Python Tkinter - 在不创建新实例的情况下将形状绘制到屏幕
Python Tkinter - Draw Shape to Screen Without Creating New Instance
我打算创建一个基本程序，通过在单击鼠标时每帧创建椭圆来在屏幕上绘图。然而，随着程序运行一段时间，它开始变得非常不稳定，圆圈不再形成连贯的线条，这是因为代码 运行 速度不够快，无法处理精确的鼠标移动。
这是我的代码 -
import tkinter as tk
DRAW_HEIGHT = 560
DRAW_WIDTH = 560
PALETTE_HEIGHT = 40
def draw_palette(canvas):
canvas.create_rectangle(0, 0, DRAW_WIDTH, PALETTE_HEIGHT, fill = 'light grey', width= 0)
canvas.create_rectangle(DRAW_WIDTH/8, PALETTE_HEIGHT/5, 3*DRAW_WIDTH/8, 4*PALETTE_HEIGHT/5, fill = 'dark grey', width = 1)
canvas.create_rectangle(5*DRAW_WIDTH/8, PALETTE_HEIGHT/5, 7*DRAW_WIDTH/8, 4*PALETTE_HEIGHT/5, fill = 'dark grey',width = 1)
canvas.create_text(DRAW_WIDTH/4, PALETTE_HEIGHT/2, text = 'clear screen') #non-functional
class Brush():
def __init__(self,stroke_size,stroke_color):
self.size = stroke_size
self.color = stroke_color
self.mode = 'draw'
self.pos = (0,0)
self.clicked = False
def render(self,canvas):
if self.clicked:
canvas.create_oval( self.pos.x-self.size/2, self.pos.y-self.size/2,
self.pos.x+self.size/2, self.pos.y+self.size/2,
width = 0, fill = self.color )
def mouse_moved(self,event):
self.pos = event
def mouse_clicked(self,throwaway):
self.clicked = True
def mouse_released(self,throwaway):
self.clicked = False
#set up root window and canvas
root = tk.Tk()
root.geometry('{}x{}'.format(DRAW_WIDTH,DRAW_HEIGHT+PALETTE_HEIGHT))
c = tk.Canvas(root, width = DRAW_WIDTH, height = DRAW_HEIGHT + PALETTE_HEIGHT, bg = 'white')
c.pack()
b = Brush(40,'black')
#bind actions to functions
c.bind("<Button-1>",b.mouse_clicked)
c.bind("<ButtonRelease-1>",b.mouse_released)
c.bind("<Motion>",b.mouse_moved)
#main loop
while 1:
b.render(c)
draw_palette(c)
root.update()
我想我只是问是否有任何方法可以加快速度，但具体来说我想知道是否可以在不每次都使用 create_shape() 的情况下将形状绘制到屏幕上。
例如，
oval = c.create_oval()
while 1:
canvas.draw(oval)
我知道你可以用 canvas.move() 做类似的事情，但我找不到适合我情况的东西。
我不明白为什么你创建循环 while 1 和 运行 render() 和 draw_palette() 数百次，即使你不需要它。
我在 mouse_moved() 中画了新的圆并使用 root.mainloop() 并且它 运行 好多了并且创建了更平滑的线条。可能如果我从以前的地方画线到现在的地方，或者用一些步骤画许多椭圆，那么我会得到更好的线
编辑： 我在 mouse_click() 中画了第一个椭圆，所以即使我只点击而不移动，我也能看到第一个椭圆。
import tkinter as tk
# --- constanst ---
DRAW_HEIGHT = 560
DRAW_WIDTH = 560
PALETTE_HEIGHT = 40
# --- classes ---
class Brush():
def __init__(self,stroke_size,stroke_color):
self.size = stroke_size
self.color = stroke_color
self.mode = 'draw'
self.pos = (0,0)
self.clicked = False
def draw(self):
s = self.size/2
c.create_oval(
self.pos.x-s, self.pos.y-s,
self.pos.x+s, self.pos.y+s,
width=0, fill=self.color
)
def mouse_moved(self, event):
if self.clicked:
self.pos = event
self.draw()
def mouse_clicked(self, event):
self.clicked = True
self.pos = event
self.draw()
def mouse_released(self, event):
self.clicked = False
# --- functions ---
def draw_palette(canvas):
canvas.create_rectangle(0, 0, DRAW_WIDTH, PALETTE_HEIGHT, fill='light grey', width=0)
