together instead of handling them one by one. This is significantly
faster. Sequences are terminated when we reach the end of the line, fill
the internal buffer, or a different character is seen by the input
parser (an escape sequence, or UTF-8).
Rather than writing collected sequences out immediately, hold them until
it is necessary (another screen modification, or we consume all
available data). This means we can discard changes that would have no
effect (for example, lines that would just be scrolled off the screen or
cleared). This reduces the total amount of data we write out to the
terminal - not important for fast terminals, but a big help with slow
(like xterm).
main issue is that if we have two panes, A with 1002 and B with 1003, we
need to set 1003 outside tmux in order to get all the mouse events, but
then we need to suppress the ones that pane A doesn't want. This is easy
in SGR mouse mode, because buttons == 3 is only used for movement events
(for other events the trailing m/M marks a release instead), but in
normal mouse mode we can't tell so easily. So for that, look at the
previous event instead - if it is drag+release as well, then the current
event is a movement event.
supports them (that is, if it advertises itself as a VT420 - probably
just xterm). These are the vertical equivalent of the scroll region and
allow much faster scrolling of panes that do not take up the full width
of the terminal.
sequences (notable EL and ED but also IL, DL, ICH, DCH) create blank
cells using the current background colour rather than the default
colour.
On modern systems BCE doesn't really have many benefits, but most other
terminals now support it, some (lazy) applications rely on it, and it is
not hard to include now that we have pane background colours anyway.
Mostly written by Sean Haugh.
instead track them as change (dirty) and update them once at the end,
saves much time if repeatedly writing the same cell. Also fix comparison
of cells being equal in a few places (memcmp is not enough).
wasting unnecessary space. The 'Tc' flag must be set in the external
TERM entry (using terminal-overrides or a custom terminfo entry), if not
tmux will map to the closest of the 256 or 16 colour palettes.
Mostly from Suraj N Kurapati, based on a diff originally by someone else.
