So that it can determine if it should subtract 1 from $FZF_PREVIEW_LINES
to avoid scrolling issue of Sixel image that touches the bottom of the
screen.
Progress:
* Sixel image can now be displayed with other text, and is scrollable
* If an image can't be displayed entirely due to the scroll offset, fzf
will render a wireframe to indicate that an image should be displayed
* Renamed $FZF_PREVIEW_{WIDTH,HEIGHT} to $FZF_PREVIEW_PIXEL_{WIDTH,HEIGHT}
for clarity
* Added bin/fzf-preview.sh script to demonstrate how to display an image
using Kitty or Sixel protocol
An example:
ls *.jpg | fzf --preview='seq $((FZF_PREVIEW_LINES*9/10)); fzf-preview.sh {}; seq 100'
A known issue:
* If you reduce the size of the preview window, the image may extend
beyond the preview window