Fix copy/paste shortcuts

https://st.suckless.org/patches/changealpha/

.gitignore

@@ -1,3 +1,4 @@
 st
 *.o
 *.orig
+.idea/

FAQ

@@ -2,12 +2,14 @@
 
 Use the excellent tool of [utmp](https://git.suckless.org/utmp/) for this task.
 
+
 ## Some _random program_ complains that st is unknown/not recognised/unsupported/whatever!
 
 It means that st doesn’t have any terminfo entry on your system. Chances are
 you did not `make install`. If you just want to test it without installing it,
 you can manually run `tic -sx st.info`.
 
+
 ## Nothing works, and nothing is said about an unknown terminal!
 
 * Some programs just assume they’re running in xterm i.e. they don’t rely on
@@ -15,6 +17,7 @@ you can manually run `tic -sx st.info`.
 * Some programs don’t complain about the lacking st description and default to
   another terminal. In that case see the question about terminfo.
 
+
 ## How do I scroll back up?
 
 * Using a terminal multiplexer.
@@ -23,10 +26,12 @@ you can manually run `tic -sx st.info`.
 * Using the excellent tool of [scroll](https://git.suckless.org/scroll/).
 * Using the scrollback [patch](https://st.suckless.org/patches/scrollback/).
 
+
 ## I would like to have utmp and/or scroll functionality by default
 
-You can add the absolute patch of both programs in your config.h
-file. You only have to modify the value of utmp and scroll variables.
+You can add the absolute path of both programs in your config.h file. You only
+have to modify the value of utmp and scroll variables.
+
 
 ## Why doesn't the Del key work in some programs?
 
@@ -83,12 +88,14 @@ If you are using zsh, then read the zsh FAQ
 
 Putting these lines into your .zshrc will fix the problems.
 
+
 ## How can I use meta in 8bit mode?
 
 St supports meta in 8bit mode, but the default terminfo entry doesn't
 use this capability. If you want it, you have to use the 'st-meta' value
 in TERM.
 
+
 ## I cannot compile st in OpenBSD
 
 OpenBSD lacks librt, despite it being mandatory in POSIX
@@ -97,6 +104,7 @@ If you want to compile st for OpenBSD you have to remove -lrt from config.mk, an
 st will compile without any loss of functionality, because all the functions are
 included in libc on this platform.
 
+
 ## The Backspace Case
 
 St is emulating the Linux way of handling backspace being delete and delete being
@@ -158,19 +166,60 @@ terminal users wants its backspace to be how he feels it:
 	[1] http://www.ibb.net/~anne/keyboard.html
 	[2] http://www.tldp.org/HOWTO/Keyboard-and-Console-HOWTO-5.html
 
+
 ## But I really want the old grumpy behaviour of my terminal
 
 Apply [1].
 
 [1] https://st.suckless.org/patches/delkey
 
-## Why do images not work in st (in programs such as w3m)?
 
-This is a terrible hack that overdraws an image on top of the terminal emulator
-window. It also relies on a very specific way the terminal draws it's contents.
+## Why do images not work in st using the w3m image hack?
+
+w3mimg uses a hack that draws an image on top of the terminal emulator Drawable
+window. The hack relies on the terminal to use a single buffer to draw its
+contents directly.
+
+st uses double-buffered drawing so the image is quickly replaced and may show a
+short flicker effect.
+
+Below is a patch example to change st double-buffering to a single Drawable
+buffer.
+
+diff --git a/x.c b/x.c
+--- a/x.c
++++ b/x.c
+@@ -732,10 +732,6 @@ xresize(int col, int row)
+ 	win.tw = col * win.cw;
+ 	win.th = row * win.ch;
+ 
+-	XFreePixmap(xw.dpy, xw.buf);
+-	xw.buf = XCreatePixmap(xw.dpy, xw.win, win.w, win.h,
+-			DefaultDepth(xw.dpy, xw.scr));
+-	XftDrawChange(xw.draw, xw.buf);
+ 	xclear(0, 0, win.w, win.h);
+ 
+ 	/* resize to new width */
+@@ -1148,8 +1144,7 @@ xinit(int cols, int rows)
+ 	gcvalues.graphics_exposures = False;
+ 	dc.gc = XCreateGC(xw.dpy, parent, GCGraphicsExposures,
+ 			&gcvalues);
+-	xw.buf = XCreatePixmap(xw.dpy, xw.win, win.w, win.h,
+-			DefaultDepth(xw.dpy, xw.scr));
++	xw.buf = xw.win;
+ 	XSetForeground(xw.dpy, dc.gc, dc.col[defaultbg].pixel);
+ 	XFillRectangle(xw.dpy, xw.buf, dc.gc, 0, 0, win.w, win.h);
+ 
+@@ -1632,8 +1627,6 @@ xdrawline(Line line, int x1, int y1, int x2)
+ void
+ xfinishdraw(void)
+ {
+-	XCopyArea(xw.dpy, xw.buf, xw.win, dc.gc, 0, 0, win.w,
+-			win.h, 0, 0);
+ 	XSetForeground(xw.dpy, dc.gc,
+ 			dc.col[IS_SET(MODE_REVERSE)?
+ 				defaultfg : defaultbg].pixel);
 
-A more proper (but limited way) would be using sixels. Which st doesn't
-support.
 
 ## BadLength X error in Xft when trying to render emoji
 

LICENSE

@@ -1,6 +1,6 @@
 MIT/X Consortium License
 
-© 2014-2018 Hiltjo Posthuma <hiltjo at codemadness dot org>
+© 2014-2022 Hiltjo Posthuma <hiltjo at codemadness dot org>
 © 2018 Devin J. Pohly <djpohly at gmail dot com>
 © 2014-2017 Quentin Rameau <quinq at fifth dot space>
 © 2009-2012 Aurélien APTEL <aurelien dot aptel at gmail dot com>

Makefile

@@ -4,7 +4,7 @@
 
 include config.mk
 
-SRC = st.c x.c
+SRC = st.c x.c boxdraw.c hb.c
 OBJ = $(SRC:.c=.o)
 
 all: options st
@@ -22,7 +22,9 @@ config.h:
 	$(CC) $(STCFLAGS) -c $<
 
 st.o: config.h st.h win.h
-x.o: arg.h config.h st.h win.h
+x.o: arg.h config.h st.h win.h hb.h
+hb.o: st.h
+boxdraw.o: config.h st.h boxdraw_data.h
 
 $(OBJ): config.h config.mk
 
@@ -50,9 +52,12 @@ install: st
 	chmod 644 $(DESTDIR)$(MANPREFIX)/man1/st.1
 	tic -sx st.info
 	@echo Please see the README file regarding the terminfo entry of st.
+	mkdir -p $(DESTDIR)$(PREFIX)/share/applications
+	cp -f st.desktop $(DESTDIR)$(PREFIX)/share/applications
 
 uninstall:
 	rm -f $(DESTDIR)$(PREFIX)/bin/st
 	rm -f $(DESTDIR)$(MANPREFIX)/man1/st.1
+	rm -f $(DESTDIR)$(PREFIX)/share/applications/st.desktop
 
 .PHONY: all options clean dist install uninstall

boxdraw.c

@@ -0,0 +1,194 @@
+/*
+ * Copyright 2018 Avi Halachmi (:avih) avihpit@yahoo.com https://github.com/avih
+ * MIT/X Consortium License
+ */
+
+#include <X11/Xft/Xft.h>
+#include "st.h"
+#include "boxdraw_data.h"
+
+/* Rounded non-negative integers division of n / d  */
+#define DIV(n, d) (((n) + (d) / 2) / (d))
+
+static Display *xdpy;
+static Colormap xcmap;
+static XftDraw *xd;
+static Visual *xvis;
+
+static void drawbox(int, int, int, int, XftColor *, XftColor *, ushort);
+static void drawboxlines(int, int, int, int, XftColor *, ushort);
+
+/* public API */
+
+void
+boxdraw_xinit(Display *dpy, Colormap cmap, XftDraw *draw, Visual *vis)
+{
+	xdpy = dpy; xcmap = cmap; xd = draw, xvis = vis;
+}
+
+int
+isboxdraw(Rune u)
+{
+	Rune block = u & ~0xff;
+	return (boxdraw && block == 0x2500 && boxdata[(uint8_t)u]) ||
+	       (boxdraw_braille && block == 0x2800);
+}
+
+/* the "index" is actually the entire shape data encoded as ushort */
+ushort
+boxdrawindex(const Glyph *g)
+{
+	if (boxdraw_braille && (g->u & ~0xff) == 0x2800)
+		return BRL | (uint8_t)g->u;
+	if (boxdraw_bold && (g->mode & ATTR_BOLD))
+		return BDB | boxdata[(uint8_t)g->u];
+	return boxdata[(uint8_t)g->u];
+}
+
+void
+drawboxes(int x, int y, int cw, int ch, XftColor *fg, XftColor *bg,
+          const XftGlyphFontSpec *specs, int len)
+{
+	for ( ; len-- > 0; x += cw, specs++)
+		drawbox(x, y, cw, ch, fg, bg, (ushort)specs->glyph);
+}
+
+/* implementation */
+
+void
+drawbox(int x, int y, int w, int h, XftColor *fg, XftColor *bg, ushort bd)
+{
+	ushort cat = bd & ~(BDB | 0xff);  /* mask out bold and data */
+	if (bd & (BDL | BDA)) {
+		/* lines (light/double/heavy/arcs) */
+		drawboxlines(x, y, w, h, fg, bd);
+
+	} else if (cat == BBD) {
+		/* lower (8-X)/8 block */
+		int d = DIV((uint8_t)bd * h, 8);
+		XftDrawRect(xd, fg, x, y + d, w, h - d);
+
+	} else if (cat == BBU) {
+		/* upper X/8 block */
+		XftDrawRect(xd, fg, x, y, w, DIV((uint8_t)bd * h, 8));
+
+	} else if (cat == BBL) {
+		/* left X/8 block */
+		XftDrawRect(xd, fg, x, y, DIV((uint8_t)bd * w, 8), h);
+
+	} else if (cat == BBR) {
+		/* right (8-X)/8 block */
+		int d = DIV((uint8_t)bd * w, 8);
+		XftDrawRect(xd, fg, x + d, y, w - d, h);
+
+	} else if (cat == BBQ) {
+		/* Quadrants */
+		int w2 = DIV(w, 2), h2 = DIV(h, 2);
+		if (bd & TL)
+			XftDrawRect(xd, fg, x, y, w2, h2);
+		if (bd & TR)
+			XftDrawRect(xd, fg, x + w2, y, w - w2, h2);
+		if (bd & BL)
+			XftDrawRect(xd, fg, x, y + h2, w2, h - h2);
+		if (bd & BR)
+			XftDrawRect(xd, fg, x + w2, y + h2, w - w2, h - h2);
+
+	} else if (bd & BBS) {
+		/* Shades - data is 1/2/3 for 25%/50%/75% alpha, respectively */
+		int d = (uint8_t)bd;
+		XftColor xfc;
+		XRenderColor xrc = { .alpha = 0xffff };
+
+		xrc.red = DIV(fg->color.red * d + bg->color.red * (4 - d), 4);
+		xrc.green = DIV(fg->color.green * d + bg->color.green * (4 - d), 4);
+		xrc.blue = DIV(fg->color.blue * d + bg->color.blue * (4 - d), 4);
+
+		XftColorAllocValue(xdpy, xvis, xcmap, &xrc, &xfc);
+		XftDrawRect(xd, &xfc, x, y, w, h);
+		XftColorFree(xdpy, xvis, xcmap, &xfc);
+
+	} else if (cat == BRL) {
+		/* braille, each data bit corresponds to one dot at 2x4 grid */
+		int w1 = DIV(w, 2);
+		int h1 = DIV(h, 4), h2 = DIV(h, 2), h3 = DIV(3 * h, 4);
+
+		if (bd & 1)   XftDrawRect(xd, fg, x, y, w1, h1);
+		if (bd & 2)   XftDrawRect(xd, fg, x, y + h1, w1, h2 - h1);
+		if (bd & 4)   XftDrawRect(xd, fg, x, y + h2, w1, h3 - h2);
+		if (bd & 8)   XftDrawRect(xd, fg, x + w1, y, w - w1, h1);
+		if (bd & 16)  XftDrawRect(xd, fg, x + w1, y + h1, w - w1, h2 - h1);
+		if (bd & 32)  XftDrawRect(xd, fg, x + w1, y + h2, w - w1, h3 - h2);
+		if (bd & 64)  XftDrawRect(xd, fg, x, y + h3, w1, h - h3);
+		if (bd & 128) XftDrawRect(xd, fg, x + w1, y + h3, w - w1, h - h3);
+
+	}
+}
+
+void
+drawboxlines(int x, int y, int w, int h, XftColor *fg, ushort bd)
+{
+	/* s: stem thickness. width/8 roughly matches underscore thickness. */
+	/* We draw bold as 1.5 * normal-stem and at least 1px thicker.      */
+	/* doubles draw at least 3px, even when w or h < 3. bold needs 6px. */
+	int mwh = MIN(w, h);
+	int base_s = MAX(1, DIV(mwh, 8));
+	int bold = (bd & BDB) && mwh >= 6;  /* possibly ignore boldness */
+	int s = bold ? MAX(base_s + 1, DIV(3 * base_s, 2)) : base_s;
+	int w2 = DIV(w - s, 2), h2 = DIV(h - s, 2);
+	/* the s-by-s square (x + w2, y + h2, s, s) is the center texel.    */
+	/* The base length (per direction till edge) includes this square.  */
+
+	int light = bd & (LL | LU | LR | LD);
+	int double_ = bd & (DL | DU | DR | DD);
+
+	if (light) {
+		/* d: additional (negative) length to not-draw the center   */
+		/* texel - at arcs and avoid drawing inside (some) doubles  */
+		int arc = bd & BDA;
+		int multi_light = light & (light - 1);
+		int multi_double = double_ & (double_ - 1);
+		/* light crosses double only at DH+LV, DV+LH (ref. shapes)  */
+		int d = arc || (multi_double && !multi_light) ? -s : 0;
+
+		if (bd & LL)
+			XftDrawRect(xd, fg, x, y + h2, w2 + s + d, s);
+		if (bd & LU)
+			XftDrawRect(xd, fg, x + w2, y, s, h2 + s + d);
+		if (bd & LR)
+			XftDrawRect(xd, fg, x + w2 - d, y + h2, w - w2 + d, s);
+		if (bd & LD)
+			XftDrawRect(xd, fg, x + w2, y + h2 - d, s, h - h2 + d);
+	}
+
+	/* double lines - also align with light to form heavy when combined */
+	if (double_) {
+		/*
+		* going clockwise, for each double-ray: p is additional length
+		* to the single-ray nearer to the previous direction, and n to
+		* the next. p and n adjust from the base length to lengths
+		* which consider other doubles - shorter to avoid intersections
+		* (p, n), or longer to draw the far-corner texel (n).
+		*/
+		int dl = bd & DL, du = bd & DU, dr = bd & DR, dd = bd & DD;
+		if (dl) {
+			int p = dd ? -s : 0, n = du ? -s : dd ? s : 0;
+			XftDrawRect(xd, fg, x, y + h2 + s, w2 + s + p, s);
+			XftDrawRect(xd, fg, x, y + h2 - s, w2 + s + n, s);
+		}
+		if (du) {
+			int p = dl ? -s : 0, n = dr ? -s : dl ? s : 0;
+			XftDrawRect(xd, fg, x + w2 - s, y, s, h2 + s + p);
+			XftDrawRect(xd, fg, x + w2 + s, y, s, h2 + s + n);
+		}
+		if (dr) {
+			int p = du ? -s : 0, n = dd ? -s : du ? s : 0;
+			XftDrawRect(xd, fg, x + w2 - p, y + h2 - s, w - w2 + p, s);
+			XftDrawRect(xd, fg, x + w2 - n, y + h2 + s, w - w2 + n, s);
+		}
+		if (dd) {
+			int p = dr ? -s : 0, n = dl ? -s : dr ? s : 0;
+			XftDrawRect(xd, fg, x + w2 + s, y + h2 - p, s, h - h2 + p);
+			XftDrawRect(xd, fg, x + w2 - s, y + h2 - n, s, h - h2 + n);
+		}
+	}
+}

