using gdal/ogr with epd

I had to add the gdal and ogr libraries to a fresh EPD 4.3.0 Windows install. Here is how i’ve done and what were the problems encountered :

1. Install the python module : easy_install gdal
2. Add the dll libraries : Download and uncompress to c:\gdalwin32-1.6 from http://download.osgeo.org/gdal/win32/1.6/
3. Update your path

This is were you had to manually do some updates. I haven’t exactly found the culprit but there is a problem with the OpenSSL dynamic libraries (libeay32.dll and ssleay32.dll). There is one version in c:\Windows\System32, one in c:\Python25 and one in c:\gdalwin32-1.6\bin directory.

If you do not update the path, you get the following error when loading ogr :

The ordinal 3873 could not be located in the dynamic library LIBEAY32.DLL

and the library cannot be loaded.

Just put your c:\gdalwin32-1.6\bin\ directory on the first place in your path :

PATH=c:\gdalwin32-1.6\bin\;%PATH%

Hope this will help.

Debugging OpenLayers scripts

While developping application using the great OpenLayers library, I often face the problem of javascript debugging. I found very nice applications to help me do it :

using OpenLayers filters with Cluster strategy

OpenLayers filters allows you to apply complex styling to your layers. I wondered how I could use the Cluster strategy with a specific styling that should apply when the clusters contains only one point.

Converting MrSid files

Using the sidgeodecode tool provided freely by Lizardtech, I was able to convert .sid files to .tiff or .jpeg file.

The -wf option did not work as expected. It created a .tfw file without keeping the original georeference from the .sid file.

The easy workaround was to simply rename/copy the .sdw file to a .tfw or .jgw file to keep the georerences !