结果可视化（原图是动态的，这里只放某一时刻的截图）：
代码：
#!/usr/bin/env python
# Translated from Hanoi.cxx.
import vtk
class GV(object):
"""
Used to store global variables.
"""
def __init__(self, numberOfPucks=5, numberOfSteps=5, puckResolution=48, configuration=0):
self.numberOfPucks = numberOfPucks
self.numberOfSteps = numberOfSteps
self.puckResolution = puckResolution
self.configuration = configuration
self.gotFigure2 = False # Used to bail out of recursion if configuration == 2.
self.L = 1.0 # Puck height.
self.H = 1.1 * self.numberOfPucks * self.L # Peg height.
self.R = 0.5 # Peg radius.
self.rMin = 4.0 * self.R # The minimum allowable radius of disks.
self.rMax = 12.0 * self.R # The maximum allowable radius of disks
self.D = 1.1 * 1.25 * self.rMax # The distance between the pegs.
self.numberOfMoves = 0
def update(self, numberOfPucks, numberOfSteps, puckResolution, configuration):
self.numberOfPucks = numberOfPucks
self.numberOfSteps = numberOfSteps
self.puckResolution = puckResolution
self.configuration = configuration
self.H = 1.1 * self.numberOfPucks * self.L # Peg height.
# Globals
gv = GV()
renWin = vtk.vtkRenderWindow()
"""
For pegStack we use a list of lists where the sublists correspond to the
source, target and helper pegs.
Python lists can be used as a stack since they have append() (corresponding
to push()) and pop().
"""
pegStack = [[], [], []]
def hanoi():
colors = vtk.vtkNamedColors()
# Create the renderer and render window interactor.
ren = vtk.vtkRenderer()
renWin.AddRenderer(ren)
renWin.SetSize(1200, 750)
iren = vtk.vtkRenderWindowInteractor()
iren.SetRenderWindow(renWin)
ren.SetBackground(colors.GetColor3d("PapayaWhip"))
camera = vtk.vtkCamera()
camera.SetPosition(41.0433, 27.9637, 30.442)
camera.SetFocalPoint(11.5603, -1.51931, 0.95899)
camera.SetClippingRange(18.9599, 91.6042)
camera.SetViewUp(0, 1, 0)
ren.SetActiveCamera(camera)
# Create geometry: table, pegs, and pucks.
pegGeometry = vtk.vtkCylinderSource()
pegGeometry.SetResolution(8)
pegMapper = vtk.vtkPolyDataMapper()
pegMapper.SetInputConnection(pegGeometry.GetOutputPort())
puckGeometry = vtk.vtkCylinderSource()
puckGeometry.SetResolution(gv.puckResolution)
puckMapper = vtk.vtkPolyDataMapper()
puckMapper.SetInputConnection(puckGeometry.GetOutputPort())
tableGeometry = vtk.vtkPlaneSource()
tableGeometry.SetResolution(10, 10)
tableMapper = vtk.vtkPolyDataMapper()
tableMapper.SetInputConnection(tableGeometry.GetOutputPort())
# Create the actors: table top, pegs, and pucks
# The table
table = vtk.vtkActor()
ren.AddActor(table)
table.SetMapper(tableMapper)
# table.GetProperty().SetColor(0.9569, 0.6431, 0.3765)
table.GetProperty().SetColor(colors.GetColor3d("SaddleBrown"))
table.AddPosition(gv.D, 0, 0)
table.SetScale(4 * gv.D, 2 * gv.D, 3 * gv.D)
table.RotateX(90)
# The pegs (using cylinder geometry). Note that the pegs have to translated
# in the y-direction because the cylinder is centered about the origin.
gv.H = 1.1 * gv.numberOfPucks * gv.L
peg = list()
for i in range(0, 3):
peg.append(vtk.vtkActor())
ren.AddActor(peg[i])
peg[i].SetMapper(pegMapper)
# peg[i].GetProperty().SetColor(1, 1, 1)
peg[i].GetProperty().SetColor(colors.GetColor3d("Lavender"))
peg[i].AddPosition(i * gv.D, gv.H / 2, 0)
peg[i].SetScale(1, gv.H, 1)
