Python：获取两个3D点之间的所有坐标或绘制3D线

Question

I have the following problem. I have 3D point coordinates and I want to conenct them in an array or "draw a line" like you can do it in 2D with skimage( http://scikit-image.org/docs/0.13.x/api/skimage.draw.html#skimage.draw.line ). The optimal case would be if i could directly draw a cylinder with a radius in an array and give different radius different values like rings arround the line.(wrinkles could be a problem here) . There have been approaches to do that but they are not the right thing i think like here:

"Draw" a 3d line into an array

With the two approaches of @Paul Panzer ( Fastest way to get all the points between two (X,Y) coordinates in python ) you get all coordinates between two 2D Points, but how would it look like in 3D, esspecially the second approach which is faster?:

import numpy as np
from timeit import timeit

def connect(ends):
    d0, d1 = np.abs(np.diff(ends, axis=0))[0]
    if d0 > d1: 
        return np.c_[np.linspace(ends[0, 0], ends[1, 0], d0+1, dtype=np.int32),
                     np.linspace(ends[0, 1]+0.5, ends[1, 1]+0.5, d0+1, dtype=np.int32)]
    else:
        return np.c_[np.linspace(ends[0, 0]+0.5, ends[1, 0]+0.5, d1+1, dtype=np.int32),
                     np.linspace(ends[0, 1], ends[1, 1], d1+1, dtype=np.int32)]


def connect2(ends):
    d0, d1 = np.diff(ends, axis=0)[0]
    if np.abs(d0) > np.abs(d1): 
        return np.c_[np.arange(ends[0, 0], ends[1,0] + np.sign(d0), np.sign(d0), dtype=np.int32),
                     np.arange(ends[0, 1] * np.abs(d0) + np.abs(d0)//2,
                               ends[0, 1] * np.abs(d0) + np.abs(d0)//2 + (np.abs(d0)+1) * d1, d1, dtype=np.int32) // np.abs(d0)]
    else:
        return np.c_[np.arange(ends[0, 0] * np.abs(d1) + np.abs(d1)//2,
                               ends[0, 0] * np.abs(d1) + np.abs(d1)//2 + (np.abs(d1)+1) * d0, d0, dtype=np.int32) // np.abs(d1),
                     np.arange(ends[0, 1], ends[1,1] + np.sign(d1), np.sign(d1), dtype=np.int32)]


ends = np.array([[ 1520, -1140],
                 [ 1412,  -973]])

Answer 1

Since you tagged the question 'vtk', I assume you can use it in your code. In that case, I think vtkTubeFilter does exactly what you are looking for - you create a vtkPolyData with all your line segments (you have your endpoints for that) and for each segment, the filter generates a cylinder. You can also specify different radius for each segment as you wanted: call SetVaryRadiusToVaryRadiusByScalar() on the filter to turn it on and provide the array with radii as scalar data.

You can find a code example that does all that (and more) here: https://www.vtk.org/Wiki/VTK/Examples/Cxx/VisualizationAlgorithms/TubesWithVaryingRadiusAndColors