tmux: SIXEL integration (for mlterm / RLogin, not works on XTerm)

tmux-SIXEL.patch

diff --git a/input.c b/input.c
index d1ff17f..33fad13 100644
--- a/input.c
+++ b/input.c
@@ -1805,6 +1805,7 @@ input_dcs_dispatch(struct input_ctx *ictx)
 {
 	const char	prefix[] = "tmux;";
 	const u_int	prefix_len = (sizeof prefix) - 1;
+	u_char *p;
 
 	if (ictx->flags & INPUT_DISCARD)
 		return (0);
@@ -1818,6 +1819,15 @@ input_dcs_dispatch(struct input_ctx *ictx)
 		    ictx->input_buf + prefix_len, ictx->input_len - prefix_len);
 	}
 
+	for (p = ictx->input_buf; p != ictx->input_buf + ictx->input_len; p++) {
+		if ((*p >= 0 && *p <= 9) || *p == ';')
+			continue;
+		if (*p != 'q')
+			break;
+		screen_write_sixel(&ictx->ctx,
+		                   ictx->input_buf, ictx->input_len);
+	}
+
 	return (0);
 }
 
diff --git a/screen-write.c b/screen-write.c
index e38c9f5..7a756c7 100644
--- a/screen-write.c
+++ b/screen-write.c
@@ -1096,6 +1096,18 @@ screen_write_setselection(struct screen_write_ctx *ctx, u_char *str, u_int len)
 }
 
 void
+screen_write_sixel(struct screen_write_ctx *ctx, u_char *str, u_int len)
+{
+	struct tty_ctx		 ttyctx;
+
+	screen_write_initctx(ctx, &ttyctx, 0);
+	ttyctx.ptr = str;
+	ttyctx.num = len;
+
+	tty_write(tty_cmd_write_sixel, &ttyctx);
+}
+
+void
 screen_write_rawstring(struct screen_write_ctx *ctx, u_char *str, u_int len)
 {
 	struct tty_ctx		 ttyctx;
diff --git a/tmux.h b/tmux.h
index f0fef0d..6363f35 100644
--- a/tmux.h
+++ b/tmux.h
@@ -368,6 +368,7 @@ enum tty_code_code {
 	TTYC_KUP5,
 	TTYC_KUP6,
 	TTYC_KUP7,
+	TTYC_MGC,	/* clear_margins, MC */
 	TTYC_MS,	/* modify xterm(1) selection */
 	TTYC_OP,	/* orig_pair, op */
 	TTYC_REV,	/* enter_reverse_mode, mr */
@@ -382,6 +383,7 @@ enum tty_code_code {
 	TTYC_SITM,	/* enter_italics_mode, it */
 	TTYC_SMACS,	/* enter_alt_charset_mode, as */
 	TTYC_SMCUP,	/* enter_ca_mode, ti */
+	TTYC_SMGLR,	/* set_lr_margin, ML */
 	TTYC_SMKX,	/* keypad_xmit, ks */
 	TTYC_SMSO,	/* enter_standout_mode, so */
 	TTYC_SMUL,	/* enter_underline_mode, us */
@@ -1127,6 +1129,8 @@ struct tty {
 
 	u_int		 cx;
 	u_int		 cy;
+	u_int		 pixel_x;
+	u_int		 pixel_y;
 	u_int		 cstyle;
 	char		*ccolour;
 
@@ -1641,6 +1645,7 @@ void	tty_cmd_linefeed(struct tty *, const struct tty_ctx *);
 void	tty_cmd_utf8character(struct tty *, const struct tty_ctx *);
 void	tty_cmd_reverseindex(struct tty *, const struct tty_ctx *);
 void	tty_cmd_setselection(struct tty *, const struct tty_ctx *);
+void	tty_cmd_write_sixel(struct tty *, const struct tty_ctx *);
 void	tty_cmd_rawstring(struct tty *, const struct tty_ctx *);
 void	tty_bell(struct tty *);
 