# The pucks (using cylinder geometry). Always loaded on peg# 0.
puck = list()
randomSequence = vtk.vtkMinimalStandardRandomSequence()
randomSequence.SetSeed(1)
for i in range(0, gv.numberOfPucks):
puck.append(vtk.vtkActor())
puck[i].SetMapper(puckMapper)
color = [0, 0, 0]
for j in range(0, 3):
color[j] = randomSequence.GetValue()
randomSequence.Next()
puck[i].GetProperty().SetColor(*color)
puck[i].AddPosition(0, i * gv.L + gv.L / 2, 0)
scale = gv.rMax - i * (gv.rMax - gv.rMin) / (gv.numberOfPucks - 1)
puck[i].SetScale(scale, 1, scale)
ren.AddActor(puck[i])
pegStack[0].append(puck[i])
# Reset the camera to view all actors.
renWin.Render()
renWin.SetWindowName("Towers of Hanoi")
if gv.configuration == 3:
WriteImage("hanoi0.png", renWin, rgba=False)
if gv.configuration != 1:
# Begin recursion.
Hanoi(gv.numberOfPucks - 1, 0, 2, 1)
Hanoi(1, 0, 1, 2)
if not gv.gotFigure2:
Hanoi(gv.numberOfPucks - 1, 2, 1, 0)
renWin.Render()
if gv.configuration == 3:
WriteImage("hanoi2.png", renWin, rgba=False)
# Report output.
s = 'Number of moves: {:d}\nPolygons rendered each frame: {:d}\nTotal number of frames: {:d}'
print(s.format(gv.numberOfMoves, 3 * 8 + 1 + gv.numberOfPucks * (2 + gv.puckResolution),
gv.numberOfMoves * 3 * gv.numberOfSteps))
iren.AddObserver('EndInteractionEvent', OrientationObserver(ren.GetActiveCamera()))
# Render the image.
iren.Initialize()
iren.Start()
def main():
maxPucks = 20
if not verify_parameters(maxPucks):
return
hanoi()
def get_program_parameters():
import argparse
description = 'Towers of Hanoi. .'
epilogue = '''
Where: -p specifies the number of pucks.
-s specifies the number of steps.
-r specifies the puck resolution.
-c specifies configuration.
0 final configuration.
1 initial configuration.
2 intermediate configuration.
3 final configuration and save images
Defaults: -p 5 -s 5 -r 48 -c 0
'''
parser = argparse.ArgumentParser(description=description, epilog=epilogue,
formatter_class=argparse.RawDescriptionHelpFormatter)
parser.add_argument('--numberOfPucks', '-p', default=5, type=int, nargs='?', help='The number of pucks.')
parser.add_argument('--numberOfSteps', '-s', default=5, type=int, nargs='?', help='The number of steps.')
parser.add_argument('--puckResolution', '-r', default=48, type=int, nargs='?', help='The puck resolution.')
parser.add_argument('--configuration', '-c', default=0, type=int, nargs='?', help='The configuration.')
args = parser.parse_args()
return args.numberOfPucks, args.numberOfSteps, args.puckResolution, args.configuration
def verify_parameters(maxPucks):
numberOfPucks, numberOfSteps, puckResolution, configuration = get_program_parameters()
numberOfPucks = abs(numberOfPucks)
numberOfSteps = abs(numberOfSteps)
puckResolution = abs(puckResolution)
configuration = abs(configuration)
check = True
if numberOfPucks < 2:
print('Please use more pucks!')
check = False
if numberOfPucks > maxPucks:
print('Too many pucks specified! Maximum is', maxPucks)
check = False
if numberOfSteps < 3:
print('Please use more steps!')
check = False
if configuration > 3:
print('0 >= configuration <= 3')
check = False
if check:
gv.update(numberOfPucks, numberOfSteps, puckResolution, configuration)
return check
def MovePuck(peg1, peg2):
"""
This routine is responsible for moving pucks from peg1 to peg2.
:param peg1: Initial peg.
:param peg2: Final peg.
:return:
"""
gv.numberOfMoves += 1
# Get the actor to move
movingActor = pegStack[peg1].pop()