boxdraw_data.h

@@ -0,0 +1,214 @@
+/*
+ * Copyright 2018 Avi Halachmi (:avih) avihpit@yahoo.com https://github.com/avih
+ * MIT/X Consortium License
+ */
+
+/*
+ * U+25XX codepoints data
+ *
+ * References:
+ *   http://www.unicode.org/charts/PDF/U2500.pdf
+ *   http://www.unicode.org/charts/PDF/U2580.pdf
+ *
+ * Test page:
+ *   https://github.com/GNOME/vte/blob/master/doc/boxes.txt
+ */
+
+/* Each shape is encoded as 16-bits. Higher bits are category, lower are data */
+/* Categories (mutually exclusive except BDB): */
+/* For convenience, BDL/BDA/BBS/BDB are 1 bit each, the rest are enums */
+#define BDL (1<<8)   /* Box Draw Lines (light/double/heavy) */
+#define BDA (1<<9)   /* Box Draw Arc (light) */
+
+#define BBD (1<<10)  /* Box Block Down (lower) X/8 */
+#define BBL (2<<10)  /* Box Block Left X/8 */
+#define BBU (3<<10)  /* Box Block Upper X/8 */
+#define BBR (4<<10)  /* Box Block Right X/8 */
+#define BBQ (5<<10)  /* Box Block Quadrants */
+#define BRL (6<<10)  /* Box Braille (data is lower byte of U28XX) */
+
+#define BBS (1<<14)  /* Box Block Shades */
+#define BDB (1<<15)  /* Box Draw is Bold */
+
+/* (BDL/BDA) Light/Double/Heavy x Left/Up/Right/Down/Horizontal/Vertical      */
+/* Heavy is light+double (literally drawing light+double align to form heavy) */
+#define LL (1<<0)
+#define LU (1<<1)
+#define LR (1<<2)
+#define LD (1<<3)
+#define LH (LL+LR)
+#define LV (LU+LD)
+
+#define DL (1<<4)
+#define DU (1<<5)
+#define DR (1<<6)
+#define DD (1<<7)
+#define DH (DL+DR)
+#define DV (DU+DD)
+
+#define HL (LL+DL)
+#define HU (LU+DU)
+#define HR (LR+DR)
+#define HD (LD+DD)
+#define HH (HL+HR)
+#define HV (HU+HD)
+
+/* (BBQ) Quadrants Top/Bottom x Left/Right */
+#define TL (1<<0)
+#define TR (1<<1)
+#define BL (1<<2)
+#define BR (1<<3)
+
+/* Data for U+2500 - U+259F except dashes/diagonals */
+static const unsigned short boxdata[256] = {
+	/* light lines */
+	[0x00] = BDL + LH,       /* light horizontal */
+	[0x02] = BDL + LV,       /* light vertical */
+	[0x0c] = BDL + LD + LR,  /* light down and right */
+	[0x10] = BDL + LD + LL,  /* light down and left */
+	[0x14] = BDL + LU + LR,  /* light up and right */
+	[0x18] = BDL + LU + LL,  /* light up and left */
+	[0x1c] = BDL + LV + LR,  /* light vertical and right */
+	[0x24] = BDL + LV + LL,  /* light vertical and left */
+	[0x2c] = BDL + LH + LD,  /* light horizontal and down */
+	[0x34] = BDL + LH + LU,  /* light horizontal and up */
+	[0x3c] = BDL + LV + LH,  /* light vertical and horizontal */
+	[0x74] = BDL + LL,       /* light left */
+	[0x75] = BDL + LU,       /* light up */
+	[0x76] = BDL + LR,       /* light right */
+	[0x77] = BDL + LD,       /* light down */
+
+	/* heavy [+light] lines */
+	[0x01] = BDL + HH,
+	[0x03] = BDL + HV,
+	[0x0d] = BDL + HR + LD,
+	[0x0e] = BDL + HD + LR,
+	[0x0f] = BDL + HD + HR,
+	[0x11] = BDL + HL + LD,
+	[0x12] = BDL + HD + LL,
+	[0x13] = BDL + HD + HL,
+	[0x15] = BDL + HR + LU,
+	[0x16] = BDL + HU + LR,
+	[0x17] = BDL + HU + HR,
+	[0x19] = BDL + HL + LU,
+	[0x1a] = BDL + HU + LL,
+	[0x1b] = BDL + HU + HL,
+	[0x1d] = BDL + HR + LV,
+	[0x1e] = BDL + HU + LD + LR,
+	[0x1f] = BDL + HD + LR + LU,
+	[0x20] = BDL + HV + LR,
+	[0x21] = BDL + HU + HR + LD,
+	[0x22] = BDL + HD + HR + LU,
+	[0x23] = BDL + HV + HR,
+	[0x25] = BDL + HL + LV,
+	[0x26] = BDL + HU + LD + LL,
+	[0x27] = BDL + HD + LU + LL,
+	[0x28] = BDL + HV + LL,
+	[0x29] = BDL + HU + HL + LD,
+	[0x2a] = BDL + HD + HL + LU,
+	[0x2b] = BDL + HV + HL,
+	[0x2d] = BDL + HL + LD + LR,
+	[0x2e] = BDL + HR + LL + LD,
+	[0x2f] = BDL + HH + LD,
+	[0x30] = BDL + HD + LH,
+	[0x31] = BDL + HD + HL + LR,
+	[0x32] = BDL + HR + HD + LL,
+	[0x33] = BDL + HH + HD,
+	[0x35] = BDL + HL + LU + LR,
+	[0x36] = BDL + HR + LU + LL,
+	[0x37] = BDL + HH + LU,
+	[0x38] = BDL + HU + LH,
+	[0x39] = BDL + HU + HL + LR,
+	[0x3a] = BDL + HU + HR + LL,
+	[0x3b] = BDL + HH + HU,
+	[0x3d] = BDL + HL + LV + LR,
+	[0x3e] = BDL + HR + LV + LL,
+	[0x3f] = BDL + HH + LV,
+	[0x40] = BDL + HU + LH + LD,
+	[0x41] = BDL + HD + LH + LU,
+	[0x42] = BDL + HV + LH,
+	[0x43] = BDL + HU + HL + LD + LR,
+	[0x44] = BDL + HU + HR + LD + LL,
+	[0x45] = BDL + HD + HL + LU + LR,
+	[0x46] = BDL + HD + HR + LU + LL,
+	[0x47] = BDL + HH + HU + LD,
+	[0x48] = BDL + HH + HD + LU,
+	[0x49] = BDL + HV + HL + LR,
+	[0x4a] = BDL + HV + HR + LL,
+	[0x4b] = BDL + HV + HH,
+	[0x78] = BDL + HL,
+	[0x79] = BDL + HU,
+	[0x7a] = BDL + HR,
+	[0x7b] = BDL + HD,
+	[0x7c] = BDL + HR + LL,
+	[0x7d] = BDL + HD + LU,
+	[0x7e] = BDL + HL + LR,
+	[0x7f] = BDL + HU + LD,
+
+	/* double [+light] lines */
+	[0x50] = BDL + DH,
+	[0x51] = BDL + DV,
+	[0x52] = BDL + DR + LD,
+	[0x53] = BDL + DD + LR,
+	[0x54] = BDL + DR + DD,
+	[0x55] = BDL + DL + LD,
+	[0x56] = BDL + DD + LL,
+	[0x57] = BDL + DL + DD,
+	[0x58] = BDL + DR + LU,
+	[0x59] = BDL + DU + LR,
+	[0x5a] = BDL + DU + DR,
+	[0x5b] = BDL + DL + LU,
+	[0x5c] = BDL + DU + LL,
+	[0x5d] = BDL + DL + DU,
+	[0x5e] = BDL + DR + LV,
+	[0x5f] = BDL + DV + LR,
+	[0x60] = BDL + DV + DR,
+	[0x61] = BDL + DL + LV,
+	[0x62] = BDL + DV + LL,
+	[0x63] = BDL + DV + DL,
+	[0x64] = BDL + DH + LD,
+	[0x65] = BDL + DD + LH,
+	[0x66] = BDL + DD + DH,
+	[0x67] = BDL + DH + LU,
+	[0x68] = BDL + DU + LH,
+	[0x69] = BDL + DH + DU,
+	[0x6a] = BDL + DH + LV,
+	[0x6b] = BDL + DV + LH,
+	[0x6c] = BDL + DH + DV,
+
+	/* (light) arcs */
+	[0x6d] = BDA + LD + LR,
+	[0x6e] = BDA + LD + LL,
+	[0x6f] = BDA + LU + LL,
+	[0x70] = BDA + LU + LR,
+
+	/* Lower (Down) X/8 block (data is 8 - X) */
+	[0x81] = BBD + 7, [0x82] = BBD + 6, [0x83] = BBD + 5, [0x84] = BBD + 4,
+	[0x85] = BBD + 3, [0x86] = BBD + 2, [0x87] = BBD + 1, [0x88] = BBD + 0,
+
+	/* Left X/8 block (data is X) */
+	[0x89] = BBL + 7, [0x8a] = BBL + 6, [0x8b] = BBL + 5, [0x8c] = BBL + 4,
+	[0x8d] = BBL + 3, [0x8e] = BBL + 2, [0x8f] = BBL + 1,
+
+	/* upper 1/2 (4/8), 1/8 block (X), right 1/2, 1/8 block (8-X) */
+	[0x80] = BBU + 4, [0x94] = BBU + 1,
+	[0x90] = BBR + 4, [0x95] = BBR + 7,
+
+	/* Quadrants */
+	[0x96] = BBQ + BL,
+	[0x97] = BBQ + BR,
+	[0x98] = BBQ + TL,
+	[0x99] = BBQ + TL + BL + BR,
+	[0x9a] = BBQ + TL + BR,
+	[0x9b] = BBQ + TL + TR + BL,
+	[0x9c] = BBQ + TL + TR + BR,
+	[0x9d] = BBQ + TR,
+	[0x9e] = BBQ + BL + TR,
+	[0x9f] = BBQ + BL + TR + BR,
+
+	/* Shades, data is an alpha value in 25% units (1/4, 1/2, 3/4) */
+	[0x91] = BBS + 1, [0x92] = BBS + 2, [0x93] = BBS + 3,
+
+	/* U+2504 - U+250B, U+254C - U+254F: unsupported (dashes) */
+	/* U+2571 - U+2573: unsupported (diagonals) */
+};

config.def.h

@@ -43,9 +43,18 @@ static unsigned int tripleclicktimeout = 600;
 /* alt screens */
 int allowaltscreen = 1;
 
-/* frames per second st should at maximum draw to the screen */
-static unsigned int xfps = 120;
-static unsigned int actionfps = 30;
+/* allow certain non-interactive (insecure) window operations such as:
+   setting the clipboard text */
+int allowwindowops = 0;
+
+/*
+ * draw latency range in ms - from new content/keypress/etc until drawing.
+ * within this range, st draws when content stops arriving (idle). mostly it's
+ * near minlatency, but it waits longer for slow updates to avoid partial draw.
+ * low minlatency will tear/flicker more, as it can "detect" idle too early.
+ */
+static double minlatency = 8;
+static double maxlatency = 33;
 
 /*
  * blinking timeout (set to 0 to disable blinking) for the terminal blinking
@@ -58,6 +67,18 @@ static unsigned int blinktimeout = 800;
  */
 static unsigned int cursorthickness = 2;
 
+/*
+ * 1: render most of the lines/blocks characters without using the font for
+ *    perfect alignment between cells (U2500 - U259F except dashes/diagonals).
+ *    Bold affects lines thickness if boxdraw_bold is not 0. Italic is ignored.
+ * 0: disable (render all U25XX glyphs normally from the font).
+ */
+const int boxdraw = 0;
+const int boxdraw_bold = 0;
+
+/* braille (U28XX):  1: render as adjacent "pixels",  0: use font */
+const int boxdraw_braille = 0;
+
 /*
  * bell volume. It must be a value between -100 and 100. Use 0 for disabling
  * it
@@ -86,31 +107,48 @@ unsigned int tabspaces = 8;
 
 /* bg opacity */
 float alpha = 0.8;
+float alpha_def;
 
-/* Terminal colors (16 used in escape sequence) */
-static const char *palettes[][16] = {
-    {"black", "red3", "green3", "yellow3", "blue2", "magenta3", "cyan3", "gray90",
-    "gray50", "red", "green", "yellow", "#5c5cff", "magenta", "cyan", "white"},
-    {"#223", "#900", "#080", "#fe7", "#35e", "#fc5", "#18e", "#aaa",
-    "#666", "#f25", "#0b0", "#ff6", "#46f", "#d6a", "#6bf", "#ddd"},
-    {"#eaeaea", "#b7141f", "#457b24", "#fc7b08", "#134eb2", "#560088", "#0e717c", "#777777",
-    "#424242", "#e83b3f", "#7aba3a", "#fd8e09", "#54a4f3", "#aa4dbc", "#26bbd1", "#aaaaaa"},
-    {"#20242d", "#b04b57", "#87b379", "#e5c179", "#7d8fa4", "#a47996", "#85a7a5", "#b3b8c3",
-    "#000000", "#b04b57", "#87b379", "#e5c179", "#7d8fa4", "#a47996", "#85a7a5", "#ffffff"},
+/* Terminal colors (16 first used in escape sequence) */
+static const char *colorname[] = {
+	/* 8 normal colors */
 	"black",
-};
+	"red3",
+	"green3",
+	"yellow3",
+	"blue2",
+	"magenta3",
+	"cyan3",
+	"gray90",
 
