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examples/trainval.py

@@ -113,6 +113,7 @@ if __name__ == "__main__":
             occupancy values with shape (N, 1).
         """
         density_after_activation = radiance_field.query_density(x)
+        # those two are similar when density is small.
         # occupancy = 1.0 - torch.exp(-density_after_activation * render_step_size)
         occupancy = density_after_activation * render_step_size
         return occupancy