README

contours/README.md

@@ -1,27 +1,39 @@
 Countour line generator from LIDAR data
 ---------------------------------------
 
+This accepts two kinds of contour data:
+
+*2009 variant*: x, y, z, separated by one or more spaces:
+```
+ 501991.670  6150000.000  57.689
+```
+
+*Non-gridded*, therefore significantly slower (`gdal_grid` must be used before making contours, which is slow).
+
+
+*2017*: y, x, z, separated by commas:
+```
+6062999.75,584000.75,88.07
+```
+
+This is *gridded*, so quite fast.
+
 Usage:
 
-1. Download contour lines in format `6062999.75,584000.75,88.07`: coordinate
-   pair and height (in meters) to `DTM_XX_YY_N.zip` files.
-2. Adjust `BOUNDS` in the Makefile.
+1. Download contour lines to zip files in this directory.
+2. Adjust `BOUNDS` and `VARIANT` in `config.mk`.
 3. Run `make -j$(nproc) smooth_<X>.gpkg`. This will output a geo-package with
    contour lines every `X` meters. X can be fractional (e.g.
    `smooth_2.5.gpkg`).
 4. Optional: you may generate a raster image with `layer2img.py`.
 
-Dependencies:
+Dependencies for a Linux system:
 
-- postgis
+- docker
+- psql (client only)
 - gdal-bin
 - unzip
-
-TODO:
-
-1. Replace `managedb` stack with postgis-over-docker. This will lead to a less
-   fragile postgis setup.
-2. Accept `BOUNDS` in a way that does not require to change the Makefile.
+- awk
 
 Example
 -------