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<!DOCTYPE html>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=0">
<meta name="apple-mobile-web-app-capable" content="yes">
<title>Snapping</title>
<link rel="stylesheet" href="../theme/default/style.css" type="text/css">
<!--[if lte IE 6]>
<link rel="stylesheet" href="../theme/default/ie6-style.css" type="text/css" />
<![endif]-->
<link rel="stylesheet" href="style.css" type="text/css">
<style type="text/css">
.olControlEditingToolbar .olControlModifyFeatureItemInactive {
background-position: -1px -1px;
}
.olControlEditingToolbar .olControlModifyFeatureItemActive {
background-position: -1px -24px;
}
table {
padding: 1em 0 1em;
}
td {
padding: 0.5em 1em;
border: 1px solid #ddd;
}
tr.head td {
text-align: center;
font-weight: bold;
}
</style>
<script src="../lib/Firebug/firebug.js"></script>
<script src="../lib/OpenLayers.js"></script>
<script type="text/javascript">
OpenLayers.Feature.Vector.style['default']['strokeWidth'] = '2';
function init() {
initMap();
initUI();
}
var map, draw, modify, snap, point, line, poly;
function initMap() {
map = new OpenLayers.Map('map');
var styles = new OpenLayers.StyleMap({
"default": new OpenLayers.Style(null, {
rules: [
new OpenLayers.Rule({
symbolizer: {
"Point": {
pointRadius: 5,
graphicName: "square",
fillColor: "white",
fillOpacity: 0.25,
strokeWidth: 1,
strokeOpacity: 1,
strokeColor: "#3333aa"
},
"Line": {
strokeWidth: 3,
strokeOpacity: 1,
strokeColor: "#6666aa"
},
"Polygon": {
strokeWidth: 1,
strokeOpacity: 1,
fillColor: "#9999aa",
strokeColor: "#6666aa"
}
}
})
]
}),
"select": new OpenLayers.Style(null, {
rules: [
new OpenLayers.Rule({
symbolizer: {
"Point": {
pointRadius: 5,
graphicName: "square",
fillColor: "white",
fillOpacity: 0.25,
strokeWidth: 2,
strokeOpacity: 1,
strokeColor: "#0000ff"
},
"Line": {
strokeWidth: 3,
strokeOpacity: 1,
strokeColor: "#0000ff"
},
"Polygon": {
strokeWidth: 2,
strokeOpacity: 1,
fillColor: "#0000ff",
strokeColor: "#0000ff"
}
}
})
]
}),
"temporary": new OpenLayers.Style(null, {
rules: [
new OpenLayers.Rule({
symbolizer: {
"Point": {
graphicName: "square",
pointRadius: 5,
fillColor: "white",
fillOpacity: 0.25,
strokeWidth: 2,
strokeColor: "#0000ff"
},
"Line": {
strokeWidth: 3,
strokeOpacity: 1,
strokeColor: "#0000ff"
},
"Polygon": {
strokeWidth: 2,
strokeOpacity: 1,
strokeColor: "#0000ff",
fillColor: "#0000ff"
}
}
})
]
})
});
// create three vector layers
poly = new OpenLayers.Layer.Vector("polygons", {
strategies: [new OpenLayers.Strategy.Fixed()],
protocol: new OpenLayers.Protocol.HTTP({
url: "data/poly.json",
format: new OpenLayers.Format.GeoJSON()
}),
styleMap: styles,
isBaseLayer: true
});
line = new OpenLayers.Layer.Vector("lines", {
strategies: [new OpenLayers.Strategy.Fixed()],
protocol: new OpenLayers.Protocol.HTTP({
url: "data/line.json",
format: new OpenLayers.Format.GeoJSON()
}),
styleMap: styles
});
point = new OpenLayers.Layer.Vector("points", {
strategies: [new OpenLayers.Strategy.Fixed()],
protocol: new OpenLayers.Protocol.HTTP({
url: "data/point.json",
format: new OpenLayers.Format.GeoJSON()
}),
styleMap: styles
});
map.addLayers([poly, line, point]);
// configure the snapping agent
snap = new OpenLayers.Control.Snapping({
layer: poly,
targets: [point, line, poly],
greedy: false
});
snap.activate();
// add some editing tools to a panel
var panel = new OpenLayers.Control.Panel({
displayClass: "olControlEditingToolbar"
});
draw = new OpenLayers.Control.DrawFeature(
poly, OpenLayers.Handler.Polygon,
{displayClass: "olControlDrawFeaturePoint", title: "Draw Features", handlerOptions: {holeModifier: "altKey"}}
);
modify = new OpenLayers.Control.ModifyFeature(
poly, {displayClass: "olControlModifyFeature", title: "Modify Features"}
);
panel.addControls([
new OpenLayers.Control.Navigation({title: "Navigate"}),
draw, modify
]);
map.addControl(panel);
// give the map a location
map.setCenter(new OpenLayers.LonLat(0, 0), 1);
}
/**
* Add behavior to page elements. This basically lets us set snapping
* target properties with the checkboxes and text inputs. The checkboxes
* toggle the target node, vertex, or edge (boolean) values. The
* text inputs set the nodeTolerance, vertexTolerance, or edgeTolerance
* property values.
