@T4mmi, you may benefit from checking out PyVista’s interface to VTK to make working with your VTK dataset a bit easier. Here’s an example with the numpy array you shared:
import pyvista as pv
import numpy as np
pts = np.random.rand(512*3).reshape(-1,3)
# Make vtkPolyData of the points array
point_cloud = pv.PolyData(pts)
point_cloud.plot(render_points_as_spheres=True, point_size=10)
# runs the delaunay 3D algorithm
mesh = point_cloud.delaunay_3d(alpha=0.25)
# Make a wireframe with some data
wires = mesh.compute_cell_sizes(length=False, area=False, volume=True).wireframe()
# Plot it
wires.plot(line_width=2)
