fix(plt): avoid occlusion order problem

depthy/misc/plots.py

@@ -35,25 +35,29 @@ def plot_point_cloud(disp_arr: np.ndarray,
         raise IndexError('Downscale factor is %s and out-of-range.' % down_scale)
 
     # rgb image presence/absence handling
-    if rgb_img is None or disp_arr.shape[:2] != rgb_img.shape[:2]:
-        rgb = np.ones(disp_arr.shape)[::down_scale, ::down_scale, ...]
+    if rgb_img is None or disp_arr.shape[:2] != rgb_img.shape[:2] or len(rgb_img.shape) != 3:
+        rgb = np.zeros(disp_arr.shape+(3,))[::down_scale, ::down_scale, ...]
         if rgb_img is not None:
             warnings.warn('Depth map and RGB image dimension mismatch.')
     else:
         # flip x-axis and downscale rgb image
         rgb = rgb_img[:, ::-1, ...][::down_scale, ::down_scale, ...]
+        # normalize rgb values to 0-1 range
+        rgb = Normalizer(rgb).type_norm(new_min=max(0, rgb.min()), new_max=1)
 
     # flip x-axis and downscale depth map
     zz = disp_arr[:, ::-1][::down_scale, ::down_scale, ...]
     xx, yy = np.meshgrid(np.arange(zz.shape[1]), np.arange(zz.shape[0]))
 
-    # normalize rgb values to 0-1 range
-    rgb = Normalizer(rgb).type_norm(new_min=0, new_max=1)
+    # sort according to depth value to avoid occlusion order problem
+    order = np.argsort(zz.ravel())
 
     # plot depth data
     fig, ax = (plt.figure(), plt.axes(projection='3d')) if ax is None else (None, ax)
     ax.set_axis_on() if show_axes else ax.set_axis_off()
-    ax.scatter(xx, yy, zz, c=rgb.reshape(-1, rgb.shape[-1]), s=s)
+    ax.scatter(xx.ravel()[order], yy.ravel()[order], zz.ravel()[order], c=rgb.reshape(-1, rgb.shape[2])[order], s=s)
     ax.view_init(view_angles[0], view_angles[1])
+    ax.set_ylim(0, zz.shape[0])
+    ax.set_xlim(0, zz.shape[1])
 
     return ax

tests/test_plt.py

@@ -1,8 +1,9 @@
 import unittest
 import numpy as np
 import matplotlib.pyplot as plt
+import os
 
-from depthy.misc import plot_point_cloud
+from depthy.misc import plot_point_cloud, load_pfm
 
 
 class PlotDepthTestCase(unittest.TestCase):
@@ -11,6 +12,14 @@ def setUp(self):
 
         self.plot_opt = False
 
+    def test_real_data(self):
+
+        self.depth_example, _ = load_pfm(os.path.join('..', 'docs', 'img', 'pens.pfm'))
+
+        # test case with real data
+        plot_point_cloud(disp_arr=self.depth_example, rgb_img=None, down_scale=4, show_axes=True)
+        plt.show()
+
     def test_point_cloud(self):
 
         # test invalid downscale parameters