Package: emacs;
Reported by: Mohsin Kaleem <mohkale <at> kisara.moe>
Date: Fri, 21 Apr 2023 14:30:02 UTC
Severity: wishlist
Message #17 received at 62994 <at> debbugs.gnu.org (full text, mbox):
From: mohkale <at> kisara.moe To: 62994 <at> debbugs.gnu.org Cc: Mohsin Kaleem <mohkale <at> kisara.moe> Subject: [PATCH 2/3] Add support for styled underlines on tty frames Date: Fri, 21 Apr 2023 15:34:47 +0100
From: Mohsin Kaleem <mohkale <at> kisara.moe>
* src/dispextern.h (face): Convert tty_underline_p from bool to a
face_underline_type enumeration. Add a flag to check whether styled
underlines are available.
* src/termchar.c (tty_display_info): Add an entry for the escape
sequence to set the underline style on terminal frames.
* src/term.c (init_tty, tty_capable_p, turn_on_face): Read and save the
underline style escape sequence from the Smulx termcap (alternatively if
the Su flag is set use a default sequence). Allow checking for support
of styled underlines in the current terminal frame. Output the necessary
escape sequences to activate a styled underline on turn_on_face; this is
currently only used for the new special underline styles, a default
straight underline will still use the "us" termcap.
* src/xfaces.c (tty_supports_face_attributes_p, realize_tty_face):
Assert whether styled underlines are supported by the current terminal
on display-supports-face-attributes-p checks. Populate the correct
underline style in the face spec when realizing a face.
---
etc/NEWS | 16 +++++++++++++
src/dispextern.h | 3 ++-
src/term.c | 35 ++++++++++++++++++++++++----
src/termchar.h | 4 ++++
src/xfaces.c | 60 ++++++++++++++++++++++++++++++++++++++++++++----
5 files changed, 109 insertions(+), 9 deletions(-)
diff --git a/etc/NEWS b/etc/NEWS
index 62d2fdcd3a4..9f34927dfad 100644
--- a/etc/NEWS
+++ b/etc/NEWS
@@ -1916,6 +1916,22 @@ This command switches to the "*scratch*" buffer. If "*scratch*" doesn't
exist, the command creates it first. You can use this command if you
inadvertently delete the "*scratch*" buffer.
+---
+** Support for 'styled-underline' face attributes on TTY frames
+If your terminals termcap or terminfo database entry has the 'Su' or
+'Smulx' capability defined, Emacs will now emit the prescribed escape
+sequence necessary to render faces with styled underlines on TTY
+frames.
+
+Styled underlines are any underlines containing a non-default
+underline style. The available underline styles for TTY frames are
+'double', 'wave', 'dotted', and 'dashed'.
+
+The 'Smulx' capability should define the actual sequence needed to
+render styled underlines. If ommitted, but the 'Su' flag is defined,
+then a default sequence will be used. It's recommended to use 'Smulx'
+instead of 'Su', with priority being given to 'Smulx'.
+
** Debugging
---
diff --git a/src/dispextern.h b/src/dispextern.h
index 1dc84e32efc..6ea6f6170e4 100644
--- a/src/dispextern.h
+++ b/src/dispextern.h
@@ -1773,7 +1773,7 @@ #define FONT_TOO_HIGH(ft) \
string meaning the default color of the TTY. */
bool_bf tty_bold_p : 1;
bool_bf tty_italic_p : 1;
- bool_bf tty_underline_p : 1;
