Cannot visualize the points around one of the selected points in point cloud. Not sure what I am missing. I used the below code. What it does is just takes a pointcloud and convert it into polydata and visualize it. After visualizing the pointcloud, I use mouse to select one point and calculate points around that particular point in a given radius. I am able to calculate those points but not able to visualize those. Also moving further I select 1000 random points in data and calculate their clusters too, calculate Hausdorff distances of each with original cluster and visualize the minimum distance cluster. In all this I am not able to visualize any cluster.
import vtk
import numpy as np
import open3d as o3d
import math
from numpy import random
from scipy.spatial.distance import directed_hausdorff
import vtkmodules.vtkRenderingOpenGL2
from vtkmodules.vtkCommonColor import vtkNamedColors
from vtkmodules.vtkCommonCore import vtkIdTypeArray
from vtkmodules.vtkCommonDataModel import (
vtkSelection,
vtkSelectionNode,
vtkUnstructuredGrid
)
from vtkmodules.vtkFiltersCore import vtkTriangleFilter
from vtkmodules.vtkFiltersExtraction import vtkExtractSelection
from vtkmodules.vtkFiltersSources import vtkPlaneSource
from vtkmodules.vtkInteractionStyle import vtkInteractorStyleTrackballCamera
from vtkmodules.vtkRenderingCore import (
vtkActor,
vtkCellPicker,
vtkDataSetMapper,
vtkPolyDataMapper,
vtkRenderWindow,
vtkRenderWindowInteractor,
vtkRenderer
)
class VtkPointCloud:
def __init__(self, zMin=-10.0, zMax=10.0, maxNumPoints=2e6):
# c = vtkNamedColors()
self.maxNumPoints = maxNumPoints
self.vtkPolyData = vtk.vtkPolyData()
self.clearPoints()
mapper = vtk.vtkPolyDataMapper()
mapper.SetInputData(self.vtkPolyData)
mapper.SetColorModeToDefault()
mapper.SetScalarRange(zMin, zMax)
mapper.SetScalarVisibility(1)
self.vtkActor = vtk.vtkActor()
# self.vtkActor.GetProperty().SetColor(1,1,1)
# self.vtkActor.GetProperty().SetColor(c.GetColor3d('Yellow'))
self.vtkActor.SetMapper(mapper)
def addPoint(self, point):
if self.vtkPoints.GetNumberOfPoints() < self.maxNumPoints:
pointId = self.vtkPoints.InsertNextPoint(point[:])
self.vtkDepth.InsertNextValue(point[2])
self.vtkCells.InsertNextCell(1)
self.vtkCells.InsertCellPoint(pointId)
else:
r = random.randint(0, self.maxNumPoints)
self.vtkPoints.SetPoint(r, point[:])
self.vtkCells.Modified()
self.vtkPoints.Modified()
self.vtkDepth.Modified()
def clearPoints(self):
self.vtkPoints = vtk.vtkPoints()
self.vtkCells = vtk.vtkCellArray()
self.vtkDepth = vtk.vtkDoubleArray()
self.vtkDepth.SetName('DepthArray')
self.vtkPolyData.SetPoints(self.vtkPoints)
self.vtkPolyData.SetVerts(self.vtkCells)
self.vtkPolyData.GetPointData().SetScalars(self.vtkDepth)
self.vtkPolyData.GetPointData().SetActiveScalars('DepthArray')
# Catch mouse events
class MouseInteractorStyle(vtkInteractorStyleTrackballCamera):
def __init__(self, data):
self.AddObserver('LeftButtonPressEvent', self.left_button_press_event)
self.AddObserver('RightButtonPressEvent', self.right_button_press_event)
self.data = data
self.selected_mapper = vtkDataSetMapper()
self.selected_actor = vtkActor()
self.selected_mapper2 = vtkDataSetMapper()
self.selected_actor2 = vtkActor()
self.vtk_list = vtk.vtkIdList()
self.locator = vtk.vtkPointLocator()
self.locator.SetDataSet(self.data)
self.locator.BuildLocator()
self.colors = vtkNamedColors()
def left_button_press_event(self, obj, event):
pos = self.GetInteractor().GetEventPosition()
picker = vtkCellPicker()
picker.SetTolerance(0.001)
