Go to Qiita Advent Calendar 2024 Top
LoginSignup
5
7

Delete article

Deleted articles cannot be recovered.

Draft of this article would be also deleted.

Are you sure you want to delete this article?

More than 3 years have passed since last update.

@suo-takefumi(suo-takefumi)inプロトアウトスタジオ

[PyVista]調査メモ

Posted at

はじめに

PyVistaの調査メモ

image.png

環境

Window10環境で実行しました。

PS C:\> python -V
Python 3.9.5
PS C:\> pip list | Select-String "PyVista"

pyvista               0.31.3
pyvistaqt             0.5.0

ウィンドウを開きシリンダーオブジェクトを描画

image.png

import pyvista as pv
import numpy as np

targetImage = [ "image0.png" , "image1.png"]
surf = pv.Cylinder()
tex = pv.numpy_to_texture(targetImage[0])
surf.plot(texture=tex)

テクスチャ用の画像

シリンダーオブジェクトを画像出力

実行結果

image.png

png画像出力
import pyvista as pv
import numpy as np

targetImage = [ "image0.png" , "image1.png" ]
#surf = pv.Cylinder()
surf = pv.Cylinder(np.array([0, 0, 0]), np.array([0, 0, 1]), 1.0, 1.0)
"""
arg1: 座標 Location of the centroid in [x, y, z]
arg2: 向き Direction cylinder points to in [x, y, z]
arg3: 円の大きさ
arg4: 円柱の高さ 
"""
tex = pv.numpy_to_texture(targetImage[1])
plotter = pv.Plotter(off_screen=True)
plotter.add_mesh(surf , texture=tex, point_size=5.0)
plotter.screenshot('output.png')

イメージファイルの読み込み

読み込んだ画像を描画します

参考

実行結果

image.png

import pyvista as pv

targetImage = [ "image0.png" , "image1.png" ]
mesh = pv.read(targetImage[1])
mesh.plot(rgb=True, cpos="xy")

オブジェクトを2つ配置し画像出力

実行結果

image.png

import pyvista as pv
import numpy as np
plotter = pv.Plotter(off_screen=True, window_size=(400,400))

obj1 = pv.Cylinder(np.array([0, 0, 0]), np.array([0, 0, 1]), 1.0, 1.0)
plotter.add_mesh(obj1 ,color="green", show_edges=True)

obj2 = pv.Cylinder(np.array([0, 0, 1]), np.array([1, 0, 1]), 0.5, 3.0)
plotter.add_mesh(obj2 ,color="red", show_edges=True)

plotter.screenshot('output.png')

ドーナツ型オブジェクト

参照

実行結果

image.png

ウィンドウ描画
import pyvista as pv
pv.CylinderStructured(
        center=(0.0, 0.0, 0.0), 
        direction=(1.0, 0.0, 0.0), 
        radius=[2, 2.5], 
        height=3.0
    ).plot(show_edges=True)
画像出力
import pyvista as pv
obj = pv.CylinderStructured(
        center=(0.0, 0.0, 0.0), 
        direction=(1.0, 0.0, 0.0), 
        radius=[2, 2.5], 
        height=3.0
    )
plotter = pv.Plotter(off_screen=True, window_size=(400,400))
plotter.add_mesh(obj)
plotter.screenshot('output.png')

実行結果（背景透過）

image.png

画像出力(背景透明)
import pyvista as pv
pv.rcParams['transparent_background'] = True
obj = pv.CylinderStructured(
        center=(0.0, 0.0, 0.0), 
        direction=(1.0, 0.0, 0.0), 
        radius=[2, 2.5], 
        height=3.0
    )
plotter = pv.Plotter(off_screen=True, window_size=(400,400))
plotter.add_mesh(obj)
plotter.screenshot('output.png')

ブール演算

オブジェクトが重なる箇所をマスクする　※勉強中※

参考

実行結果

image.png

import pyvista as pv
import numpy as np
def make_cube():
    x = np.linspace(-0.5, 0.5, 25)
    grid = pv.StructuredGrid(*np.meshgrid(x, x, x))
    return grid.extract_surface().triangulate()

# Create to example PolyData meshes for boolean operations
sphere = pv.Sphere(radius=0.65, center=(0, 0, 0))

cube = make_cube()
union = sphere.boolean_union(cube)
p = pv.Plotter()
p.add_mesh(union,  opacity=0.5, show_edges=True, color=True)
p.show()

【NG例】オブジェクト同士が重なっていないとエラーになる

【NG例】
import pyvista as pv
import numpy as np
def make_cube():
    x = np.linspace(-0.5, 0.5, 25)
    grid = pv.StructuredGrid(*np.meshgrid(x, x, x))
    return grid.extract_surface().triangulate()

# Create to example PolyData meshes for boolean operations
sphere = pv.Sphere(radius=0.65, center=(3, 3, 3))

cube = make_cube()
union = sphere.boolean_union(cube)
p = pv.Plotter()
p.add_mesh(union,  opacity=0.5, show_edges=True, color=True)
p.show()

