triangulation

问题 I need to create a triangle mesh from a set of points. The set has very few points so it doesn't need to be fast or optimised (I will deal with 100 points maximum). The mesh needs to be a constrained "delaunay triangulation". In the image below I showed (on the left) the set of points I start from (blue and red dots). I also know the connections between these points (the outline in black). The mesh needs to look like the example on the right (including the edges in grey that form outside and

问题 After I've done a 2D triangulation, some triangles have the same color and I want to recombine them for drawing into like-colored graphics paths. I find that if I just draw the triangles one by one, some graphic renderers shows seams between the triangles (at least if anti-aliasing and/or transparency is involved). So how do I take a set of (non-overlapping) triangles and produce a graphics path, which may contain holes and disjoint polygons? Blindly adding the triangles to a graphics path

问题 Is there any headless browser that support geolocation? I know Phantomjs doesn't support that feature. If no, how programs that uses geolocation (prey project & lockit tight) work? I'm interested in client-side geolocation using WiFi positioning & triangulation. Can any moderator create a tag for WiPS (Wi-Fi Positioning System), if it's appropriate? 回答1: IP Geolocation using IP address done from server-side works for all headless browsers because it can retrieves user IP address instantly on

问题 I have problem similar to tripcolor demo example. I have lon,lat , z values which i am plotting using Tripcolor i want to show annotation as lon value,lat value and z value at particular lon,lat location if my z value is less than 0.70. For Example in below code , i want an annotation / popup message show in my plot which show lon value, lat value and z value at location lon=-2 lat=55 show annotation if z value is less than 0.70 i.e if zvalue is greater than 0.70 then in plot show me lon

问题 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

问题 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

问题 I'm facing a problem that I hope some others have faced before because I can't find a way out ! I have a regular triangulation in CGAL in which I wish to insert some weighted points with info std::pair<myweightpoint, myinfo> one by one and to get the handle to the vertex ( Vertex_handle ) once it is inserted ! The thing is that there is no such function. It exists several functions to insert : Vertex_handle Regular_triangulation::insert ( const Weighted_point & p ) ; That returns a Vertex

问题 In my Android application I'm willing to use GPS locations . What are the main permissions that I should included in android manifest file in order to use GPS locations. In case of lost the GPS signal strength, is there any way to triangulate the position using mobile networks. Thank you! 回答1: The main permissions you need are android.permission.ACCESS_COARSE_LOCATION or android.permission.ACCESS_FINE_LOCATION . Only fine location will allow you access to gps data, and allows you access to

问题 In my Android application I'm willing to use GPS locations . What are the main permissions that I should included in android manifest file in order to use GPS locations. In case of lost the GPS signal strength, is there any way to triangulate the position using mobile networks. Thank you! 回答1: The main permissions you need are android.permission.ACCESS_COARSE_LOCATION or android.permission.ACCESS_FINE_LOCATION . Only fine location will allow you access to gps data, and allows you access to

问题 I have been searching for an answer to this question but cannot find anything useful. I am working with the python scientific computing stack (scipy,numpy,matplotlib) and I have a set of 2 dimensional points, for which I compute the Delaunay traingulation (wiki) using scipy.spatial.Delaunay . I need to write a function that, given any point a , will return all other points which are vertices of any simplex (i.e. triangle) that a is also a vertex of (the neighbors of a in the triangulation).