+ ENUM_BF (face_underline_type) tty_underline : 3;
bool_bf tty_reverse_p : 1;
bool_bf tty_strike_through_p : 1;
@@ -3365,6 +3365,7 @@ #define TTY_CAP_BOLD 0x04
#define TTY_CAP_DIM 0x08
#define TTY_CAP_ITALIC 0x10
#define TTY_CAP_STRIKE_THROUGH 0x20
+#define TTY_CAP_UNDERLINE_STYLED 0x32 & TTY_CAP_UNDERLINE
/***********************************************************************
diff --git a/src/term.c b/src/term.c
index 53ba2a231e4..0f0393780eb 100644
--- a/src/term.c
+++ b/src/term.c
@@ -1948,8 +1948,17 @@ turn_on_face (struct frame *f, int face_id)
OUTPUT1 (tty, tty->TS_enter_dim_mode);
}
- if (face->tty_underline_p && MAY_USE_WITH_COLORS_P (tty, NC_UNDERLINE))
- OUTPUT1_IF (tty, tty->TS_enter_underline_mode);
+ if (face->tty_underline && MAY_USE_WITH_COLORS_P (tty, NC_UNDERLINE)) {
+ if (face->tty_underline == FACE_UNDER_LINE ||
+ !tty->TF_set_underline_style) {
+ OUTPUT1_IF (tty, tty->TS_enter_underline_mode);
+ } else if (tty->TF_set_underline_style) {
+ char *p;
+ p = tparam(tty->TF_set_underline_style, NULL, 0, face->tty_underline, 0, 0, 0);
+ OUTPUT (tty, p);
+ xfree (p);
+ }
+ }
if (face->tty_strike_through_p
&& MAY_USE_WITH_COLORS_P (tty, NC_STRIKE_THROUGH))
@@ -1995,7 +2004,7 @@ turn_off_face (struct frame *f, int face_id)
if (face->tty_bold_p
|| face->tty_italic_p
|| face->tty_reverse_p
- || face->tty_underline_p
+ || face->tty_underline
|| face->tty_strike_through_p)
{
OUTPUT1_IF (tty, tty->TS_exit_attribute_mode);
@@ -2007,7 +2016,7 @@ turn_off_face (struct frame *f, int face_id)
{
/* If we don't have "me" we can only have those appearances
that have exit sequences defined. */
- if (face->tty_underline_p)
+ if (face->tty_underline)
OUTPUT_IF (tty, tty->TS_exit_underline_mode);
}
@@ -2036,6 +2045,9 @@ #define TTY_CAPABLE_P_TRY(tty, cap, TS, NC_bit) \
TTY_CAPABLE_P_TRY (tty,
TTY_CAP_UNDERLINE, tty->TS_enter_underline_mode,
NC_UNDERLINE);
+ TTY_CAPABLE_P_TRY (tty,
+ TTY_CAP_UNDERLINE_STYLED, tty->TF_set_underline_style,
+ NC_UNDERLINE);
TTY_CAPABLE_P_TRY (tty,
TTY_CAP_BOLD, tty->TS_enter_bold_mode, NC_BOLD);
TTY_CAPABLE_P_TRY (tty,
@@ -4250,6 +4262,21 @@ init_tty (const char *name, const char *terminal_type, bool must_succeed)
tty->TF_underscore = tgetflag ("ul");
tty->TF_teleray = tgetflag ("xt");
+ // Styled underlines.
+ //
+ // Support for this is provided either by the escape sequence in
+ // Smulx or the Su flag. The latter results in a common default
+ // escape sequence and is not recommended.
+#ifdef TERMINFO
+ tty->TF_set_underline_style = tigetstr("Smulx");
+ if (tty->TF_set_underline_style == (char *) (intptr_t) -1)
+ tty->TF_set_underline_style = NULL;
+#else
+ tty->TF_set_underline_style = tgetstr("Smulx", address);
+#endif
+ if (!tty->TF_set_underline_style && tgetflag("Su"))
+ tty->TF_set_underline_style = "\x1b[4:%p1%dm";
+
#else /* DOS_NT */
#ifdef WINDOWSNT
{
diff --git a/src/termchar.h b/src/termchar.h
index 5c47679a994..319c2319fba 100644
--- a/src/termchar.h
+++ b/src/termchar.h
@@ -171,6 +171,10 @@ #define EMACS_TERMCHAR_H
non-blank position. Must clear before writing _. */
int TF_teleray; /* termcap xt flag: many weird consequences.