エラーメッセージ

PS C:\Users\user01\pyvista> python .\booltest.py
2021-08-07 17:38:47.837 (   0.135s) [                ]    vtkPointLocator.cxx:845    ERR| vtkPointLocator (000002DABCA16130): No points to subdivide
ERROR:root:No points to subdivide
2021-08-07 17:38:47.839 (   0.136s) [                ]vtkIntersectionPolyData:2410  WARN| No Intersection between objects
2021-08-07 17:38:47.840 (   0.137s) [                ]vtkDistancePolyDataFilt:82     ERR| vtkDistancePolyDataFilter (000002DAAB083FE0): No points/cells to operate on
ERROR:root:No points/cells to operate on
2021-08-07 17:38:47.840 (   0.138s) [                ]vtkDistancePolyDataFilt:82     ERR| vtkDistancePolyDataFilter (000002DAAB083FE0): No points/cells to operate on
ERROR:root:No points/cells to operate on
Traceback (most recent call last):
  File "C:\Users\user01\pyvista\booltest.py", line 32, in <module>
    p.add_mesh(union,  opacity=0.5, show_edges=True, color=True)
  File "C:\Users\user01\AppData\Local\Programs\Python\Python39\lib\site-packages\pyvista\plotting\plotting.py", line 1480, in add_mesh
    raise ValueError('Empty meshes cannot be plotted. Input mesh has zero points.')
ValueError: Empty meshes cannot be plotted. Input mesh has zero points.
PS C:\Users\user01\pyvista>

ブール演算：検証① → 失敗

ブール演算の前準備として、2つのオブジェクトを重なるように配置する

image.png

import pyvista as pv
pv.rcParams['transparent_background'] = True

obj0 = pv.Cube(
        center=(0.0, 0.0, 0.0), 
        x_length=1.0, 
        y_length=0.1, 
        z_length=1.0, 
        bounds=None
    )
obj2 = pv.Cylinder(
        center=(0.0, -0.05, 0.0), 
        direction=(0.0, 1.0, 0.0),
        radius=0.4, 
        height=0.4
    )

plotter = pv.Plotter(off_screen=False, window_size=(400,400))
plotter.camera.position    = (6.0, 6.0, 6.0)

plotter.add_mesh(obj0 ,color="FFFFFF", show_edges=True)
plotter.add_mesh(obj2 ,color="red", show_edges=True)

plotter.show()

これをブール演算するとエラー発生　※原因調査中※

エラーになる
import pyvista as pv
pv.rcParams['transparent_background'] = True

obj0 = pv.Cube(
        center=(0.0, 0.0, 0.0), 
        x_length=1.0, 
        y_length=0.1, 
        z_length=1.0, 
        bounds=None
    )

obj2 = pv.Cylinder(
        center=(0.0, -0.05, 0.0), 
        direction=(0.0, 1.0, 0.0),
        radius=0.4, 
        height=0.4
    )

union = obj2.boolean_union(obj0)

plotter = pv.Plotter(off_screen=False, window_size=(400,400))
plotter.camera.position    = (6.0, 6.0, 6.0)
plotter.add_mesh(union ,color="FFFFFF", show_edges=True)
plotter.show()

PS C:\Users\user01\python\pyvista> python .\test2.py
2021-08-08 06:29:41.575 (   0.138s) [                ]    vtkPointLocator.cxx:845    ERR| vtkPointLocator (000002BD6BE50CB0): No points to subdivide
ERROR:root:No points to subdivide
2021-08-08 06:29:41.577 (   0.139s) [                ]vtkIntersectionPolyData:2410  WARN| No Intersection between objects
2021-08-08 06:29:41.577 (   0.139s) [                ]vtkDistancePolyDataFilt:82     ERR| vtkDistancePolyDataFilter (000002BD5AD8F060): No points/cells to operate on
ERROR:root:No points/cells to operate on
2021-08-08 06:29:41.578 (   0.140s) [                ]vtkDistancePolyDataFilt:82     ERR| vtkDistancePolyDataFilter (000002BD5AD8F060): No points/cells to operate on
ERROR:root:No points/cells to operate on
Traceback (most recent call last):
  File "C:\Users\user01\python\pyvista\test2.py", line 25, in <module>
    plotter.add_mesh(union ,color="FFFFFF", show_edges=True)
  File "C:\Users\zgw42\AppData\Local\Programs\Python\Python39\lib\site-packages\pyvista\plotting\plotting.py", line 1480, in add_mesh
    raise ValueError('Empty meshes cannot be plotted. Input mesh has zero points.')
ValueError: Empty meshes cannot be plotted. Input mesh has zero points.
PS C:\Users\user01\python\pyvista>

（エラー対策わかったら追記します）

穴形状のオブジェクトを作ってみる

PyVistaの習得できた範囲で穴形状のオブジェクトを作ってみます。ブール演算は理解できてないので、壁に穴が空いた表現は、透過画像で代用します。中央に透過率100%の円がある画像を用意します。

image.png

実行結果

image.png

import pyvista as pv

pv.rcParams['transparent_background'] = True
targetImage = [ "image0.png" , "image1.png","image2.png" ]
tex = pv.numpy_to_texture(targetImage[2])

obj0 = pv.Plane(
        center=(0, 0, 0),
        direction=(0, 1, 0),
        i_size=1,
        j_size=1,
        i_resolution=20,
        j_resolution=20
    )
obj1 = pv.CylinderStructured(
        center=(0.0, -0.51, 0.0), 
        direction=(0.0, 1.0, 0.0), 
        radius=[0.3, 0.4], 
        height=1.0
    )

#plotter = pv.Plotter(off_screen=True, window_size=(400,400))
plotter = pv.Plotter(off_screen=False, window_size=(400,400))
plotter.camera.position    = (6.0, 6.0, 6.0)

plotter.add_mesh(obj0 ,color="FFFFFF", show_edges=False , texture=tex)
plotter.add_mesh(obj1 ,color="green", show_edges=True)

#plotter.screenshot('output.png')
plotter.show()

PyVistaまだまだわかってないです。調査はつづく

5
7
0

Register as a new user and use Qiita more conveniently

  1. You get articles that match your needs
  2. You can efficiently read back useful information
  3. You can use dark theme
What you can do with signing up
Sign upLogin
5
7

Delete article

Deleted articles cannot be recovered.

Draft of this article would be also deleted.

Are you sure you want to delete this article?