# Get the distance to move up.
distance = (gv.H - (gv.L * (len(pegStack[peg1]) - 1)) + gv.rMax) / gv.numberOfSteps
for i in range(0, gv.numberOfSteps):
movingActor.AddPosition(0, distance, 0)
renWin.Render()
# Get the distance to move across
distance = (peg2 - peg1) * gv.D / gv.numberOfSteps
flipAngle = 180.0 / gv.numberOfSteps
for i in range(0, gv.numberOfSteps):
movingActor.AddPosition(distance, 0, 0)
movingActor.RotateX(flipAngle)
renWin.Render()
if gv.numberOfMoves == 13 and i == 3: # for making book image
if gv.configuration == 3 or gv.configuration == 2:
cam = renWin.GetRenderers().GetFirstRenderer().GetActiveCamera()
camera1 = vtk.vtkCamera()
camera1.SetPosition(54.7263, 41.6467, 44.125)
camera1.SetFocalPoint(11.5603, -1.51931, 0.95899)
camera1.SetClippingRange(42.4226, 115.659)
camera1.SetViewUp(0, 1, 0)
renWin.GetRenderers().GetFirstRenderer().SetActiveCamera(camera1)
renWin.Render()
if gv.configuration == 3:
WriteImage("hanoi1.png", renWin, rgba=False)
if gv.configuration == 2:
gv.gotFigure2 = True
break
renWin.GetRenderers().GetFirstRenderer().SetActiveCamera(cam)
renWin.Render()
if gv.gotFigure2:
pegStack[peg2].append(movingActor)
return
# Get the distance to move down.
distance = ((gv.L * (len(pegStack[peg2]) - 1)) - gv.H - gv.rMax) / gv.numberOfSteps
for i in range(0, gv.numberOfSteps):
movingActor.AddPosition(0, distance, 0)
renWin.Render()
pegStack[peg2].append(movingActor)
def Hanoi(n, peg1, peg2, peg3):
"""
Tower of Hanoi.
:param n: Number of disks.
:param peg1: Source
:param peg2: Target
:param peg3: Helper
:return:
"""
# If gotFigure2 is true, we break out of the recursion.
if gv.gotFigure2:
return
if n != 1:
Hanoi(n - 1, peg1, peg3, peg2)
if gv.gotFigure2:
return
Hanoi(1, peg1, peg2, peg3)
Hanoi(n - 1, peg3, peg2, peg1)
else:
MovePuck(peg1, peg2)
class OrientationObserver(object):
def __init__(self, cam):
self.cam = cam
def __call__(self, caller, ev):
# Just do this to demonstrate who called callback and the event that triggered it.
print(caller.GetClassName(), "Event Id:", ev)
# Now print the camera orientation.
CameraOrientation(self.cam)
def CameraOrientation(cam):
fmt1 = "{:>15s}"
fmt2 = "{:9.6g}"
print(fmt1.format("Position:"), ', '.join(map(fmt2.format, cam.GetPosition())))
print(fmt1.format("Focal point:"), ', '.join(map(fmt2.format, cam.GetFocalPoint())))
print(fmt1.format("Clipping range:"), ', '.join(map(fmt2.format, cam.GetClippingRange())))
print(fmt1.format("View up:"), ', '.join(map(fmt2.format, cam.GetViewUp())))
print(fmt1.format("Distance:"), fmt2.format(cam.GetDistance()))
def WriteImage(fileName, renWin1, rgba=True):
"""
Write the render window view to an image file.
Image types supported are:
BMP, JPEG, PNM, PNG, PostScript, TIFF.
The default parameters are used for all writers, change as needed.
:param fileName: The file name, if no extension then PNG is assumed.
:param renWin1: The render window.
:param rgba: Used to set the buffer type.
:return:
"""
import os
if fileName:
# Select the writer to use.
path, ext = os.path.splitext(fileName)
ext = ext.lower()
if not ext:
ext = '.png'
fileName = fileName + ext
if ext == '.bmp':
writer = vtk.vtkBMPWriter()
elif ext == '.jpg':
writer = vtk.vtkJPEGWriter()
elif ext == '.pnm':
writer = vtk.vtkPNMWriter()
elif ext == '.ps':
if rgba:
rgba = False
writer = vtk.vtkPostScriptWriter()
elif ext == '.tiff':
writer = vtk.vtkTIFFWriter()
else:
writer = vtk.vtkPNGWriter()
windowto_image_filter = vtk.vtkWindowToImageFilter()
windowto_image_filter.SetInput(renWin1)
windowto_image_filter.SetScale(1) # image quality
if rgba:
windowto_image_filter.SetInputBufferTypeToRGBA()
else:
windowto_image_filter.SetInputBufferTypeToRGB()
# Read from the front buffer.
windowto_image_filter.ReadFrontBufferOff()
windowto_image_filter.Update()
writer.SetFileName(fileName)
writer.SetInputConnection(windowto_image_filter.GetOutputPort())
writer.Write()
else:
raise RuntimeError('Need a filename.')
if __name__ == '__main__':
main()