will of course only work if the patch to be triangulated can be projected to 2D (without selfintersections).