当然可以！你需要的是blitting。如果你不是在编写GUI程序，可以使用matplotlib.animation简化其中的一些部分，但如果你想要交互式显示，就需要直接处理它。
在matplotlib中，你需要使用fig.canvas.copy_from_bbox组合，然后交替调用fig.canvas.restore_region(background)，ax.draw_artist(what_you_want_to_draw)和fig.canvas.blit：
background = fig.canvas.copy_from_bbox(ax.bbox)
for x, y in user_interactions:
fig.canvas.restore_region(background)
points.append([x, y])
scatter.set_offsets(points)
ax.draw_artist(scatter)
fig.canvas.blit(ax.bbox)
简单的位块传输示例：添加点
如果你只是要添加点，那么你可以跳过保存和恢复背景。但是，这样做会导致抗锯齿点被反复绘制在彼此之上，从而产生一些微妙的绘图变化。
无论如何，以下是你想要的最简单的示例。它仅涉及添加点，并跳过了保存和恢复背景：
import matplotlib.pyplot as plt
import numpy as np
def main():
fig, ax = plt.subplots()
ax.pcolormesh(np.random.random((100, 100)), cmap='gray')
ClickToDrawPoints(ax).show()
class ClickToDrawPoints(object):
def __init__(self, ax):
self.ax = ax
self.fig = ax.figure
self.xy = []
self.points = ax.scatter([], [], s=200, color='red', picker=20)
self.fig.canvas.mpl_connect('button_press_event', self.on_click)
def on_click(self, event):
if event.inaxes is None:
return
self.xy.append([event.xdata, event.ydata])
self.points.set_offsets(self.xy)
self.ax.draw_artist(self.points)
self.fig.canvas.blit(self.ax.bbox)
def show(self):
plt.show()
main()
有时候简单的东西过于简单
然而，假设我们想让右键单击删除一个点。
在这种情况下，我们需要能够恢复背景而不重新绘制它。
好的，一切都很好。我们将使用与我在答案开头提到的伪代码片段类似的东西。
但是，有一个注意事项：如果调整了图形大小，则需要更新背景。同样，如果交互式缩放/平移坐标轴，则需要更新背景。基本上，任何时候绘制图表都需要更新背景。
很快你就需要变得相当复杂。
更复杂：添加/拖动/删除点
这是一般示例的“脚手架”。这种方法有些低效，因为图会被画两次（例如平移将很慢）。有可能解决这个问题，但我会在另一个时间留下这些例子。
这实现了添加点、拖动点和删除点。要在交互式缩放/平移后添加/拖动点，请再次单击工具栏上的缩放/平移工具以禁用它们。
这是一个相当复杂的例子，但希望它能给人们一种构建交互式绘制/拖动/编辑/删除matplotlib艺术家的框架类型的感觉，而无需重新绘制整个图表。
import numpy as np
import matplotlib.pyplot as plt
class DrawDragPoints(object):
"""
Demonstrates a basic example of the "scaffolding" you need to efficiently
blit drawable/draggable/deleteable artists on top of a background.
"""
def __init__(self):
self.fig, self.ax = self.setup_axes()
self.xy = []
self.tolerance = 10
self._num_clicks = 0
self.points = self.ax.scatter([], [], s=200, color='red',
picker=self.tolerance, animated=True)
connect = self.fig.canvas.mpl_connect
connect('button_press_event', self.on_click)
self.draw_cid = connect('draw_event', self.grab_background)
def setup_axes(self):
"""Setup the figure/axes and plot any background artists."""
fig, ax = plt.subplots()
ax.pcolormesh(np.random.random((1000, 1000)), cmap='gray')
ax.set_title('Left click to add/drag a point\nRight-click to delete')
return fig, ax
def on_click(self, event):
"""Decide whether to add, delete, or drag a point."""
if self.fig.canvas.toolbar._active is not None:
return
contains, info = self.points.contains(event)
if contains:
i = info['ind'][0]
if event.button == 1:
self.start_drag(i)
elif event.button == 3:
self.delete_point(i)
else:
self.add_point(event)
def update(self):
"""Update the artist for any changes to self.xy."""
self.points.set_offsets(self.xy)
self.blit()
def add_point(self, event):
self.xy.append([event.xdata, event.ydata])
self.update()
def delete_point(self, i):
self.xy.pop(i)
self.update()
def start_drag(self, i):
"""Bind mouse motion to updating a particular point."""
self.drag_i = i
connect = self.fig.canvas.mpl_connect
cid1 = connect('motion_notify_event', self.drag_update)
cid2 = connect('button_release_event', self.end_drag)
self.drag_cids = [cid1, cid2]
def drag_update(self, event):
"""Update a point that's being moved interactively."""
self.xy[self.drag_i] = [event.xdata, event.ydata]
self.update()
def end_drag(self, event):
"""End the binding of mouse motion to a particular point."""
for cid in self.drag_cids:
self.fig.canvas.mpl_disconnect(cid)
def safe_draw(self):
"""Temporarily disconnect the draw_event callback to avoid recursion"""
canvas = self.fig.canvas
canvas.mpl_disconnect(self.draw_cid)
canvas.draw()
self.draw_cid = canvas.mpl_connect('draw_event', self.grab_background)
def grab_background(self, event=None):
"""
When the figure is resized, hide the points, draw everything,
and update the background.
"""
self.points.set_visible(False)
self.safe_draw()
self.background = self.fig.canvas.copy_from_bbox(self.fig.bbox)
self.points.set_visible(True)
self.blit()
def blit(self):
"""
Efficiently update the figure, without needing to redraw the
"background" artists.
"""
self.fig.canvas.restore_region(self.background)
self.ax.draw_artist(self.points)
self.fig.canvas.blit(self.fig.bbox)
def show(self):
plt.show()
DrawDragPoints().show()
