triangulation

Can I run GLU (OpenGL) on a headless server?

为君一笑 提交于 2019-12-04 01:52:21
we're trying to use GLU's tesselation functions on a headless, GNU/linux server. We'd like to use PyOpenGL for that, but the problem is that it crashes on a call to gluNewTess (Segmentation fault) gdb backtrace says it's in glGetError, that makes me think that GLU tesselation needs a GL context? Or is it just some intricacy in PyOpenGL? I tried to find some information on how to initialize GL context on a headless (and virtualized) machine, no luck. Any information on these topics is appreciated. easiest: Xvfb :5 -screen 0 800x600x24 & export DISPLAY=:5 glxgears instead of glxgears, replace

Regularly spaced orthogonal grid Delaunay triangulation (Computing the paraboloid coeficients)

巧了我就是萌 提交于 2019-12-03 20:20:49
I'm trying to construct a Delaunay triangulation for the very specific case where the input x and y coordinates are orthogonal and relatively equidistant. Given the data size is relatively large (1000x1200 triangulation points) and that the Qhull algorithm doesn't know about my extra orthogonal condition, the triangulation is relatively slow (25 seconds on my machine). As such, I'd like to manually construct a Delaunay triangulation with each of my known quads subdivided into two triangles. I appreciate that this won't always result in a valid Delaunay triangulation (e.g. when the x and y step

Rotation and Translation from Essential Matrix incorrect

ぃ、小莉子 提交于 2019-12-03 16:09:12
I currently have a stereo camera setup. I have calibrated both cameras and have the intrinsic matrix for both cameras K1 and K2 . K1 = [2297.311, 0, 319.498; 0, 2297.313, 239.499; 0, 0, 1]; K2 = [2297.304, 0, 319.508; 0, 2297.301, 239.514; 0, 0, 1]; I have also determined the Fundamental matrix F between the two cameras using findFundamentalMat() from OpenCV. I have tested the Epipolar constraint using a pair of corresponding points x1 and x2 (in pixel coordinates) and it is very close to 0 . F = [5.672563368940768e-10, 6.265600996978877e-06, -0.00150188302445251; 6.766518121363063e-06, 4

C++-ObjC OpenCV Constrained Delaunay

喜欢而已 提交于 2019-12-03 14:06:51
问题 I succesfully implemented a Delaunay triangulation of a contour in OpenCV 2.3.1. With cvPointPolygonTest I can get all the triangles in the convex hull, then I tried to perform another cvPointPolygonTest on triangles centroid to know if they are in the main contour or not , so I can have the constrained triangulation of the contour. But, it doesn't work well, as some triangles are (eg. with a walking man who has his two legs distant) 'over' a hole . Does anyone know a way to perform a

how can i get the camera projection matrix out of calibrateCamera() return values

99封情书 提交于 2019-12-03 12:42:03
I am trying to get a 3x4 camera matrix for triangulation process but calibrateCamera() returns only 3x3 and 4x1 matrices. How can i get the 3x4 out of those matrices? Thanks in advance!! calibrateCamera() returns you a 3x3 matrix as cameraMatrix, a 4x1 matrix as distCoeffs, and rvecs and tvecs that are vectors of 3x1 rotation(R) and 3x1 transformation(t) matrices. What you want is ProjectionMatrix, which is multiply [cameraMatrix] by [R|t]. Therefore, it returs you a 3x4 ProjectionMatrix. You can read OpenCV documentation for more info. If you are using cameraCalibrate(), you must be getting

python scipy Delaunay plotting point cloud

Deadly 提交于 2019-12-03 07:07:40
I have a pointlist=[p1,p2,p3...] where p1 = [x1,y1],p2=[x2,y2] ... I want to use scipy.spatial.Delaunay to do trianglation on these point clouds and then plot it How can i do this ? The documentation for the Delaunay is really scarce so far i have this code from subprocess import Popen, PIPE import os os.environ['point_num'] = "2000" cmd = 'rbox $point_num D2 | tail -n $point_num' sub_process = Popen(cmd, shell=True,stdout=PIPE,stderr=PIPE) output = sub_process.communicate() points = [line.split() for line in output[0].split('\n') if line] x = [p[0] for p in points if p] y = [p[1] for p in

How to triangulate polygons in Boost?

我们两清 提交于 2019-12-03 06:44:58
What is the best way to triangulate a polygon with Boost? I use Boost.polygon . My current algorithm: Compute a voronoï diagram from my polygon vertices. Create one directed polygon-edge for each cell-edge (this will create two directed polygon edge per cell-edge) Iterate over all created edges to create triangles (not trivial) Any better solution? Edit: I just realized that it is probably possible to walk through the cells in a special way to create the triangles directly (3 neighbor cells create a triangle). Giovanni Funchal The main idea is to iterate through the Voronoi vertices, and

Calculating distance within a building

為{幸葍}努か 提交于 2019-12-03 05:19:51
问题 I started doing some thinking about creating an Android application that can be used within a corporate building to determine what room you are in. Obviously I'm thinking GPS and network locations wouldn't be accurate enough to accomplish this. (Not to mention the instability of GPS signal inside) I looked briefly into calculating distance via the accelerometer, but it is apparently highly volatile and leaves a large margin for error. I've also considered some sort of triangulation from

Efficient Delaunay triangulation

点点圈 提交于 2019-12-03 04:06:59
问题 I'm looking for a .NET implementation which builds Delaunay triangulation from set of points. I have already tested couple of implementations but they all worked only for small amount of points (up to 20,000). I need something that can handle 500,000 points in reasonable time. 回答1: If you want to construct the 2D Delaunay triangulation, use Triangle.Net . It is a direct C# port of Shewchuk's famous Triangle program. 回答2: I was looking for the same thing and I found a C# 4.0 library called

C++-ObjC OpenCV Constrained Delaunay

坚强是说给别人听的谎言 提交于 2019-12-03 04:04:21
I succesfully implemented a Delaunay triangulation of a contour in OpenCV 2.3.1. With cvPointPolygonTest I can get all the triangles in the convex hull, then I tried to perform another cvPointPolygonTest on triangles centroid to know if they are in the main contour or not , so I can have the constrained triangulation of the contour. But, it doesn't work well, as some triangles are (eg. with a walking man who has his two legs distant) 'over' a hole . Does anyone know a way to perform a constrained triangulation. I thought about convexityDefects, but can't manage to understand how to begin with