This commit decomposes the main get_semantic_zones method into two
parts:
* A per-line portion, where the line ranges are cached (invalidated on
change)
* The overall screen portion, where the line ranges are merged
This changes the overall complexity of computing zones from
O(width * scrollback-height)
To an incremental:
O((width * number of changed lines since last query) + scrollback-height)
You can see some samples of elapsed time below; those show the times for
running both the old and the new implementation on the same data. The
number of lines/zones in the scrollback increases with each call and you
can see that the new implementation is a bit faster anyway at low
volumes but is significantly faster as the number of lines/zones
increases, because the amount of work is reduced.
```
get_semantic_zones: 71.708µs
get_semantic_zones_new: 59.041µs
get_semantic_zones: 71.166µs
get_semantic_zones_new: 9.166µs
get_semantic_zones: 44.291µs
get_semantic_zones_new: 4.208µs
get_semantic_zones: 69.791µs
get_semantic_zones_new: 10.291µs
get_semantic_zones: 59.375µs
get_semantic_zones_new: 7.958µs
get_semantic_zones: 52.5µs
get_semantic_zones_new: 4.5µs
get_semantic_zones: 91.791µs
get_semantic_zones_new: 20.916µs
get_semantic_zones: 229.916µs
get_semantic_zones_new: 109.208µs
get_semantic_zones: 224.125µs
get_semantic_zones_new: 15.208µs
get_semantic_zones: 291.791µs
get_semantic_zones_new: 11.833µs
get_semantic_zones: 238.875µs
get_semantic_zones_new: 12.625µs
get_semantic_zones: 468.458µs
get_semantic_zones_new: 126.583µs
get_semantic_zones: 460.5µs
get_semantic_zones_new: 25.666µs
get_semantic_zones: 358.291µs
get_semantic_zones_new: 19.541µs
get_semantic_zones: 436.833µs
get_semantic_zones_new: 17.875µs
get_semantic_zones: 313.166µs
get_semantic_zones_new: 15.25µs
get_semantic_zones: 333.958µs
get_semantic_zones_new: 16.541µs
get_semantic_zones: 364.666µs
get_semantic_zones_new: 14.041µs
```
We budget size based on the x_advance, which can be 1 pixel less
than the width of the glyph texture, so we could often end up
omitting the last character in "Launcher" or "default" in the
tab title or right status area.
This commit uses x_advance in both places.
Make the scrolling mostly independent of the active row; adjust
the top row when hitting the top/bottom edges of the display.
Mouse movement no longer changes the scroll position. Instead,
the wheel is used to scroll the list.
refs: https://github.com/wez/wezterm/issues/1485
* #1457 Initial commit compiles but doesn't yet work
* #1457 Fix cell offsets
* #1457 refactor, ClickPosition
* fix nits
* #1457 filter per-pixel motion when not in SGR-Pixels mode
* Much cleaner match condition for filtering mouse events based on encoding protocol
I generated nerdfonts_data.rs with this shell script; it uses `i_all.sh`
from the nerdfonts repo to get the base mapping:
```
source ./lib/i_all.sh
echo "//! Data mapping nerd font symbol names to their char codepoints"
echo "pub const NERD_FONT_GLYPHS: &[(&str, char)] = &["
for var in "${!i@}"; do
# trim 'i_' prefix
glyph_name=${var#*_}
glyph_char=${!var}
glyph_code=$(printf "%x" "'$glyph_char'")
echo "(\"$glyph_name\", '\u{$glyph_code}'), // $glyph_char"
done
echo "];"
```
Then intent is to use it in wezterm:
```
local wezterm = require 'wezterm'
wezterm.log_info(wezterm.nerdfonts.dev_mozilla)
```
Built using:
```
./FontForge-2020-11-07-21ad4a1-x86_64.AppImage --script $PWD/font-patcher "$PWD/src/unpatched-fonts/NerdFontsSymbolsOnly/NerdFontsSymbolsOnly Template 1000 em.ttf" --powerline --use-single-width-glyphs -out /tmp/nerd-fonts-out --fontawesome --fontawesomeextension --fontlinux --octicons --codicons --powersymbols --powerline --powerlineextra --mdi --weathericons
```
which is everything *except* Pomicons at the time of writing, pending
clarifications of its distribution license
(https://github.com/ryanoasis/nerd-fonts/issues/266)
refs: https://github.com/wez/wezterm/issues/1521
It's a little ambiguous whether we should cancel the mode when moving
the cursor explicitly; I opted to do it when we move it due to newline
processing, or when its y position is changed.
refs: #1539
