openlayers/examples/resize-features.html

   1 <html xmlns="http://www.w3.org/1999/xhtml">
   2   <head>
   3     <title>OpenLayers Resize Features Example</title>
   4     <link rel="stylesheet" href="../theme/default/style.css" type="text/css" />
   5     <link rel="stylesheet" href="style.css" type="text/css" />
   6     <style type="text/css">
   7         p {
   8             width: 500px;
   9         }
  10     </style>
  11     <script src="../lib/OpenLayers.js"></script>
  12     <script type="text/javascript">
  13         var map, vectorLayer, pointFeature, lineFeature, polygonFeature;
  14
  15         function init(){
  16             map = new OpenLayers.Map('map');
  17             var layer = new OpenLayers.Layer.WMS( "OpenLayers WMS",
  18                     "http://labs.metacarta.com/wms/vmap0", {layers: 'basic'} );
  19             map.addLayer(layer);
  20
  21             var style_blue = OpenLayers.Util.extend({}, OpenLayers.Feature.Vector.style['default']);
  22             style_blue.strokeColor = "blue";
  23             style_blue.fillColor = "blue";
  24             var style_green = {
  25                 strokeColor: "#339933",
  26                 strokeOpacity: 1,
  27                 strokeWidth: 3,
  28                 pointRadius: 6,
  29                 pointerEvents: "visiblePainted"
  30             };
  31
  32             vectorLayer = new OpenLayers.Layer.Vector("Simple Geometry");
  33
  34             // create a point feature
  35             var point = new OpenLayers.Geometry.Point(-110, 45);
  36             pointFeature = new OpenLayers.Feature.Vector(point, null, style_blue);
  37
  38             // create a line feature from a list of points
  39             var pointList = [];
  40             var newPoint = point;
  41             for(var p=0; p<5; ++p) {
  42                 newPoint = new OpenLayers.Geometry.Point(newPoint.x + Math.random(1),
  43                                                          newPoint.y + Math.random(1));
  44                 pointList.push(newPoint);
  45             }
  46             lineFeature = new OpenLayers.Feature.Vector(
  47                 new OpenLayers.Geometry.LineString(pointList),null,style_green);
  48
  49             // create a polygon feature from a linear ring of points
  50             var pointList = [];
  51             for(var p=0; p<6; ++p) {
  52                 var a = p * (2 * Math.PI) / 7;
  53                 var r = Math.random(1) + 1;
  54                 var newPoint = new OpenLayers.Geometry.Point(point.x + (r * Math.cos(a)),
  55                                                              point.y + (r * Math.sin(a)));
  56                 pointList.push(newPoint);
  57             }
  58             pointList.push(pointList[0]);
  59
  60             var linearRing = new OpenLayers.Geometry.LinearRing(pointList);
  61             polygonFeature = new OpenLayers.Feature.Vector(
  62                 new OpenLayers.Geometry.Polygon([linearRing]));
  63
  64
  65             map.addLayer(vectorLayer);
  66             map.setCenter(new OpenLayers.LonLat(point.x, point.y), 5);
  67             vectorLayer.addFeatures([pointFeature, lineFeature, polygonFeature]);
  68
  69         }
  70
  71         var origin = new OpenLayers.Geometry.Point(-111.04, 45.68);
  72         function resizeFeatures(scale) {
  73             pointFeature.geometry.resize(scale, origin);
  74             lineFeature.geometry.resize(scale, origin);
  75             polygonFeature.geometry.resize(scale, origin);
  76             vectorLayer.redraw();
  77         }
  78
  79     </script>
  80   </head>
  81   <body onload="init()">
  82     <h3 id="title">Resize Features Programatically</h3>
  83     <p id="shortdesc">
  84       Demonstration of how to use the geometry resize methods to
  85       change feature sizes programatically.
  86     </p>
  87     <div id="map" class="smallmap"></div>
  88     <p>This example demonstrates how features can be resized.  There is not yet
  89     a control built that provides a tool for resizing, but the geometry.resize
  90     method can be accessed to resize programmatically.</p>
  91     <p>Make the features <a href="javascript: resizeFeatures(1.5);">bigger</a>
  92     or <a href="javascript: resizeFeatures(1 / 1.5);">smaller</a>.
  93   </body>
  94 </html>