@@ -2070,6 +2075,7 @@ void	 screen_write_clearscreen(struct screen_write_ctx *);
 void	 screen_write_clearhistory(struct screen_write_ctx *);
 void	 screen_write_cell(struct screen_write_ctx *, const struct grid_cell *);
 void	 screen_write_setselection(struct screen_write_ctx *, u_char *, u_int);
+void	 screen_write_sixel(struct screen_write_ctx *, u_char *, u_int);
 void	 screen_write_rawstring(struct screen_write_ctx *, u_char *, u_int);
 
 /* screen-redraw.c */
diff --git a/tty-term.c b/tty-term.c
index d177c19..13cd982 100644
--- a/tty-term.c
+++ b/tty-term.c
@@ -215,6 +215,7 @@ const struct tty_term_code_entry tty_term_codes[NTTYCODE] = {
 	{ TTYC_KUP5, TTYCODE_STRING, "kUP5" },
 	{ TTYC_KUP6, TTYCODE_STRING, "kUP6" },
 	{ TTYC_KUP7, TTYCODE_STRING, "kUP7" },
+	{ TTYC_MGC, TTYCODE_STRING, "mgc" },
 	{ TTYC_MS, TTYCODE_STRING, "Ms" },
 	{ TTYC_OP, TTYCODE_STRING, "op" },
 	{ TTYC_REV, TTYCODE_STRING, "rev" },
@@ -229,6 +230,7 @@ const struct tty_term_code_entry tty_term_codes[NTTYCODE] = {
 	{ TTYC_SITM, TTYCODE_STRING, "sitm" },
 	{ TTYC_SMACS, TTYCODE_STRING, "smacs" },
 	{ TTYC_SMCUP, TTYCODE_STRING, "smcup" },
+	{ TTYC_SMGLR, TTYCODE_STRING, "smglr" },
 	{ TTYC_SMKX, TTYCODE_STRING, "smkx" },
 	{ TTYC_SMSO, TTYCODE_STRING, "smso" },
 	{ TTYC_SMUL, TTYCODE_STRING, "smul" },
diff --git a/tty.c b/tty.c
index 63380c2..8176499 100644
--- a/tty.c
+++ b/tty.c
@@ -90,6 +90,8 @@ tty_resize(struct tty *tty)
 	struct winsize	ws;
 	u_int		sx, sy;
 
+	memset(&ws, 0, sizeof(ws));
+
 	if (ioctl(tty->fd, TIOCGWINSZ, &ws) != -1) {
 		sx = ws.ws_col;
 		if (sx == 0)
@@ -97,6 +99,8 @@ tty_resize(struct tty *tty)
 		sy = ws.ws_row;
 		if (sy == 0)
 			sy = 24;
+		tty->pixel_x = ws.ws_xpixel;
+		tty->pixel_y = ws.ws_ypixel;
 	} else {
 		sx = 80;
 		sy = 24;
@@ -831,7 +835,11 @@ tty_cmd_clearcharacter(struct tty *tty, const struct tty_ctx *ctx)
 void
 tty_cmd_insertline(struct tty *tty, const struct tty_ctx *ctx)
 {
-	if (!tty_pane_full_width(tty, ctx) || tty_fake_bce(tty, ctx->wp) ||
+	struct screen *s = ctx->wp->screen;
+
+	if ((!tty_term_has(tty->term, TTYC_SMGLR) &&
+		 !tty_pane_full_width(tty, ctx)) || 
+	    tty_fake_bce(tty, ctx->wp) ||
 	    !tty_term_has(tty->term, TTYC_CSR) ||
 	    !tty_term_has(tty->term, TTYC_IL1)) {
 		tty_redraw_region(tty, ctx);
@@ -840,16 +848,25 @@ tty_cmd_insertline(struct tty *tty, const struct tty_ctx *ctx)
 
 	tty_attributes(tty, &grid_default_cell, ctx->wp);
 
