code: import numpy as np
  from prnet.utils.render import vis_of_vertices, render_texture
  from scipy import ndimage
  
  def get_visibility(vertices, triangles, h, w):
      triangles = triangles.T
      vertices_vis = vis_of_vertices(vertices.T, triangles, h, w)
      vertices_vis = vertices_vis.astype(bool)
      for k in range(2):
          tri_vis = vertices_vis[triangles[0,:]] | vertices_vis[triangles[1,:]] | vertices_vis[triangles[2,:]]
          ind = triangles[:, tri_vis]
          vertices_vis[ind] = True
      # for k in range(2):
      #     tri_vis = vertices_vis[triangles[0,:]] & vertices_vis[triangles[1,:]] & vertices_vis[triangles[2,:]]
      #     ind = triangles[:, tri_vis]
      #     vertices_vis[ind] = True
      vertices_vis = vertices_vis.astype(np.float32)  #1 for visible and 0 for non-visible
      return vertices_vis
  
  def get_uv_mask(vertices_vis, triangles, uv_coords, h, w, resolution):
      triangles = triangles.T
      vertices_vis = vertices_vis.astype(np.float32)
      uv_mask = render_texture(uv_coords.T, vertices_vis[np.newaxis, :], triangles, resolution, resolution, 1)
      uv_mask = np.squeeze(uv_mask > 0)
      uv_mask = ndimage.binary_closing(uv_mask)
      uv_mask = ndimage.binary_erosion(uv_mask, structure = np.ones((4,4)))  
      uv_mask = ndimage.binary_closing(uv_mask)
      uv_mask = ndimage.binary_erosion(uv_mask, structure = np.ones((4,4)))  
      uv_mask = ndimage.binary_erosion(uv_mask, structure = np.ones((4,4)))  
      uv_mask = ndimage.binary_erosion(uv_mask, structure = np.ones((4,4)))  
      uv_mask = uv_mask.astype(np.float32)
  
      return np.squeeze(uv_mask)
  
  def get_depth_image(vertices, triangles, h, w, isShow = False):
      z = vertices[:, 2:]
      if isShow:
          z = z/max(z)
      depth_image = render_texture(vertices.T, z.T, triangles.T, h, w, 1)
      return np.squeeze(depth_image)
apis: scipy.ndimage.binary_closing numpy.ones numpy.squeeze