-static const char **colorname;
+	/* 8 bright colors */
+	"gray50",
+	"red",
+	"green",
+	"yellow",
+	"#5c5cff",
+	"magenta",
+	"cyan",
+	"white",
+
+	[255] = 0,
+
+	/* more colors can be added after 255 to use with DefaultXX */
+	"#cccccc",
+	"#555555",
+	"gray90", /* default foreground colour */
+	"black", /* default background colour */
+};
 
 
 /*
  * Default colors (colorname index)
  * foreground, background, cursor, reverse cursor
  */
-unsigned int defaultfg = 5;
-unsigned int defaultbg = 258;
-static unsigned int defaultcs = 5;
-static unsigned int defaultrcs = 5;
+unsigned int defaultfg = 258;
+unsigned int defaultbg = 259;
+unsigned int defaultcs = 256;
+static unsigned int defaultrcs = 257;
 
 /*
  * Default shape of cursor
@@ -155,7 +193,9 @@ static uint forcemousemod = ShiftMask;
 static MouseShortcut mshortcuts[] = {
 	/* mask                 button   function        argument       release */
 	{ XK_ANY_MOD,           Button2, selpaste,       {.i = 0},      1 },
+	{ ShiftMask,            Button4, ttysend,        {.s = "\033[5;2~"} },
 	{ XK_ANY_MOD,           Button4, ttysend,        {.s = "\031"} },
+	{ ShiftMask,            Button5, ttysend,        {.s = "\033[6;2~"} },
 	{ XK_ANY_MOD,           Button5, ttysend,        {.s = "\005"} },
 };
 
@@ -179,15 +219,9 @@ static Shortcut shortcuts[] = {
 	{ ShiftMask,            XK_Page_Down,   kscrolldown,    {.i = -1} },
 	{ ShiftMask,            XK_Insert,      selpaste,       {.i =  0} },
 	{ TERMMOD,              XK_Num_Lock,    numlock,        {.i =  0} },
-    { MODKEY|ShiftMask,     XK_F1,          setpalette,     {.i =  0} },
-    { MODKEY|ShiftMask,     XK_F2,          setpalette,     {.i =  1} },
-    { MODKEY|ShiftMask,     XK_F3,          setpalette,     {.i =  2} },
-    { MODKEY|ShiftMask,     XK_F4,          setpalette,     {.i =  3} },
-    { MODKEY|ShiftMask,     XK_F5,          setpalette,     {.i =  4} },
-    { MODKEY|ShiftMask,     XK_F6,          setpalette,     {.i =  5} },
-    { MODKEY|ShiftMask,     XK_F7,          setpalette,     {.i =  6} },
-    { MODKEY|ShiftMask,     XK_F8,          setpalette,     {.i =  7} },
-    { MODKEY|ShiftMask,     XK_F9,          setpalette,     {.i =  8} },
+	{ MODKEY,               XK_bracketleft, chgalpha,       {.f = -1} }, /* Decrease opacity */
+	{ MODKEY|ShiftMask,     XK_braceright,  chgalpha,       {.f = +1} }, /* Increase opacity */
+	{ MODKEY,               XK_bracketright,chgalpha,       {.f =  0} }, /* Reset opacity */
 };
 
 /*

config.h

@@ -5,7 +5,7 @@
  *
  * font: see http://freedesktop.org/software/fontconfig/fontconfig-user.html
  */
-static char *font = "Liberation Mono:pixelsize=18:antialias=true:autohint=true";
+static char *font = "FiraCode:pixelsize=18:antialias=true:autohint=true";
 static int borderpx = 0;
 
 /*
@@ -43,6 +43,20 @@ static unsigned int tripleclicktimeout = 600;
 /* alt screens */
 int allowaltscreen = 1;
 
+/* allow certain non-interactive (insecure) window operations such as:
+   setting the clipboard text */
+int allowwindowops = 0;
+
+/*
+ * draw latency range in ms - from new content/keypress/etc until drawing.
+ * within this range, st draws when content stops arriving (idle). mostly it's
+ * near minlatency, but it waits longer for slow updates to avoid partial draw.
+ * low minlatency will tear/flicker more, as it can "detect" idle too early.
+ */
+static double minlatency = 8;
+static double maxlatency = 33;
+
+
 /* frames per second st should at maximum draw to the screen */
 static unsigned int xfps = 120;
 static unsigned int actionfps = 30;
@@ -58,6 +72,18 @@ static unsigned int blinktimeout = 800;
  */
 static unsigned int cursorthickness = 2;
 
+/*
+ * 1: render most of the lines/blocks characters without using the font for
+ *    perfect alignment between cells (U2500 - U259F except dashes/diagonals).
+ *    Bold affects lines thickness if boxdraw_bold is not 0. Italic is ignored.
+ * 0: disable (render all U25XX glyphs normally from the font).
+ */
+const int boxdraw = 1;
+const int boxdraw_bold = 0;
+
+/* braille (U28XX):  1: render as adjacent "pixels",  0: use font */
+const int boxdraw_braille = 0;
+
 /*
  * bell volume. It must be a value between -100 and 100. Use 0 for disabling
  * it
@@ -85,30 +111,47 @@ char *termname = "st-256color";
 unsigned int tabspaces = 8;
 
 /* bg opacity */
-float alpha = 0.7;
+float alpha = 0.85;
+float alpha_def;
 
-/* Terminal colors (16 used in escape sequence) */
-static const char *palettes[][16] = {
-        {"black", "red3", "green3", "yellow3", "blue2", "magenta3", "cyan3", "gray90",
-         "gray50", "red", "green", "yellow", "#5c5cff", "magenta", "cyan", "white"},
-        {"#223", "#900", "#080", "#fe7", "#35e", "#fc5", "#18e", "#aaa",
-         "#666", "#f25", "#0b0", "#ff6", "#46f", "#d6a", "#6bf", "#ddd"},
-        {"#eaeaea", "#b7141f", "#457b24", "#fc7b08", "#134eb2", "#560088", "#0e717c", "#777777",
-         "#424242", "#e83b3f", "#7aba3a", "#fd8e09", "#54a4f3", "#aa4dbc", "#26bbd1", "#aaaaaa"},
-        {"#20242d", "#b04b57", "#87b379", "#e5c179", "#7d8fa4", "#a47996", "#85a7a5", "#b3b8c3",
-         "#000000", "#b04b57", "#87b379", "#e5c179", "#7d8fa4", "#a47996", "#85a7a5", "#ffffff"},
+/* Terminal colors (16 first used in escape sequence) */
+static const char *colorname[] = {
+	/* 8 normal colors */
+	"black",
+	"red3",
+	"green3",
+	"yellow3",
+	"blue2",
+	"magenta3",
+	"cyan3",
+	"gray90",
+
+	/* 8 bright colors */
+	"gray50",
+	"red",
+	"green",
+	"yellow",
+	"#5c5cff",
+	"magenta",
+	"cyan",
+	"white",
+
+	[255] = 0,
+
+	/* more colors can be added after 255 to use with DefaultXX */
+	"#cccccc",
+	"#555555",
 };
 
-static const char **colorname;
 
 /*
  * Default colors (colorname index)
  * foreground, background, cursor, reverse cursor
  */
-unsigned int defaultfg = 1;
+unsigned int defaultfg = 7;
 unsigned int defaultbg = 0;
-static unsigned int defaultcs = 1;
-static unsigned int defaultrcs = 1;
+unsigned int defaultcs = 256;
+static unsigned int defaultrcs = 257;
 
 /*
  * Default shape of cursor
@@ -164,30 +207,24 @@ static MouseShortcut mshortcuts[] = {
 #define TERMMOD (ControlMask|ShiftMask)
 
 static Shortcut shortcuts[] = {
-        /* mask                 keysym          function        argument */
-        {XK_ANY_MOD,  XK_Break,     sendbreak,     {.i =  0}},
-        {ControlMask, XK_Print,     toggleprinter, {.i =  0}},
-        {ShiftMask,   XK_Print,     printscreen,   {.i =  0}},
-        {XK_ANY_MOD,  XK_Print,     printsel,      {.i =  0}},
-        {TERMMOD,     XK_Prior,     zoom,          {.f = +1}},
-        {TERMMOD,     XK_Next,      zoom,          {.f = -1}},
-        {TERMMOD,     XK_Home,      zoomreset,     {.f =  0}},
-        {TERMMOD,     XK_C,         clipcopy,      {.i =  0}},
-        {TERMMOD,     XK_V,         clippaste,     {.i =  0}},
-        {TERMMOD,     XK_Y,         selpaste,      {.i =  0}},
-        {ShiftMask,   XK_Page_Up,   kscrollup,     {.i = -1}},
-        {ShiftMask,   XK_Page_Down, kscrolldown,   {.i = -1}},
-        {ShiftMask,   XK_Insert,    selpaste,      {.i =  0}},
-        {TERMMOD,     XK_Num_Lock,  numlock,       {.i =  0}},
-        {MODKEY | ShiftMask, XK_F1, setpalette, {.i =  0}},
-        {MODKEY | ShiftMask, XK_F2, setpalette, {.i =  1}},
-        {MODKEY | ShiftMask, XK_F3, setpalette, {.i =  2}},
-        {MODKEY | ShiftMask, XK_F4, setpalette, {.i =  3}},
-        {MODKEY | ShiftMask, XK_F5, setpalette, {.i =  4}},
-        {MODKEY | ShiftMask, XK_F6, setpalette, {.i =  5}},
-        {MODKEY | ShiftMask, XK_F7, setpalette, {.i =  6}},
-        {MODKEY | ShiftMask, XK_F8, setpalette, {.i =  7}},
-        {MODKEY | ShiftMask, XK_F9, setpalette, {.i =  8}},
+	/* mask                 keysym          function        argument */
+	{ XK_ANY_MOD,           XK_Break,       sendbreak,      {.i =  0} },
+	{ ControlMask,          XK_Print,       toggleprinter,  {.i =  0} },
+	{ ShiftMask,            XK_Print,       printscreen,    {.i =  0} },
+	{ XK_ANY_MOD,           XK_Print,       printsel,       {.i =  0} },
+	{ MODKEY,               XK_Prior,       zoom,           {.f = +1} },
+	{ MODKEY,               XK_Next,        zoom,           {.f = -1} },
+	{ MODKEY,               XK_Home,        zoomreset,      {.f =  0} },
+	{ TERMMOD,              XK_C,           clipcopy,       {.i =  0} },
+	{ TERMMOD,              XK_V,           clippaste,      {.i =  0} },
+	{ TERMMOD,              XK_Y,           selpaste,       {.i =  0} },
+    { ShiftMask,            XK_Page_Up,     kscrollup,      {.i = -1} },
+    { ShiftMask,            XK_Page_Down,   kscrolldown,    {.i = -1} },
+	{ ShiftMask,            XK_Insert,      selpaste,       {.i =  0} },
+	{ MODKEY,               XK_Num_Lock,    numlock,        {.i =  0} },
+    { MODKEY,               XK_bracketleft, chgalpha,       {.f = -1} }, /* Decrease opacity */
+	{ MODKEY|ShiftMask,     XK_braceright,  chgalpha,       {.f = +1} }, /* Increase opacity */
+	{ MODKEY,               XK_bracketright,chgalpha,       {.f =  0} }, /* Reset opacity */
 };
 
 /*

config.mk

@@ -1,10 +1,10 @@
 # st version
-VERSION = 0.8.3
+VERSION = 0.8.5
 
 # Customize below to fit your system
 
 # paths
-PREFIX = $(HOME)
+PREFIX = /usr/local
 MANPREFIX = $(PREFIX)/share/man
 
 X11INC = /usr/X11R6/include
@@ -15,21 +15,24 @@ PKG_CONFIG = pkg-config
 # includes and libs
 INCS = -I$(X11INC) \
        `$(PKG_CONFIG) --cflags fontconfig` \
-       `$(PKG_CONFIG) --cflags freetype2`
+       `$(PKG_CONFIG) --cflags freetype2` \
+       `$(PKG_CONFIG) --cflags harfbuzz`
 LIBS = -L$(X11LIB) -lm -lrt -lX11 -lutil -lXft -lXrender\
        `$(PKG_CONFIG) --libs fontconfig` \
-       `$(PKG_CONFIG) --libs freetype2`
+       `$(PKG_CONFIG) --libs freetype2` \
+       `$(PKG_CONFIG) --libs harfbuzz`
 
 # flags
 STCPPFLAGS = -DVERSION=\"$(VERSION)\" -D_XOPEN_SOURCE=600
-STCFLAGS = $(INCS) $(STCPPFLAGS) $(CPPFLAGS) $(CFLAGS) -ggdb
+STCFLAGS = $(INCS) $(STCPPFLAGS) $(CPPFLAGS) $(CFLAGS)
 STLDFLAGS = $(LIBS) $(LDFLAGS)
 
 # OpenBSD:
 #CPPFLAGS = -DVERSION=\"$(VERSION)\" -D_XOPEN_SOURCE=600 -D_BSD_SOURCE
 #LIBS = -L$(X11LIB) -lm -lX11 -lutil -lXft \
-#       `pkg-config --libs fontconfig` \
-#       `pkg-config --libs freetype2`
+#       `$(PKG_CONFIG) --libs fontconfig` \
+#       `$(PKG_CONFIG) --libs freetype2`
+#MANPREFIX = ${PREFIX}/man
 
