如何用PIL绘制等宽垂直线与斜线？已有水平线实现代码

问题背景 #

已通过PIL实现等宽水平线的绘制，现在需要完成等宽垂直线与斜线的绘制。

原水平线实现代码 #

from PIL import Image, ImageDraw
import random

im = Image.new('RGB', (1000, 1000), (255, 255, 255))
draw = ImageDraw.Draw(im)
colors = [(255,0,0), (255,255,0), (255,0,255)]
random.shuffle(colors)
length = len(colors)
amount = 1000 / length

x1 = 0
y1 = 0
x2 = 0
y2 = 1000
for color in colors:
    shape = [(x1 + amount, y1 // 2), (x2 + amount, y2 // 2)]
    draw.line(shape, fill=color, width=int(amount))
    x1 += amount
    x2 += amount

im.save('horizontal_lines.png')

等宽垂直线实现代码 #

垂直线的绘制逻辑和水平线对称，只需调整线段坐标为垂直方向，通过宽度参数控制色块宽度：

from PIL import Image, ImageDraw
import random

im = Image.new('RGB', (1000, 1000), (255, 255, 255))
draw = ImageDraw.Draw(im)
colors = [(255,0,0), (255,255,0), (255,0,255)]
random.shuffle(colors)
length = len(colors)
amount = 1000 / length

y1 = 0
x1 = 0
y2 = 0
x2 = 1000
for color in colors:
    # 垂直线段垂直贯穿画布，沿水平方向分布
    shape = [(x1 // 2, y1 + amount), (x2 // 2, y2 + amount)]
    draw.line(shape, fill=color, width=int(amount))
    y1 += amount
    y2 += amount

im.save('vertical_lines.png')

等宽斜线实现代码 #

斜线若用line的width参数很难保证视觉等宽，建议绘制闭合多边形填充斜向区域，以45度斜向分割为例：

from PIL import Image, ImageDraw
import random
import math

im = Image.new('RGB', (1000, 1000), (255, 255, 255))
draw = ImageDraw.Draw(im)
colors = [(255,0,0), (255,255,0), (255,0,255)]
random.shuffle(colors)
length = len(colors)

# 按画布对角线长度计算每个斜向区域的宽度
diagonal_length = math.hypot(1000, 1000)
amount = diagonal_length / length
# 45度斜线的方向向量比例
dx = 1000 / diagonal_length
dy = 1000 / diagonal_length

current_offset = 0
for color in colors:
    # 构建斜向区域的多边形顶点
    polygon = [
        (current_offset * dx, 0),
        (1000, 1000 - current_offset * dy),
        (1000 - (current_offset + amount) * dx, 1000),
        (0, (current_offset + amount) * dy)
    ]
    draw.polygon(polygon, fill=color)
    current_offset += amount

im.save('diagonal_lines.png')

补充说明 #

• 垂直线与水平线逻辑对称，仅调整了线段的延伸方向；
• 斜线采用多边形填充，能精准保证每个斜向区域的视觉宽度一致，避免单纯画线带来的宽度偏差。

内容的提问来源于stack exchange，提问作者Mashu