Artem Pavlenko wrote: > > On 4 Feb 2008, at 02:01, John Zastrow wrote: > >> I need to create an attractive set of static tiles for the USA (based on >> shapefiles) to populate a web-server-only (e.g., small-footprint, not >> dynamic, not a real map server) online map to embed in a java-based >> application without internet access. >> >> My first attempt used ArcGIS to render a GeoTIFF of a layout at high >> resolution and then passed the image into gdal2tiles.py >> (http://www.klokan.cz/projects/gdal2tiles/) (which is EXCELLENT) to >> create a shell OpenLayers app that I can customize. This worked fine, >> except the image quality from ArcGIS was horrible, particularly when >> zoomed in (no anti-alias). > > I don't think your approach will work. Even if you manage to create a > very large geotiff, re-sampling it to create low resolution tiles > would produced anything but nice looking maps. Also, for high zoom > levels the image size will blow your memory away. Creating good > cartography would most certainly require per zoom level styling. > >> >> I'm a now trying to use mapnik (mapnik.org) to create the same image at >> higher quality. But I am suffering deeply from an acute lack of >> documentation which makes creating the cartography even more painful >> (where are recipes, examples, and docs for mapnik?) > > Have a look at : > http://trac.openstreetmap.org/browser/applications/rendering/mapnik/generate_tiles.py > > [1] > This script generates tiles with all styles and data defined in : > http://trac.openstreetmap.org/browser/applications/rendering/mapnik/osm.xml > > >> >> Is there something else that I can use to create the tiles needed for >> the OpenLayers app? > > I suggest you read OpenLayers docs. > >> Or is there an easier tool for creating a high-res, >> high-quality georeferenced image that can be used by gdal2tiles.py? Any >> thoughts would be greatly appreciated. > > I'm not familiar with gdal2tiles.py but as I mentioned above, > re-sampling vector maps won't produce high-res, high-quality tiles > (assuming this is what you're trying to achieve). You might try > creating two layers : chop your raster data with gdal2tiles.py and > create transparent overlay tiles using Mapnik. Also, Mapnik supports > gdal raster directly and you can generate high quality tiles with > raster and vector combined. see [1] > > HTH > Artem Ok, you lost me a little with your last note (I agree, I'd like to weave together at least two zoom levels into a static tile set). Are you saying that Mapnik can import the newly cut tiles and set transparency (perhaps based on a color)? Can you elaborate on what I would do with Mapnik's support for GDAL rasters? If [1] was a link it did not come through in the email.
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