 # compiler and linker
 # CC = c99

hb.c

@@ -0,0 +1,148 @@
+#include <stdlib.h>
+#include <stdio.h>
+#include <math.h>
+#include <X11/Xft/Xft.h>
+#include <hb.h>
+#include <hb-ft.h>
+
+#include "st.h"
+
+#define FEATURE(c1,c2,c3,c4) { .tag = HB_TAG(c1,c2,c3,c4), .value = 1, .start = HB_FEATURE_GLOBAL_START, .end = HB_FEATURE_GLOBAL_END }
+
+void hbtransformsegment(XftFont *xfont, const Glyph *string, hb_codepoint_t *codepoints, int start, int length);
+hb_font_t *hbfindfont(XftFont *match);
+
+typedef struct {
+	XftFont *match;
+	hb_font_t *font;
+} HbFontMatch;
+
+static int hbfontslen = 0;
+static HbFontMatch *hbfontcache = NULL;
+
+/*
+ * Replace 0 with a list of font features, wrapped in FEATURE macro, e.g.
+ * FEATURE('c', 'a', 'l', 't'), FEATURE('d', 'l', 'i', 'g')
+ */
+hb_feature_t features[] = { 0 };
+
+void
+hbunloadfonts()
+{
+	for (int i = 0; i < hbfontslen; i++) {
+		hb_font_destroy(hbfontcache[i].font);
+		XftUnlockFace(hbfontcache[i].match);
+	}
+
+	if (hbfontcache != NULL) {
+		free(hbfontcache);
+		hbfontcache = NULL;
+	}
+	hbfontslen = 0;
+}
+
+hb_font_t *
+hbfindfont(XftFont *match)
+{
+	for (int i = 0; i < hbfontslen; i++) {
+		if (hbfontcache[i].match == match)
+			return hbfontcache[i].font;
+	}
+
+	/* Font not found in cache, caching it now. */
+	hbfontcache = realloc(hbfontcache, sizeof(HbFontMatch) * (hbfontslen + 1));
+	FT_Face face = XftLockFace(match);
+	hb_font_t *font = hb_ft_font_create(face, NULL);
+	if (font == NULL)
+		die("Failed to load Harfbuzz font.");
+
+	hbfontcache[hbfontslen].match = match;
+	hbfontcache[hbfontslen].font = font;
+	hbfontslen += 1;
+
+	return font;
+}
+
+void
+hbtransform(XftGlyphFontSpec *specs, const Glyph *glyphs, size_t len, int x, int y)
+{
+	int start = 0, length = 1, gstart = 0;
+	hb_codepoint_t *codepoints = calloc((unsigned int)len, sizeof(hb_codepoint_t));
+
+	for (int idx = 1, specidx = 1; idx < len; idx++) {
+		if (glyphs[idx].mode & ATTR_WDUMMY) {
+			length += 1;
+			continue;
+		}
+
+		if (specs[specidx].font != specs[start].font || ATTRCMP(glyphs[gstart], glyphs[idx]) || selected(x + idx, y) != selected(x + gstart, y)) {
+			hbtransformsegment(specs[start].font, glyphs, codepoints, gstart, length);
+
+			/* Reset the sequence. */
+			length = 1;
+			start = specidx;
+			gstart = idx;
+		} else {
+			length += 1;
+		}
+
+		specidx++;
+	}
+
+	/* EOL. */
+	hbtransformsegment(specs[start].font, glyphs, codepoints, gstart, length);
+
+	/* Apply the transformation to glyph specs. */
+	for (int i = 0, specidx = 0; i < len; i++) {
+		if (glyphs[i].mode & ATTR_WDUMMY)
+			continue;
+		if (glyphs[i].mode & ATTR_BOXDRAW) {
+			specidx++;
+			continue;
+		}
+
+		if (codepoints[i] != specs[specidx].glyph)
+			((Glyph *)glyphs)[i].mode |= ATTR_LIGA;
+
+		specs[specidx++].glyph = codepoints[i];
+	}
+
+	free(codepoints);
+}
+
+void
+hbtransformsegment(XftFont *xfont, const Glyph *string, hb_codepoint_t *codepoints, int start, int length)
+{
+	hb_font_t *font = hbfindfont(xfont);
+	if (font == NULL)
+		return;
+
+	Rune rune;
+	ushort mode = USHRT_MAX;
+	hb_buffer_t *buffer = hb_buffer_create();
+	hb_buffer_set_direction(buffer, HB_DIRECTION_LTR);
+
+	/* Fill buffer with codepoints. */
+	for (int i = start; i < (start+length); i++) {
+		rune = string[i].u;
+		mode = string[i].mode;
+		if (mode & ATTR_WDUMMY)
+			rune = 0x0020;
+		hb_buffer_add_codepoints(buffer, &rune, 1, 0, 1);
+	}
+
+	/* Shape the segment. */
+	hb_shape(font, buffer, features, sizeof(features));
+
+	/* Get new glyph info. */
+	hb_glyph_info_t *info = hb_buffer_get_glyph_infos(buffer, NULL);
+
+	/* Write new codepoints. */
+	for (int i = 0; i < length; i++) {
+		hb_codepoint_t gid = info[i].codepoint;
+		codepoints[start+i] = gid;
+	}
+
+	/* Cleanup. */
+	hb_buffer_destroy(buffer);
+}

hb.h

@@ -0,0 +1,6 @@
+#include <X11/Xft/Xft.h>
+#include <hb.h>
+#include <hb-ft.h>
+
+void hbunloadfonts();
+void hbtransform(XftGlyphFontSpec *, const Glyph *, size_t, int, int);

patches/st-alpha-changealpha-20230519-b44f2ad.diff

@@ -0,0 +1,194 @@
+diff --git a/st/config.def.h b/st_patched/config.def.h
+index 91ab8ca..59fc2a9 100644
+--- a/config.def.h
++++ b/config.def.h
+@@ -93,6 +93,10 @@ char *termname = "st-256color";
+  */
+ unsigned int tabspaces = 8;
+ 
++/* bg opacity */
++float alpha = 0.8;
++float alpha_def;
++
+ /* Terminal colors (16 first used in escape sequence) */
+ static const char *colorname[] = {
+ 	/* 8 normal colors */
+@@ -201,6 +205,9 @@ static Shortcut shortcuts[] = {
+ 	{ TERMMOD,              XK_Y,           selpaste,       {.i =  0} },
+ 	{ ShiftMask,            XK_Insert,      selpaste,       {.i =  0} },
+ 	{ TERMMOD,              XK_Num_Lock,    numlock,        {.i =  0} },
++	{ MODKEY,               XK_bracketleft, chgalpha,       {.f = -1} }, /* Decrease opacity */
++	{ MODKEY|ShiftMask,     XK_braceright,  chgalpha,       {.f = +1} }, /* Increase opacity */
++	{ MODKEY,               XK_bracketright,chgalpha,       {.f =  0} }, /* Reset opacity */
+ };
+ 
+ /*
+diff --git a/st/st.h b/st_patched/st.h
+index fd3b0d8..cda8c13 100644
+--- a/st.h
++++ b/st.h
+@@ -124,3 +124,4 @@ extern unsigned int tabspaces;
+ extern unsigned int defaultfg;
+ extern unsigned int defaultbg;
+ extern unsigned int defaultcs;
++extern float alpha, alpha_def;
+diff --git a/st/config.mk b/st_patched/config.mk
+index 1e306f8..47c615e 100644
+--- a/config.mk
++++ b/config.mk
+@@ -16,7 +16,7 @@ PKG_CONFIG = pkg-config
+ INCS = -I$(X11INC) \
+        `$(PKG_CONFIG) --cflags fontconfig` \
+        `$(PKG_CONFIG) --cflags freetype2`
+-LIBS = -L$(X11LIB) -lm -lrt -lX11 -lutil -lXft \
++LIBS = -L$(X11LIB) -lm -lrt -lX11 -lutil -lXft -lXrender\
+        `$(PKG_CONFIG) --libs fontconfig` \
+        `$(PKG_CONFIG) --libs freetype2`
+ 
+diff --git a/st/x.c b/st_patched/x.c
+index aa09997..3b05a55 100644
+--- a/x.c
++++ b/x.c
+@@ -59,6 +59,7 @@ static void zoom(const Arg *);
+ static void zoomabs(const Arg *);
+ static void zoomreset(const Arg *);
+ static void ttysend(const Arg *);
++static void chgalpha(const Arg *);
+ 
+ /* config.h for applying patches and the configuration. */
+ #include "config.h"
+@@ -105,6 +106,7 @@ typedef struct {
+ 	XSetWindowAttributes attrs;
+ 	int scr;
+ 	int isfixed; /* is fixed geometry? */
++	int depth; /* bit depth */
+ 	int l, t; /* left and top offset */
+ 	int gm; /* geometry mask */
+ } XWindow;
+@@ -243,6 +245,7 @@ static char *usedfont = NULL;
+ static double usedfontsize = 0;
+ static double defaultfontsize = 0;
+ 
++static char *opt_alpha = NULL;
+ static char *opt_class = NULL;
+ static char **opt_cmd  = NULL;
+ static char *opt_embed = NULL;
+@@ -752,7 +755,7 @@ xresize(int col, int row)
+ 
+ 	XFreePixmap(xw.dpy, xw.buf);
+ 	xw.buf = XCreatePixmap(xw.dpy, xw.win, win.w, win.h,
+-			DefaultDepth(xw.dpy, xw.scr));
++			xw.depth);
+ 	XftDrawChange(xw.draw, xw.buf);
+ 	xclear(0, 0, win.w, win.h);
+ 
+@@ -812,6 +815,13 @@ xloadcols(void)
+ 			else
+ 				die("could not allocate color %d\n", i);
+ 		}
++
++	/* set alpha value of bg color */
++	if (opt_alpha)
++		alpha = strtof(opt_alpha, NULL);
++	dc.col[defaultbg].color.alpha = (unsigned short)(0xffff * alpha);
++	dc.col[defaultbg].pixel &= 0x00FFFFFF;
++	dc.col[defaultbg].pixel |= (unsigned char)(0xff * alpha) << 24;
+ 	loaded = 1;
+ }
+ 
+@@ -1134,11 +1144,23 @@ xinit(int cols, int rows)
+ 	Window parent;
+ 	pid_t thispid = getpid();
+ 	XColor xmousefg, xmousebg;
++	XWindowAttributes attr;
++	XVisualInfo vis;
+ 
+ 	if (!(xw.dpy = XOpenDisplay(NULL)))
+ 		die("can't open display\n");
+ 	xw.scr = XDefaultScreen(xw.dpy);
+-	xw.vis = XDefaultVisual(xw.dpy, xw.scr);
++
++	if (!(opt_embed && (parent = strtol(opt_embed, NULL, 0)))) {
++		parent = XRootWindow(xw.dpy, xw.scr);
++		xw.depth = 32;
++	} else {
++		XGetWindowAttributes(xw.dpy, parent, &attr);
++		xw.depth = attr.depth;
++	}
++
++	XMatchVisualInfo(xw.dpy, xw.scr, xw.depth, TrueColor, &vis);
++	xw.vis = vis.visual;
+ 
+ 	/* font */
+ 	if (!FcInit())
+@@ -1147,8 +1169,11 @@ xinit(int cols, int rows)
+ 	usedfont = (opt_font == NULL)? font : opt_font;
+ 	xloadfonts(usedfont, 0);
+ 
++   /* Backup default alpha value */
++   alpha_def = alpha;
++
+ 	/* colors */
+-	xw.cmap = XDefaultColormap(xw.dpy, xw.scr);
++	xw.cmap = XCreateColormap(xw.dpy, parent, xw.vis, None);
+ 	xloadcols();
+ 
+ 	/* adjust fixed window geometry */
+@@ -1168,19 +1193,15 @@ xinit(int cols, int rows)
+ 		| ButtonMotionMask | ButtonPressMask | ButtonReleaseMask;
+ 	xw.attrs.colormap = xw.cmap;
+ 
+-	if (!(opt_embed && (parent = strtol(opt_embed, NULL, 0))))
+-		parent = XRootWindow(xw.dpy, xw.scr);
+ 	xw.win = XCreateWindow(xw.dpy, parent, xw.l, xw.t,
+-			win.w, win.h, 0, XDefaultDepth(xw.dpy, xw.scr), InputOutput,
++			win.w, win.h, 0, xw.depth, InputOutput,
+ 			xw.vis, CWBackPixel | CWBorderPixel | CWBitGravity
+ 			| CWEventMask | CWColormap, &xw.attrs);
+ 
+ 	memset(&gcvalues, 0, sizeof(gcvalues));
+ 	gcvalues.graphics_exposures = False;
+-	dc.gc = XCreateGC(xw.dpy, parent, GCGraphicsExposures,
+-			&gcvalues);
+-	xw.buf = XCreatePixmap(xw.dpy, xw.win, win.w, win.h,
+-			DefaultDepth(xw.dpy, xw.scr));
++	xw.buf = XCreatePixmap(xw.dpy, xw.win, win.w, win.h, xw.depth);
++	dc.gc = XCreateGC(xw.dpy, xw.buf, GCGraphicsExposures, &gcvalues);
+ 	XSetForeground(xw.dpy, dc.gc, dc.col[defaultbg].pixel);
+ 	XFillRectangle(xw.dpy, xw.buf, dc.gc, 0, 0, win.w, win.h);
+ 
+@@ -1371,6 +1392,24 @@ xmakeglyphfontspecs(XftGlyphFontSpec *specs, const Glyph *glyphs, int len, int x
+ 	return numspecs;
+ }
+ 
++void
++chgalpha(const Arg *arg)
++{
++   if (arg->f == -1.0f && alpha >= 0.1f)
++      alpha -= 0.1f;
++   else if (arg->f == 1.0f && alpha < 1.0f)
++      alpha += 0.1f;
++   else if (arg->f == 0.0f)
++      alpha = alpha_def;
++   else
++      return;
++
++   dc.col[defaultbg].color.alpha = (unsigned short)(0xFFFF * alpha);
++   /* Required to remove artifacting from borderpx */
++   cresize(0, 0);
++   redraw();
++}
++
+ void
+ xdrawglyphfontspecs(const XftGlyphFontSpec *specs, Glyph base, int len, int x, int y)
+ {
+@@ -2038,6 +2077,9 @@ main(int argc, char *argv[])
+ 	case 'a':
+ 		allowaltscreen = 0;
+ 		break;
++	case 'A':
++		opt_alpha = EARGF(usage());
++		break;
+ 	case 'c':
+ 		opt_class = EARGF(usage());
+ 		break;

st.c

@@ -39,7 +39,7 @@
 
 /* macros */
 #define IS_SET(flag)		((term.mode & (flag)) != 0)
-#define ISCONTROLC0(c)		(BETWEEN(c, 0, 0x1f) || (c) == '\177')
+#define ISCONTROLC0(c)		(BETWEEN(c, 0, 0x1f) || (c) == 0x7f)
 #define ISCONTROLC1(c)		(BETWEEN(c, 0x80, 0x9f))
 #define ISCONTROL(c)		(ISCONTROLC0(c) || ISCONTROLC1(c))
 #define ISDELIM(u)		(u && wcschr(worddelimiters, u))
@@ -55,7 +55,6 @@ enum term_mode {
 	MODE_ECHO        = 1 << 4,
 	MODE_PRINT       = 1 << 5,
 	MODE_UTF8        = 1 << 6,
-	MODE_SIXEL       = 1 << 7,
 };
 
 enum cursor_movement {
@@ -82,12 +81,11 @@ enum charset {
 enum escape_state {
 	ESC_START      = 1,
 	ESC_CSI        = 2,
-	ESC_STR        = 4,  /* OSC, PM, APC */
+	ESC_STR        = 4,  /* DCS, OSC, PM, APC */
 	ESC_ALTCHARSET = 8,
 	ESC_STR_END    = 16, /* a final string was encountered */
 	ESC_TEST       = 32, /* Enter in test mode */
 	ESC_UTF8       = 64,
-	ESC_DCS        =128,
 };
 
 typedef struct {
@@ -136,6 +134,7 @@ typedef struct {
 	int charset;  /* current charset */
 	int icharset; /* selected charset for sequence */
 	int *tabs;
+	Rune lastc;   /* last printed char outside of sequence, 0 if control */
 } Term;
 
