python画圆角矩形_Python图像库（PIL）绘图——带渐变的圆角矩形

这是一种非常野蛮的方法，但它能完成任务。生成渐变的代码是从here中借用的。from PIL import Image, ImageDraw

def channel(i, c, size, startFill, stopFill):

"""calculate the value of a single color channel for a single pixel"""

return startFill[c] + int((i * 1.0 / size) * (stopFill[c] - startFill[c]))

def color(i, size, startFill, stopFill):

"""calculate the RGB value of a single pixel"""

return tuple([channel(i, c, size, startFill, stopFill) for c in range(3)])

def round_corner(radius):

"""Draw a round corner"""

corner = Image.new('RGBA', (radius, radius), (0, 0, 0, 0))

draw = ImageDraw.Draw(corner)

draw.pieslice((0, 0, radius * 2, radius * 2), 180, 270, fill="blue")

return corner

def apply_grad_to_corner(corner, gradient, backwards = False, topBottom = Fals