Add example for symbols in an atlas

2014-11-12 17:13:38 +01:00
parent 62e9d259b2
commit 7e9dd65f8b
2 changed files with 152 additions and 0 deletions
--- a/examples/symbol-atlas-webgl.js
+++ b/examples/symbol-atlas-webgl.js
@@ -0,0 +1,100 @@
+goog.require('ol.Feature');
+goog.require('ol.Map');
+goog.require('ol.View');
+goog.require('ol.geom.Point');
+goog.require('ol.layer.Vector');
+goog.require('ol.source.Vector');
+goog.require('ol.style.AtlasManager');
+goog.require('ol.style.Circle');
+goog.require('ol.style.Fill');
+goog.require('ol.style.Stroke');
+goog.require('ol.style.Style');
+
+var atlasManager = new ol.style.AtlasManager({
+  maxSize: ol.has.WEBGL_MAX_TEXTURE_SIZE});
+
+var symbolInfo = [{
+  opacity: 1.0,
+  scale: 1.0,
+  fillColor: 'rgba(255, 153, 0, 0.4)',
+  strokeColor: 'rgba(255, 204, 0, 0.2)'
+}, {
+  opacity: 0.75,
+  scale: 1.25,
+  fillColor: 'rgba(70, 80, 224, 0.4)',
+  strokeColor: 'rgba(12, 21, 138, 0.2)'
+}, {
+  opacity: 0.5,
+  scale: 1.5,
+  fillColor: 'rgba(66, 150, 79, 0.4)',
+  strokeColor: 'rgba(20, 99, 32, 0.2)'
+}, {
+  opacity: 1.0,
+  scale: 1.0,
+  fillColor: 'rgba(176, 61, 35, 0.4)',
+  strokeColor: 'rgba(145, 43, 20, 0.2)'
+}];
+
+var radiuses = [3, 6, 9, 15, 19, 25];
+var symbolCount = symbolInfo.length * radiuses.length;
+var symbols = [];
+var i, j;
+for (i = 0; i < symbolInfo.length; ++i) {
+  var info = symbolInfo[i];
+  for (j = 0; j < radiuses.length; ++j) {
+    symbols.push(new ol.style.Circle({
+      opacity: info.opacity,
+      scale: info.scale,
+      radius: radiuses[j],
+      fill: new ol.style.Fill({
+        color: info.fillColor
+      }),
+      stroke: new ol.style.Stroke({
+        color: info.strokeColor,
+        width: 1
+      }),
+      // by passing the atlas manager to the symbol,
+      // the symbol will be added to an atlas
+      atlasManager: atlasManager
+    }));
+  }
+}
+
+var featureCount = 30000;
+var features = new Array(featureCount);
+var feature, geometry;
+var e = 25000000;
+for (i = 0; i < featureCount; ++i) {
+  geometry = new ol.geom.Point(
+      [2 * e * Math.random() - e, 2 * e * Math.random() - e]);
+  feature = new ol.Feature(geometry);
+  feature.setStyle(
+      new ol.style.Style({
+        image: symbols[i % (symbolCount - 1)]
+      })
+  );
+  features[i] = feature;
+}
+
+var vectorSource = new ol.source.Vector({
+  features: features
+});
+var vector = new ol.layer.Vector({
+  source: vectorSource
+});
+
+// Use the "webgl" renderer by default.
+var renderer = exampleNS.getRendererFromQueryString();
+if (!renderer) {
+  renderer = 'webgl';
+}
+
+var map = new ol.Map({
+  renderer: renderer,
+  layers: [vector],
+  target: document.getElementById('map'),
+  view: new ol.View({
+    center: [0, 0],
+    zoom: 3
+  })
+});