polygon

问题 There is a polygon and I am wondering how can I change color of particular edge of it like figure below. import matplotlib.pyplot as plt import numpy as np ## -----------------------Initialize Geometry----------------------- pixels = 600 my_dpi = 100 coord = [[-150,-200],[300,-200],[300,0],[150,200],[-150,200]] fig = plt.figure(figsize=( pixels/my_dpi, pixels/my_dpi), dpi=my_dpi) plt.axes([0,0,1,1]) rectangle = plt.Rectangle((-300, -300), 600, 600, fc='k') plt.gca().add_patch(rectangle)

问题 There is a polygon and I am wondering how can I change color of particular edge of it like figure below. import matplotlib.pyplot as plt import numpy as np ## -----------------------Initialize Geometry----------------------- pixels = 600 my_dpi = 100 coord = [[-150,-200],[300,-200],[300,0],[150,200],[-150,200]] fig = plt.figure(figsize=( pixels/my_dpi, pixels/my_dpi), dpi=my_dpi) plt.axes([0,0,1,1]) rectangle = plt.Rectangle((-300, -300), 600, 600, fc='k') plt.gca().add_patch(rectangle)

问题 There is a polygon and I am wondering how can I change color of particular edge of it like figure below. import matplotlib.pyplot as plt import numpy as np ## -----------------------Initialize Geometry----------------------- pixels = 600 my_dpi = 100 coord = [[-150,-200],[300,-200],[300,0],[150,200],[-150,200]] fig = plt.figure(figsize=( pixels/my_dpi, pixels/my_dpi), dpi=my_dpi) plt.axes([0,0,1,1]) rectangle = plt.Rectangle((-300, -300), 600, 600, fc='k') plt.gca().add_patch(rectangle)

问题 How to add an polygon to a SpatialPolygonsDataFrame? Example: The script underneath will create a SpatialPolygonsDataFrame. I would like to add a polygon which consists of a large square around the existing polygons. library(rgdal) dsn <- system.file("vectors", package = "rgdal")[1] Scotland <- readOGR(dsn=dsn , layer="scot_BNG") plot(Scotland) Preferred end result: It is important that the rectangle becomes part of the SpatialPolygonsDataFrame. Since I have to do some calculation of the

问题 When I call "GL11.glEnd" the polygon disappears. If I leave that one line "GL11.glEnd" out, then it stays on the screen, but when I put it in, the polygon I was drawing disappears. package package01; import org.lwjgl.opengl.GL11; public class Graph { ... void initGraph(){ GL11.glClearColor(0.0f, 0.0f, 0.0f, 0.0f); GL11.glClearDepth(1.0); GL11.glClear(GL11.GL_COLOR_BUFFER_BIT | GL11.GL_DEPTH_BUFFER_BIT); GL11.glOrtho(-500, 500, -281, 281, -1, 1); GL11.glColor3f(0.8f, 0.8f, 1.0f); GL11.glBegin

问题 I am trying to solve the following problem in R : I have a polygon object defined by a list l with two components x and y. The order defines the edges of the polygon. For instance : l=list( x=c(-1.93400738955091,0.511747161547164,1.85047596846401,-1.4963460488281,-1.31613255558929,-0.0803828876660542,1.721752044722,-0.724002506376074,-2.08847609804132,2.13366860069641), y=c(-1.02967154136169,1.53216851658359,-1.39564869249673,-1.21266011692921,1.6419616619241,-1.87141898897228,0

问题 Ok, so I have a polygon (simple but concave) that I'm trying to cut into triangles to make it collide with an other polygon. I knew my polygone was concave, so i decided to use LibGDX EarClippingTriangulator to manage to cut it into triangles. So, with this code, I get my triangles vertices : public void triangulate() { Vector<float[]> trianglesVertices = new Vector<float[]>(); ShortArray pointsCoords = new ShortArray(); EarClippingTriangulator triangulator = new EarClippingTriangulator(); //

问题 I'm trying to redo a client site that's currently not responsive and throughout the site she has long images that are trapezoids with text inside. Of course, on devices, you can barely read it. So I'm trying to turn it into CSS using shapes. Tried a bunch of examples but nothing working at the moment. I think the difference is the examples seem to use hard width numbers instead of 100% for fluid width. I have a pen here: https://codepen.io/anon/pen/KmgoqE and here's the code I'm playing with

问题 Summary: I thought that using gCentroid in R would return the centroid of a group of points, however I realised that for some reason it actually returns the geometric mean and not the centroid I wanted to replicate a centroid calculation I did in R: gCentroid {rgeos} The centre of mass of these points: 34.7573, -86.678606 38.30088, -76.520266 38.712147, -77.158616 39.704905, -84.126463 ... using the r-script ... require(rgdal) require(rgeos) no_am_eq_co <- "+proj=eqdc +lat_0=0 +lon_0=0 +lat_1

问题 i try to draw a polygon with the mouse , and i have found that example on jsfiddle: http://jsfiddle.net/Kienz/ujefxh7w/. the problem is that when we finish the draw and try to selet the object, the borders are outside of the shape. can we fixe that or is it a fabric.js bug? as we can also see on the official fabricjs.com/ page, on the front page examples, the free hand drawings are also out of the border frame. // initialize fabric canvas and assign to global windows object for debug var