term: save only changes to the bottom line

The bottom line is where we draw the spinner, so we're only interested
in screen draws that affect that part of the screen (so that we may
restore it after having drawn the spinner there).

Given recent changes, redraws should be less frequent than updates, so
we lazily store the utf32 encoded line contents in state, instead of
the eagerly converted utf8 version.
This commit is contained in:
fang 2021-02-18 20:03:18 +01:00
parent d974d4cc4e
commit b936e1d928
No known key found for this signature in database
GPG Key ID: EB035760C1BBA972
2 changed files with 107 additions and 58 deletions

View File

@ -145,8 +145,7 @@
} siz;
struct {
c3_y* lin_y; // current line (utf8)
c3_w byt_w; // utf8 line-length
c3_w* lin_w; // bottom line (utf32)
c3_w wor_w; // utf32 line-length
c3_w rus_w; // cursor position (row)
c3_w cus_w; // cursor position (column)

View File

@ -219,8 +219,7 @@ u3_term_log_init(void)
// Initialize mirror and accumulator state.
//
{
uty_u->tat_u.mir.lin_y = 0;
uty_u->tat_u.mir.byt_w = 0;
uty_u->tat_u.mir.lin_w = 0;
uty_u->tat_u.mir.wor_w = 0;
uty_u->tat_u.mir.rus_w = 0;
uty_u->tat_u.mir.cus_w = 0;
@ -469,17 +468,32 @@ _term_it_send_cord(u3_utty* uty_u,
u3z(txt);
}
/* _term_it_free_line(): wipe line stored by _term_it_save_line
*/
static void
_term_it_free_line(u3_utty* uty_u)
{
c3_free(uty_u->tat_u.mir.lin_w);
uty_u->tat_u.mir.lin_w = 0;
uty_u->tat_u.mir.wor_w = 0;
}
/* _term_it_clear_line(): clear line of cursor
*/
static void
_term_it_clear_line(u3_utty* uty_u)
{
//REVIEW why this conditional?
if ( uty_u->tat_u.siz.col_l ) {
_term_it_dump(uty_u, TERM_LIT("\r"));
_term_it_dump_buf(uty_u, &uty_u->ufo_u.out.el_u);
_term_it_dump_buf(uty_u, &uty_u->ufo_u.out.rc_u);
}
uty_u->tat_u.mir.wor_w = 0;
// if we're clearing the bottom line, clear our mirror of it too
//
if ( 0 == uty_u->tat_u.mir.rus_w ) {
_term_it_free_line(uty_u);
}
}
@ -513,51 +527,10 @@ _term_it_move_cursor(u3_utty* uty_u, c3_w row_w, c3_w col_w)
uty_u->tat_u.mir.cus_w = col_w;
}
/* _term_it_show_line(): render current line.
/* _term_it_show_line(): print at cursor
*/
static void
_term_it_show_line(u3_utty* uty_u, c3_w wor_w)
{
u3_utat* tat_u = &uty_u->tat_u;
// we have to reallocate the current line on write,
// or we have a data race if a) the write is async,
// and b) a new output line arrives before the write completes.
//
{
c3_w len_w = tat_u->mir.byt_w;
c3_y* hun_y = c3_malloc(len_w);
memcpy(hun_y, tat_u->mir.lin_y, len_w);
_term_it_send(uty_u, len_w, hun_y);
_term_it_dump_buf(uty_u, &uty_u->ufo_u.out.rc_u);
}
// XX refactor to avoid updating state
//
tat_u->mir.wor_w = wor_w;
}
/* _term_it_refresh_line(): refresh current line.
*/
static void
_term_it_refresh_line(u3_utty* uty_u)
{
u3_utat* tat_u = &uty_u->tat_u;
c3_w wor_w = tat_u->mir.wor_w;
_term_it_move_cursor(uty_u, 0, 0);
_term_it_clear_line(uty_u);
_term_it_show_line(uty_u, wor_w);
_term_it_dump_buf(uty_u, &uty_u->ufo_u.out.rc_u);
}
/* _term_it_set_line(): set current line.
*/
static void
_term_it_set_line(u3_utty* uty_u,
c3_w* lin_w,
c3_w wor_w)
_term_it_show_line(u3_utty* uty_u, c3_w* lin_w, c3_w wor_w)
{
u3_utat* tat_u = &uty_u->tat_u;
