Add a layer clipping example

2013-11-13 09:03:27 +01:00
parent 2073d78582
commit b698c5bf7b
2 changed files with 93 additions and 0 deletions
--- a/examples/layer-clipping.html
+++ b/examples/layer-clipping.html
@@ -0,0 +1,50 @@
+<!doctype html>
+<html lang="en">
+  <head>
+    <meta charset="utf-8">
+    <meta http-equiv="X-UA-Compatible" content="chrome=1">
+    <meta name="viewport" content="initial-scale=1.0, user-scalable=no, width=device-width">
+    <link rel="stylesheet" href="../css/ol.css" type="text/css">
+    <link rel="stylesheet" href="../resources/bootstrap/css/bootstrap.min.css" type="text/css">
+    <link rel="stylesheet" href="../resources/layout.css" type="text/css">
+    <link rel="stylesheet" href="../resources/bootstrap/css/bootstrap-responsive.min.css" type="text/css">
+    <title>Layer clipping example</title>
+  </head>
+  <body>
+
+    <div class="navbar navbar-inverse navbar-fixed-top">
+      <div class="navbar-inner">
+        <div class="container">
+          <a class="brand" href="./"><img src="../resources/logo.png"> OpenLayers 3 Examples</a>          
+        </div>
+      </div>
+    </div>
+
+    <div class="container-fluid">
+
+      <div class="row-fluid">
+        <div class="span12">
+          <div id="map" class="map"></div>
+        </div>
+      </div>
+
+      <div class="row-fluid">
+
+        <div class="span12">
+          <h4 id="title">Layer clipping example</h4>
+          <p id="shortdesc">Layer clipping example.</p>
+          <div id="docs">
+            <p>See the <a href="layer-clipping.js" target="_blank">layer-clipping.js source</a> to see how this is done.</p>
+          </div>
+          <div id="tags">clipping, openstreetmap</div>
+        </div>
+
+      </div>
+
+    </div>
+
+    <script src="loader.js?id=layer-clipping" type="text/javascript"></script>
+    <script src="../resources/example-behaviour.js" type="text/javascript"></script>
+
+  </body>
+</html>
--- a/examples/layer-clipping.js
+++ b/examples/layer-clipping.js
@@ -0,0 +1,43 @@
+goog.require('ol.Map');
+goog.require('ol.RendererHints');
+goog.require('ol.View2D');
+goog.require('ol.layer.Tile');
+goog.require('ol.source.OSM');
+
+var osm = new ol.layer.Tile({
+  source: new ol.source.OSM()
+});
+
+var map = new ol.Map({
+  layers: [osm],
+  renderer: ol.RendererHint.CANVAS,
+  target: 'map',
+  view: new ol.View2D({
+    center: [0, 0],
+    zoom: 2
+  })
+});
+
+osm.on('precompose', function(event) {
+  var ctx = event.getContext();
+  var size = event.getFrameState().size;
+  ctx.save();
+  ctx.translate(size[0] / 2, size[1] / 2);
+  ctx.scale(3, 3);
+  ctx.translate(-75, -80);
+  ctx.beginPath();
+  ctx.moveTo(75, 40);
+  ctx.bezierCurveTo(75, 37, 70, 25, 50, 25);
+  ctx.bezierCurveTo(20, 25, 20, 62.5, 20, 62.5);
+  ctx.bezierCurveTo(20, 80, 40, 102, 75, 120);
+  ctx.bezierCurveTo(110, 102, 130, 80, 130, 62.5);
+  ctx.bezierCurveTo(130, 62.5, 130, 25, 100, 25);
+  ctx.bezierCurveTo(85, 25, 75, 37, 75, 40);
+  ctx.clip();
+  ctx.setTransform(1, 0, 0, 1, 0, 0);
+});
+
+osm.on('postcompose', function(event) {
+  var ctx = event.getContext();
+  ctx.restore();
+});