From a7b8751bbc4a4d3e4c8019f5b8a2d6066f8415c2 Mon Sep 17 00:00:00 2001
From: Jeff Moe <moe@spacecruft.org>
Date: Wed, 11 May 2022 16:25:39 -0600
Subject: [PATCH] Minimally working Galileo map based on satellite-czml example

---
 gnss-earth.py | 149 ++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 149 insertions(+)
 create mode 100755 gnss-earth.py

diff --git a/gnss-earth.py b/gnss-earth.py
new file mode 100755
index 0000000..33fc119
--- /dev/null
+++ b/gnss-earth.py
@@ -0,0 +1,149 @@
+#!/usr/bin/python3
+
+import random
+import urllib.request
+import dash
+import dash_html_components as html
+import dash_core_components as dcc
+from dash.dependencies import Input, Output
+from datetime import datetime, timedelta
+from satellite_czml import satellite_czml
+from satellite_czml import satellite
+
+url = 'https://celestrak.com/NORAD/elements/galileo.txt'
+apikey = open('cesium.key').read().strip()
+tles = [l.decode("utf-8").strip() for l in urllib.request.urlopen(url).readlines()]
+tle_list = [[tles[i],tles[i+1],tles[i+2]] for i,_ in enumerate(tles) if i%3==0]
+small_tle_list = tle_list
+
+single_tle = [tle_list[0]]
+single_tle
+
+single_czml = satellite_czml(tle_list=single_tle).get_czml()
+
+multiple_czml = satellite_czml(tle_list=small_tle_list).get_czml()
+
+name_list = [t[0] for t in small_tle_list]
+description_list = ['Station: ' + t[0] for t in small_tle_list]
+color_list = [[random.randrange(256) for x in range(3)] for x in range(len(small_tle_list))]
+size_list = [7] * len(small_tle_list)
+
+czml_obj = satellite_czml(tle_list=small_tle_list, name_list=name_list, description_list=description_list,
+                          color_list=color_list, speed_multiplier=1, use_default_image=False,
+                          marker_scale_list=size_list, show_label=False, show_path=False,
+                          ignore_bad_tles=True)
+multiple_czml_p = czml_obj.get_czml()
+
+multiple_sats=[]
+for tle in small_tle_list:
+    sat = satellite(tle,
+                    description='Station: ' + tle[0],
+                    color = [random.randrange(256) for x in range(3)],
+                    marker_scale=12,
+                    use_default_image=False,
+                    start_time=datetime.strptime('2020-01-01 00:00:00','%Y-%m-%d %H:%M:%S'),
+                    end_time=datetime.strptime('2020-01-01 01:00:00','%Y-%m-%d %H:%M:%S'),
+                    show_label=True,
+                    show_path=True,
+                   )
+    multiple_sats.append(sat)
+
+czml_obj = satellite_czml(satellite_list=multiple_sats)
+multiple_czml_c = czml_obj.get_czml()
+
+last_sat_key = list(czml_obj.satellites.keys())[-1]
+last_sat = czml_obj.satellites[last_sat_key]
+
+# Change the path to display the orbit path
+last_sat.build_path(rebuild=True,
+                    show=True,
+                    color=[255, 255, 0, 127],
+                    width=3
+                   )
+
+# Change the label look
+last_sat.build_label(rebuild=True,
+                     show=True,
+                     font='12pt Arial',
+                     color=[255, 255, 0, 200],
+                     outlineColor=[0, 0, 0, 127],
+                     outlineWidth=3,
+                    )
+
+# Change the marker (billboard)
+last_sat.build_marker(rebuild=True,
+                      size=18,
+                      outlineColor=[0, 0, 0, 128],
+                     )
+
+modified_czml = czml_obj.get_czml()
+
+
+external_css = ['https://cesium.com/downloads/cesiumjs/releases/1.76/Build/Cesium/Widgets/widgets.css']
+
+external_scripts = [{'src':'https://cesium.com/downloads/cesiumjs/releases/1.76/Build/Cesium/Cesium.js'}]
+
+app = dash.Dash(__name__,
+                title='satellite_czml',
+                external_scripts=external_scripts,
+                external_stylesheets=external_css)
+
+app.layout = html.Div(children=[
+    dcc.Dropdown(id='choose_czml_dd',
+                 options=[
+                     {'label': 'Single CZML', 'value': 'single_czml'},
+                     {'label': 'Multiple CZML', 'value': 'multiple_czml'},
+                     {'label': 'Specified Arguments CZML', 'value': 'multiple_czml_p'},
+                     {'label': 'Create One-by-One CZML', 'value': 'multiple_czml_c'},
+                     {'label': 'Modified CZML', 'value': 'modified_czml'}
+                 ],
+                 value='single_czml'
+                ),
+    html.Div(id='cesiumContainer'),
+    html.Div(id='czml', style={'display': 'none'}),
+    html.Div(id='apikey', style={'display': 'none'}, children=apikey)
+])
+
+@app.callback(
+    Output('czml', 'children'),
+    Input('choose_czml_dd', 'value'))
+def update_satellite_filter(v):
+    d = {'single_czml':single_czml,
+         'multiple_czml':multiple_czml,
+         'multiple_czml_p':multiple_czml_p,
+         'multiple_czml_c':multiple_czml_c,
+         'modified_czml':modified_czml
+        }
+    return d[v]
+
+app.clientside_callback('''
+function(id, czml, apikey) {
+    // Create the Cesium Viewer
+    if (!window.viewer) {
+        Cesium.Ion.defaultAccessToken = apikey;
+        window.viewer = new Cesium.Viewer(id,{
+            shouldAnimate: true,
+        });
+        window.viewer.scene.globe.enableLighting = true;
+    }
+
+    // Update the Cesium Viewer
+    if (czml) {
+        window.viewer.dataSources.removeAll();
+        czmlJson = JSON.parse(czml);
+        window.viewer.dataSources.add(
+            Cesium.CzmlDataSource.load(czmlJson)
+        );
+    }
+
+    return true;
+}''',
+    Output('cesiumContainer', 'data-done'),
+    Input('cesiumContainer', 'id'),
+    Input('czml', 'children'),
+    Input('apikey', 'children')
+)
+
+if __name__ == '__main__':
+    app.run_server(debug=True, use_reloader=False)
+