canvas.create_rectangle(DRAW_WIDTH/8, PALETTE_HEIGHT/5, 3*DRAW_WIDTH/8, 4*PALETTE_HEIGHT/5, fill='dark grey', width=1)
canvas.create_rectangle(5*DRAW_WIDTH/8, PALETTE_HEIGHT/5, 7*DRAW_WIDTH/8, 4*PALETTE_HEIGHT/5, fill='dark grey', width=1)
canvas.create_text(DRAW_WIDTH/4, PALETTE_HEIGHT/2, text='clear screen') #non-functional
# --- main ---
#set up root window and canvas
root = tk.Tk()
root.geometry('{}x{}'.format(DRAW_WIDTH, DRAW_HEIGHT+PALETTE_HEIGHT))
c = tk.Canvas(root, width=DRAW_WIDTH, height=DRAW_HEIGHT+PALETTE_HEIGHT, bg='white')
c.pack()
b = Brush(40, 'black')
#bind actions to functions
c.bind("<Button-1>", b.mouse_clicked)
c.bind("<ButtonRelease-1>", b.mouse_released)
c.bind("<Motion>", b.mouse_moved)
draw_palette(c)
root.mainloop()
编辑：
我添加了一个功能，如果前一个位置和当前位置之间的距离太大并且有间隙，则添加椭圆。现在即使鼠标快速移动线条也很流畅
import tkinter as tk
# --- constanst ---
DRAW_HEIGHT = 560
DRAW_WIDTH = 560
PALETTE_HEIGHT = 40
# --- classes ---
class Brush():
def __init__(self,stroke_size,stroke_color):
self.size = stroke_size
self.color = stroke_color
self.mode = 'draw'
self.pos = None
self.prev = None
self.clicked = False
def draw_oval(self, x, y):
r = self.size/2 # radius
c.create_oval(x-r, y-r, x+r, y+r, width=0, fill=self.color)
def draw(self):
if self.pos:
self.draw_oval(self.pos.x, self.pos.y)
if self.prev:
# calculate distance between ovals
dx = self.pos.x - self.prev.x
dy = self.pos.y - self.prev.y
max_diff = max(abs(dx), abs(dy))
# add ovals if distance bigger then some size of oval (tested with //4, //8, //6, //5)
if max_diff > (self.size//6):
# how many ovals to add
parts = max_diff//(self.size//6)
# distance between ovals
step_x = dx/parts
step_y = dy/parts
# add ovals except first which is already on canvas
for i in range(1, parts):
x = self.pos.x - i*step_x
y = self.pos.y - i*step_y
self.draw_oval(x, y)
def mouse_moved(self, event):
if self.clicked:
self.prev = self.pos
self.pos = event
self.draw()
def mouse_clicked(self, event):
self.clicked = True
self.prev = None
self.pos = event
self.draw()
def mouse_released(self, event):
self.clicked = False
self.prev = None
self.pos = None
# --- functions ---
def draw_palette(canvas):
canvas.create_rectangle(0, 0, DRAW_WIDTH, PALETTE_HEIGHT, fill='light grey', width=0)
canvas.create_rectangle(DRAW_WIDTH/8, PALETTE_HEIGHT/5, 3*DRAW_WIDTH/8, 4*PALETTE_HEIGHT/5, fill='dark grey', width=1)
canvas.create_rectangle(5*DRAW_WIDTH/8, PALETTE_HEIGHT/5, 7*DRAW_WIDTH/8, 4*PALETTE_HEIGHT/5, fill='dark grey', width=1)
canvas.create_text(DRAW_WIDTH/4, PALETTE_HEIGHT/2, text='clear screen') #non-functional
# --- main ---
#set up root window and canvas
root = tk.Tk()
root.geometry('{}x{}'.format(DRAW_WIDTH, DRAW_HEIGHT+PALETTE_HEIGHT))
c = tk.Canvas(root, width=DRAW_WIDTH, height=DRAW_HEIGHT+PALETTE_HEIGHT, bg='white')
c.pack()
b = Brush(40, 'black')
#bind actions to functions
c.bind("<Button-1>", b.mouse_clicked)
c.bind("<ButtonRelease-1>", b.mouse_released)
