Python更改渐变以对角开始
我有一个生成梯度的简单函数。我想将渐变方向更改为从左上角的对角线开始Python更改渐变以对角开始,python,python-imaging-library,python-3.4,pillow,Python,Python Imaging Library,Python 3.4,Pillow,我有一个生成梯度的简单函数。我想将渐变方向更改为从左上角的对角线开始 im = Image.new('RGB', (300, 300)) ld = im.load() # A map of rgb points in your distribution # [distance, (r, g, b)] # distance is percentage from left edge heatmap = [ [0.0, (0, 0, 0)], [1.00, (0.8, 0.0, 1
im = Image.new('RGB', (300, 300))
ld = im.load()
# A map of rgb points in your distribution
# [distance, (r, g, b)]
# distance is percentage from left edge
heatmap = [
[0.0, (0, 0, 0)],
[1.00, (0.8, 0.0, 1.0)],
]
def gaussian(x, a, b, c, d=0):
return a * math.exp(-(x - b) ** 2 / (2 * c ** 2)) + d
def pixel(x, width=100, map=[], spread=1):
width = float(width)
r = sum([gaussian(x, p[1][0], p[0] * width, width / (spread * len(map))) for p in map])
g = sum([gaussian(x, p[1][1], p[0] * width, width / (spread * len(map))) for p in map])
b = sum([gaussian(x, p[1][2], p[0] * width, width / (spread * len(map))) for p in map])
return min(1.0, r), min(1.0, g), min(1.0, b)
for x in range(im.size[0]):
r, g, b = pixel(x, width=300, map=heatmap)
r, g, b = [int(256 * v) for v in (r, g, b)]
for y in range(im.size[1]):
ld[x, y] = r, g, b
我发现我可以改变方向从上到下,从左到右,但不知道如何改变它的对角线
for y in range(im.size[1]):
ld[y, x] = r, g, b
给
给
使用当前的功能和方式是否可以实现这一点?您的
宽度应为300*300
然后用下面的循环替换您的循环应该可以工作
for y in range(im.size[1]-1):
r, g, b = pixel(y, width=300*300, map=heatmap)
r, g, b = [int(256 * v) for v in (r, g, b)]
for x_ in range(y+1):
ld[x_,y - x_] = r, g, b
for x in range(im.size[0]):
r, g, b = pixel(300+x, width=300*300, map=heatmap)
r, g, b = [int(256 * v) for v in (r, g, b)]
for y_ in range(im.size[1]):
ld[x - y_,y_] = r, g, b
未经测试,但类似的方法应该有效尝试以下方法:
for y in range(im.size[1]-1):
r, g, b = pixel(y, width=300*300, map=heatmap)
r, g, b = [int(256 * v) for v in (r, g, b)]
for x_ in range(y+1):
ld[x_,y - x_] = r, g, b
for x in range(im.size[0]):
r, g, b = pixel(300+x, width=300*300, map=heatmap)
r, g, b = [int(256 * v) for v in (r, g, b)]
for y_ in range(im.size[1]):
ld[x - y_,y_] = r, g, b
heatmap = [
[0.0, (0, 0, 0)],
[1.00, (0.8, 0.0, 1.0)],
]
# x y coordinates of starting point for gradient
start_x = 0
start_y = 0
for x in range(im.size[0]):
for y in range(im.size[1]):
# taxicab distance for linear gradient
dist = math.fabs(start_x - x) + math.fabs(start_y - y)
# for circular gradient
# dist = math.sqrt(math.pow(start_x - x,2) + math.pow(start_y - y,2))
start_rgb = heatmap[0][1]
end_rgb = heatmap[1][1]
dist = dist / (im.size[0] + im.size[1])
# for circular gradient
# dist = dist / (math.sqrt(math.pow(im.size[0],2) + math.pow(im.size[1],2))
r, g, b = map(lambda x,y: x+y, map(lambda a: a*dist, start_rgb), map(lambda b: b*dist, end_rgb))
r, g, b = [int(256 * v) for v in (r, g, b)]
ld[x, y] = r, g, b
我假设start_x
和start_y
位于图像的四个角之一。相应地调整start_x-x
和start_y-y
,如果它不是这样的话。您可能会发现第一个程序很有用。