*/
function initUI() {
var check = document.getElementById("snapping");
check.checked = true;
check.onclick = function() {
if(check.checked) {
snap.activate();
} else {
snap.deactivate();
}
};
var sel = document.getElementById("editable");
sel.value = "poly";
sel.onchange = function() {
updateEditable(sel.value);
};
var target, type, tog, tol;
var types = ["node", "vertex", "edge"];
for(var i=0; i<snap.targets.length; ++i) {
target = snap.targets[i];
for(var j=0; j<types.length; ++j) {
type = types[j];
tog = document.getElementById(i + "_" + type);
tog.checked = target[type];
tog.onclick = (function(tog, type, target) {
return function() {target[type] = tog.checked;}
})(tog, type, target);
tol = document.getElementById(i + "_" + type + "Tolerance");
tol.value = target[type + "Tolerance"];
tol.onchange = (function(tol, type, target) {
return function() {
target[type + "Tolerance"] = Number(tol.value) || 0;
}
})(tol, type, target);
}
}
}
// this function allows the editable layer to be changed
// for the snapping control, this amounts to calling setLayer
function updateEditable(name) {
layer = window[name];
// update the editable layer for the snapping control (nice)
snap.setLayer(layer);
// update the editable layer for the modify control (ugly)
var modActive = modify.active;
if(modActive) {
modify.deactivate();
}
modify.layer = layer;
modify.selectControl.layer = layer;
modify.selectControl.handlers.feature.layer = layer;
modify.dragControl.layer = layer;
modify.dragControl.handlers.drag.layer = layer;
modify.dragControl.handlers.feature.layer = layer;
if(modActive) {
modify.activate();
}
// update the editable layer for the draw control (very ugly)
var drawActive = draw.active;
if(drawActive) {
draw.deactivate();
}
draw.layer = layer;
var handler = ({
point: OpenLayers.Handler.Point,
line: OpenLayers.Handler.Path,
poly: OpenLayers.Handler.Polygon
})[name];
draw.handler = new handler(draw, draw.callbacks, draw.handlerOptions);
if(drawActive) {
draw.activate();
}
}
</script>
</head>
<body onload="init()">
<h1 id="title">Snapping Example</h1>
<div id="tags">
vector, feature, snapping, stylemap, advanced
</div>
<div id="shortdesc">A demonstration snapping while editing vector features.</div>
<div id="map" class="smallmap"></div>
<br>
<label for="editable">Editable Layer:</label>
<select id="editable" name="editable">
<option value="poly">polygons</option>
<option value="line">lines</option>
<option value="point">points</option>
</select>
<label for="snapping">Enable Snapping</label>
<input type="checkbox" name="snapping" id="snapping" checked="checked" />
<table>
<tbody>
<tr class="head">
<td>targets</td><td>node</td><td>vertex</td><td>edge</td>
</tr>
<tr>
<td>points</td>
<td><input type="checkbox" id="0_node" /><input id="0_nodeTolerance" type="text" size="3" /></td>
<td><input type="checkbox" id="0_vertex" /><input id="0_vertexTolerance" type="text" size="3" /></td>
<td><input type="checkbox" id="0_edge" /><input id="0_edgeTolerance" type="text" size="3" /></td>
</tr>
<tr>
<td>lines</td>
<td><input type="checkbox" id="1_node" /><input id="1_nodeTolerance" type="text" size="3" /></td>
<td><input type="checkbox" id="1_vertex" /><input id="1_vertexTolerance" type="text" size="3" /></td>
<td><input type="checkbox" id="1_edge" /><input id="1_edgeTolerance" type="text" size="3" /></td>
</tr>
<tr>
<td>polygons</td>
<td><input type="checkbox" id="2_node" /><input id="2_nodeTolerance" type="text" size="3" /></td>
<td><input type="checkbox" id="2_vertex" /><input id="2_vertexTolerance" type="text" size="3" /></td>
<td><input type="checkbox" id="2_edge" /><input id="2_edgeTolerance" type="text" size="3" /></td>
</tr>
</tbody>
</table>
<p>Though all snapping types are shown here for all target layers, not all are sensible.
Points don't have edges, for example.</p>
</body>
</html>
|
