@mytec: iter2.4 ready for testing

backend/app/api/routes/terrain.py

@@ -1,4 +1,6 @@
 import os
+import asyncio
+import math
 
 from fastapi import APIRouter, HTTPException, Query
 from fastapi.responses import FileResponse
@@ -11,6 +13,46 @@ from app.services.los_service import los_service
 router = APIRouter()
 
 
+def _build_elevation_grid(min_lat, max_lat, min_lon, max_lon, resolution):
+    """Build a 2D elevation grid. Runs in thread executor (CPU-bound)."""
+    import numpy as np
+
+    rows = min(resolution, 200)
+    cols = min(resolution, 200)
+
+    lats = np.linspace(max_lat, min_lat, rows)   # north to south
+    lons = np.linspace(min_lon, max_lon, cols)
+
+    grid = []
+    min_elev = float('inf')
+    max_elev = float('-inf')
+
+    for lat in lats:
+        row = []
+        for lon in lons:
+            elev = terrain_service.get_elevation_sync(float(lat), float(lon))
+            row.append(elev)
+            if elev < min_elev:
+                min_elev = elev
+            if elev > max_elev:
+                max_elev = elev
+        grid.append(row)
+
+    return {
+        "grid": grid,
+        "rows": rows,
+        "cols": cols,
+        "min_elevation": min_elev if min_elev != float('inf') else 0,
+        "max_elevation": max_elev if max_elev != float('-inf') else 0,
+        "bbox": {
+            "min_lat": min_lat,
+            "max_lat": max_lat,
+            "min_lon": min_lon,
+            "max_lon": max_lon,
+        },
+    }
+
+
 @router.get("/elevation")
 async def get_elevation(
     lat: float = Query(..., ge=-90, le=90, description="Latitude"),
@@ -26,6 +68,42 @@ async def get_elevation(
     }
 
 
+@router.get("/elevation-grid")
+async def get_elevation_grid(
+    min_lat: float = Query(..., ge=-90, le=90, description="South boundary"),
+    max_lat: float = Query(..., ge=-90, le=90, description="North boundary"),
+    min_lon: float = Query(..., ge=-180, le=180, description="West boundary"),
+    max_lon: float = Query(..., ge=-180, le=180, description="East boundary"),
+    resolution: int = Query(100, ge=10, le=200, description="Grid size (rows/cols)"),
+):
+    """Get elevation grid for a bounding box. Returns a 2D array for terrain visualization."""
+    if max_lat <= min_lat or max_lon <= min_lon:
+        raise HTTPException(400, "Invalid bbox: max must be greater than min")
+    if (max_lat - min_lat) > 2.0 or (max_lon - min_lon) > 2.0:
+        raise HTTPException(400, "Bbox too large (max 2 degrees per axis)")
+
+    # Ensure terrain tiles are loaded for this area
+    await terrain_service.ensure_tiles_for_bbox(min_lat, min_lon, max_lat, max_lon)
+
+    # Pre-load all tiles that cover the bbox
+    lat_start = int(math.floor(min_lat))
+    lat_end = int(math.floor(max_lat))
+    lon_start = int(math.floor(min_lon))
+    lon_end = int(math.floor(max_lon))
+    for lat_i in range(lat_start, lat_end + 1):
+        for lon_i in range(lon_start, lon_end + 1):
+            tile_name = terrain_service.get_tile_name(lat_i + 0.5, lon_i + 0.5)
+            terrain_service._load_tile(tile_name)
+
+    # Build grid in thread executor (CPU-bound sync calls)
+    loop = asyncio.get_event_loop()
+    result = await loop.run_in_executor(
+        None, _build_elevation_grid,
+        min_lat, max_lat, min_lon, max_lon, resolution,
+    )
+    return result
+
+
 @router.get("/profile")
 async def get_elevation_profile(
     lat1: float = Query(..., description="Start latitude"),
@@ -87,9 +165,9 @@ async def check_fresnel_clearance(
 @router.get("/tiles")
 async def list_cached_tiles():
     """List cached SRTM tiles"""
-    tiles = list(terrain_service.cache_dir.glob("*.hgt"))
+    tiles = list(terrain_service.terrain_path.glob("*.hgt"))
     return {
-        "cache_dir": str(terrain_service.cache_dir),
+        "cache_dir": str(terrain_service.terrain_path),
         "tiles": [t.stem for t in tiles],
         "count": len(tiles)
     }