我希望在python中的照片上创建对角渐变。

我能够创建垂直和水平淡入淡出，但是当组合在一起时，一个会覆盖另一个。我知道为什么，我只是不知道如何解决它。我意识到这里可能有很多没有意义的东西，对Python来说相对较新，只是试图弄清楚。预先感谢！

img = Image.open('Anacapa 011.tif')

img = img.copy()
img.putalpha(150)

width,height = img.size
pixels = img.load()

for y in range (int(0),int(height)):
    alpha = 150 - int((height*.50 - y)/height/.3 * 150)
    for x in range(width):
        pixels[x,y] = pixels[x,y][:3] + (alpha,)
for y in range(y,height):
    for x in range(width):
        pixels[x,y][:3] + (0,)

img1 = img.copy()

width1,height1 = img.size
pixels1 = img.load()

for x1 in range (int(0),int(width1)):
    alpha = 150 - int((x1 - width1*.4)/width1/.3 * 150)
    for y1 in range(height1):
        pixels1[x1,y1] = pixels1[x1,y1][:3] + (alpha,)
for x1 in range(x1,width1):
    for y1 in range(height1):
        pixels1[x1,y1][:3] + (0,)