Update app.py

app.py

@@ -1,48 +1,54 @@
-import os
-
-import mapwidget.cesium as mapwidget
+import numpy as np
+import holoviews as hv
+import dask.dataframe as dd
 
+from holoviews import opts
+from holoviews.operation.datashader import aggregate
 import panel as pn
+from utils import get_meta_data
+
+pn.extension()
+
+hv.extension('bokeh')
 
-pn.extension("ipywidgets")
+renderer = hv.renderer('bokeh')
 
-try:
-    token = os.environ["CESIUM_TOKEN"]
-except KeyError as ex:
-    raise EnvironmentError(
-        "CESIUM_TOKEN environment variable not set. "
-        "Sign up for free and get a free Cesium token here https://ion.cesium.com/signup/"
-    ) from ex
+opts.defaults(
+    opts.Curve(xaxis=None, yaxis=None, show_grid=False, show_frame=False,
+               color='orangered', framewise=True, width=100),
+    opts.Image(width=800, height=400, shared_axes=False, logz=True, colorbar=True,
+               xaxis=None, yaxis=None, axiswise=True, bgcolor='black'),
+    opts.HLine(color='white', line_width=1),
+    opts.Layout(shared_axes=False),
+    opts.VLine(color='white', line_width=1))
 
-cesium_map = mapwidget.Map(
-    center=[40.70605, -74.01177], height="650px", altitude=600, token=token
-)
+pandas_df = pn.cache(get_meta_data)()
+df = dd.from_pandas(pandas_df).persist()
 
-component = pn.panel(cesium_map, sizing_mode="stretch_width")
+points = hv.Points(df, kdims=['centre_easting', 'centre_northing'], vdims=[])
 
-description = """# MapWidget
+agg = aggregate(points, link_inputs=True, x_sampling=0.0001, y_sampling=0.0001)
 
-Custom Jupyter widgets for creating interactive 2D/3D maps using popular JavaScript libraries with bidirectional communication, such as `Cesium`, `Mapbox`, `MapLibre`, `Leaflet`, and `OpenLayers`.
+agg.opts(cmap="kr_r")
 
-By **Qiusheng Wu**
+pointerx = hv.streams.PointerX(x=np.mean(points.range('centre_easting')), source=points)
+pointery = hv.streams.PointerY(y=np.mean(points.range('centre_northing')), source=points)
+box = hv.streams.BoundsXY(source=points, bounds=(0,0,0,0))
+vline = hv.DynamicMap(lambda x: hv.VLine(x), streams=[pointerx])
+hline = hv.DynamicMap(lambda y: hv.HLine(y), streams=[pointery])
 
-<img src="https://avatars.githubusercontent.com/u/5016453?v=4" style="width:100%;"> 
+tiles = hv.Tiles('https://tile.openstreetmap.org/{Z}/{X}/{Y}.png', name="OSM").opts(width=600, height=550)
+hvobj = tiles * agg * hline * vline
 
-# Cesium
+@pn.depends(pointerx.param.x, pointery.param.y)
+def table(x,y):
+    return f"Easting: {x}, Northing: {y}"
 
-Cesium is the open platform for software applications designed to unleash the power of 3D data.
+@pn.depends(box.param.bounds)
+def bbox(value):
+    return str(value)
 
-<img src="https://images.prismic.io/cesium/a4dc3936-e083-4337-ba48-bb5bba78b2a1_ion_color_white.png" style="width:100%;"> 
-"""
+pn.pane.HoloViews(hvobj).servable()
 
-pn.template.FastListTemplate(
-    site="Awesome Panel",
-    site_url="https://awesome-panel.org",
-    logo="https://panel.holoviz.org/_static/logo_horizontal_dark_theme.png",
-    title="mapwidget.cesium",
-    theme="dark",
-    theme_toggle=False,
-    main_layout=None,
-    main=[component],
-    sidebar=[description],
-).servable()
+pn.panel(table).servable()
+pn.panel(bbox).servable()