c3_y* hun_y = (c3_y*)lin_w;
@ -595,12 +568,84 @@ _term_it_set_line(u3_utty* uty_u,
}
}
c3_free(tat_u->mir.lin_y);
tat_u->mir.lin_y = hun_y;
tat_u->mir.byt_w = byt_w;
tat_u->mir.wor_w = wor_w;
//NOTE lin_w freed through hun_y by _send
_term_it_send(uty_u, byt_w, hun_y);
_term_it_dump_buf(uty_u, &uty_u->ufo_u.out.rc_u);
}
_term_it_show_line(uty_u, wor_w);
/* _term_it_refresh_line(): refresh current line.
*/
static void
_term_it_refresh_line(u3_utty* uty_u) //TODO rename restore
{
u3_utat* tat_u = &uty_u->tat_u;
c3_w* lin_w = tat_u->mir.lin_w;
c3_w wor_w = tat_u->mir.wor_w;
if ( (0 != lin_w) && (0 < wor_w) ) {
// we have to reallocate the current line on write,
// or we have a data race if a) the write is async,
// and b) a new output line arrives before the write completes.
// also, _show_line would free it.
//
c3_w* hun_w = c3_malloc( sizeof(c3_w) * wor_w );
memcpy(hun_w, lin_w, wor_w * sizeof(c3_w));
_term_it_send_csi(uty_u, 'H', 2, tat_u->siz.row_l, 0);
_term_it_dump_buf(uty_u, &uty_u->ufo_u.out.el_u);
_term_it_show_line(uty_u, hun_w, wor_w);
}
}
/* _term_it_save_line(): store line if relevant to internal logic
* RETAINs lin_w
*/
static void
_term_it_save_line(u3_utty* uty_u, c3_w* lin_w, c3_w wor_w)
{
u3_utat* tat_u = &uty_u->tat_u;
// keep track of changes to bottom-most line, to aid spinner drawing logic
//
if ( 0 == tat_u->mir.rus_w ) {
c3_w* nip_w = tat_u->mir.lin_w;
c3_w wod_w = tat_u->mir.wor_w;
c3_w off_w = tat_u->mir.cus_w;
c3_w wyd_w = off_w + wor_w;
// if we have no buffer, make one
//
if ( 0 == nip_w ) {
nip_w = c3_malloc( sizeof(c3_w) * wyd_w );
wod_w = wyd_w;
// initialize offset with spaces
//
for ( c3_w i_w = 0; i_w < off_w; i_w++ ) {
nip_w[i_w] = ' ';
}
}
// if we have a buffer, but it's too short, make a bigger one
//
else if ( wyd_w > wod_w ) {
c3_w* nic_w = c3_malloc( sizeof(c3_w) * wyd_w );
memcpy(nic_w, nip_w, wod_w);
// initialize fresh offset with spaces
//
for ( c3_w i_w = wod_w; i_w < off_w; i_w++ ) {
nic_w[i_w] = ' ';
}
c3_free(nip_w);
nip_w = nic_w;
wod_w = wyd_w;
}
memcpy(nip_w + off_w, lin_w, sizeof(c3_w) * wor_w);
tat_u->mir.lin_w = nip_w;
tat_u->mir.wor_w = wod_w;
}
}
/* _term_it_show_more(): render newline, moving cursor down
@ -613,13 +658,18 @@ _term_it_show_more(u3_utty* uty_u)
}
else {
_term_it_dump(uty_u, TERM_LIT("\r\n"));
_term_it_dump_buf(uty_u, &uty_u->ufo_u.out.sc_u);
}
uty_u->tat_u.mir.cus_w = 0;
if ( uty_u->tat_u.mir.rus_w > 0 ) {
uty_u->tat_u.mir.rus_w--;
}
_term_it_dump_buf(uty_u, &uty_u->ufo_u.out.sc_u);
else {
// newline at bottom of screen, so bottom line is now empty
//
_term_it_free_line(uty_u);
}
}
/* _term_it_path(): path for console file.
@ -1176,8 +1226,6 @@ u3_term_ef_ctlc(void)
_term_ovum_plan(uty_u->car_u, wir, cad);
}
_term_it_refresh_line(uty_u);
}
/* _term_it_put_value(): put numeric color value on lin_w.
@ -1378,7 +1426,8 @@ _term_it_show_stub(u3_utty* uty_u,
}
}
_term_it_set_line(uty_u, lin_w, i_w);
_term_it_save_line(uty_u, lin_w, i_w);
_term_it_show_line(uty_u, lin_w, i_w);
u3z(tub);
}
@ -1400,7 +1449,8 @@ _term_it_show_tour(u3_utty* uty_u,
}
}
_term_it_set_line(uty_u, lin_w, len_w);
_term_it_save_line(uty_u, lin_w, len_w);
_term_it_show_line(uty_u, lin_w, len_w);
u3z(lin);
}