Steve<br><br>I don't have postgis, hence the fishing around for answers from helpful people like yourself! You are right about playing around with generalisations, unfortunately the colouring is very specific and needs to match other GIS outputs, so will have to still 'look' right - something I will have a play with in due course. Once you zoom in the data is quite usable - ie. the spatial index is doing it's job, so not all is lost.<br>
<br>Thanks for the ideas<br><br>Chris<br><br><div class="gmail_quote">On 2 September 2010 21:36, Lime, Steve D (DNR) <span dir="ltr"><<a href="mailto:Steve.Lime@state.mn.us">Steve.Lime@state.mn.us</a>></span> wrote:<br>
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<p class="MsoNormal"><span style="font-size: 11pt; color: rgb(31, 73, 125);">If you have postgis already sitting around then it’s
pretty quick just to try it and see. I’m assuming you’re
talking 20sec for everything, all 170K features? A spatial index doesn’t
buy you anything in the ‘all’ case. That is a lot of features to
display at once and I wonder if one can even make sense of that much detail. A
common technique would be display reduced or somehow generalized versions of
the data at that level and then hit the detailed data as a user zooms in.
Without knowing the data how you’d do that would vary. For example, you
could actually rasterize the data and display the pre-rendered raster version small
scales. Or you might be able to thin the data a bit. Lots of options.</span></p>
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<p class="MsoNormal"><span style="font-size: 11pt; color: rgb(31, 73, 125);">Steve</span></p><br></div></div></blockquote></div>