intersection

C++ library for mesh to mesh intersection: what is available?

冷暖自知 提交于 2019-11-28 04:25:11
问题 I need to calculate volume intersection and penetration depth between 3D triangular meshes (e.g. in .obj format), but I am quite new to computational geometry. In a previous post (Mesh to mesh intersections) and from my google search, I found a few C++ libraries which might be appropriate to do the job: CGAL PQP libigl SWIFT Though, I am not sure which one could be the most appropriate for a beginner. Any suggestion? 回答1: libigl as of version 1.1 has robust mesh boolean operations in igl

MongoDb use filter to match a list

蓝咒 提交于 2019-11-28 02:19:15
I have a list of BsonDocument : var list = db.GetCollection<BsonDocument>(collectionName); var myIds = list.Find(_ => true) .Project(Builders<BsonDocument>.Projection.Include("_id")) .ToList(); that contains: myIds = "{ { "_id" : "cc9d9282-c9d2-4cba-a776-ffddsds274d5" }, { "_id" : "2c1ddd82-c9d2-4dda-afr6-d79ff1274d56" }, { "_id" : "ss969281-c9d2-4cba-a776-d79ffds274d5" } }" And want to query like this: var deleted =list.DeleteMany(Builders<MessageExchange>.Filter.In("_id", myIds)); I also have tried the following: var filter = new BsonDocument("_id", new BsonDocument("$in", new BsonArray

How to check intersection between a line and a rectangle?

让人想犯罪 __ 提交于 2019-11-28 00:11:06
问题 The title says it all, Ive been searching around and couldnt find anything that was straight and to the point. How would I take a line with points (x1,y1) & (x2, y2) and check its intersection between a rectangle (xR,yR)? I saw in the Line2D package that there were some intersection methods but not sure how to set it all up. Can someone show me a correct way of setting it up to check for an intersection (collision)? 回答1: Using the available classes from the 2D Graphics API. Rectangle r1 = new

Python - matplotlib: find intersection of lineplots

我是研究僧i 提交于 2019-11-27 20:41:23
I have a probably simple question, that keeps me going already for quiet a while. Is there a simple way to return the intersection of two plotted (non-analytical) datasets in python matplotlib ? For elaboration, I have something like this: x=[1.4,2.1,3,5.9,8,9,23] y=[2.3,3.1,1,3.9,8,9,11] x1=[1,2,3,4,6,8,9] y1=[4,12,7,1,6.3,8.5,12] plot(x1,y1,'k-',x,y,'b-') The data in this example is totaly arbitrary. I would now like to know if there is a simple build in function that I keep missing, that returns me the precise intersections between the two plots. Hope I made myself clear, and also that I

Java 8 Lambda - Intersection of Two Lists

强颜欢笑 提交于 2019-11-27 19:37:39
I am trying to find intersection of two lists based on some condition and doing some steps. Couldn't find a way to do it (in learning stage) :) Double totalAmount = 0.00d; Double discount = 0.00d; List<OrderLineEntry> orderLineEntryList = orderEntry.getOrderReleases().stream() .flatMap(orderReleaseEntry -> orderReleaseEntry.getOrderLines().stream()) .filter(orderLineEntry -> orderLineEntry.getStatus().equals("PP") || orderLineEntry.getStatus().equals("PD")) .collect(Collectors.toList()); for (OrderLineEntry orderLineEntry : orderLineEntryList) { for (SplitLineEntry splitLineEntry :

Calculation of intersections between line segments

六眼飞鱼酱① 提交于 2019-11-27 19:28:07
There's a lot of questions about intersections between line segments here at stackowerflow and here is one more! Sorry, but I need help to understand how to calculate intersections. I have read several of the questions here and looked at several examples on other websites, but I'm still confused and don't get it! I don't like to copy and paste code without how things work. So far I know that I'm going to compare the points of each line segments like Ax, Ay, Bx, By, Cx, Cy, Dx, Dy. Could someone explain for me what I'm going to calculate, what would the result of the calculating be if there is

Show the intersection of two curves

懵懂的女人 提交于 2019-11-27 19:11:07
问题 If I have two plots defined by two different equations: x = 0:0.01:30; y1 = x .^2 + 2; y2 = x .^3 ; and I plot them as plot(x, y1, x, y2); How do I get a small ring around the point of intersection programatically (as in the following plot)? 回答1: You'll have to find the point of intersection (p x , p y ) manually: idx = find(y1 - y2 < eps, 1); %// Index of coordinate in array px = x(idx); py = y1(idx); Remember that we're comparing two numbers in floating point representation, so instead of

Testing whether a line segment intersects a sphere

。_饼干妹妹 提交于 2019-11-27 18:54:28
问题 I am trying to determine whether a line segment (i.e. between two points) intersects a sphere. I am not interested in the position of the intersection, just whether or not the segment intersects the sphere surface. Does anyone have any suggestions as to what the most efficient algorithm for this would be? (I'm wondering if there are any algorithms that are simpler than the usual ray-sphere intersection algorithms, since I'm not interested in the intersection position) 回答1: I don't know what

Checking if two cubic Bézier curves intersect

末鹿安然 提交于 2019-11-27 17:43:14
For a personal project, I'd need to find out if two cubic Bézier curves intersect. I don't need to know where: I just need to know if they do. However, I'd need to do it fast. I've been scavenging the place and I found several resources. Mostly, there's this question here that had a promising answer. So after I figured what is a Sylvester matrix , what is a determinant , what is a resultant and why it's useful , I thought I figured how the solution works. However, reality begs to differ, and it doesn't work so well. Messing Around I've used my graphing calculator to draw two Bézier splines

Test if two lines intersect - JavaScript function

旧街凉风 提交于 2019-11-27 17:37:56
I've tried searching for a javascript function that will detect if two lines intersect each other. The function will take the x,y values of both the start end points for each line (we'll call them line A and line B). Is to return true if they intersect, otherwise false. Example of the function. I'm happy if the answer uses a vector object instead. Function isIntersect (lineAp1x, lineAp1y, lineAp2x, lineAp2y, lineBp1x, lineBp1y, lineBp2x, lineBp2y) { // JavaScript line intersecting test here. } Some background info: this code is for a game I'm trying to make in html5 canvas, and is part of my