For t1061. */
+ const char *TF_set_underline_style; /* termcap Smulx entry: Switches the underline
+ style based on the parameter. Param should
+ be one of: 0 (none), 1 (straight), 2 (double),
+ 3 (wave), 4 (dotted), or 5 (dashed). */
int RPov; /* # chars to start a TS_repeat */
diff --git a/src/xfaces.c b/src/xfaces.c
index cfbb89d2ae2..2c6c554d01d 100644
--- a/src/xfaces.c
+++ b/src/xfaces.c
@@ -5408,8 +5408,18 @@ tty_supports_face_attributes_p (struct frame *f,
{
if (STRINGP (val))
return false; /* ttys can't use colored underlines */
- else if (EQ (CAR_SAFE (val), QCstyle) && EQ (CAR_SAFE (CDR_SAFE (val)), Qwave))
- return false; /* ttys can't use wave underlines */
+ else if (EQ (CAR_SAFE (val), QCstyle))
+ {
+ if (!(EQ (CAR_SAFE (CDR_SAFE (val)), Qline) ||
+ EQ (CAR_SAFE (CDR_SAFE (val)), Qdouble) ||
+ EQ (CAR_SAFE (CDR_SAFE (val)), Qwave) ||
+ EQ (CAR_SAFE (CDR_SAFE (val)), Qdotted) ||
+ EQ (CAR_SAFE (CDR_SAFE (val)), Qdashed))) {
+ return false; /* Unsupported underline style */
+ }
+
+ test_caps |= TTY_CAP_UNDERLINE_STYLED;
+ }
else if (face_attr_equal_p (val, def_attrs[LFACE_UNDERLINE_INDEX]))
return false; /* same as default */
else
@@ -6335,6 +6345,8 @@ realize_gui_face (struct face_cache *cache, Lisp_Object attrs[LFACE_VECTOR_SIZE]
face->underline = FACE_UNDER_LINE;
else if (EQ (value, Qwave))
face->underline = FACE_UNDER_WAVE;
+ else
+ face->underline = FACE_UNDER_LINE;
}
else if (EQ (keyword, QCposition))
{
@@ -6469,6 +6481,7 @@ realize_tty_face (struct face_cache *cache,
{
struct face *face;
int weight, slant;
+ Lisp_Object underline;
bool face_colors_defaulted = false;
struct frame *f = cache->f;
@@ -6488,13 +6501,52 @@ realize_tty_face (struct face_cache *cache,
face->tty_bold_p = true;
if (slant != 100)
face->tty_italic_p = true;
- if (!NILP (attrs[LFACE_UNDERLINE_INDEX]))
- face->tty_underline_p = true;
if (!NILP (attrs[LFACE_INVERSE_INDEX]))
face->tty_reverse_p = true;
if (!NILP (attrs[LFACE_STRIKE_THROUGH_INDEX]))
face->tty_strike_through_p = true;
+ /* Text underline. */
+ underline = attrs[LFACE_UNDERLINE_INDEX];
+ if (NILP (underline)) {
+ face->tty_underline = FACE_NO_UNDERLINE;
+ } else if (EQ (underline, Qt)) {
+ face->tty_underline = FACE_UNDER_LINE;
+ } else if (STRINGP (underline)) {
+ face->tty_underline = FACE_UNDER_LINE;
+ } else if (CONSP (underline)) {
+ /* `(:style STYLE)'.
+ STYLE being one of `line', `double', `wave', `dotted' or `dashed'. */
+ face->tty_underline = FACE_UNDER_LINE;
+
+ while (CONSP (underline)) {
+ Lisp_Object keyword, value;
+
+ keyword = XCAR (underline);
+ underline = XCDR (underline);
+
+ if (!CONSP (underline))
+ break;
+ value = XCAR (underline);
+ underline = XCDR (underline);
+
+ if (EQ (keyword, QCstyle)) {
+ if (EQ (value, Qline))
+ face->tty_underline = FACE_UNDER_LINE;
+ else if (EQ (value, Qdouble))
+ face->tty_underline = FACE_DOUBLE_UNDER_LINE;
+ else if (EQ (value, Qwave))
+ face->tty_underline = FACE_UNDER_WAVE;
+ else if (EQ (value, Qdotted))
+ face->tty_underline = FACE_DOTTED_UNDER_LINE;
+ else if (EQ (value, Qdashed))
+ face->tty_underline = FACE_DASHED_UNDER_LINE;
+ else
+ face->tty_underline = FACE_UNDER_LINE;
+ }
+ }
+ }
+
/* Map color names to color indices. */
map_tty_color (f, face, LFACE_FOREGROUND_INDEX, &face_colors_defaulted);
map_tty_color (f, face, LFACE_BACKGROUND_INDEX, &face_colors_defaulted);
--
2.40.0
GNU bug tracking system
Copyright (C) 1999 Darren O. Benham,
1997,2003 nCipher Corporation Ltd,
1994-97 Ian Jackson.