added formulas

api/app/services/terrain.py

@@ -10,10 +10,10 @@ from sqlalchemy.orm import Session
 
 from app.config import get_settings
 from app.core import dem
-from app.core.diffraction import deygout
+from app.core.diffraction import bullington_equivalent_loss
 from app.core.fresnel import LosSample, los_analysis
 from app.core.geo import GeoPoint, PathPoint, linestring_geojson, sample_path
-from app.core.raster_sampling import raster_files
+from app.core.raster_sampling import RasterNotConfiguredError, raster_files, sample_along
 from app.core.surface import SurfaceProfile, build_surface_profile
 from app.models.common import DataSources
 from app.models.terrain import (
@@ -67,6 +67,8 @@ def terrain_profile(
             dem_used=bool(raster_files(get_settings().dem_path)),
             include_buildings=request.include_buildings,
             db=db,
+            canopy_used=request.include_canopy
+            and bool(raster_files(get_settings().canopy_path)),
         ),
     )
 
@@ -103,11 +105,12 @@ def los(
         request.fresnel_clearance,
         request.k_factor,
     )
-    diffraction_loss = deygout(
+    diffraction_loss = bullington_equivalent_loss(
         surface_profile,
         request.tx.height_agl,
         request.rx.height_agl,
         request.frequency_mhz * 1_000_000,
+        k=request.k_factor,
     )
     vegetation_loss = vegetation_loss_along(
         points,
@@ -247,6 +250,24 @@ def _building_heights(
         return None
 
 
+def _canopy_heights(points: list[PathPoint], include_canopy: bool) -> list[float] | None:
+    if not include_canopy:
+        return None
+    try:
+        values = sample_along(
+            points,
+            get_settings().canopy_path,
+            "canopy",
+            require_all=False,
+        )
+    except RasterNotConfiguredError:
+        return None
+
+    values = np.nan_to_num(values, nan=0.0, posinf=0.0, neginf=0.0)
+    values = np.maximum(values, 0.0)
+    return values.tolist()
+
+
 def surface_profile_from_points(
     points: list[PathPoint],
     include_buildings: bool,
@@ -259,10 +280,12 @@ def surface_profile_from_points(
         ground_elevations = np.zeros(len(points), dtype=float).tolist()
 
     building_heights = _building_heights(points, include_buildings, db)
+    canopy_heights = _canopy_heights(points, include_canopy)
     return build_surface_profile(
         points,
         ground_elevations=ground_elevations,
         building_heights=building_heights,
+        canopy_heights=canopy_heights,
         include_buildings=include_buildings,
         include_canopy=include_canopy,
     )