c.bind("<Motion>", b.mouse_moved)
draw_palette(c)
root.mainloop()
我打算创建一个基本程序，通过在单击鼠标时每帧创建椭圆来在屏幕上绘图。然而，随着程序运行一段时间，它开始变得非常不稳定，圆圈不再形成连贯的线条，这是因为代码 运行 速度不够快，无法处理精确的鼠标移动。
这是我的代码 -
import tkinter as tk
DRAW_HEIGHT = 560
DRAW_WIDTH = 560
PALETTE_HEIGHT = 40
def draw_palette(canvas):
canvas.create_rectangle(0, 0, DRAW_WIDTH, PALETTE_HEIGHT, fill = 'light grey', width= 0)
canvas.create_rectangle(DRAW_WIDTH/8, PALETTE_HEIGHT/5, 3*DRAW_WIDTH/8, 4*PALETTE_HEIGHT/5, fill = 'dark grey', width = 1)
canvas.create_rectangle(5*DRAW_WIDTH/8, PALETTE_HEIGHT/5, 7*DRAW_WIDTH/8, 4*PALETTE_HEIGHT/5, fill = 'dark grey',width = 1)
canvas.create_text(DRAW_WIDTH/4, PALETTE_HEIGHT/2, text = 'clear screen') #non-functional
class Brush():
def __init__(self,stroke_size,stroke_color):
self.size = stroke_size
self.color = stroke_color
self.mode = 'draw'
self.pos = (0,0)
self.clicked = False
def render(self,canvas):
if self.clicked:
canvas.create_oval( self.pos.x-self.size/2, self.pos.y-self.size/2,
self.pos.x+self.size/2, self.pos.y+self.size/2,
width = 0, fill = self.color )
def mouse_moved(self,event):
self.pos = event
def mouse_clicked(self,throwaway):
self.clicked = True
def mouse_released(self,throwaway):
self.clicked = False
#set up root window and canvas
root = tk.Tk()
root.geometry('{}x{}'.format(DRAW_WIDTH,DRAW_HEIGHT+PALETTE_HEIGHT))
c = tk.Canvas(root, width = DRAW_WIDTH, height = DRAW_HEIGHT + PALETTE_HEIGHT, bg = 'white')
c.pack()
b = Brush(40,'black')
#bind actions to functions
c.bind("<Button-1>",b.mouse_clicked)
c.bind("<ButtonRelease-1>",b.mouse_released)
c.bind("<Motion>",b.mouse_moved)
#main loop
while 1:
b.render(c)
draw_palette(c)
root.update()
我想我只是问是否有任何方法可以加快速度，但具体来说我想知道是否可以在不每次都使用 create_shape() 的情况下将形状绘制到屏幕上。
例如，
oval = c.create_oval()
while 1:
canvas.draw(oval)
我知道你可以用 canvas.move() 做类似的事情，但我找不到适合我情况的东西。
我不明白为什么你创建循环 while 1 和 运行 render() 和 draw_palette() 数百次，即使你不需要它。
我在 mouse_moved() 中画了新的圆并使用 root.mainloop() 并且它 运行 好多了并且创建了更平滑的线条。可能如果我从以前的地方画线到现在的地方，或者用一些步骤画许多椭圆，那么我会得到更好的线
编辑： 我在 mouse_click() 中画了第一个椭圆，所以即使我只点击而不移动，我也能看到第一个椭圆。
import tkinter as tk
# --- constanst ---
DRAW_HEIGHT = 560
DRAW_WIDTH = 560
PALETTE_HEIGHT = 40
# --- classes ---
class Brush():
def __init__(self,stroke_size,stroke_color):
self.size = stroke_size
self.color = stroke_color
self.mode = 'draw'
self.pos = (0,0)
self.clicked = False
def draw(self):
s = self.size/2
c.create_oval(
self.pos.x-s, self.pos.y-s,
self.pos.x+s, self.pos.y+s,
width=0, fill=self.color
)
def mouse_moved(self, event):
if self.clicked:
self.pos = event
self.draw()
def mouse_clicked(self, event):
self.clicked = True
self.pos = event
self.draw()
def mouse_released(self, event):
self.clicked = False
# --- functions ---
def draw_palette(canvas):
canvas.create_rectangle(0, 0, DRAW_WIDTH, PALETTE_HEIGHT, fill='light grey', width=0)
canvas.create_rectangle(DRAW_WIDTH/8, PALETTE_HEIGHT/5, 3*DRAW_WIDTH/8, 4*PALETTE_HEIGHT/5, fill='dark grey', width=1)
