Change the way the grid is stored, previously it was:
- a two-dimensional array of cells;
- a two-dimensional array of utf8 data;
- an array of line lengths.
Now it is a single array of a new struct grid_line each of which represents a
line and contains the length and an array of cells and an array of utf8 data.
This will make it easier to add additional per-line members, such as flags.
If colours are not supported by the terminal, try to emulate a coloured
background by setting or clearing the reverse attribute.
This makes a few applications which don't use the reverse attribute themselves
a little happier, and allows the status, message and mode options to have
default attributes and fg/bg options that work as expected when set as reverse.
Add a terminal-overrides session option allowing individual terminfo(5) entries
to be overridden. The 88col/256col checks are now moved into the default
setting and out of the code.
Also remove a couple of old workarounds for xterm and rxvt which are no longer
necessary (tmux can emulate them if missing).
enum tty_cmd is only used as an index into the array of command function
pointers, so remove it and use the function pointers directly to represent
themselves.
normal eight-bit output is wrong, separate it into a different function. Fixes
spacing when mixing UTF-8 with some escape sequences, notably the way w3m does
it.
redraw the entire window. Also add a flag to skip updating the window any
further if it is scheduled to be redrawn. This has the effect of batching
multiple redraws together.
issues - particularly, don't mix with manual pane resizing and be careful when
viewing from multiple clients; generally cycling the layout a few times will
fix most problems. Getting this in for testing while I think about how to deal
with manual mode.
Split window as normal and cycle the layouts with C-b space. Some of the
layouts will work better when swap-pane comes along.
as UTF-8 in a separate array, the code does a lookup into this every time it
gets to a UTF-8 cell. Zero width characters are just appended onto the UTF-8
data for the previous cell. This also means that almost no bytes extra are
wasted non-Unicode data (yay).
Still some oddities, such as copy mode skips over wide characters in a strange
way, and the code could do with some tidying.
Split grid into two arrays, one containing grid attributes/flags/colours (keeps
the name grid_cell for now) and a separate with the character data (called
text). The text is stored as a u_short but is treated as a uint64_t elsewhere;
eventually the grid will have two arrays.
I'm not happy with the naming so that might change.
Still need to decide where to go from here. I'm not sure whether to combine
the peek/set functions together, and also whether to continue to treat the
text as a uint64_t (and convert to/from Unicode) or make it a char array
(of size one when UTF-8 disabled, eight when enabled) and keep everything
as UTF-8.
Also since UTF-8 will eventually become an attribute of the grid itself it
might be nice to move all the padding crap into grid.c.
