##Graphical (Google) KML file editor version 0.2 - editing Google map path coordinates (without map background)
Read (Google maps) KML file: The read_kml_file() function reads the selected KML file and extracts the KML geo-data from it.
It removes the first XML declaration if exists before further processing by fastkml module.
Extracting coordinates: The function extract_coordinates() extracts the coordinates from the KML file.
Calculation of the bounding box: The calculate_bounding_box() function calculates the smallest (geo-coordinate based) bounding box for the given coordinates.
Displaying coordinates: The software displays the coordinates on a 2D canvas (software window), where individual points can be moved interactively.
If any change occurs in the coordinates, the modified path can be saved as a basic (Google map compatible) kml file. Supplementary informations may be lost, modified path is suggested to be saved as a copy!
This code allows you to graphically display the coordinates of Google Maps KMZ files and move points interactively. If you need additional functions, the code can be further developed.
##Functionality Test&Samples:
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src folder contains the Python3 code to run
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test subfolder contains:
a) history-2024-08_original.kml, a Google KML file containing 2 paths (one driving and one walking), that can be loaded and modified. Original and modified path lines are demonstrated as images, see the info folder section.
b) history-2024-08_modified.kml a modified version of the above mentioned file, in a simple Google Maps compatible format
Both kml files can be imported in the Google Own Map services, when a new map is created and a new layer is added to the map, then the Import option show up and can be used for data import.
- info folder contains:
a) before_modification.png and original_path_Gmap.png, which show the software window with the registered path points and the same path on the map, respectively,
b) modified_points.png highlighted in yellow those locations which have been modified (by Drag&Drop) and modification_groups.png showing the points that are moved from their original location,
c) after_modification.png and modified_path_Gmap.png, which show the software window with the original path points besides the modified points and the same modified path on the (Google My Maps) map, respectively.
##Notes: Google map path contains multiple points as parts of a Linestring which defines a set of geo-coordinates which should be connected (on the map by a line) in the order of appearence. Google PolyLines, examples
Google map is not loaded to serve as background as it requires Google API key. Not part of this basic software!
##Prerequisites: in command line prompt, install the following modules by typing: pip install fastkml tkinter shapely
Check existance of pygeoif module in Python IDLE (or IDE) by an import test: from pygeoif import Point, LineString
Modified path saved to Google Maps compatible KML format:
<?xml version="1.0" encoding="UTF-8"?>
<kml xmlns="http://www.opengis.net/kml/2.2">
<Document>
<Placemark>
<LineString>
<coordinates>17.2012735,47.8064775,0 </coordinates>
</LineString>
</Placemark>
</Document>
</kml>-
removing points would be a key point and easy-to-make option,
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in contrast adding track points is a bit more tricky because the points should be added at the right place in the order of points (LineString) to avoid dizzy lines,
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highlighting a point by clicking is an easy request but I consider it does not add much to the track modification functionality, rather it serves fanciness only,
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adding real maps (with continuous updates) in the background would be the best development as a positive outcome but has a high coding time demand, but either the software should use a common Google API key that due to economical reasons Google does not offer, or each user should use their own API key which I consider to be an overcomplication of the task and functionality.
@author: Data4every1 Created on Mon Aug 10 14:12:27 2024