php - Detect water/sea between two lat longs
How can we detect is there any water/sea between two lat-longs using google map API or any PHP library.
e.g. In the attached image, there is water between Marker H and Marker P so somehow I want to know that yes there is water between this two lat-longs.
Note: It is different from Verify if a point is Land or Water in Google Maps
In my question I want to detect is there any water between two lat-longs, I don't want to know that my lat-long is on land or on water.