如果你只需要知道点击了哪条曲线,那并不是很困难。您需要创建一个 line_picker() 来检查鼠标位置是否足够接近曲线。
line_picker() 需要计算点和线段之间的距离,这有点困难,我通过使用曲线的线性插值来解决这个问题。
这是代码,我将曲线插值2000个点,如果鼠标到曲线的位置小于5像素,则选择曲线。
import matplotlib as mpl
from mpl_toolkits.mplot3d import Axes3D
import numpy as np
import matplotlib.pyplot as plt
def line_picker(line, me):
if me.xdata is None: return False, dict()
x, y = me.x, me.y
xdata, ydata = line.axes.transData.transform(np.array(line.get_data()).T).T
index = np.arange(len(xdata))
index2 = np.linspace(0, index[-1], 2000)
xdata2 = np.interp(index2, index, xdata)
ydata2 = np.interp(index2, index, ydata)
d = np.sqrt((xdata2-x)**2. + (ydata2-y)**2.)
if np.min(d) < 5:
return True, {}
else:
return False, {}
mpl.rcParams['legend.fontsize'] = 10
fig = plt.figure()
ax = fig.gca(projection='3d')
theta = np.linspace(-4 * np.pi, 4 * np.pi, 100)
z = np.linspace(-2, 2, 100)
r = z**2 + 1
x = r * np.sin(theta)
y = r * np.cos(theta)
line1 = ax.plot(x, y, z, label='parametric curve', picker=line_picker)[0]
t = np.linspace(-1, 1, 100)
x = 4*np.sin(10*t)
y = 4*np.cos(10*t)
z = t**2*5-3
line2 = ax.plot(x, y, z, label="second", picker=line_picker)[0]
ax.legend()
def onpick(event):
print [line1, line2].index(event.artist)
fig.canvas.mpl_connect('pick_event', onpick)
plt.show()