ST_Transform throwing error
abenrob opened this issue · 11 comments
Hello !
I'm trying to expand my proposed series on spl.js, and I came across an issue -
When trying to use ST_Transform(), I get Error: ST_Transform exception - PROJ reports "proj_create: no database context specified".
The test SQL: SELECT ST_Buffer(ST_Transform(MakePoint(5.7245, 45.1885,4326),3857), 200);
Is this from the lib, or my src DB, or the sqlite version at Observable, or something else?
Hi Adam,
in order to perform transformations you will need to load proj.db. Please take a look at the source here: https://github.com/jvail/spl.js/blob/main/examples/openlayers.html
The problem with proj.db is that it is so big. I hope I can include a minimal proj.db into the build later. For now you need to either download the entire db and add it as an arraybuffer or you try the remote approach as in the example (disadvantage: many, many get requests are fired).
Thanks. Trying it out now. Are there resources for building this? If my examples only need 3857 & 4326, I wonder if I could compile a version only containing those...
Awesome Jan! Thanks!
Thanks. Trying it out now. Are there resources for building this? If my examples only need 3857 & 4326, I wonder if I could compile a version only containing those...
I'll keep the ticket closed, but any info on where proj.db comes from,and how to build it will be appreciated!
Nice notebook example! I'll add a link to the readme once it is done.
Are there resources for building this? If my examples only need 3857 & 4326, I wonder if I could compile a version only containing those...
The problem (and the solution - I hope) with proj.db on the web is here: OSGeo/PROJ#3022
Nice notebook example! I'll add a link to the readme once it is done.
Thanks for the PR & a very nice notebook! Just one thing I noticed (not important): mapbox seems to have an issue updating the canvas. When I move the slider some parts of the previous buffer are still visible.
Hm - what browser/os ? I don't see that effect on mine, but I only test what I use habitually...
I am using the latest FF.
I'm on FF 101.0.1 (64-bit) on OSX 11.6 (20G165) I see a very slight effect like that, moreso on buffer dist change than on marker move. Maybe a very slight debounce could help... I'll keep it in mind!
Just tested in chrome and it is completely smooth - seems it is a FF thing.