He explained that he got the image from NOAA and that you cd create the needed tiles w/ gdal using the gdal2tiles.py script.
Sounds easy, huh?
But I cdn’t find the gdal2tiles.py script. Loooong story short, I macports installed 1.6.3 which I’m not sure includes gdal2tiles.py.
So then I installed KyngChaos‘s GDAL 1.7 which did have the script.
Then I downloaded a chart from NOAA – I picked Idaho b/c it was small (4 MB). I unzipped that file which produced several directories of files. I don’t know raster so I wasn’t sure what these files were??? And when I tried using gdal2tiles.py w/ them, I didn’t know what to do. 🙂
Fortunately, MapTiler provides a GUI for gdal2tiles.py and allowed me to select the files (1 at a time). I just processed one using the Spatial Reference System ‘Custom definition of the system (WKT, Proj.4,..)’… whatever that means.
I processed that and it produces a bunch more directories w/ pngs – now there’s something I understand. I used the 10-15 zoom levels for processing so it produced a dir for each of those w/ subdirs and images.
I removed the project’s images under ‘Tiles’ and copied my new images there, added them to the project and… nothing. For some reason, the images weren’t being found in the dir structure expected by the project???
I noticed the images in the original project weren’t in the project target’s ‘copy bundle resources.’ How were the images getting included in the build?
I tried several things, but what worked was to NOT remove the original images, add my new image dirs and THEN remove the original image groups/folders/dirs from the project.
I’d love to know what’s going on there???
The good thing is, once it worked, it worked… sorta. It overlayed the image and even recentered the map but I don’t think it’s in the right location b/c the river shown in the image doesn’t seem to be there on the map.
So I’m still working on that, but wanted to get the above down before I forgot what I did.
I’d love to hear any comments on places that cd be done better above or make the location work right, etc.