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updated the description and documentation of the example. p=marcjansen, r=me (closes #2869)

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git-svn-id: http://svn.openlayers.org/trunk/openlayers@10973 dc9f47b5-9b13-0410-9fdd-eb0c1a62fdaf
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ahocevar
2010-12-17 10:02:05 +00:00
parent 697ee375b8
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examples/simplify-linestring.html
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@@ -1,7 +1,8 @@
<!DOCTYPE html>
<html>
<head>
<title>Simplify LineString</title>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>Simplify a LineString geometry</title>
<link rel="stylesheet" href="../theme/default/style.css" type="text/css">
<link rel="stylesheet" href="style.css" type="text/css">
<style type="text/css">
@@ -15,19 +16,23 @@
width: 300px;
float: left;
}
#docs {
clear: both;
}
</style>
</head>
<body>
<h1 id="title">Simplify a LineString</h1>
<h1 id="title">Simplify a LineString geometry</h1>
<div id="tags">
Douglas-Peucker, Douglas, Peucker, Peuker, tolerance
</div>
<p id="shortdesc">
Shows the usage of the utility method "simplifyLineString" that
implements the Douglas-Peucker algorithm to remove "insignificant"
vertices from LineString geometries.
Shows the usage of the method &quot;simplify&quot; that implements
the Douglas-Peucker algorithm to remove &quot;insignificant&quot;
vertices from LineString geometries.
</p>
<div id="control-simplify">
<label for="tolerance">Tolerance factor:</label>
<input name="tolerance" id="tolerance" type="number" min="0" max="1" step="0.02" value="0.1">
<input type="button" id="simplify" value="Simplify LineString">
<input type="button" id="animation" value="Start animation">
@@ -38,20 +43,21 @@
</div>
<div id="info">
</div>
<div id="docs" style="clear: both;">
<div id="docs">
<p>
The method OpenLayers.Util.simplifyLineString can be used to
simplify linestring geometries. Simplification sometimes is
useful to enhance the perfomance of vector rendering or to
reduce complexity of geometries. This might be especially handy
when viewing geometries a small scales.
Instances of OpenLayers.Geometry.LineString have a method simplify,
that can be used to simplify linestring geometries.
Simplification sometimes is useful to enhance the perfomance of
vector rendering or to reduce complexity of geometries. This
might be especially handy when viewing geometries a small
scales.
</p>
<p>
OpenLayers.Util.simplifyLineString is a recursive implementation
of the famous Douglas-Peucker algorithm. It
is controlled by a tolerance factor that defines the threshold
for vertices to be considered "insignificant" for the general
structure of the geometry.
OpenLayers.Geometry.LineString::simplify is a recursive
implementation of the famous Douglas-Peucker algorithm. It is
controlled by a tolerance factor that defines the threshold for
vertices to be considered &quot;insignificant&quot; for the
general structure of the geometry.
</p>
<p>
The LineString on the left map can be simplified according to
@@ -59,12 +65,18 @@
Use a value between 0 and 1 for best results. If you navigate
the left map, the right map will show the same location to make
it easier to spot the differeces between the LineStrings.
</p>
</p>
<p>
The LineString
represents a part of the coastline of
<a href="http://www.openstreetmap.org/?lat=54.7309684753418&lon=83.1809234619141&zoom=11">this
place in Russia</a> &mdash; found via <a href="http://ryba4.com/python/ramer-douglas-peucker">an
You can also use the button &quot;Start animation&quot; to get
results for increasing tolerance-factors from 0.02 to 1.0. The
animation can be paused by clicking on the button &quot;Stop
animation&quot;.
</p>
<p>
The LineString represents a part of the coastline of
<a href="http://www.openstreetmap.org/?lat=54.7309684753418&amp;lon=83.1809234619141&amp;zoom=11">this
place southeast of Novosibirsk in Russia</a> &mdash; found via
<a href="http://ryba4.com/python/ramer-douglas-peucker">an
example implementation of the algorithm in python</a>.
</p>
<p>
@@ -77,10 +89,12 @@
(<a href="http://dx.doi.org/10.3138/FM57-6770-U75U-7727">DOI:
10.3138/FM57-6770-U75U-7727</a>).
</p>
<p>See <a href="simplify-linestring.js">simplify-linestring.js</a>
for the source code of this example.</p>
</div>
<script type="text/javascript" src="../lib/OpenLayers.js">
</script>
<script type="text/javascript" src="simplify-linestring.js">
<script type="text/javascript" src="./simplify-linestring.js">
</script>
</body>
</html>