Python中的魔杖 push() 和 pop()

我们可以使用 ImageMagick 的内部图形上下文堆栈来管理 Wand 中的不同样式和操作。上下文堆栈共有四个推送函数。

• 推（）
• push_clip_path()
• push_defs()
• push_pattern()

push()函数用于增长上下文堆栈，而 pop() 是另一个函数，用于将堆栈恢复到先前的推送。

Syntax : 
 

Parameters : No parameters for push() as well as for pop() function

示例 #1：

Python3

# for push()
wand.drawing.push()

# for pop()
wand.drawing.pop()

Python3

from wand.image import Image
from wand.drawing import Drawing
from wand.color import Color
 
with Drawing() as ctx:
    ctx.fill_color = Color('RED')
    ctx.stroke_color = Color('BLACK')
    ctx.push()
 
    ctx.circle((50, 50), (25, 25))
    ctx.pop()
 
    ctx.fill_color = Color('YELLOW')
    ctx.stroke_color = Color('GREEN')
    ctx.push()
 
    ctx.circle((150, 150), (125, 125))
    ctx.pop()
 
    with Image(width = 200, height = 200, background = Color('lightgreen')) as image:
        ctx(image)
        image.save(filename = "push.png")

输出：

示例 #2：

Python3

from wand.color import Color
from wand.image import Image
from wand.drawing import Drawing
from wand.compat import nested
from math import cos, pi, sin
 
with nested(Color('lightblue'),
            Color('transparent'),
            Drawing()) as (bg, fg, draw):
    draw.stroke_width = 3
    draw.fill_color = fg
 
    for degree in range(0, 360, 15):
        draw.push()  # Grow stack
        draw.stroke_color = Color('hsl({0}%, 100 %, 50 %)'.format(degree * 100 / 360))
        t = degree / 180.0 * pi
        x = 35 * cos(t) + 50
        y = 35 * sin(t) + 50
        draw.line((50, 50), (x, y))
        draw.pop()  # Restore stack
 
    with Image(width = 100, height = 100, background = Color('green')) as img:
        draw(img)
        img.save(filename = "pushpop.png")

输出：