added comments

vlfm/mapping/base_map.py

@@ -42,6 +42,8 @@ def _xy_to_px(self, points: np.ndarray) -> np.ndarray:
             The array of (x, y) pixel coordinates.
         """
         px = np.rint(points[:, ::-1] * self.pixels_per_meter) + self._episode_pixel_origin
+
+        #Flips y axis
         px[:, 0] = self._map.shape[0] - px[:, 0]
         return px.astype(int)
 

vlfm/mapping/object_point_cloud_map.py

@@ -59,6 +59,7 @@ def update_map(
             # assigned with a random number so that they can be identified later.
             within_range = within_range.astype(np.float32)
             within_range[within_range == 0] = np.random.rand()
+
         global_cloud = transform_points(tf_camera_to_episodic, local_cloud)
         global_cloud = np.concatenate((global_cloud, within_range[:, None]), axis=1)
 

vlfm/mapping/obstacle_map.py

@@ -4,6 +4,9 @@
 
 import cv2
 import numpy as np
+
+#TODO: Where to get these from?
+# These involve getting frontiers and updating explored areas
 from frontier_exploration.frontier_detection import detect_frontier_waypoints
 from frontier_exploration.utils.fog_of_war import reveal_fog_of_war
 
@@ -88,8 +91,12 @@ def update_map(
                 filled_depth = depth.copy()
                 filled_depth[depth == 0] = 1.0
             else:
+                #TODO: Why do this?
                 filled_depth = fill_small_holes(depth, self._hole_area_thresh)
+
             scaled_depth = filled_depth * (max_depth - min_depth) + min_depth
+
+            #Mask is used to ignore max_depth pixels
             mask = scaled_depth < max_depth
             point_cloud_camera_frame = get_point_cloud(scaled_depth, mask, fx, fy)
             point_cloud_episodic_frame = transform_points(tf_camera_to_episodic, point_cloud_camera_frame)

vlfm/mapping/traj_visualizer.py

@@ -107,8 +107,13 @@ def draw_circle(self, img: np.ndarray, position: np.ndarray, **kwargs: Any) -> n
 
     def _metric_to_pixel(self, pt: np.ndarray) -> np.ndarray:
         """Converts a metric coordinate to a pixel coordinate"""
+
+        #TODO: Changed y-flip
+        #Why flip both x and y axes?  Aren't we supposed to flip only the y axis?
+        px =  pt * self._pixels_per_meter * np.array([1, -1]) + self._origin_in_img
+
         # Need to flip y-axis because pixel coordinates start from top left
-        px = pt * self._pixels_per_meter * np.array([-1, -1]) + self._origin_in_img
+        #px = pt * self._pixels_per_meter * np.array([-1, -1]) + self._origin_in_img
         # px = pt * self._pixels_per_meter + self._origin_in_img
         px = px.astype(np.int32)
         return px

vlfm/utils/habitat_visualizer.py

@@ -219,6 +219,7 @@ def sim_xy_to_grid_xy(
     )
     grid_xy = ((sim_xy - lower_bound[::-1]) / grid_size).astype(int)
 
+    #Removes duplicate rows
     if remove_duplicates:
         grid_xy = np.unique(grid_xy, axis=0)