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<div dir="ltr">Hi Steve,<br><br>looks promising.<br><br>If I got it right, the redraw time is influenced by <br>a) how many sub divisions are overlapping a given bbox and<br>b) how many objects are in these sub divisions and<br>c) how complex the objects are (means, how much time it takes to render them)<br><br>The optimization goal for a given bbox would be to minimize the number<br>of (complex) objects which are outside of the bbox, as<br>they have to be rendered and then ignored.<br>So, maybe we can calculate a ratio between "number of objects to render" and <br>"number of objects in the bbox" and try to optimize (minimize) that.<br><br>As we don't have a given bbox, we may create a grid<br>and measure and report the ratio of each grid element.<br><br>In the past it turned out to be rather difficult to split roads<br>at this stage, so I'd like to leave them out and split<br>only shapes and normal lines.<br>A possible alternative to splitting roads could be to place<br>large road objects into their own sub division, so that<br>they don't contain other objects. <br><br>I think I'll create a new branch for that stuff.<br><br>Gerd<br><br><div>Date: Mon, 10 Nov 2014 08:46:10 +0000<br>From: steve@parabola.me.uk<br>To: mkgmap-dev@lists.mkgmap.org.uk<br>Subject: Re: [mkgmap-dev] Optimizing MapSplitter<br><br><pre>Hi Gerd<br> <br>> So, what I am looking for is a tool that helps to find<br>> areas which are heavily overlapped, something like<br>> a heatmap.<br> <br>When displayed it looks like this:<br><a href="http://files.mkgmap.org.uk/download/223/Selection_040.png" target="_blank">http://files.mkgmap.org.uk/download/223/Selection_040.png</a><br> <br>I need to add a couple of getters and a fix to mkgmap (attached)<br>then I will check it all into display.<br> <br>..Steve<br> <br> <br></pre><br>_______________________________________________
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