+	if (!tty_pane_full_width(tty, ctx))
+		tty_putcode2(tty, TTYC_SMGLR,
+		             ctx->xoff, ctx->xoff + screen_size_x(s) - 1);
 	tty_region_pane(tty, ctx, ctx->orupper, ctx->orlower);
 	tty_cursor_pane(tty, ctx, ctx->ocx, ctx->ocy);
 
 	tty_emulate_repeat(tty, TTYC_IL, TTYC_IL1, ctx->num);
+	if (!tty_pane_full_width(tty, ctx))
+		tty_putcode(tty, TTYC_MGC);
 }
 
 void
 tty_cmd_deleteline(struct tty *tty, const struct tty_ctx *ctx)
 {
-	if (!tty_pane_full_width(tty, ctx) || tty_fake_bce(tty, ctx->wp) ||
+	struct screen *s = ctx->wp->screen;
+
+	if ((!tty_term_has(tty->term, TTYC_SMGLR) &&
+		 !tty_pane_full_width(tty, ctx)) || 
+	    tty_fake_bce(tty, ctx->wp) ||
 	    !tty_term_has(tty->term, TTYC_CSR) ||
 	    !tty_term_has(tty->term, TTYC_DL1)) {
 		tty_redraw_region(tty, ctx);
@@ -858,10 +875,15 @@ tty_cmd_deleteline(struct tty *tty, const struct tty_ctx *ctx)
 
 	tty_attributes(tty, &grid_default_cell, ctx->wp);
 
+	if (!tty_pane_full_width(tty, ctx))
+		tty_putcode2(tty, TTYC_SMGLR,
+		             ctx->xoff, ctx->xoff + screen_size_x(s) - 1);
 	tty_region_pane(tty, ctx, ctx->orupper, ctx->orlower);
 	tty_cursor_pane(tty, ctx, ctx->ocx, ctx->ocy);
 
 	tty_emulate_repeat(tty, TTYC_DL, TTYC_DL1, ctx->num);
+	if (!tty_pane_full_width(tty, ctx))
+		tty_putcode(tty, TTYC_MGC);
 }
 
 void
@@ -916,10 +938,14 @@ tty_cmd_clearstartofline(struct tty *tty, const struct tty_ctx *ctx)
 void
 tty_cmd_reverseindex(struct tty *tty, const struct tty_ctx *ctx)
 {
+	struct screen *s = ctx->wp->screen;
+
 	if (ctx->ocy != ctx->orupper)
 		return;
 
-	if (!tty_pane_full_width(tty, ctx) || tty_fake_bce(tty, ctx->wp) ||
+	if ((!tty_term_has(tty->term, TTYC_SMGLR) &&
+		 !tty_pane_full_width(tty, ctx)) || 
+	    tty_fake_bce(tty, ctx->wp) ||
 	    !tty_term_has(tty->term, TTYC_CSR) ||
 	    !tty_term_has(tty->term, TTYC_RI)) {
 		tty_redraw_region(tty, ctx);
@@ -928,21 +954,29 @@ tty_cmd_reverseindex(struct tty *tty, const struct tty_ctx *ctx)
 
 	tty_attributes(tty, &grid_default_cell, ctx->wp);
 
+	if (!tty_pane_full_width(tty, ctx))
+		tty_putcode2(tty, TTYC_SMGLR,
+		             ctx->xoff, ctx->xoff + screen_size_x(s) - 1);
 	tty_region_pane(tty, ctx, ctx->orupper, ctx->orlower);
 	tty_cursor_pane(tty, ctx, ctx->ocx, ctx->orupper);
 
 	tty_putcode(tty, TTYC_RI);
+	if (!tty_pane_full_width(tty, ctx))
+		tty_putcode(tty, TTYC_MGC);
 }
 
 void
 tty_cmd_linefeed(struct tty *tty, const struct tty_ctx *ctx)
 {
 	struct window_pane	*wp = ctx->wp;
+	struct screen		*s = wp->screen;
 
 	if (ctx->ocy != ctx->orlower)
 		return;
 