 /* CSI Escape sequence structs */
@@ -169,6 +168,7 @@ static void csidump(void);
 static void csihandle(void);
 static void csiparse(void);
 static void csireset(void);
+static void osc_color_response(int, int, int);
 static int eschandle(uchar);
 static void strdump(void);
 static void strhandle(void);
@@ -194,18 +194,18 @@ static void tputc(Rune);
 static void treset(void);
 static void tscrollup(int, int, int);
 static void tscrolldown(int, int, int);
-static void tsetattr(int *, int);
-static void tsetchar(Rune, Glyph *, int, int);
+static void tsetattr(const int *, int);
+static void tsetchar(Rune, const Glyph *, int, int);
 static void tsetdirt(int, int);
 static void tsetscroll(int, int);
 static void tswapscreen(void);
-static void tsetmode(int, int, int *, int);
+static void tsetmode(int, int, const int *, int);
 static int twrite(const char *, int, int);
 static void tfulldirt(void);
 static void tcontrolcode(uchar );
 static void tdectest(char );
 static void tdefutf8(char);
-static int32_t tdefcolor(int *, int *, int);
+static int32_t tdefcolor(const int *, int *, int);
 static void tdeftran(char);
 static void tstrsequence(uchar);
 
@@ -234,10 +234,10 @@ static int iofd = 1;
 static int cmdfd;
 static pid_t pid;
 
-static uchar utfbyte[UTF_SIZ + 1] = {0x80,    0, 0xC0, 0xE0, 0xF0};
-static uchar utfmask[UTF_SIZ + 1] = {0xC0, 0x80, 0xE0, 0xF0, 0xF8};
-static Rune utfmin[UTF_SIZ + 1] = {       0,    0,  0x80,  0x800,  0x10000};
-static Rune utfmax[UTF_SIZ + 1] = {0x10FFFF, 0x7F, 0x7FF, 0xFFFF, 0x10FFFF};
+static const uchar utfbyte[UTF_SIZ + 1] = {0x80,    0, 0xC0, 0xE0, 0xF0};
+static const uchar utfmask[UTF_SIZ + 1] = {0xC0, 0x80, 0xE0, 0xF0, 0xF8};
+static const Rune utfmin[UTF_SIZ + 1] = {       0,    0,  0x80,  0x800,  0x10000};
+static const Rune utfmax[UTF_SIZ + 1] = {0x10FFFF, 0x7F, 0x7FF, 0xFFFF, 0x10FFFF};
 
 ssize_t
 xwrite(int fd, const char *s, size_t len)
@@ -277,12 +277,14 @@ xrealloc(void *p, size_t len)
 }
 
 char *
-xstrdup(char *s)
+xstrdup(const char *s)
 {
-	if ((s = strdup(s)) == NULL)
+	char *p;
+
+	if ((p = strdup(s)) == NULL)
 		die("strdup: %s\n", strerror(errno));
 
-	return s;
+	return p;
 }
 
 size_t
@@ -355,25 +357,10 @@ utf8validate(Rune *u, size_t i)
 	return i;
 }
 
-static const char base64_digits[] = {
-	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
-	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 62, 0, 0, 0,
-	63, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 0, 0, 0, -1, 0, 0, 0, 0, 1,
-	2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21,
-	22, 23, 24, 25, 0, 0, 0, 0, 0, 0, 26, 27, 28, 29, 30, 31, 32, 33, 34,
-	35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 0,
-	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
-	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
-	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
-	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
-	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
-	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
-};
-
 char
 base64dec_getc(const char **src)
 {
-	while (**src && !isprint(**src))
+	while (**src && !isprint((unsigned char)**src))
 		(*src)++;
 	return **src ? *((*src)++) : '=';  /* emulate padding if string ends */
 }
@@ -383,6 +370,13 @@ base64dec(const char *src)
 {
 	size_t in_len = strlen(src);
 	char *result, *dst;
+	static const char base64_digits[256] = {
+		[43] = 62, 0, 0, 0, 63, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61,
+		0, 0, 0, -1, 0, 0, 0, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12,
+		13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 0, 0, 0, 0,
+		0, 0, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39,
+		40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51
+	};
 
 	if (in_len % 4)
 		in_len += 4 - (in_len % 4);
@@ -526,7 +520,7 @@ selsnap(int *x, int *y, int direction)
 {
 	int newx, newy, xt, yt;
 	int delim, prevdelim;
-	Glyph *gp, *prevgp;
+	const Glyph *gp, *prevgp;
 
 	switch (sel.snap) {
 	case SNAP_WORD:
@@ -599,7 +593,7 @@ getsel(void)
 {
 	char *str, *ptr;
 	int y, bufsize, lastx, linelen;
-	Glyph *gp, *last;
+	const Glyph *gp, *last;
 
 	if (sel.ob.x == -1)
 		return NULL;
@@ -641,7 +635,8 @@ getsel(void)
 		 * st.
 		 * FIXME: Fix the computer world.
 		 */
-		if ((y < sel.ne.y || lastx >= linelen) && !(last->mode & ATTR_WRAP))
+		if ((y < sel.ne.y || lastx >= linelen) &&
+		    (!(last->mode & ATTR_WRAP) || sel.type == SEL_RECTANGULAR))
 			*ptr++ = '\n';
 	}
 	*ptr = 0;
@@ -737,7 +732,7 @@ sigchld(int a)
 		die("child exited with status %d\n", WEXITSTATUS(stat));
 	else if (WIFSIGNALED(stat))
 		die("child terminated due to signal %d\n", WTERMSIG(stat));
-	exit(0);
+	_exit(0);
 }
 
 void
@@ -765,7 +760,7 @@ stty(char **args)
 }
 
 int
-ttynew(char *line, char *cmd, char *out, char **args)
+ttynew(const char *line, char *cmd, const char *out, char **args)
 {
 	int m, s;
 
@@ -798,14 +793,15 @@ ttynew(char *line, char *cmd, char *out, char **args)
 		break;
 	case 0:
 		close(iofd);
+		close(m);
 		setsid(); /* create a new process group */
 		dup2(s, 0);
 		dup2(s, 1);
 		dup2(s, 2);
 		if (ioctl(s, TIOCSCTTY, NULL) < 0)
 			die("ioctl TIOCSCTTY failed: %s\n", strerror(errno));
-		close(s);
-		close(m);
+		if (s > 2)
+			close(s);
 #ifdef __OpenBSD__
 		if (pledge("stdio getpw proc exec", NULL) == -1)
 			die("pledge\n");
@@ -848,7 +844,6 @@ ttyread(void)
 		if (buflen > 0)
 			memmove(buf, buf + written, buflen);
 		return ret;
-
 	}
 }
 
@@ -1163,27 +1158,17 @@ selscroll(int orig, int n)
 	if (sel.ob.x == -1)
 		return;
 
-	if (BETWEEN(sel.ob.y, orig, term.bot) || BETWEEN(sel.oe.y, orig, term.bot)) {
-		if ((sel.ob.y += n) > term.bot || (sel.oe.y += n) < term.top) {
+	if (BETWEEN(sel.nb.y, orig, term.bot) != BETWEEN(sel.ne.y, orig, term.bot)) {
+		selclear();
+	} else if (BETWEEN(sel.nb.y, orig, term.bot)) {
+		sel.ob.y += n;
+		sel.oe.y += n;
+		if (sel.ob.y < term.top || sel.ob.y > term.bot ||
+		    sel.oe.y < term.top || sel.oe.y > term.bot) {
 			selclear();
-			return;
-		}
-		if (sel.type == SEL_RECTANGULAR) {
-			if (sel.ob.y < term.top)
-				sel.ob.y = term.top;
-			if (sel.oe.y > term.bot)
-				sel.oe.y = term.bot;
 		} else {
-			if (sel.ob.y < term.top) {
-				sel.ob.y = term.top;
-				sel.ob.x = 0;
-			}
-			if (sel.oe.y > term.bot) {
-				sel.oe.y = term.bot;
-				sel.oe.x = term.col;
-			}
+			selnormalize();
 		}
-		selnormalize();
 	}
 }
 
@@ -1255,9 +1240,9 @@ tmoveto(int x, int y)
 }
 
 void
-tsetchar(Rune u, Glyph *attr, int x, int y)
+tsetchar(Rune u, const Glyph *attr, int x, int y)
 {
-	static char *vt100_0[62] = { /* 0x41 - 0x7e */
+	static const char *vt100_0[62] = { /* 0x41 - 0x7e */
 		"↑", "↓", "→", "←", "█", "▚", "☃", /* A - G */
 		0, 0, 0, 0, 0, 0, 0, 0, /* H - O */
 		0, 0, 0, 0, 0, 0, 0, 0, /* P - W */
@@ -1288,6 +1273,9 @@ tsetchar(Rune u, Glyph *attr, int x, int y)
 	term.dirty[y] = 1;
 	term.line[y][x] = *attr;
 	term.line[y][x].u = u;
+
+	if (isboxdraw(u))
+		term.line[y][x].mode |= ATTR_BOXDRAW;
 }
 
 void
@@ -1369,7 +1357,7 @@ tdeleteline(int n)
 }
 
 int32_t
-tdefcolor(int *attr, int *npar, int l)
+tdefcolor(const int *attr, int *npar, int l)
 {
 	int32_t idx = -1;
 	uint r, g, b;
@@ -1419,7 +1407,7 @@ tdefcolor(int *attr, int *npar, int l)
 }
 
 void
-tsetattr(int *attr, int l)
+tsetattr(const int *attr, int l)
 {
 	int i;
 	int32_t idx;
@@ -1537,9 +1525,9 @@ tsetscroll(int t, int b)
 }
 
 void
-tsetmode(int priv, int set, int *args, int narg)
+tsetmode(int priv, int set, const int *args, int narg)
 {
-	int alt, *lim;
+	int alt; const int *lim;
 
 	for (lim = args + narg; args < lim; ++args) {
 		if (priv) {
@@ -1715,6 +1703,12 @@ csihandle(void)
 		if (csiescseq.arg[0] == 0)
 			ttywrite(vtiden, strlen(vtiden), 0);
 		break;
+	case 'b': /* REP -- if last char is printable print it <n> more times */
+		DEFAULT(csiescseq.arg[0], 1);
+		if (term.lastc)
+			while (csiescseq.arg[0]-- > 0)
+				tputc(term.lastc);
+		break;
 	case 'C': /* CUF -- Cursor <n> Forward */
 	case 'a': /* HPR -- Cursor <n> Forward */
 		DEFAULT(csiescseq.arg[0], 1);
@@ -1838,7 +1832,7 @@ csihandle(void)
 		break;
 	case 'n': /* DSR – Device Status Report (cursor position) */
 		if (csiescseq.arg[0] == 6) {
-			len = snprintf(buf, sizeof(buf),"\033[%i;%iR",
+			len = snprintf(buf, sizeof(buf), "\033[%i;%iR",
 					term.c.y+1, term.c.x+1);
 			ttywrite(buf, len, 0);
 		}
@@ -1902,11 +1896,41 @@ csireset(void)
 	memset(&csiescseq, 0, sizeof(csiescseq));
 }
 
+void
+osc_color_response(int num, int index, int is_osc4)
+{
+	int n;
+	char buf[32];
+	unsigned char r, g, b;
+
+	if (xgetcolor(is_osc4 ? num : index, &r, &g, &b)) {
+		fprintf(stderr, "erresc: failed to fetch %s color %d\n",
+		        is_osc4 ? "osc4" : "osc",
+		        is_osc4 ? num : index);
+		return;
+	}
+
+	n = snprintf(buf, sizeof buf, "\033]%s%d;rgb:%02x%02x/%02x%02x/%02x%02x\007",
+	             is_osc4 ? "4;" : "", num, r, r, g, g, b, b);
+	if (n < 0 || n >= sizeof(buf)) {
+		fprintf(stderr, "error: %s while printing %s response\n",
+		        n < 0 ? "snprintf failed" : "truncation occurred",
+		        is_osc4 ? "osc4" : "osc");
+	} else {
+		ttywrite(buf, n, 1);
+	}
+}
+
 void
 strhandle(void)
 {
 	char *p = NULL, *dec;
 	int j, narg, par;
+	const struct { int idx; char *str; } osc_table[] = {
+		{ defaultfg, "foreground" },
+		{ defaultbg, "background" },
+		{ defaultcs, "cursor" }
+	};
 
