added land

api/app/services/link.py

@@ -1,19 +1,29 @@
-from app.core.geo import GeoPoint
+from app.core.geo import GeoPoint, sample_path
 from app.core.propagation import manual_link_budget
 from app.models.link import LinkBudgetRequest, LinkBudgetResponse
+from app.services.vegetation import vegetation_loss_along
 
 
 def link_budget(request: LinkBudgetRequest) -> LinkBudgetResponse:
     if request.model != "manual":
         raise NotImplementedError(f"{request.model} link model is implemented in a later stage")
 
+    tx = GeoPoint(lat=request.tx.lat, lon=request.tx.lon)
+    rx = GeoPoint(lat=request.rx.lat, lon=request.rx.lon)
+    points = sample_path(tx, rx, 256)
+    vegetation_db = vegetation_loss_along(
+        points,
+        freq_hz=request.frequency_mhz * 1_000_000,
+        include_vegetation=request.include_vegetation,
+    )
     budget = manual_link_budget(
-        tx=GeoPoint(lat=request.tx.lat, lon=request.tx.lon),
-        rx=GeoPoint(lat=request.rx.lat, lon=request.rx.lon),
+        tx=tx,
+        rx=rx,
         tx_power_dbm=request.tx.power_dbm,
         tx_gain_dbi=request.tx.gain_dbi,
         rx_gain_dbi=request.rx.gain_dbi,
         sensitivity_dbm=request.rx.sensitivity_dbm,
         frequency_mhz=request.frequency_mhz,
+        vegetation_db=vegetation_db,
     )
     return LinkBudgetResponse(**budget.__dict__)

api/app/services/terrain.py

@@ -20,6 +20,7 @@ from app.models.terrain import (
     TerrainProfileResponse,
 )
 from app.services import buildings as buildings_service
+from app.services.vegetation import vegetation_loss_along
 
 
 def elevation_at(lat: float, lon: float, surface: str) -> ElevationResponse:
@@ -101,6 +102,11 @@ def los(
         request.rx.height_agl,
         request.frequency_mhz * 1_000_000,
     )
+    vegetation_loss = vegetation_loss_along(
+        points,
+        freq_hz=request.frequency_mhz * 1_000_000,
+        include_vegetation=request.include_vegetation,
+    )
 
     def convert(sample: LosSample) -> Obstruction:
         return Obstruction(
@@ -131,6 +137,7 @@ def los(
         geometric_obstructions_count=len(geometric_obstructions),
         building_obstructions_count=len(building_obstructions),
         diffraction_loss_db=diffraction_loss,
+        vegetation_loss_db=vegetation_loss,
         profile_ref=f"inline:{profile_request.samples}",
     )
 

api/app/services/vegetation.py

@@ -0,0 +1,39 @@
+from __future__ import annotations
+
+from pathlib import Path
+
+from app.config import get_settings
+from app.core.geo import PathPoint
+from app.core.landcover import LandcoverNotConfiguredError, landcover_path
+from app.core.vegetation import P833Coefficients, p833_attenuation
+
+
+def vegetation_loss_along(
+    points: list[PathPoint],
+    freq_hz: float,
+    include_vegetation: bool,
+    landcover_path_dir: str | Path | None = None,
+    canopy_path_dir: str | Path | None = None,
+) -> float:
+    if not include_vegetation:
+        return 0.0
+
+    settings = get_settings()
+    landcover_dir = landcover_path_dir or settings.landcover_path
+    canopy_dir = canopy_path_dir or settings.canopy_path
+
+    try:
+        path = landcover_path(points, landcover_dir, canopy_dir)
+    except LandcoverNotConfiguredError:
+        return 0.0
+
+    coefficients = P833Coefficients(
+        gamma_db_per_m=settings.p833_gamma_db_per_m,
+        max_attenuation_db=settings.p833_max_attenuation_db,
+    )
+    return p833_attenuation(
+        depth_m=path.vegetation_depth_m,
+        freq_hz=freq_hz,
+        forest_type="unknown",
+        coefficients=coefficients,
+    )