python - 一旦超过特定宽度，就沿空白符断开字符串(Python)

我在一个基础图像上渲染文本。
一个核心要求是当字符的总宽度超过基础图像的宽度时，字符串将换行到下一行。我通过以下正确工作的片段来完成此任务：

base_width, base_height = base_img.size
font = ImageFont.truetype("/usr/share/fonts/truetype/dejavu/DejaVuSans.ttf", font_size)
line_width = 0
line_count = 1
lines = []
string = ""
for c in text:
    line_width += font.getsize(c)[0]
    string+=str(c)
    if line_width > base_width:
        lines.append(string)
        string = ""
        line_width = 0
        line_count += 1
if string:
    lines.append(string)

结果lines是通过分解原始字符串得到的子字符串列表。
现在我需要改进这个算法。
问题是它在单词中间断行。例如，字符串lorem ipsum可能以lines = ['lorem ip','sum']结束。相反，对我来说，理想的分手方式是更容易理解的。
换言之，我想在空白处划一条线，而不是中间的字。有人能给我举个例子说明我是如何做到这一点的吗？好像不能让我的头绕着它转。

最佳答案

下面是一个尝试，让您的代码在最少的更改和大量调试输出的情况下工作：

#!python3
#coding=utf-8
""" Line break demo 2 """

text = "lorem ipsum dolor sit amet blablah"

for wmax in [10,25,55,80,100,120]:

    print(wmax)

    base_width, base_height = (wmax,None)#base_img.size
    #font = ImageFont.truetype("/usr/share/fonts/truetype/dejavu/DejaVuSans.ttf", font_size)
    line_width = 0
    line_count = 1
    lines = []
    string = ""
    for c in text:
        line_width += 5#font.getsize(c)[0]
        string += c
        if line_width > base_width:

            print("text  ", text)
            print("string", string)

            s = string.rsplit(" ", 1)
            print("split ", s)

            string = s[0]
            lines.append(string)

            try:
                string = s[1]
                line_width = len(string) * 5
            except:
                string = ""
                line_width = 0

            print("lines ", lines)
            print("string", string)

            line_count += 1
            print()

    if string:
        lines.append(string)


    print(lines)
    print()

输出：

10
text   lorem ipsum dolor sit amet blablah
string lor
split  ['lor']
lines  ['lor']
string

text   lorem ipsum dolor sit amet blablah
string em
split  ['em', '']
lines  ['lor', 'em']
string

text   lorem ipsum dolor sit amet blablah
string ips
split  ['ips']
lines  ['lor', 'em', 'ips']
string

text   lorem ipsum dolor sit amet blablah
string um
split  ['um', '']
lines  ['lor', 'em', 'ips', 'um']
string

text   lorem ipsum dolor sit amet blablah
string dol
split  ['dol']
lines  ['lor', 'em', 'ips', 'um', 'dol']
string

text   lorem ipsum dolor sit amet blablah
string or
split  ['or', '']
lines  ['lor', 'em', 'ips', 'um', 'dol', 'or']
string

text   lorem ipsum dolor sit amet blablah
string sit
split  ['sit']
lines  ['lor', 'em', 'ips', 'um', 'dol', 'or', 'sit']
string

text   lorem ipsum dolor sit amet blablah
string  am
split  ['', 'am']
lines  ['lor', 'em', 'ips', 'um', 'dol', 'or', 'sit', '']
string am

text   lorem ipsum dolor sit amet blablah
string ame
split  ['ame']
lines  ['lor', 'em', 'ips', 'um', 'dol', 'or', 'sit', '', 'ame']
string

text   lorem ipsum dolor sit amet blablah
string t b
split  ['t', 'b']
lines  ['lor', 'em', 'ips', 'um', 'dol', 'or', 'sit', '', 'ame', 't']
string b

text   lorem ipsum dolor sit amet blablah
string bla
split  ['bla']
lines  ['lor', 'em', 'ips', 'um', 'dol', 'or', 'sit', '', 'ame', 't', 'bla']
string

text   lorem ipsum dolor sit amet blablah
string bla
split  ['bla']
lines  ['lor', 'em', 'ips', 'um', 'dol', 'or', 'sit', '', 'ame', 't', 'bla', 'bla
string

['lor', 'em', 'ips', 'um', 'dol', 'or', 'sit', '', 'ame', 't', 'bla', 'bla', 'h']

25
text   lorem ipsum dolor sit amet blablah
string lorem
split  ['lorem', '']
lines  ['lorem']
string

text   lorem ipsum dolor sit amet blablah
string ipsum
split  ['ipsum', '']
lines  ['lorem', 'ipsum']
string

text   lorem ipsum dolor sit amet blablah
string dolor
split  ['dolor', '']
lines  ['lorem', 'ipsum', 'dolor']
string

text   lorem ipsum dolor sit amet blablah
string sit am
split  ['sit', 'am']
lines  ['lorem', 'ipsum', 'dolor', 'sit']
string am

text   lorem ipsum dolor sit amet blablah
string amet b
split  ['amet', 'b']
lines  ['lorem', 'ipsum', 'dolor', 'sit', 'amet']
string b

text   lorem ipsum dolor sit amet blablah
string blabla
split  ['blabla']
lines  ['lorem', 'ipsum', 'dolor', 'sit', 'amet', 'blabla']
string

['lorem', 'ipsum', 'dolor', 'sit', 'amet', 'blabla', 'h']

55
text   lorem ipsum dolor sit amet blablah
string lorem ipsum
split  ['lorem ipsum', '']
lines  ['lorem ipsum']
string

text   lorem ipsum dolor sit amet blablah
string dolor sit am
split  ['dolor sit', 'am']
lines  ['lorem ipsum', 'dolor sit']
string am

text   lorem ipsum dolor sit amet blablah
string amet blablah
split  ['amet', 'blablah']
lines  ['lorem ipsum', 'dolor sit', 'amet']
string blablah

['lorem ipsum', 'dolor sit', 'amet', 'blablah']

80
text   lorem ipsum dolor sit amet blablah
string lorem ipsum dolor
split  ['lorem ipsum', 'dolor']
lines  ['lorem ipsum']
string dolor

text   lorem ipsum dolor sit amet blablah
string dolor sit amet bl
split  ['dolor sit amet', 'bl']
lines  ['lorem ipsum', 'dolor sit amet']
string bl

['lorem ipsum', 'dolor sit amet', 'blablah']

100
text   lorem ipsum dolor sit amet blablah
string lorem ipsum dolor sit
split  ['lorem ipsum dolor', 'sit']
lines  ['lorem ipsum dolor']
string sit

['lorem ipsum dolor', 'sit amet blablah']

120
text   lorem ipsum dolor sit amet blablah
string lorem ipsum dolor sit ame
split  ['lorem ipsum dolor sit', 'ame']
lines  ['lorem ipsum dolor sit']
string ame

['lorem ipsum dolor sit', 'amet blablah']