-	if (!tty_pane_full_width(tty, ctx) || tty_fake_bce(tty, wp) ||
+	if ((!tty_term_has(tty->term, TTYC_SMGLR) &&
+		 !tty_pane_full_width(tty, ctx)) || 
+	    tty_fake_bce(tty, ctx->wp) ||
 	    !tty_term_has(tty->term, TTYC_CSR)) {
 		if (tty_large_region(tty, ctx))
 			wp->flags |= PANE_REDRAW;
@@ -961,10 +995,15 @@ tty_cmd_linefeed(struct tty *tty, const struct tty_ctx *ctx)
 
 	tty_attributes(tty, &grid_default_cell, wp);
 
+	if (!tty_pane_full_width(tty, ctx))
+		tty_putcode2(tty, TTYC_SMGLR,
+		             ctx->xoff, ctx->xoff + screen_size_x(s) - 1);
 	tty_region_pane(tty, ctx, ctx->orupper, ctx->orlower);
 	tty_cursor_pane(tty, ctx, ctx->ocx, ctx->ocy);
 
 	tty_putc(tty, '\n');
+	if (!tty_pane_full_width(tty, ctx))
+		tty_putcode(tty, TTYC_MGC);
 }
 
 void
@@ -1145,6 +1184,38 @@ tty_cmd_setselection(struct tty *tty, const struct tty_ctx *ctx)
 }
 
 void
+tty_cmd_write_sixel(struct tty *tty, const struct tty_ctx *ctx)
+{
+	u_char	*str = ctx->ptr;
+	u_char	*start = str;
+	u_char	*end = str + ctx->num;
+	u_char	*p = str;
+	int	pixel_y = 6;
+	struct screen *s = ctx->wp->screen;
+
+	if (s != NULL && tty->pixel_y > 0) {
+		tty_region_pane(tty, ctx, ctx->orupper, ctx->orlower);
+		if (!tty_pane_full_width(tty, ctx))
+			tty_putcode2(tty, TTYC_SMGLR, ctx->xoff,
+			             ctx->xoff + screen_size_x(s) - 1);
+		tty_cursor_pane(tty, ctx, ctx->ocx, ctx->ocy);
+		bufferevent_write(tty->event, "\033P", 2);
+		bufferevent_write(tty->event, str, ctx->num);
+		bufferevent_write(tty->event, "\033\\", 2);
+		if (!tty_pane_full_width(tty, ctx))
+			tty_putcode(tty, TTYC_MGC);
+		tty_region_pane(tty, ctx, ctx->orupper, ctx->orlower);
+		tty_cursor_pane(tty, ctx, ctx->ocx, ctx->ocy);
+		for (p = start; p != end; ++p)
+			if (*p == '-')
+				pixel_y += 6;
+		s->cy += (pixel_y - 1) * tty->sy / tty->pixel_y + 1;
+		if (s->cy > screen_size_y(s) - 1)
+			s->cy = screen_size_y(s) - 1;
+        }
+}
+
+void
 tty_cmd_rawstring(struct tty *tty, const struct tty_ctx *ctx)
 {
 	u_int	 i;

tmux.conf

set -ga terminal-overrides ',xterm*:smglr=\E7\E[?69h\E[%i%p1%d;%p2%ds\E8:mgc=\E7\E[?69l\E8'

Unfortunately, it looks like this patch does not work for me using tmux under yaft. I receive no errors; rather, img2sixel simply produces nothing, as if I were on a terminal that does not provide sixel-support.

A valiant effort though it is! However, given the tmux devs' unwillingness to add support to mainline, I'm exploring some other options as replacements and namely have my eyes on dvtm/abduco.

@HalosGhost It reproduced for me.
The reason is that the master branch of yaft does not return terminal pixel size over TIOCGWINSZ.
yaft develop branch seemes to do it.
uobikiemukot/yaft@9bb83c1#diff-8c689842501e39ed6229d6ec73103c42R121
You should use the develop branch or apply it.
https://gist.github.com/saitoha/2c662697f972170150ab

Even if you do above solution, it won't works with tmux's vertical split feature, because yaft does not supports DECLRMM/DECSLRM.