Getting multiline_textbbox without an image

[awhitefox]

Hello, I have a question about calculating text bounding boxes.

Is there a method that can calculate a bounding box of a given text without an actual image object? The problem I having is that I need to have image size calculated beforehand. And to do this I need to get size of multiline text. So to create an image I need its size and to calculate the size I need to use multiline_textbbox(...) which is a method of ImageDraw which is instantiated using an image object.

Solutions I've already tried:

• Using ImageFont.getbbox(...) which produces a wrong result (height is ignored)

import os
from PIL import ImageFont

font = ImageFont.truetype(os.path.join('fonts', 'OpenSans-Regular.ttf'), 14)
print(font.getbbox('line 1'))  # (0, 4, 37, 15)
print(font.getbbox('line 1\nline 2\nline 3'))  # (0, 4, 127, 15)

• Using ImageFont.getsize_multiline(...) which works but produces a deprecation warning

import os
from PIL import ImageFont

font = ImageFont.truetype(os.path.join('fonts', 'OpenSans-Regular.ttf'), 14)
print(font.getsize_multiline('line 1\nline 2\nline 3'))  # (37, 53)

# DeprecationWarning: getsize_multiline is deprecated and will be removed in Pillow 10 (2023-07-01). Use ImageDraw.multiline_textbbox instead.

• Using a dummy image object which works but feels hacky

import os

from PIL import Image
from PIL import ImageFont
from PIL.ImageDraw import ImageDraw


font = ImageFont.truetype(os.path.join('fonts', 'OpenSans-Regular.ttf'), 14)
draw = ImageDraw(Image.new('RGB', (0, 0)))
print(draw.multiline_textbbox((0, 0), 'line 1', font))  # (0, 4, 37, 15)
print(draw.multiline_textbbox((0, 0), 'line 1\nline 2\nline 3', font))  # (0, 4, 37, 53)

Am I missing something or is there really no way to achieve this? And if there isn't why an image is required to calculate a size of text?

[nulano]

Using a dummy image object which works but feels hacky

This is currently the best option.

All multiline text operations, except for font.getsize_multiline (IIRC an exact duplicate of draw.multiline_textsize), are handled in ImageDraw which requires an Image. Moving the draw.multiline_text operation to ImageFont would require significant changes (either rewriting the function in C or taking a significant performance penalty), and draw.multiline_textbbox is quite long (~100 lines), too long to feel good about duplicating the code in ImageFont.