triangulation

How is the camera coordinate system in OpenCV oriented?

走远了吗. 提交于 2019-11-27 21:33:41
I'm trying to get the 3D coordinate of a point from the triangulation of two view. I'm not really sure if my results are correct or not. For example I'm not really sure if the sign of the coordinates are correct because I'm not sure how the camera frame is orientated. The z axis positive verse is entering or exiting the image plane? And x and y? Do they follow the right hand rule? Thanks in advance for a clarification! The coordinate system is set according to the image and the description on this webpage 来源: https://stackoverflow.com/questions/17987465/how-is-the-camera-coordinate-system-in

Mesh to mesh intersections

白昼怎懂夜的黑 提交于 2019-11-27 21:00:36
问题 I'm looking for a library or a paper that describes how to determine if one triangular mesh intersects another. Interestingly I am coming up empty. If there is some way to do it in CGAL, it is eluding me. It seems like it clearly should be possible, because triangle intersection is possible and because each mesh contains a finite number of triangles. But I assume there must be a better way to do it than the obvious O(n*m) approach where one mesh has n triangles and the other has m triangles.

How does this code for delaunay triangulation work?

时间秒杀一切 提交于 2019-11-27 13:47:09
I have this Java code that with a set of Point in input return a set of graph's edge that represent a Delaunay triangulation. I would like to know what strategy was used to do this, if exist, the name of algorithm used. In this code GraphEdge contains two awt Point and represent an edge in the triangulation, GraphPoint extends Awt Point, and the edges of final triangulation are returned in a TreeSet object. My purpose is to understand how this method works: public TreeSet getEdges(int n, int[] x, int[] y, int[] z) below the complete source code of this triangulation : import java.awt.Point;

Trilateration and locating the point (x,y,z)

空扰寡人 提交于 2019-11-27 10:22:46
问题 I want to find the coordinate of an unknown node which lie somewhere in the space which has its reference distance away from 3 or more nodes which all of them have known coordinate. This problem is exactly like Trilateration as described here Trilateration. However, I don't understand the part about "Preliminary and final computations" (refer to the wikipedia site). I don't get where I could find P1, P2 and P3 just so I can put to those equation? Thanks 回答1: Trilateration is the process of

Wifi Triangulation

浪子不回头ぞ 提交于 2019-11-27 09:29:18
问题 What would be the best way to triangulate a wireless network passively. Are there tools available? Algorithms? Libraries? My goal would be to create a relative map of various objects that sends or receive signals using signal strength (DB's), signal/noise ratio, signal phase, etc. from a few location points. With enough sampling, i'm guessing it would be possible to create a good 2d/3d map. I'm searching for stuff in any language / platform. Some keywords: wi-fi site survey, visualization,

Wifi position triangulation

梦想的初衷 提交于 2019-11-27 09:07:13
问题 I need to understand how Wifi triangulation basically works. The scene is as portrayed in above diagram. Inorder to implement wifi triangulation, I need a minimum of 3 Wifi hotspots and their positions. The setup: 1. For simplicity, let's assume I have a 1 sq-Km by 1 sq-Km area, and I have 3 Wifi hotspots in this area. The coordinate system is as follows: 1 corner of the square area is (0,0,0), and the diagonally furthest corner will have coordinates (1,1,1). All position determination is to

Draw Quadratic Curve on GPU

走远了吗. 提交于 2019-11-27 08:57:22
My task is to render quadratic Bezier curve (path) via Stage3d (Adobe Flash) technology, which have no any extensions for that drawing out-of-the box (while OpenGl have it, as I know). Yea, there is a Starling-Extension-Graphics, but it uses simple method to divide a curve segment to many straight lines, that generates very many triangles for my long curve path. So.. There is a perfect way for rendering resolution independed shapes for Loop and Blinn. I've read GPUGems3 article (gpugems3_ch25.html) and ported that fragment shader to AGAL2: Quadratic Curve Pixel Shader float4 QuadraticPS(float2

Polygon Triangulation with Holes

一笑奈何 提交于 2019-11-27 06:08:54
I am looking for an algorithm or library (better) to break down a polygon into triangles. I will be using these triangles in a Direct3D application. What are the best available options? Here is what I have found so far: Ben Discoe's notes FIST: Fast Industrial-Strength Triangulation of Polygons I know that CGAL provides triangulation but am not sure if it supports holes. I would really appreciate some opinions from people with prior experience in this area. Edit: This is a 2D polygon. Jonathan Shewchuk's Triangle library is phenomenal; I've used it for automating triangulation in the past. You

How to correctly use cv::triangulatePoints()

▼魔方 西西 提交于 2019-11-27 03:21:21
I am trying to triangulate some points with OpenCV and I found this cv::triangulatePoints() function. The problem is that there is almost no documentation or examples of it. I have some doubts about it. What method does it use? I've making a small research about triangulations and there are several methods (Linear, Linear LS, eigen, iterative LS, iterative eigen,...) but I can't find which one is it using in OpenCV. How should I use it? It seems that as an input it needs a projection matrix and 3xN homogeneous 2D points. I have them defined as std::vector<cv::Point3d> pnts , but as an output

Is there C++ API for Delaunay triangulation in OpenCV?

安稳与你 提交于 2019-11-27 02:48:07
问题 I'm trying to implement one of active appearance models (AMM) and on one of the steps I need to get triangulated mesh of a face , e.g.: Delaunay triangulation seems to be a good fit for this task (correct me if there are better options), and OpenCV has C API for it. But is there C++ API for Delaunay triangulation? Of course if is not a big deal to write a wrapper for C version if there's really no C++ API, but it's possible that's just lack of my knowledge of API, and not the API itself. In