Add README.md for config

Author: blackchou32

ships_hybrid_algorithm/config/README.md

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+# CONFIG
+
+Config file for Ship Movement Model
+
+## Parameters
+
+* simulation_steps -> Number of steps (seconds) of the simulation
+* max_speed_range -> Max speed of the ship in this range (random)
+* speed_variation -> if enabled, the maximum delta between targeted speed and real speed
+* directional_variation -> if enabled, ship heading can be deviated
+* resolution -> increase for less compute time, but ships can be stuck
+* obstacle_threshold -> how close a ship can approach an obstacle
+
+* ports [x,y] -> coordinates of the port, in grid coordinates
+* speed_limit_zone[x,y] -> coordinates and max speed of a speed limit zone, in grid coordinates
+* obstacle [[x1,y1],...,[xn,yn]] -> coordinates of an obstacle, in grid coordinates
+
+* geospatial_bounds -> min and max lat/lon of the map, in decimal degrees
+
+
+## How to have accurate obstacle coordinates
+
+1. Install and open qgis (https://qgis.org/)
+2. Create project. Specify EPSG 4326 (WGS 84)
+3. Install QuickOSM plugin
+4. Using QuickOSM quick request, request KEY=boundaries and VALUE=administrative. You can filter to have only relevant boundaries
+5. Now you will have polygons' coordinates with your obstacle. Convert them in grid coordinates and use them in configV2.json
+
+## My map is distorded
+
+You need x,y to have the same ratio aspect as the lon,lat of your map. For exemple :
+
+1. Get min/max lon/lat of your area (in degrees)
+2. Decide height of the map in grid coordinates (eg, 500)
+3. Get the "mean latitude" of your map (eg, $\phi_0$).
+4. Ratio is :
+$$
+R \approx \cos(\phi_0)\cdot \frac{\Delta lon}{\Delta lat}
+$$
+5. Now you have : $x = y \times R$