 	term.esc &= ~(ESC_STR_END|ESC_STR);
 	strparse();
@@ -1916,13 +1940,21 @@ strhandle(void)
 	case ']': /* OSC -- Operating System Command */
 		switch (par) {
 		case 0:
+			if (narg > 1) {
+				xsettitle(strescseq.args[1]);
+				xseticontitle(strescseq.args[1]);
+			}
+			return;
 		case 1:
+			if (narg > 1)
+				xseticontitle(strescseq.args[1]);
+			return;
 		case 2:
 			if (narg > 1)
 				xsettitle(strescseq.args[1]);
 			return;
 		case 52:
-			if (narg > 2) {
+			if (narg > 2 && allowwindowops) {
 				dec = base64dec(strescseq.args[2]);
 				if (dec) {
 					xsetsel(dec);
@@ -1932,14 +1964,35 @@ strhandle(void)
 				}
 			}
 			return;
+		case 10:
+		case 11:
+		case 12:
+			if (narg < 2)
+				break;
+			p = strescseq.args[1];
+			if ((j = par - 10) < 0 || j >= LEN(osc_table))
+				break; /* shouldn't be possible */
+
+			if (!strcmp(p, "?")) {
+				osc_color_response(par, osc_table[j].idx, 0);
+			} else if (xsetcolorname(osc_table[j].idx, p)) {
+				fprintf(stderr, "erresc: invalid %s color: %s\n",
+				        osc_table[j].str, p);
+			} else {
+				tfulldirt();
+			}
+			return;
 		case 4: /* color set */
 			if (narg < 3)
 				break;
 			p = strescseq.args[2];
 			/* FALLTHROUGH */
-		case 104: /* color reset, here p = NULL */
+		case 104: /* color reset */
 			j = (narg > 1) ? atoi(strescseq.args[1]) : -1;
-			if (xsetcolorname(j, p)) {
+
+			if (p && !strcmp(p, "?")) {
+				osc_color_response(j, 0, 1);
+			} else if (xsetcolorname(j, p)) {
 				if (par == 104 && narg <= 1)
 					return; /* color reset without parameter */
 				fprintf(stderr, "erresc: invalid color j=%d, p=%s\n",
@@ -1949,7 +2002,7 @@ strhandle(void)
 				 * TODO if defaultbg color is changed, borders
 				 * are dirty
 				 */
-				redraw();
+				tfulldirt();
 			}
 			return;
 		}
@@ -1958,7 +2011,6 @@ strhandle(void)
 		xsettitle(strescseq.args[0]);
 		return;
 	case 'P': /* DCS -- Device Control String */
-		term.mode |= ESC_DCS;
 	case '_': /* APC -- Application Program Command */
 	case '^': /* PM -- Privacy Message */
 		return;
@@ -2076,12 +2128,12 @@ void
 tdumpline(int n)
 {
 	char buf[UTF_SIZ];
-	Glyph *bp, *end;
+	const Glyph *bp, *end;
 
 	bp = &term.line[n][0];
 	end = &bp[MIN(tlinelen(n), term.col) - 1];
 	if (bp != end || bp->u != ' ') {
-		for ( ;bp <= end; ++bp)
+		for ( ; bp <= end; ++bp)
 			tprinter(buf, utf8encode(bp->u, buf));
 	}
 	tprinter("\n", 1);
@@ -2152,12 +2204,9 @@ tdectest(char c)
 void
 tstrsequence(uchar c)
 {
-	strreset();
-
 	switch (c) {
 	case 0x90:   /* DCS -- Device Control String */
 		c = 'P';
-		term.esc |= ESC_DCS;
 		break;
 	case 0x9f:   /* APC -- Application Program Command */
 		c = '_';
@@ -2169,6 +2218,7 @@ tstrsequence(uchar c)
 		c = ']';
 		break;
 	}
+	strreset();
 	strescseq.type = c;
 	term.esc |= ESC_STR;
 }
@@ -2211,6 +2261,7 @@ tcontrolcode(uchar ascii)
 		return;
 	case '\032': /* SUB */
 		tsetchar('?', &term.c.attr, term.c.x, term.c.y);
+		/* FALLTHROUGH */
 	case '\030': /* CAN */
 		csireset();
 		break;
@@ -2365,15 +2416,13 @@ tputc(Rune u)
 	Glyph *gp;
 
 	control = ISCONTROL(u);
-	if (!IS_SET(MODE_UTF8) && !IS_SET(MODE_SIXEL)) {
+	if (u < 127 || !IS_SET(MODE_UTF8)) {
 		c[0] = u;
 		width = len = 1;
 	} else {
 		len = utf8encode(u, c);
-		if (!control && (width = wcwidth(u)) == -1) {
-			memcpy(c, "\357\277\275", 4); /* UTF_INVALID */
+		if (!control && (width = wcwidth(u)) == -1)
 			width = 1;
-		}
 	}
 
 	if (IS_SET(MODE_PRINT))
@@ -2388,23 +2437,11 @@ tputc(Rune u)
 	if (term.esc & ESC_STR) {
 		if (u == '\a' || u == 030 || u == 032 || u == 033 ||
 		   ISCONTROLC1(u)) {
-			term.esc &= ~(ESC_START|ESC_STR|ESC_DCS);
-			if (IS_SET(MODE_SIXEL)) {
-				/* TODO: render sixel */;
-				term.mode &= ~MODE_SIXEL;
-				return;
-			}
+			term.esc &= ~(ESC_START|ESC_STR);
 			term.esc |= ESC_STR_END;
 			goto check_control_code;
 		}
 
-		if (IS_SET(MODE_SIXEL)) {
-			/* TODO: implement sixel mode */
-			return;
-		}
-		if (term.esc&ESC_DCS && strescseq.len == 0 && u == 'q')
-			term.mode |= MODE_SIXEL;
-
 		if (strescseq.len+len >= strescseq.siz) {
 			/*
 			 * Here is a bug in terminals. If the user never sends
@@ -2441,6 +2478,8 @@ check_control_code:
 		/*
 		 * control codes are not shown ever
 		 */
+		if (!term.esc)
+			term.lastc = 0;
 		return;
 	} else if (term.esc & ESC_START) {
 		if (term.esc & ESC_CSI) {
@@ -2471,7 +2510,7 @@ check_control_code:
 		 */
 		return;
 	}
-	if (sel.ob.x != -1 && BETWEEN(term.c.y, sel.ob.y, sel.oe.y))
+	if (selected(term.c.x, term.c.y))
 		selclear();
 
 	gp = &term.line[term.c.y][term.c.x];
@@ -2490,10 +2529,15 @@ check_control_code:
 	}
 
 	tsetchar(u, &term.c.attr, term.c.x, term.c.y);
+	term.lastc = u;
 
 	if (width == 2) {
 		gp->mode |= ATTR_WIDE;
 		if (term.c.x+1 < term.col) {
+			if (gp[1].mode == ATTR_WIDE && term.c.x+2 < term.col) {
+				gp[2].u = ' ';
+				gp[2].mode &= ~ATTR_WDUMMY;
+			}
 			gp[1].u = '\0';
 			gp[1].mode = ATTR_WDUMMY;
 		}
@@ -2513,7 +2557,7 @@ twrite(const char *buf, int buflen, int show_ctrl)
 	int n;
 
 	for (n = 0; n < buflen; n += charsize) {
-		if (IS_SET(MODE_UTF8) && !IS_SET(MODE_SIXEL)) {
+		if (IS_SET(MODE_UTF8)) {
 			/* process a complete utf8 char */
 			charsize = utf8decode(buf + n, &u, buflen - n);
 			if (charsize == 0)
@@ -2666,7 +2710,8 @@ draw(void)
 	drawregion(0, 0, term.col, term.row);
 	if (term.scr == 0)
 		xdrawcursor(cx, term.c.y, term.line[term.c.y][cx],
-			term.ocx, term.ocy, term.line[term.ocy][term.ocx]);
+			term.ocx, term.ocy, term.line[term.ocy][term.ocx],
+			term.line[term.ocy], term.col);
 	term.ocx = cx;
 	term.ocy = term.c.y;
 	xfinishdraw();

st.desktop

@@ -0,0 +1,8 @@
+[Desktop Entry]
+Name=st
+Comment=st is a simple terminal implementation for X
+Exec=st
+Icon=utilities-terminal
+Terminal=false
+Type=Application
+Categories=System;TerminalEmulator;

st.h

@@ -11,7 +11,8 @@
 #define DIVCEIL(n, d)		(((n) + ((d) - 1)) / (d))
 #define DEFAULT(a, b)		(a) = (a) ? (a) : (b)
 #define LIMIT(x, a, b)		(x) = (x) < (a) ? (a) : (x) > (b) ? (b) : (x)
-#define ATTRCMP(a, b)		((a).mode != (b).mode || (a).fg != (b).fg || \
+#define ATTRCMP(a, b)		(((a).mode & (~ATTR_WRAP) & (~ATTR_LIGA)) != ((b).mode & (~ATTR_WRAP) & (~ATTR_LIGA)) || \
+				(a).fg != (b).fg || \
 				(a).bg != (b).bg)
 #define TIMEDIFF(t1, t2)	((t1.tv_sec-t2.tv_sec)*1000 + \
 				(t1.tv_nsec-t2.tv_nsec)/1E6)
@@ -33,6 +34,8 @@ enum glyph_attribute {
 	ATTR_WRAP       = 1 << 8,
 	ATTR_WIDE       = 1 << 9,
 	ATTR_WDUMMY     = 1 << 10,
+	ATTR_BOXDRAW    = 1 << 11,
+	ATTR_LIGA       = 1 << 12,
 	ATTR_BOLD_FAINT = ATTR_BOLD | ATTR_FAINT,
 };
 
@@ -93,7 +96,7 @@ void tnew(int, int);
 void tresize(int, int);
 void tsetdirtattr(int);
 void ttyhangup(void);
-int ttynew(char *, char *, char *, char **);
+int ttynew(const char *, char *, const char *, char **);
 size_t ttyread(void);
 void ttyresize(int, int);
 void ttywrite(const char *, size_t, int);
@@ -111,7 +114,15 @@ size_t utf8encode(Rune, char *);
 
 void *xmalloc(size_t);
 void *xrealloc(void *, size_t);
-char *xstrdup(char *);
+char *xstrdup(const char *);
+
+int isboxdraw(Rune);
+ushort boxdrawindex(const Glyph *);
+#ifdef XFT_VERSION
+/* only exposed to x.c, otherwise we'll need Xft.h for the types */
+void boxdraw_xinit(Display *, Colormap, XftDraw *, Visual *);
+void drawboxes(int, int, int, int, XftColor *, XftColor *, const XftGlyphFontSpec *, int);
+#endif
 
 /* config.h globals */
 extern char *utmp;
@@ -120,8 +131,12 @@ extern char *stty_args;
 extern char *vtiden;
 extern wchar_t *worddelimiters;
 extern int allowaltscreen;
+extern int allowwindowops;
 extern char *termname;
 extern unsigned int tabspaces;
 extern unsigned int defaultfg;
 extern unsigned int defaultbg;
+extern unsigned int defaultcs;
+extern float alpha, alpha_def;
+extern const int boxdraw, boxdraw_bold, boxdraw_braille;
 extern float alpha;

st.info

@@ -158,6 +158,7 @@ st-mono| simpleterm monocolor,
 	rc=\E8,
 	rev=\E[7m,
 	ri=\EM,
+	rin=\E[%p1%dT,
 	ritm=\E[23m,
 	rmacs=\E(B,
 	rmcup=\E[?1049l,
@@ -183,6 +184,8 @@ st-mono| simpleterm monocolor,
 # XTerm extensions
 	rmxx=\E[29m,
 	smxx=\E[9m,
+# disabled rep for now: causes some issues with older ncurses versions.
+#	rep=%p1%c\E[%p2%{1}%-%db,
 # tmux extensions, see TERMINFO EXTENSIONS in tmux(1)
 	Tc,
 	Ms=\E]52;%p1%s;%p2%s\007,

win.h

@@ -25,11 +25,13 @@ enum win_mode {
 
 void xbell(void);
 void xclipcopy(void);
-void xdrawcursor(int, int, Glyph, int, int, Glyph);
+void xdrawcursor(int, int, Glyph, int, int, Glyph, Line, int);
 void xdrawline(Line, int, int, int);
 void xfinishdraw(void);
 void xloadcols(void);
 int xsetcolorname(int, const char *);
+int xgetcolor(int, unsigned char *, unsigned char *, unsigned char *);
+void xseticontitle(char *);
 void xsettitle(char *);
 int xsetcursor(int);
 void xsetmode(int, unsigned int);

x.c

@@ -19,6 +19,7 @@ char *argv0;
 #include "arg.h"
 #include "st.h"
 #include "win.h"
+#include "hb.h"
 
 /* types used in config.h */
 typedef struct {
@@ -48,7 +49,7 @@ typedef struct {
 /* X modifiers */
 #define XK_ANY_MOD    UINT_MAX
 #define XK_NO_MOD     0
-#define XK_SWITCH_MOD (1<<13)
+#define XK_SWITCH_MOD (1<<13|1<<14)
 
 /* function definitions used in config.h */
 static void clipcopy(const Arg *);
@@ -58,8 +59,8 @@ static void selpaste(const Arg *);
 static void zoom(const Arg *);
 static void zoomabs(const Arg *);
 static void zoomreset(const Arg *);
-static void setpalette(const Arg *);
 static void ttysend(const Arg *);
+static void chgalpha(const Arg *);
 
 /* config.h for applying patches and the configuration. */
 #include "config.h"
@@ -82,6 +83,7 @@ typedef XftGlyphFontSpec GlyphFontSpec;
 typedef struct {
 	int tw, th; /* tty width and height */
 	int w, h; /* window width and height */
+	int hborderpx, vborderpx;
 	int ch; /* char height */
 	int cw; /* char width  */
 	int mode; /* window state/mode flags */
@@ -94,7 +96,7 @@ typedef struct {
 	Window win;
 	Drawable buf;
 	GlyphFontSpec *specbuf; /* font spec buffer used for rendering */
-	Atom xembed, wmdeletewin, netwmname, netwmpid;
+	Atom xembed, wmdeletewin, netwmname, netwmiconname, netwmpid;
 	struct {
 		XIM xim;
 		XIC xic;
@@ -158,7 +160,7 @@ static void xresize(int, int);
 static void xhints(void);
 static int xloadcolor(int, const char *, Color *);
 static int xloadfont(Font *, FcPattern *);
-static void xloadfonts(char *, double);
+static void xloadfonts(const char *, double);
 static void xunloadfont(Font *);
 static void xunloadfonts(void);
 static void xsetenv(void);
@@ -255,7 +257,7 @@ static char *opt_line  = NULL;
 static char *opt_name  = NULL;
 static char *opt_title = NULL;
 
-static int oldbutton = 3; /* button event on startup: 3 = release */
+static uint buttons; /* bit field of pressed buttons */
 
 void
 clipcopy(const Arg *dummy)
@@ -334,7 +336,7 @@ ttysend(const Arg *arg)
 int
 evcol(XEvent *e)
 {
-	int x = e->xbutton.x - borderpx;
+	int x = e->xbutton.x - win.hborderpx;
 	LIMIT(x, 0, win.tw - 1);
 	return x / win.cw;
 }
@@ -342,7 +344,7 @@ evcol(XEvent *e)
 int
 evrow(XEvent *e)
 {
-	int y = e->xbutton.y - borderpx;
+	int y = e->xbutton.y - win.vborderpx;
 	LIMIT(y, 0, win.th - 1);
 	return y / win.ch;
 }
@@ -367,59 +369,68 @@ mousesel(XEvent *e, int done)
 void
 mousereport(XEvent *e)
 {
-	int len, x = evcol(e), y = evrow(e),
-	    button = e->xbutton.button, state = e->xbutton.state;
+	int len, btn, code;
+	int x = evcol(e), y = evrow(e);
+	int state = e->xbutton.state;
 	char buf[40];
 	static int ox, oy;
 
