Post by Omar Rizwan (@omar@social.omar.website)

Omar Rizwan @omar

woah -- it's like it's an intermingling of levels of abstraction (the world of display and pixels vs. the world of characters and text)

Function: pixel-fill-region start end pixel-width ¶
Most Emacs buffers use monospaced text, so all the filling functions (like fill-region) work based on the number of characters and char-width. However, Emacs can render other types of things, like text that contains images and using proportional fonts, and the pixel-fill-region exists to handle that. It fills the region of text between start and end at pixel granularity, so text using variable-pitch fonts or several different fonts looks filled regardless of different character sizes. The argument pixel-width specifies the maximum pixel width a line is allowed to have after filling; it is the pixel-resolution equivalent of the fill-column in fill-region. For instance, this Lisp snippet will insert text using a proportional font, and then fill this to be no wider than 300 pixels:

(insert (propertize
"This is a sentence that's ends here."
'face 'variable-pitch))
(pixel-fill-region (point) (point-max) 300)

Function: pixel-fill-region start end pixel-width ¶
Most Emacs buffers use monospaced text, so all the filling functions (like fill-region) work based on the number of characters and char-width. However, Emacs can render other types of things, like text that contains images and using proportional fonts, and the pixel-fill-region exists to handle that. It fills the region of text between start and end at pixel granularity, so text using variable-pitch fonts or several different fonts looks filled regardless of different character sizes. The argument pixel-width specifies the maximum pixel width a line is allowed to have after filling; it is the pixel-resolution equivalent of the fill-column in fill-region. For instance, this Lisp snippet will insert text using a proportional font, and then fill this to be no wider than 300 pixels:

(insert (propertize
"This is a sentence that's ends here."
'face 'variable-pitch))
(pixel-fill-region (point) (point-max) 300)