# Pick from this location.
picker.Pick(pos[0], pos[1], 0, self.GetDefaultRenderer())
world_position = picker.GetPickPosition()
print(f'Cell id is: {picker.GetCellId()}')
# print(world_position)
self.locator.FindPointsWithinRadius(0.02,world_position, self.vtk_list)
print(self.vtk_list)
if picker.GetCellId() != -1:
print(f'Pick position is: ({world_position[0]:.6g}, {world_position[1]:.6g}, {world_position[2]:.6g})')
ids = vtkIdTypeArray()
ids.SetNumberOfComponents(1)
ids.InsertNextValue(picker.GetCellId())
# print(ids,'\n')
selection_node = vtkSelectionNode()
selection_node.SetFieldType(vtkSelectionNode.CELL)
selection_node.SetContentType(vtkSelectionNode.INDICES)
selection_node.SetSelectionList(ids)
selection = vtkSelection()
selection.AddNode(selection_node)
extract_selection = vtkExtractSelection()
extract_selection.SetInputData(0, self.data)
extract_selection.SetInputData(1, selection)
extract_selection.Update()
# In selection
selected = vtkUnstructuredGrid()
selected.ShallowCopy(extract_selection.GetOutput())
print(f'Number of points in the selection: {selected.GetNumberOfPoints()}')
# print(f'Number of cells in the selection : {selected.GetNumberOfCells()}\n')
print('########################\n')
self.selected_mapper.SetInputData(selected)
self.selected_actor.SetMapper(self.selected_mapper)
# self.selected_actor.GetProperty().EdgeVisibilityOn()
self.selected_actor.GetProperty().SetColor(self.colors.GetColor3d('Black'))
self.selected_actor.GetProperty().SetPointSize(10)
self.selected_actor.GetProperty().SetLineWidth(3)
# print(self.selected_actor)
self.GetInteractor().GetRenderWindow().GetRenderers().GetFirstRenderer().AddActor(self.selected_actor)
# Forward events
self.OnLeftButtonDown()
def right_button_press_event(self, obj, event):
if self.vtk_list.GetNumberOfIds() == 0:
return
else:
ids2 = vtkIdTypeArray()
ids2.SetNumberOfComponents(1)
for i in range(self.vtk_list.GetNumberOfIds()):
# print(i)
ids2.InsertNextValue(i)
# print(ids2)
selection_node2 = vtkSelectionNode()
selection_node2.SetFieldType(vtkSelectionNode.CELL)
selection_node2.SetContentType(vtkSelectionNode.INDICES)
selection_node2.SetSelectionList(ids2)
selection2 = vtkSelection()
selection2.AddNode(selection_node2)
extract_selection2 = vtkExtractSelection()
extract_selection2.SetInputData(0, self.data)
extract_selection2.SetInputData(1, selection2)
extract_selection2.Update()
# # In selection
selected2 = vtkUnstructuredGrid()
selected2.ShallowCopy(extract_selection2.GetOutput())
print(f'Number of neighboring points: {selected2.GetNumberOfPoints()}')
# # print(f'Number of neighboring cells: {selected2.GetNumberOfCells()}\n')
print('########################\n')
self.selected_mapper2.SetInputData(selected2)
self.selected_actor2.SetMapper(self.selected_mapper2)
# self.selected_actor.GetProperty().EdgeVisibilityOn()
self.selected_actor2.GetProperty().SetColor(self.colors.GetColor3d("tan"))
self.selected_actor2.GetProperty().SetPointSize(10)
self.selected_actor2.GetProperty().SetLineWidth(3)
# print(self.selected_actor2)
self.GetInteractor().GetRenderWindow().GetRenderers().GetFirstRenderer().AddActor(self.selected_actor2)
print('Randomly Selecting 1000 points in the data........')
point_indices = []
cluster_points = np.zeros((self.vtk_list.GetNumberOfIds(),3))
# print(cluster_points)
print('Calculating the clusters around the centers ......')
for i in range(self.vtk_list.GetNumberOfIds()):
point_indices.append(self.vtk_list.GetId(i))
cluster_points[i]=pointCloud.vtkPolyData.GetPoint(self.vtk_list.GetId(i))
point_indices = np.asarray(point_indices)
new_points= np.delete(points,point_indices, axis=0)
random_array = np.random.randint(0,new_points.shape[0],(1000))
min_haus = 1000000000.0
for i in range(random_array.shape[0]):
new_list=vtk.vtkIdList()
new_center = new_points[random_array[i]]
# print('new center to find cluster:',new_center)
self.locator.FindPointsWithinRadius(0.02,new_center, new_list)
new_cluster_points = np.zeros((new_list.GetNumberOfIds(),3))
for x in range(new_list.GetNumberOfIds()):
new_cluster_points[x]=pointCloud.vtkPolyData.GetPoint(new_list.GetId(x))
haus = directed_hausdorff(cluster_points,new_cluster_points)[0]
if haus<min_haus:
min_haus = haus
idx = random_array[i]
min_center = new_points[random_array[i]]
# print('haus:',haus)
print('min haus:',min_haus)
print('idx of min haus:',idx)
print('center of the min haus cluster:',min_center)
min_list = vtk.vtkIdList()
self.locator.FindPointsWithinRadius(0.02,min_center, min_list)
print('Min list for min center', min_list)
# # Forward events
self.OnRightButtonDown()
# Initialize point clouds
pointCloud = VtkPointCloud()
pointCloud2 = VtkPointCloud()
# print(type(pointCloud))
# Loading Point cloud using open3d
pt_cloud = o3d.io.read_point_cloud('fused_cloud_normal.ply')
points = np.asarray(pt_cloud.points)
pt_cloud2 = o3d.io.read_point_cloud('all_projected_pts.ply')
points2 = np.asarray(pt_cloud2.points)
# Adding the points into polydata
for row in points:
pointCloud.addPoint(row)
for row in points2:
pointCloud2.addPoint(row)
# Intialize actor
c = vtkNamedColors()
actor = pointCloud.vtkActor
actor.GetProperty().SetPointSize(10)
actor.GetProperty().SetColor(c.GetColor3d('Yellow'))
# actor.GetProperty().SetColor(0,0,0)
# Renderer
renderer = vtk.vtkRenderer()
renderer.AddActor(actor)
# renderer.AddActor(pointCloud2.vtkActor)
renderer.SetBackground(.1, .1, .4)
renderer.ResetCamera()
# Render Window
renderWindow = vtk.vtkRenderWindow()
renderWindow.AddRenderer(renderer)
style = MouseInteractorStyle(pointCloud.vtkPolyData)
style.SetDefaultRenderer(renderer)
# Interactor
renderWindowInteractor = vtk.vtkRenderWindowInteractor()
renderWindowInteractor.SetRenderWindow(renderWindow)
renderWindowInteractor.SetInteractorStyle(style)
# Begin Interaction
renderWindow.Render()
renderWindowInteractor.Start()
