当然，您需要将功能添加到中
PolygonInteractor。但是不要让它自己绘制任何东西。然后在类中添加新行，
self.line2这将是要更新的行。
最后，让全班同学也为您画一条新线。并使用插值函数的结果更新它。
为了方便起见，您可以将“多边形（
self.poly）”设置为不可见，也可以从中删除该线，
self.line并且仅显示点可能有意义。
import numpy as npfrom scipy.interpolate import interp1dfrom matplotlib.lines import Line2Dfrom matplotlib.artist import Artistfrom matplotlib.mlab import dist_point_to_segmentclass PolygonInteractor(object): """ A polygon editor. https://matplotlib.org/gallery/event_handling/poly_editor.html Key-bindings 't' toggle vertex markers on and off. When vertex markers are on, you can move them, delete them 'd' delete the vertex under point 'i' insert a vertex at point. You must be within epsilon of the line connecting two existing vertices """ showverts = True epsilon = 5 # max pixel distance to count as a vertex hit def __init__(self, ax, poly, visible=False): if poly.figure is None: raise RuntimeError('You must first add the polygon to a figure ' 'or canvas before defining the interactor') self.ax = ax canvas = poly.figure.canvas self.poly = poly self.poly.set_visible(visible) x, y = zip(*self.poly.xy) self.line = Line2D(x, y, ls="", marker='o', markerfacecolor='r', animated=True) self.ax.add_line(self.line) self.cid = self.poly.add_callback(self.poly_changed) self._ind = None # the active vert canvas.mpl_connect('draw_event', self.draw_callback) canvas.mpl_connect('button_press_event', self.button_press_callback) canvas.mpl_connect('key_press_event', self.key_press_callback) canvas.mpl_connect('button_release_event', self.button_release_callback) canvas.mpl_connect('motion_notify_event', self.motion_notify_callback) self.canvas = canvas x,y = self.interpolate() self.line2 = Line2D(x, y, animated=True) self.ax.add_line(self.line2) def interpolate(self): x, y = self.poly.xy[:].T i = np.arange(len(x)) interp_i = np.linspace(0, i.max(), 100 * i.max()) xi = interp1d(i, x, kind='cubic')(interp_i) yi = interp1d(i, y, kind='cubic')(interp_i) return xi,yi def draw_callback(self, event): self.background = self.canvas.copy_from_bbox(self.ax.bbox) self.ax.draw_artist(self.poly) self.ax.draw_artist(self.line) self.ax.draw_artist(self.line2) # do not need to blit here, this will fire before the screen is # updated def poly_changed(self, poly): 'this method is called whenever the polygon object is called' # only copy the artist props to the line (except visibility) vis = self.line.get_visible() Artist.update_from(self.line, poly) self.line.set_visible(vis) # don't use the poly visibility state def get_ind_under_point(self, event): 'get the index of the vertex under point if within epsilon tolerance' # display coords xy = np.asarray(self.poly.xy) xyt = self.poly.get_transform().transform(xy) xt, yt = xyt[:, 0], xyt[:, 1] d = np.hypot(xt - event.x, yt - event.y) indseq, = np.nonzero(d == d.min()) ind = indseq[0] if d[ind] >= self.epsilon: ind = None return ind def button_press_callback(self, event): 'whenever a mouse button is pressed' if not self.showverts: return if event.inaxes is None: return if event.button != 1: return self._ind = self.get_ind_under_point(event) def button_release_callback(self, event): 'whenever a mouse button is released' if not self.showverts: return if event.button != 1: return self._ind = None def key_press_callback(self, event): 'whenever a key is pressed' if not event.inaxes: return if event.key == 't': self.showverts = not self.showverts self.line.set_visible(self.showverts) if not self.showverts: self._ind = None elif event.key == 'd': ind = self.get_ind_under_point(event) if ind is not None: self.poly.xy = np.delete(self.poly.xy, ind, axis=0) self.line.set_data(zip(*self.poly.xy)) elif event.key == 'i': xys = self.poly.get_transform().transform(self.poly.xy) p = event.x, event.y # display coords for i in range(len(xys) - 1): s0 = xys[i] s1 = xys[i + 1] d = dist_point_to_segment(p, s0, s1) if d <= self.epsilon: self.poly.xy = np.insert( self.poly.xy, i+1, [event.xdata, event.ydata], axis=0) self.line.set_data(zip(*self.poly.xy)) break if self.line.stale: self.canvas.draw_idle() def motion_notify_callback(self, event): 'on mouse movement' if not self.showverts: return if self._ind is None: return if event.inaxes is None: return if event.button != 1: return x, y = event.xdata, event.ydata self.poly.xy[self._ind] = x, y if self._ind == 0: self.poly.xy[-1] = x, y elif self._ind == len(self.poly.xy) - 1: self.poly.xy[0] = x, y self.line.set_data(zip(*self.poly.xy)) x,y = self.interpolate() self.line2.set_data(x,y) self.canvas.restore_region(self.background) self.ax.draw_artist(self.poly) self.ax.draw_artist(self.line) self.ax.draw_artist(self.line2) self.canvas.blit(self.ax.bbox)if __name__ == '__main__': import matplotlib.pyplot as plt from matplotlib.patches import Polygon #theta = np.arange(0, 2*np.pi, 0.1) #r = 1.5 #xs = r*np.cos(theta) #ys = r*np.sin(theta) xs = (921, 951, 993, 1035, 1065, 1045, 993, 945) ys = (1181, 1230, 1243, 1230, 1181, 1130, 1130, 1130) poly = Polygon(list(zip(xs, ys)), animated=True) fig, ax = plt.subplots() ax.add_patch(poly) p = PolygonInteractor(ax, poly, visible=False) ax.set_title('Click and drag a point to move it') ax.set_xlim((800, 1300)) ax.set_ylim((1000, 1300)) plt.show()请注意，此处创建的曲线不是真正的循环。它有一个起点，曲线并不真正平滑。可以通过使用贝塞尔曲线的真循环集来避免这种情况，如使用matplotlib创建随机形状/轮廓所示。
