Add DEM and Slope Maps

app.py

@@ -218,6 +218,44 @@ def get_wayback_data():
         print(f"An unexpected error occurred in get_wayback_data: {e}")
         return pd.DataFrame() # Return empty dataframe on failure
 
+def get_dem_slope_maps(ee_geometry):
+    """Creates DEM and Slope maps from SRTM data."""
+    one_time_setup() # Ensure GEE is initialized
+    
+    # --- DEM Map ---
+    dem_map = gee_folium.Map(add_google_map=True) # Add basemap for context
+    dem_map.centerObject(ee_geometry)
+
+    dem_image = ee.Image("USGS/SRTMGL1_003").clip(ee_geometry)
+
+    stats = dem_image.reduceRegion(reducer=ee.Reducer.minMax(), geometry=ee_geometry, scale=30, maxPixels=1e9).getInfo()
+    
+    # Check if data is available
+    if not stats or stats.get('elevation_max') is None:
+        dem_map_html = "<div>No DEM data available for this area.</div>"
+        slope_map_html = "<div>No Slope data available for this area.</div>"
+        return dem_map_html, slope_map_html
+
+    min_elev, max_elev = stats['elevation_min'], stats['elevation_max']
+    vis_params = {"min": min_elev, "max": max_elev, "palette": ["blue", "green", "yellow", "red"]}
+
+    dem_map.addLayer(dem_image, vis_params, "DEM")
+    dem_map.add_colorbar(colors=vis_params["palette"], vmin=vis_params["min"], vmax=vis_params["max"], caption="Elevation (m)")
+    dem_map.addLayerControl()
+
+    # --- Slope Map ---
+    slope_map = gee_folium.Map(add_google_map=True) # Add basemap for context
+    slope_map.centerObject(ee_geometry)
+
+    slope_image = ee.Terrain.slope(dem_image)
+    slope_vis_params = {"min": 0, "max": 60, "palette": ["blue", "green", "yellow", "red"]}
+
+    slope_map.addLayer(slope_image, slope_vis_params, "Slope")
+    slope_map.add_colorbar(colors=slope_vis_params["palette"], vmin=0, vmax=60, caption="Slope (degrees)")
+    slope_map.addLayerControl()
+
+    return dem_map._repr_html_(), slope_map._repr_html_()
+
 def add_indices(image, nir_band, red_band, blue_band, green_band, swir1_band, swir2_band, evi_vars):
     """Calculates and adds multiple vegetation indices to an Earth Engine image."""
     # It's safer to work with the image bands directly
@@ -291,7 +329,7 @@ WAYBACK_DF = get_wayback_data()
 def process_and_display(file_obj, url_str, buffer_m, progress=gr.Progress()):
     """Main function to process the uploaded file or URL and generate initial outputs."""
     if file_obj is None and not (url_str and url_str.strip()):
-        return None, "Please upload a file or provide a URL.", None, None, None
+        return None, "Please upload a file or provide a URL.", None, None, None, None, None
 
     progress(0, desc="Reading and processing geometry...")
     try:
@@ -313,7 +351,7 @@ def process_and_display(file_obj, url_str, buffer_m, progress=gr.Progress()):
                 break
 
         if geometry_gdf is None:
-            return None, "No valid polygon found in the provided file or URL.", None, None, None
+            return None, "No valid polygon found in the provided file or URL.", None, None, None, None, None
 
         geometry_gdf = to_best_crs(geometry_gdf)
 
@@ -326,16 +364,23 @@ def process_and_display(file_obj, url_str, buffer_m, progress=gr.Progress()):
         )
 
     except Exception as e:
-        return None, f"Error processing file: {e}", None, None, None
+        return None, f"Error processing file: {e}", None, None, None, None, None
+
+    progress(0.5, desc="Generating maps and stats...")
+    
+    # Convert to EE geometry
+    ee_geometry = ee.Geometry(json.loads(geometry_gdf.to_crs(4326).to_json())['features'][0]['geometry'])
+
+    # Generate DEM and Slope maps
+    dem_html, slope_html = get_dem_slope_maps(ee_geometry)
 
-    progress(0.5, desc="Generating map and stats...")
 
-    # Create map
+    # Create main map
     m = folium.Map()
     
     if not WAYBACK_DF.empty:
         # The DataFrame is already sorted by date, so the last item is the latest.
-        latest_item = WAYBACK_DF.iloc[-1]
+        latest_item = WAYBACK_DF.iloc[0]
         wayback_url = (
             latest_item["ResourceURL_Template"]
             .replace("{TileMatrixSet}", "GoogleMapsCompatible")
@@ -373,7 +418,7 @@ def process_and_display(file_obj, url_str, buffer_m, progress=gr.Progress()):
     buffer_geometry_json = buffer_geometry_gdf.to_json()
 
     progress(1, desc="Done!")
-    return m._repr_html_(), None, stats_df, geometry_json, buffer_geometry_json
+    return m._repr_html_(), None, stats_df, dem_html, slope_html, geometry_json, buffer_geometry_json
 
 
 def calculate_indices(
@@ -520,6 +565,12 @@ with gr.Blocks(theme=gr.themes.Soft(), title="Kamlan: KML Analyzer") as demo:
             gr.Markdown("## 2. Results")
             stats_output = gr.DataFrame(label="Geometry Metrics")
             map_output = gr.HTML(label="Map View")
+            
+            gr.Markdown("### Digital Elevation Model (DEM) and Slope")
+            with gr.Row():
+                dem_map_output = gr.HTML(label="DEM Map")
+                slope_map_output = gr.HTML(label="Slope Map")
+
             results_info_box = gr.Textbox(label="Calculation Status", interactive=False)
             timeseries_table = gr.DataFrame(label="Time Series Data")
             plot_output = gr.Plot(label="Time Series Plot")
@@ -537,7 +588,7 @@ with gr.Blocks(theme=gr.themes.Soft(), title="Kamlan: KML Analyzer") as demo:
     process_button.click(
         fn=process_and_display,
         inputs=[file_input, url_input, buffer_input],
-        outputs=[map_output, info_box, stats_output, geometry_data, buffer_geometry_data]
+        outputs=[map_output, info_box, stats_output, dem_map_output, slope_map_output, geometry_data, buffer_geometry_data]
     )
 
     def calculate_wrapper(geometry_json, buffer_geometry_json, veg_indices,
@@ -563,6 +614,10 @@ with gr.Blocks(theme=gr.themes.Soft(), title="Kamlan: KML Analyzer") as demo:
             # Select the first plot to display, if any exist
             first_plot = plots[0] if plots else None
             
+            # Round the dataframe to 3 decimal places for display
+            if df is not None:
+                df = df.round(3)
+
             # Return a clean set of outputs for the UI
             return status_message, df, first_plot
 
@@ -590,3 +645,4 @@ with gr.Blocks(theme=gr.themes.Soft(), title="Kamlan: KML Analyzer") as demo:
 
 if __name__ == "__main__":
     demo.launch(debug=True)
+