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Plotting Software
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30-07-2010 5:09pm#1
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You could do this with OpenLayers(like Google Maps API).I've used it here with maps from OpenStreetMap
Have a look at this example:POI example
Basically you make up text file delimited by tabs which contains the latitude,longitude,title and description for each marker.
There is a sample text file and details here:http://dev.openlayers.org/releases/OpenLayers-2.6/doc/apidocs/files/OpenLayers/Layer/Text-js.html.
You can pretty much copy and paste my code/POI Example and save as a .html file(webpage).
you just need to change the centre point of the map and the zoom level.
This is it with about 4,300 points.
This takes about 15s to load.I tried this with google maps and it crashed Firefox.
This is the HTML and JavaScript for the screenshot above.
[PHP]<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html>
<head>
<style type="text/css">
html { height: 100% }
body { height: 100%; margin: 0px; padding: 0px }
#map_canvas { height:100%;width:80%;float:left; }
</style>
<script src="http://www.openlayers.org/api/OpenLayers.js"></script>
<script type="text/javascript">
function init() {
map = new OpenLayers.Map("map_canvas");
map.addLayer(new OpenLayers.Layer.OSM());
//point to centre the map on
var lonLat = new OpenLayers.LonLat(-6.267845611572273,53.346652484299405)
.transform(
new OpenLayers.Projection("EPSG:4326"), // transform from WGS 1984
map.getProjectionObject() // to Spherical Mercator Projection
);
var zoom=12;
var pois = new OpenLayers.Layer.Text( "My Points",
{ location:"./points.txt",
projection: map.displayProjection
});
map.addLayer(pois);
map.setCenter(lonLat, zoom);
}
</script>
</head>
<body onload="init();">
<div id="map_canvas"></div>
</body>
</html>[/PHP]0 -
Wow! I was going to suggest amalgamating points at a particular zoom level.
It's trivial to convert lat/lon coords into KML (which is what google maps will read) but that gives you too many points. At a particular zoom level you could calculate the distance between points and if they were closer than x miles, amalgamate them together into one blob. I was going to try this in awk, which is probably not the language to do it in but what the hey...
But I think you just got everything you need! That's an impressive post duffman85. Gonna save that post for later
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I tried using this but out of about 4000 points, it only plotted one
Does the text file look like this:lat lon title description 10 20 title description 15 30 title2 description2
The first row is the column titles.
Is the text file in the same directory as the webpage?
Is it delimited by tab spaces?
Where is the one point?
I found if I did not have the .transform(...); part below that all my points mapped to the same point in the atlantic ocean just south of the Ghana and Ivory Coast which turns out to be N 0°00'00 , E 0°00'00
This code needs to be in one single line.var lonLat = new OpenLayers.LonLat(-6.267845611572273,53.346652484299405).transform(new OpenLayers.Projection("EPSG:4326"),map.getProjectionObject()); //transform from WGS 1984 to Spherical Mercator Projection0 -
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