Divide the draw features example into two examples

2016-10-16 16:38:00 -06:00
parent ec1ad89338
commit ac805e804b
4 changed files with 115 additions and 37 deletions
@@ -0,0 +1,86 @@
+goog.require('ol.Map');
+goog.require('ol.View');
+goog.require('ol.geom.Polygon');
+goog.require('ol.interaction.Draw');
+goog.require('ol.layer.Tile');
+goog.require('ol.layer.Vector');
+goog.require('ol.source.OSM');
+goog.require('ol.source.Vector');
+
+var raster = new ol.layer.Tile({
+  source: new ol.source.OSM()
+});
+
+var source = new ol.source.Vector({wrapX: false});
+
+var vector = new ol.layer.Vector({
+  source: source
+});
+
+var map = new ol.Map({
+  layers: [raster, vector],
+  target: 'map',
+  view: new ol.View({
+    center: [-11000000, 4600000],
+    zoom: 4
+  })
+});
+
+var typeSelect = document.getElementById('type');
+
+var draw; // global so we can remove it later
+function addInteraction() {
+  var value = typeSelect.value;
+  if (value !== 'None') {
+    var geometryFunction;
+    if (value === 'Square') {
+      value = 'Circle';
+      geometryFunction = ol.interaction.Draw.createRegularPolygon(4);
+    } else if (value === 'Box') {
+      value = 'Circle';
+      geometryFunction = ol.interaction.Draw.createBox();
+    } else if (value === 'Star') {
+      value = 'Circle';
+      geometryFunction = function(coordinates, geometry) {
+        if (!geometry) {
+          geometry = new ol.geom.Polygon(null);
+        }
+        var center = coordinates[0];
+        var last = coordinates[1];
+        var dx = center[0] - last[0];
+        var dy = center[1] - last[1];
+        var radius = Math.sqrt(dx * dx + dy * dy);
+        var rotation = Math.atan2(dy, dx);
+        var newCoordinates = [];
+        var numPoints = 12;
+        for (var i = 0; i < numPoints; ++i) {
+          var angle = rotation + i * 2 * Math.PI / numPoints;
+          var fraction = i % 2 === 0 ? 1 : 0.5;
+          var offsetX = radius * fraction * Math.cos(angle);
+          var offsetY = radius * fraction * Math.sin(angle);
+          newCoordinates.push([center[0] + offsetX, center[1] + offsetY]);
+        }
+        newCoordinates.push(newCoordinates[0].slice());
+        geometry.setCoordinates([newCoordinates]);
+        return geometry;
+      };
+    }
+    draw = new ol.interaction.Draw({
+      source: source,
+      type: /** @type {ol.geom.GeometryType} */ (value),
+      geometryFunction: geometryFunction
+    });
+    map.addInteraction(draw);
+  }
+}
+
+
+/**
+ * Handle change event.
+ */
+typeSelect.onchange = function() {
+  map.removeInteraction(draw);
+  addInteraction();
+};
+
+addInteraction();