Invert radius steps, multiplier for mesh DSM, density checks

opendm/dem/commands.py

@@ -373,10 +373,9 @@ def window_filter_2d(arr, nodata, window, kernel_size, filter):
     return win_arr
 
 
-def get_dem_radius_steps(stats_file, steps, resolution):
-    radius_steps = [point_cloud.get_density(stats_file, resolution)]
+def get_dem_radius_steps(stats_file, steps, resolution, multiplier = 1.0):
+    radius_steps = [point_cloud.get_density(stats_file, resolution) * multiplier]
     for _ in range(steps - 1):
-        radius_steps.append(radius_steps[-1] / math.sqrt(2)) # sqrt(2) is arbitrary, maybe there's a better value?
-    radius_steps.reverse()
-
+        radius_steps.append(radius_steps[-1] * math.sqrt(2)) # sqrt(2) is arbitrary, maybe there's a better value?
+    
     return radius_steps

opendm/mesh.py

@@ -20,7 +20,7 @@ def create_25dmesh(inPointCloud, outMesh, filtered_point_cloud_stats, dsm_resolu
     os.mkdir(tmp_directory)
     log.ODM_INFO('Created temporary directory: %s' % tmp_directory)
 
-    radius_steps = commands.get_dem_radius_steps(filtered_point_cloud_stats, 3, dsm_resolution)
+    radius_steps = commands.get_dem_radius_steps(filtered_point_cloud_stats, 3, dsm_resolution, multiplier=math.sqrt(2))
 
     log.ODM_INFO('Creating DSM for 2.5D mesh')
 

opendm/point_cloud.py

@@ -120,7 +120,11 @@ def get_density(stats_file, resolution_fallback=5.0):
     with open(stats_file, 'r') as f:
         j = json.loads(f.read())
         if "density" in j:
-            return round(j["density"], 3)
+            d = j["density"]
+            if d > 0:
+                return round(d, 3)
+            else:
+                return fallback()
         else:
             return fallback()