-	/* from urxvt */
-	if (e->xbutton.type == MotionNotify) {
+	if (e->type == MotionNotify) {
 		if (x == ox && y == oy)
 			return;
 		if (!IS_SET(MODE_MOUSEMOTION) && !IS_SET(MODE_MOUSEMANY))
 			return;
-		/* MOUSE_MOTION: no reporting if no button is pressed */
-		if (IS_SET(MODE_MOUSEMOTION) && oldbutton == 3)
+		/* MODE_MOUSEMOTION: no reporting if no button is pressed */
+		if (IS_SET(MODE_MOUSEMOTION) && buttons == 0)
 			return;
-
-		button = oldbutton + 32;
-		ox = x;
-		oy = y;
+		/* Set btn to lowest-numbered pressed button, or 12 if no
+		 * buttons are pressed. */
+		for (btn = 1; btn <= 11 && !(buttons & (1<<(btn-1))); btn++)
+			;
+		code = 32;
 	} else {
-		if (!IS_SET(MODE_MOUSESGR) && e->xbutton.type == ButtonRelease) {
-			button = 3;
-		} else {
-			button -= Button1;
-			if (button >= 3)
-				button += 64 - 3;
-		}
-		if (e->xbutton.type == ButtonPress) {
-			oldbutton = button;
-			ox = x;
-			oy = y;
-		} else if (e->xbutton.type == ButtonRelease) {
-			oldbutton = 3;
+		btn = e->xbutton.button;
+		/* Only buttons 1 through 11 can be encoded */
+		if (btn < 1 || btn > 11)
+			return;
+		if (e->type == ButtonRelease) {
 			/* MODE_MOUSEX10: no button release reporting */
 			if (IS_SET(MODE_MOUSEX10))
 				return;
-			if (button == 64 || button == 65)
+			/* Don't send release events for the scroll wheel */
+			if (btn == 4 || btn == 5)
 				return;
 		}
+		code = 0;
 	}
 
+	ox = x;
+	oy = y;
+
+	/* Encode btn into code. If no button is pressed for a motion event in
+	 * MODE_MOUSEMANY, then encode it as a release. */
+	if ((!IS_SET(MODE_MOUSESGR) && e->type == ButtonRelease) || btn == 12)
+		code += 3;
+	else if (btn >= 8)
+		code += 128 + btn - 8;
+	else if (btn >= 4)
+		code += 64 + btn - 4;
+	else
+		code += btn - 1;
+
 	if (!IS_SET(MODE_MOUSEX10)) {
-		button += ((state & ShiftMask  ) ? 4  : 0)
-			+ ((state & Mod4Mask   ) ? 8  : 0)
-			+ ((state & ControlMask) ? 16 : 0);
+		code += ((state & ShiftMask  ) ?  4 : 0)
+		      + ((state & Mod1Mask   ) ?  8 : 0) /* meta key: alt */
+		      + ((state & ControlMask) ? 16 : 0);
 	}
 
 	if (IS_SET(MODE_MOUSESGR)) {
 		len = snprintf(buf, sizeof(buf), "\033[<%d;%d;%d%c",
-				button, x+1, y+1,
-				e->xbutton.type == ButtonRelease ? 'm' : 'M');
+				code, x+1, y+1,
+				e->type == ButtonRelease ? 'm' : 'M');
 	} else if (x < 223 && y < 223) {
 		len = snprintf(buf, sizeof(buf), "\033[M%c%c%c",
-				32+button, 32+x+1, 32+y+1);
+				32+code, 32+x+1, 32+y+1);
 	} else {
 		return;
 	}
@@ -462,9 +473,13 @@ mouseaction(XEvent *e, uint release)
 void
 bpress(XEvent *e)
 {
+	int btn = e->xbutton.button;
 	struct timespec now;
 	int snap;
 
+	if (1 <= btn && btn <= 11)
+		buttons |= 1 << (btn-1);
+
 	if (IS_SET(MODE_MOUSE) && !(e->xbutton.state & forcemousemod)) {
 		mousereport(e);
 		return;
@@ -473,7 +488,7 @@ bpress(XEvent *e)
 	if (mouseaction(e, 0))
 		return;
 
-	if (e->xbutton.button == Button1) {
+	if (btn == Button1) {
 		/*
 		 * If the user clicks below predefined timeouts specific
 		 * snapping behaviour is exposed.
@@ -687,6 +702,11 @@ xsetsel(char *str)
 void
 brelease(XEvent *e)
 {
+	int btn = e->xbutton.button;
+
+	if (1 <= btn && btn <= 11)
+		buttons &= ~(1 << (btn-1));
+
 	if (IS_SET(MODE_MOUSE) && !(e->xbutton.state & forcemousemod)) {
 		mousereport(e);
 		return;
@@ -694,7 +714,7 @@ brelease(XEvent *e)
 
 	if (mouseaction(e, 1))
 		return;
-	if (e->xbutton.button == Button1)
+	if (btn == Button1)
 		mousesel(e, 1);
 }
 
@@ -724,6 +744,9 @@ cresize(int width, int height)
 	col = MAX(1, col);
 	row = MAX(1, row);
 
+	win.hborderpx = (win.w - col * win.cw) / 2;
+	win.vborderpx = (win.h - row * win.ch) / 2;
+
 	tresize(col, row);
 	xresize(col, row);
 	ttyresize(win.tw, win.th);
@@ -754,7 +777,24 @@ sixd_to_16bit(int x)
 int
 xloadcolor(int i, const char *name, Color *ncolor)
 {
-	if (!name)  name = colorname[i];
+	XRenderColor color = { .alpha = 0xffff };
+
+	if (!name) {
+		if (BETWEEN(i, 16, 255)) { /* 256 color */
+			if (i < 6*6*6+16) { /* same colors as xterm */
+				color.red   = sixd_to_16bit( ((i-16)/36)%6 );
+				color.green = sixd_to_16bit( ((i-16)/6) %6 );
+				color.blue  = sixd_to_16bit( ((i-16)/1) %6 );
+			} else { /* greyscale */
+				color.red = 0x0808 + 0x0a0a * (i - (6*6*6+16));
+				color.green = color.blue = color.red;
+			}
+			return XftColorAllocValue(xw.dpy, xw.vis,
+			                          xw.cmap, &color, ncolor);
+		} else
+			name = colorname[i];
+	}
+
 	return XftColorAllocName(xw.dpy, xw.vis, xw.cmap, name, ncolor);
 }
 
@@ -765,11 +805,11 @@ xloadcols(void)
 	static int loaded;
 	Color *cp;
 
-    dc.collen = 16;
 	if (loaded) {
 		for (cp = dc.col; cp < &dc.col[dc.collen]; ++cp)
 			XftColorFree(xw.dpy, xw.vis, xw.cmap, cp);
 	} else {
+		dc.collen = MAX(LEN(colorname), 256);
 		dc.col = xmalloc(dc.collen * sizeof(Color));
 	}
 
@@ -790,6 +830,19 @@ xloadcols(void)
 	loaded = 1;
 }
 
+int
+xgetcolor(int x, unsigned char *r, unsigned char *g, unsigned char *b)
+{
+	if (!BETWEEN(x, 0, dc.collen))
+		return 1;
+
+	*r = dc.col[x].color.red >> 8;
+	*g = dc.col[x].color.green >> 8;
+	*b = dc.col[x].color.blue >> 8;
+
+	return 0;
+}
+
 int
 xsetcolorname(int x, const char *name)
 {
@@ -831,8 +884,8 @@ xhints(void)
 	sizeh->flags = PSize | PResizeInc | PBaseSize | PMinSize;
 	sizeh->height = win.h;
 	sizeh->width = win.w;
-	sizeh->height_inc = win.ch;
-	sizeh->width_inc = win.cw;
+	sizeh->height_inc = 1;
+	sizeh->width_inc = 1;
 	sizeh->base_height = 2 * borderpx;
 	sizeh->base_width = 2 * borderpx;
 	sizeh->min_height = win.ch + 2 * borderpx;
@@ -943,7 +996,7 @@ xloadfont(Font *f, FcPattern *pattern)
 }
 
 void
-xloadfonts(char *fontstr, double fontsize)
+xloadfonts(const char *fontstr, double fontsize)
 {
 	FcPattern *pattern;
 	double fontval;
@@ -951,7 +1004,7 @@ xloadfonts(char *fontstr, double fontsize)
 	if (fontstr[0] == '-')
 		pattern = XftXlfdParse(fontstr, False, False);
 	else
-		pattern = FcNameParse((FcChar8 *)fontstr);
+		pattern = FcNameParse((const FcChar8 *)fontstr);
 
 	if (!pattern)
 		die("can't open font %s\n", fontstr);
@@ -1024,6 +1077,9 @@ xunloadfont(Font *f)
 void
 xunloadfonts(void)
 {
+	/* Clear Harfbuzz font cache. */
+	hbunloadfonts();
+
 	/* Free the loaded fonts in the font cache.  */
 	while (frclen > 0)
 		XftFontClose(xw.dpy, frc[--frclen].font);
@@ -1121,13 +1177,16 @@ xinit(int cols, int rows)
 	usedfont = (opt_font == NULL)? font : opt_font;
 	xloadfonts(usedfont, 0);
 
+   /* Backup default alpha value */
+   alpha_def = alpha;
+
 	/* colors */
 	xw.cmap = XCreateColormap(xw.dpy, parent, xw.vis, None);
 	xloadcols();
 
 	/* adjust fixed window geometry */
-	win.w = 2 * borderpx + cols * win.cw;
-	win.h = 2 * borderpx + rows * win.ch;
+	win.w = 2 * win.hborderpx + cols * win.cw;
+	win.h = 2 * win.vborderpx + rows * win.ch;
 	if (xw.gm & XNegative)
 		xw.l += DisplayWidth(xw.dpy, xw.scr) - win.w - 2;
 	if (xw.gm & YNegative)
@@ -1187,6 +1246,7 @@ xinit(int cols, int rows)
 	xw.xembed = XInternAtom(xw.dpy, "_XEMBED", False);
 	xw.wmdeletewin = XInternAtom(xw.dpy, "WM_DELETE_WINDOW", False);
 	xw.netwmname = XInternAtom(xw.dpy, "_NET_WM_NAME", False);
+	xw.netwmiconname = XInternAtom(xw.dpy, "_NET_WM_ICON_NAME", False);
 	XSetWMProtocols(xw.dpy, xw.win, &xw.wmdeletewin, 1);
 
 	xw.netwmpid = XInternAtom(xw.dpy, "_NET_WM_PID", False);
@@ -1206,12 +1266,14 @@ xinit(int cols, int rows)
 	xsel.xtarget = XInternAtom(xw.dpy, "UTF8_STRING", 0);
 	if (xsel.xtarget == None)
 		xsel.xtarget = XA_STRING;
+
+	boxdraw_xinit(xw.dpy, xw.cmap, xw.draw, xw.vis);
 }
 
 int
 xmakeglyphfontspecs(XftGlyphFontSpec *specs, const Glyph *glyphs, int len, int x, int y)
 {
-	float winx = borderpx + x * win.cw, winy = borderpx + y * win.ch, xp, yp;
+	float winx = win.hborderpx + x * win.cw, winy = win.vborderpx + y * win.ch, xp, yp;
 	ushort mode, prevmode = USHRT_MAX;
 	Font *font = &dc.font;
 	int frcflags = FRC_NORMAL;
@@ -1230,7 +1292,7 @@ xmakeglyphfontspecs(XftGlyphFontSpec *specs, const Glyph *glyphs, int len, int x
 		mode = glyphs[i].mode;
 
 		/* Skip dummy wide-character spacing. */
-		if (mode == ATTR_WDUMMY)
+		if (mode & ATTR_WDUMMY)
 			continue;
 
 		/* Determine font for glyph if different from previous glyph. */
@@ -1252,8 +1314,13 @@ xmakeglyphfontspecs(XftGlyphFontSpec *specs, const Glyph *glyphs, int len, int x
 			yp = winy + font->ascent;
 		}
 
-		/* Lookup character index with default font. */
-		glyphidx = XftCharIndex(xw.dpy, font->match, rune);
+		if (mode & ATTR_BOXDRAW) {
+			/* minor shoehorning: boxdraw uses only this ushort */
+			glyphidx = boxdrawindex(&glyphs[i]);
+		} else {
+			/* Lookup character index with default font. */
+			glyphidx = XftCharIndex(xw.dpy, font->match, rune);
+		}
 		if (glyphidx) {
 			specs[numspecs].font = font->match;
 			specs[numspecs].glyph = glyphidx;
@@ -1337,14 +1404,40 @@ xmakeglyphfontspecs(XftGlyphFontSpec *specs, const Glyph *glyphs, int len, int x
 		numspecs++;
 	}
 
+	/* Harfbuzz transformation for ligatures. */
+	hbtransform(specs, glyphs, len, x, y);
+
 	return numspecs;
 }
 
+void
+chgalpha(const Arg *arg)
+{
+   if (arg->f == -1.0f && alpha >= 0.1f)
+      alpha -= 0.1f;
+   else if (arg->f == 1.0f && alpha < 1.0f)
+      alpha += 0.1f;
+   else if (arg->f == 0.0f)
+      alpha = alpha_def;
+   else
+      return;
+   
+   if(alpha < 0)
+       alpha = 0;
+   if(alpha > 1)
+       alpha = 1;
+
+   dc.col[defaultbg].color.alpha = (unsigned short)(0xFFFF * alpha);
+   /* Required to remove artifacting from borderpx */
+   cresize(0, 0);
+   redraw();
+}
+
 void
 xdrawglyphfontspecs(const XftGlyphFontSpec *specs, Glyph base, int len, int x, int y)
 {
 	int charlen = len * ((base.mode & ATTR_WIDE) ? 2 : 1);
-	int winx = borderpx + x * win.cw, winy = borderpx + y * win.ch,
+	int winx = win.hborderpx + x * win.cw, winy = win.vborderpx + y * win.ch,
 	    width = charlen * win.cw;
 	Color *fg, *bg, *temp, revfg, revbg, truefg, truebg;
 	XRenderColor colfg, colbg;
@@ -1434,17 +1527,17 @@ xdrawglyphfontspecs(const XftGlyphFontSpec *specs, Glyph base, int len, int x, i
 
