# GPS Triangulation

You have already built a map and you want to triangulate it with google maps.You can now easily do so using this feature.

• You can login to the Developer Portal and download the Sparse.ply file from the map you want to triangulate.

• Click on map-name-sparse.ply to download the map

1. Open blender.

2. Import the .ply point cloud file to blender.

   

3. Rotate it 90 degrees in x in blender.

   

   

4. Find at least 3 points that you can recognize from google maps.

   

5. Add the points to map_ecef_from_3_wgs84_points.py. (Please see the /blender-googlemaps-example-images) to do the conversion correctly.

def main() -> None:

    # 3 manually picked points in the map x, y, z
    map_position_a = np.array([0, 0, 0])
    map_position_b = np.array([0, 0,  0])
    map_position_c = np.array([0, 0,  0 ])

6. Find the same points in google maps. Add them to the map_ecef_from_3_wgs84_points.py script.

 # latitude, longitude, and altitude values for the 3 points (From Google maps)
    wgs84_a = np.array([0.0, 0.0, 0.0])
    wgs84_b = np.array([0.0, 0.0, 0.0])
    wgs84_c = np.array([0.0, 0.0, 0.0])

7. Run the script. You need to add your token and mapid. It will also ask to pip install bunch of libraries. Install them.

8. After the script runs successfully it will print out the result and update the map metadata in developer portal. To verify this. Check the metadata.json for the map from the portal.

1. Download test images that you know have been captured in within the same area. Use the support portal to download the job.

2. Run localize-map-images_lat_lon.py. You need to add the folder where the images are and your token and map id. The script will create a localization_results.json and will write each loc there. You can also stop the script if you don't want to localize all images in the images folder.

3. Run the show-locs-on-folium.py. You need to also add to the script the localization_results.json path. The script will run and open up the browser it will also create a localization_map.html file. You will see a map with the successful localization results. If you click a point on the map it will open up showing the lat, lon and image path.

4. Copy paste the image path open terminal and type $open and paste the image path. example: $open /path/to/image

That way you can check if the images match to the map.

Create a virtual env. Type these commands to terminal.

$ python -m venv env

$ source env/bin/activate

if you don't have folium install with this command

$ pip install folium   

then you run the python script

To deactivate the virtual env use

$ deactivate

Here is the video tutorial for all the steps.