tpg distance-to-best-photo map

0map.png

HOWTO.md

make a map of your TPG photo scores

in just a few easy far too many far too complex steps

compute the distances

1. Make a Postgres database with PostGIS
2. Add a photos table:

   CREATE TABLE photos(id SERIAL PRIMARY KEY, title VARCHAR(255), location geography(POINT, 4326) NOT NULL);
   CREATE INDEX photos_location ON photos USING GIST(location);

3. Load your photo locations into the photos table
4. Make a graticule table:

   create table graticule(geom geography(point,4326) not null);
   insert into graticule(select st_point(lng,lat)::geography from generate_series(-90,90,0.1) as lat, generate_series(-180,180,0.1) as lng);

5. Compute the best photo for every point on the graticule:

   create table raster as select graticule.geom, b.dist,b.id from graticule cross join lateral (select location <-> graticule.geom dist, id from photos order by dist limit 1) as b ;

6. Download the data to your local working directory:

   \copy (select st_x(geom::geometry),st_y(geom::geometry),dist from raster) to 'raster2.csv' csv;

plot the results

1. Rename raster2.csv to raster2.xyz
2. Convert to a TIFF, using gdal_translate from GDAL:

   gdal_translate -a_srs EPSG:4326 raster2.xyz raster2.tiff

3. Using QGIS or another tool of your choice, add the resulting TIFF as a raster layer to a new project.
4. Make it pretty, I guess