polygon

问题 I have made a tetrahedron using vertex coordinates and line segments using the function plot3d() from the package {rgl}. The code below makes the mentioned plot library("rgl") CCl4=c(5,5,5,10) Luminol=c(0.01,0.001,0.005,0.005) Na2CO3=c(0.01,0.01,0.1,0.05) plot3d( Luminol, Na2CO3, CCl4, type = "s") for(i in 1:4){ for(k in 1:4){ segments3d(x=Luminol[c(i,k)],y=Na2CO3[c(i,k)],z=CCl4[c(i,k)]) } } Now, I want to fill the area between the points (preferably using a RGB color so I can define

问题 I have made a function who calculate area polygon with Shoelace way. That's works perfectly but right now I wonder if there is not a faster way to have the same result. I want to know that because this function must work faster with polygon with a lot of coordinates. My function : def shoelace_formula(polygonBoundary, absoluteValue = True): nbCoordinates = len(polygonBoundary) nbSegment = nbCoordinates - 1 l = [(polygonBoundary[i+1][0] - polygonBoundary[i][0]) * (polygonBoundary[i+1][1] +

问题 How can I access property of geojson data inside drawn polygon?I have this example: var map; function initMap() { map = new google.maps.Map(document.getElementById('map'), { zoom: 4, center: {lat: -28, lng: 137} }); // Load GeoJSON. map.data.loadGeoJson('https://storage.googleapis.com/mapsdevsite/json/google.json'); // Set the stroke width, and fill color for each polygon map.data.setStyle({ fillColor: 'green', strokeWeight: 1 }); var drawingManager = new google.maps.drawing.DrawingManager({

问题 How can i retrieve OR calculate the coordinates of the NW or SE corners of a Rectangle? I'm using Google Maps API v3 and I know there is the getBounds() method which returns the NE and SW coordinates of the rectangle. I need all four coordinates because KML 2.2 does not have a rectangle schema spec, it only has the polygon schema and i need to be able to export my rectangle into a kml as a polygon. 回答1: NW coordinates - (x1, y1) SE coordinates - (x2, y2) NE coordinates - (x2, y1) SW

问题 There is a collection of vertices: [ x1 y1 x2 y2 .. xn yn ] I would like to change the center of those coordinates. So I try: proc changeCenter { vertices X Y } { set myList [list] foreach element $vertices { lappend myList [expr [lindex $element 0] + $X] lappend myList [expr [lindex $element 1] + $Y] } return $myList } But its performance too slow. How can I change above code to be more effective or maybe need to change the representation of vertices? 回答1: Your changeCenter proc indicates

问题 I would like draw a filled polygon on iPhone with Google map (Version 1.1.1, the last one). Anyone knows how to do like that on ios : (My code on Android) mMap.addPolygon(new PolygonOptions() .addAll(latLngList) .fillColor(Color.BLUE) .strokeColor(Color.RED) .strokeWidth(3)); Regards, PS : If you have many solutions, keep in mind that I have many Polygon to draw. 回答1: The SDK currently doesn't support filled polygons, however there is a feature request to add them here: https://code.google

问题 i tried in that way but i didnt get the needed results: System.Drawing.Point[] p = new System.Drawing.Point[6]; p[0].X = 0; p[0].Y = 0; p[1].X = 53; p[1].Y = 111; p[2].X = 114; p[2].Y = 86; p[3].X = 34; p[3].Y = 34; p[4].X = 165; p[4].Y = 7; g = PictureBox1.CreateGraphics(); g.DrawPolygon(pen1, p); what i want to do is to draw a polygon in picturebox which is defined with diffrent colors and according to the rates (the number of corner and coordinates of the edges ) 回答1: Create an xOffset

问题 I've been struggling with this problem for a few days. I have a shapefile that contains zip code polygons. I'm trying to plot a certain portion of it with a transparent color ( alpha=0.7 ), but some of the polygons at the edge of the plot end up with no color. If alpha=1.0 , all polygons are fine. The shapefile is stored as a Large SpatialPolygonsDataFrame . # Code that you can use (Thanks jbaums) library(rgdal); download.file('http://www.naturalearthdata.com/http//www.naturalearthdata.com/do

问题 I have a map drawn using leaflet.js. If I give longitude and latitude value as input Can I identify the polygon? Can I get a client side script for this? 回答1: Got an answer as follows : //This is based on 'point in polygon algorithm' function getPoint () { float x=-89.82421875; //x and y represents the lat and lng values float y= 40.18307014852533; var a = boundaries; //the coordinates used to draw the map for (i = 0; i < a.features.length; i++) { PointInPolygon(x,y, a.features[i].geometry

问题 I am looking for an algorithm to generate equally distributed points inside a polygon. Here is the scenario: I have a polygon specified by the coordinates of the points at the corners (x, y) for each point. And I have the number of points to generate inside the polygon. For example lets say I have a polygon containing 5 points: (1, 1) ; (1, 2) ; (2, 3) ; (3, 2) ; and (3, 1) And I need to generate 20 equally distanced points inside that polygon. Note: Some polygons may not support equally