 	/* Intelligent cleaning up of the borders. */
 	if (x == 0) {
-		xclear(0, (y == 0)? 0 : winy, borderpx,
+		xclear(0, (y == 0)? 0 : winy, win.vborderpx,
 			winy + win.ch +
-			((winy + win.ch >= borderpx + win.th)? win.h : 0));
+			((winy + win.ch >= win.vborderpx + win.th)? win.h : 0));
 	}
-	if (winx + width >= borderpx + win.tw) {
+	if (winx + width >= win.hborderpx + win.tw) {
 		xclear(winx + width, (y == 0)? 0 : winy, win.w,
-			((winy + win.ch >= borderpx + win.th)? win.h : (winy + win.ch)));
+			((winy + win.ch >= win.vborderpx + win.th)? win.h : (winy + win.ch)));
 	}
 	if (y == 0)
-		xclear(winx, 0, winx + width, borderpx);
-	if (winy + win.ch >= borderpx + win.th)
+		xclear(winx, 0, winx + width, win.hborderpx);
+	if (winy + win.ch >= win.vborderpx + win.th)
 		xclear(winx, winy + win.ch, winx + width, win.h);
 
 	/* Clean up the region we want to draw to. */
@@ -1457,17 +1550,21 @@ xdrawglyphfontspecs(const XftGlyphFontSpec *specs, Glyph base, int len, int x, i
 	r.width = width;
 	XftDrawSetClipRectangles(xw.draw, winx, winy, &r, 1);
 
-	/* Render the glyphs. */
-	XftDrawGlyphFontSpec(xw.draw, fg, specs, len);
+	if (base.mode & ATTR_BOXDRAW) {
+		drawboxes(winx, winy, width / len, win.ch, fg, bg, specs, len);
+	} else {
+		/* Render the glyphs. */
+		XftDrawGlyphFontSpec(xw.draw, fg, specs, len);
+	}
 
 	/* Render underline and strikethrough. */
 	if (base.mode & ATTR_UNDERLINE) {
-		XftDrawRect(xw.draw, fg, winx, winy + dc.font.ascent + 1,
+		XftDrawRect(xw.draw, fg, winx, winy + dc.font.ascent * chscale + 1,
 				width, 1);
 	}
 
 	if (base.mode & ATTR_STRUCK) {
-		XftDrawRect(xw.draw, fg, winx, winy + 2 * dc.font.ascent / 3,
+		XftDrawRect(xw.draw, fg, winx, winy + 2 * dc.font.ascent * chscale / 3,
 				width, 1);
 	}
 
@@ -1486,14 +1583,17 @@ xdrawglyph(Glyph g, int x, int y)
 }
 
 void
-xdrawcursor(int cx, int cy, Glyph g, int ox, int oy, Glyph og)
+xdrawcursor(int cx, int cy, Glyph g, int ox, int oy, Glyph og, Line line, int len)
 {
 	Color drawcol;
 
 	/* remove the old cursor */
 	if (selected(ox, oy))
 		og.mode ^= ATTR_REVERSE;
-	xdrawglyph(og, ox, oy);
+
+	/* Redraw the line where cursor was previously.
+	 * It will restore the ligatures broken by the cursor. */
+	xdrawline(line, 0, oy, len);
 
 	if (IS_SET(MODE_HIDE))
 		return;
@@ -1501,7 +1601,7 @@ xdrawcursor(int cx, int cy, Glyph g, int ox, int oy, Glyph og)
 	/*
 	 * Select the right color for the right mode.
 	 */
-	g.mode &= ATTR_BOLD|ATTR_ITALIC|ATTR_UNDERLINE|ATTR_STRUCK|ATTR_WIDE;
+	g.mode &= ATTR_BOLD|ATTR_ITALIC|ATTR_UNDERLINE|ATTR_STRUCK|ATTR_WIDE|ATTR_BOXDRAW;
 
 	if (IS_SET(MODE_REVERSE)) {
 		g.mode |= ATTR_REVERSE;
@@ -1527,8 +1627,9 @@ xdrawcursor(int cx, int cy, Glyph g, int ox, int oy, Glyph og)
 	/* draw the new one */
 	if (IS_SET(MODE_FOCUSED)) {
 		switch (win.cursor) {
-		case 7: /* st extension: snowman (U+2603) */
-			g.u = 0x2603;
+		case 7: /* st extension */
+			g.u = 0x2603; /* snowman (U+2603) */
+			/* FALLTHROUGH */
 		case 0: /* Blinking Block */
 		case 1: /* Blinking Block (Default) */
 		case 2: /* Steady Block */
@@ -1537,35 +1638,35 @@ xdrawcursor(int cx, int cy, Glyph g, int ox, int oy, Glyph og)
 		case 3: /* Blinking Underline */
 		case 4: /* Steady Underline */
 			XftDrawRect(xw.draw, &drawcol,
-					borderpx + cx * win.cw,
-					borderpx + (cy + 1) * win.ch - \
+					win.hborderpx + cx * win.cw,
+					win.vborderpx + (cy + 1) * win.ch - \
 						cursorthickness,
 					win.cw, cursorthickness);
 			break;
 		case 5: /* Blinking bar */
 		case 6: /* Steady bar */
 			XftDrawRect(xw.draw, &drawcol,
-					borderpx + cx * win.cw,
-					borderpx + cy * win.ch,
+					win.hborderpx + cx * win.cw,
+					win.vborderpx + cy * win.ch,
 					cursorthickness, win.ch);
 			break;
 		}
 	} else {
 		XftDrawRect(xw.draw, &drawcol,
-				borderpx + cx * win.cw,
-				borderpx + cy * win.ch,
+				win.hborderpx + cx * win.cw,
+				win.vborderpx + cy * win.ch,
 				win.cw - 1, 1);
 		XftDrawRect(xw.draw, &drawcol,
-				borderpx + cx * win.cw,
-				borderpx + cy * win.ch,
+				win.hborderpx + cx * win.cw,
+				win.vborderpx + cy * win.ch,
 				1, win.ch - 1);
 		XftDrawRect(xw.draw, &drawcol,
-				borderpx + (cx + 1) * win.cw - 1,
-				borderpx + cy * win.ch,
+				win.hborderpx + (cx + 1) * win.cw - 1,
+				win.vborderpx + cy * win.ch,
 				1, win.ch - 1);
 		XftDrawRect(xw.draw, &drawcol,
-				borderpx + cx * win.cw,
-				borderpx + (cy + 1) * win.ch - 1,
+				win.hborderpx + cx * win.cw,
+				win.vborderpx + (cy + 1) * win.ch - 1,
 				win.cw, 1);
 	}
 }
@@ -1579,14 +1680,29 @@ xsetenv(void)
 	setenv("WINDOWID", buf, 1);
 }
 
+void
+xseticontitle(char *p)
+{
+	XTextProperty prop;
+	DEFAULT(p, opt_title);
+
+	if (Xutf8TextListToTextProperty(xw.dpy, &p, 1, XUTF8StringStyle,
+	                                &prop) != Success)
+		return;
+	XSetWMIconName(xw.dpy, xw.win, &prop);
+	XSetTextProperty(xw.dpy, xw.win, &prop, xw.netwmiconname);
+	XFree(prop.value);
+}
+
 void
 xsettitle(char *p)
 {
 	XTextProperty prop;
 	DEFAULT(p, opt_title);
 
-	Xutf8TextListToTextProperty(xw.dpy, &p, 1, XUTF8StringStyle,
-			&prop);
+	if (Xutf8TextListToTextProperty(xw.dpy, &p, 1, XUTF8StringStyle,
+	                                &prop) != Success)
+		return;
 	XSetWMName(xw.dpy, xw.win, &prop);
 	XSetTextProperty(xw.dpy, xw.win, &prop, xw.netwmname);
 	XFree(prop.value);
@@ -1690,8 +1806,7 @@ xsetmode(int set, unsigned int flags)
 int
 xsetcursor(int cursor)
 {
-	DEFAULT(cursor, 1);
-	if (!BETWEEN(cursor, 0, 6))
+	if (!BETWEEN(cursor, 0, 7)) /* 7: st extension */
 		return 1;
 	win.cursor = cursor;
 	return 0;
@@ -1868,10 +1983,9 @@ run(void)
 	XEvent ev;
 	int w = win.w, h = win.h;
 	fd_set rfd;
-	int xfd = XConnectionNumber(xw.dpy), xev, blinkset = 0, dodraw = 0;
-	int ttyfd;
-	struct timespec drawtimeout, *tv = NULL, now, last, lastblink;
-	long deltatime;
+	int xfd = XConnectionNumber(xw.dpy), ttyfd, xev, drawing;
+	struct timespec seltv, *tv, now, lastblink, trigger;
+	double timeout;
 
 	/* Waiting for window mapping */
 	do {
@@ -1892,82 +2006,77 @@ run(void)
 	ttyfd = ttynew(opt_line, shell, opt_io, opt_cmd);
 	cresize(w, h);
 
-	clock_gettime(CLOCK_MONOTONIC, &last);
-	lastblink = last;
-
-	for (xev = actionfps;;) {
+	for (timeout = -1, drawing = 0, lastblink = (struct timespec){0};;) {
 		FD_ZERO(&rfd);
 		FD_SET(ttyfd, &rfd);
 		FD_SET(xfd, &rfd);
 
+		if (XPending(xw.dpy))
+			timeout = 0;  /* existing events might not set xfd */
+
+		seltv.tv_sec = timeout / 1E3;
+		seltv.tv_nsec = 1E6 * (timeout - 1E3 * seltv.tv_sec);
+		tv = timeout >= 0 ? &seltv : NULL;
+
 		if (pselect(MAX(xfd, ttyfd)+1, &rfd, NULL, NULL, tv, NULL) < 0) {
 			if (errno == EINTR)
 				continue;
 			die("select failed: %s\n", strerror(errno));
 		}
-		if (FD_ISSET(ttyfd, &rfd)) {
-			ttyread();
-			if (blinktimeout) {
-				blinkset = tattrset(ATTR_BLINK);
-				if (!blinkset)
-					MODBIT(win.mode, 0, MODE_BLINK);
-			}
-		}
-
-		if (FD_ISSET(xfd, &rfd))
-			xev = actionfps;
-
 		clock_gettime(CLOCK_MONOTONIC, &now);
-		drawtimeout.tv_sec = 0;
-		drawtimeout.tv_nsec =  (1000 * 1E6)/ xfps;
-		tv = &drawtimeout;
 
-		dodraw = 0;
-		if (blinktimeout && TIMEDIFF(now, lastblink) > blinktimeout) {
-			tsetdirtattr(ATTR_BLINK);
-			win.mode ^= MODE_BLINK;
-			lastblink = now;
-			dodraw = 1;
-		}
-		deltatime = TIMEDIFF(now, last);
-		if (deltatime > 1000 / (xev ? xfps : actionfps)) {
-			dodraw = 1;
-			last = now;
+		if (FD_ISSET(ttyfd, &rfd))
+			ttyread();
+
+		xev = 0;
+		while (XPending(xw.dpy)) {
+			xev = 1;
+			XNextEvent(xw.dpy, &ev);
+			if (XFilterEvent(&ev, None))
+				continue;
+			if (handler[ev.type])
+				(handler[ev.type])(&ev);
 		}
 
-		if (dodraw) {
-			while (XPending(xw.dpy)) {
-				XNextEvent(xw.dpy, &ev);
-				if (XFilterEvent(&ev, None))
-					continue;
-				if (handler[ev.type])
-					(handler[ev.type])(&ev);
+		/*
+		 * To reduce flicker and tearing, when new content or event
+		 * triggers drawing, we first wait a bit to ensure we got
+		 * everything, and if nothing new arrives - we draw.
+		 * We start with trying to wait minlatency ms. If more content
+		 * arrives sooner, we retry with shorter and shorter periods,
+		 * and eventually draw even without idle after maxlatency ms.
+		 * Typically this results in low latency while interacting,
+		 * maximum latency intervals during `cat huge.txt`, and perfect
+		 * sync with periodic updates from animations/key-repeats/etc.
+		 */
+		if (FD_ISSET(ttyfd, &rfd) || xev) {
+			if (!drawing) {
+				trigger = now;
+				drawing = 1;
 			}
+			timeout = (maxlatency - TIMEDIFF(now, trigger)) \
+			          / maxlatency * minlatency;
+			if (timeout > 0)
+				continue;  /* we have time, try to find idle */
+		}
 
-			draw();
-			XFlush(xw.dpy);
-
-			if (xev && !FD_ISSET(xfd, &rfd))
-				xev--;
-			if (!FD_ISSET(ttyfd, &rfd) && !FD_ISSET(xfd, &rfd)) {
-				if (blinkset) {
-					if (TIMEDIFF(now, lastblink) \
-							> blinktimeout) {
-						drawtimeout.tv_nsec = 1000;
-					} else {
-						drawtimeout.tv_nsec = (1E6 * \
-							(blinktimeout - \
-							TIMEDIFF(now,
-								lastblink)));
-					}
-					drawtimeout.tv_sec = \
-					    drawtimeout.tv_nsec / 1E9;
-					drawtimeout.tv_nsec %= (long)1E9;
-				} else {
-					tv = NULL;
-				}
+		/* idle detected or maxlatency exhausted -> draw */
+		timeout = -1;
+		if (blinktimeout && tattrset(ATTR_BLINK)) {
+			timeout = blinktimeout - TIMEDIFF(now, lastblink);
+			if (timeout <= 0) {
+				if (-timeout > blinktimeout) /* start visible */
+					win.mode |= MODE_BLINK;
+				win.mode ^= MODE_BLINK;
+				tsetdirtattr(ATTR_BLINK);
+				lastblink = now;
+				timeout = blinktimeout;
 			}
 		}
+
+		draw();
+		XFlush(xw.dpy);
+		drawing = 0;
 	}
 }
 
@@ -1984,20 +2093,12 @@ usage(void)
 	    " [stty_args ...]\n", argv0, argv0);
 }
 
-void setpalette(const Arg *arg) {
-    if ( arg->i < LEN(palettes) )   {
-        colorname = palettes[arg->i];
-        xloadcols();
-        cresize(win.w, win.h);
-    }
-}
-
 int
 main(int argc, char *argv[])
 {
 	xw.l = xw.t = 0;
 	xw.isfixed = False;
-	win.cursor = cursorshape;
+	xsetcursor(cursorshape);
 
 	ARGBEGIN {
 	case 'a':
@@ -2047,8 +2148,6 @@ main(int argc, char *argv[])
 	} ARGEND;
 
 run:
-    colorname = palettes[0];
-
 	if (argc > 0) /* eat all remaining arguments */
 		opt_cmd = argv;