canvas.create_rectangle(5*DRAW_WIDTH/8, PALETTE_HEIGHT/5, 7*DRAW_WIDTH/8, 4*PALETTE_HEIGHT/5, fill='dark grey', width=1)
canvas.create_text(DRAW_WIDTH/4, PALETTE_HEIGHT/2, text='clear screen') #non-functional
# --- main ---
#set up root window and canvas
root = tk.Tk()
root.geometry('{}x{}'.format(DRAW_WIDTH, DRAW_HEIGHT+PALETTE_HEIGHT))
c = tk.Canvas(root, width=DRAW_WIDTH, height=DRAW_HEIGHT+PALETTE_HEIGHT, bg='white')
c.pack()
b = Brush(40, 'black')
#bind actions to functions
c.bind("<Button-1>", b.mouse_clicked)
c.bind("<ButtonRelease-1>", b.mouse_released)
c.bind("<Motion>", b.mouse_moved)
draw_palette(c)
root.mainloop()
编辑：
我添加了一个功能，如果前一个位置和当前位置之间的距离太大并且有间隙，则添加椭圆。现在即使鼠标快速移动线条也很流畅
import tkinter as tk
# --- constanst ---
DRAW_HEIGHT = 560
DRAW_WIDTH = 560
PALETTE_HEIGHT = 40
# --- classes ---
class Brush():
def __init__(self,stroke_size,stroke_color):
self.size = stroke_size
self.color = stroke_color
self.mode = 'draw'
self.pos = None
self.prev = None
self.clicked = False
def draw_oval(self, x, y):
r = self.size/2 # radius
c.create_oval(x-r, y-r, x+r, y+r, width=0, fill=self.color)
def draw(self):
if self.pos:
self.draw_oval(self.pos.x, self.pos.y)
if self.prev:
# calculate distance between ovals
dx = self.pos.x - self.prev.x
dy = self.pos.y - self.prev.y
max_diff = max(abs(dx), abs(dy))
# add ovals if distance bigger then some size of oval (tested with //4, //8, //6, //5)
if max_diff > (self.size//6):
# how many ovals to add
parts = max_diff//(self.size//6)
# distance between ovals
step_x = dx/parts
step_y = dy/parts
# add ovals except first which is already on canvas
for i in range(1, parts):
x = self.pos.x - i*step_x
y = self.pos.y - i*step_y
self.draw_oval(x, y)
def mouse_moved(self, event):
if self.clicked:
self.prev = self.pos
self.pos = event
self.draw()
def mouse_clicked(self, event):
self.clicked = True
self.prev = None
self.pos = event
self.draw()
def mouse_released(self, event):
self.clicked = False
self.prev = None
self.pos = None
# --- functions ---
def draw_palette(canvas):
canvas.create_rectangle(0, 0, DRAW_WIDTH, PALETTE_HEIGHT, fill='light grey', width=0)
canvas.create_rectangle(DRAW_WIDTH/8, PALETTE_HEIGHT/5, 3*DRAW_WIDTH/8, 4*PALETTE_HEIGHT/5, fill='dark grey', width=1)
canvas.create_rectangle(5*DRAW_WIDTH/8, PALETTE_HEIGHT/5, 7*DRAW_WIDTH/8, 4*PALETTE_HEIGHT/5, fill='dark grey', width=1)
canvas.create_text(DRAW_WIDTH/4, PALETTE_HEIGHT/2, text='clear screen') #non-functional
# --- main ---
#set up root window and canvas
root = tk.Tk()
root.geometry('{}x{}'.format(DRAW_WIDTH, DRAW_HEIGHT+PALETTE_HEIGHT))
c = tk.Canvas(root, width=DRAW_WIDTH, height=DRAW_HEIGHT+PALETTE_HEIGHT, bg='white')
c.pack()
b = Brush(40, 'black')
#bind actions to functions
c.bind("<Button-1>", b.mouse_clicked)
c.bind("<ButtonRelease-1>", b.mouse_released)
c.bind("<Motion>", b.mouse_moved)
draw_palette(c)
root.mainloop()