Adding tagpreview patch (#271)

README.md

@@ -19,6 +19,9 @@ Browsing patches? There is a [map of patches](https://coggle.it/diagram/X9IiSSM6
 
 ### Changelog:
 
+
+2022-07-05 - Added the tagpreview patch
+
 2022-07-04 - Added the shift-tools patch(es) with individual toggles
 
 2022-06-20 - Added the renamed scratchpads patch
@@ -736,6 +739,9 @@ Browsing patches? There is a [map of patches](https://coggle.it/diagram/X9IiSSM6
    - [tagothermonitor](https://dwm.suckless.org/patches/tagothermonitor/)
       - adds functions and keybindings to tag a window to a desired tag on an adjacent monitor
 
+   - [tagpreview](https://dwm.suckless.org/patches/tag-previews/)
+      - shows a preview of a tag when hovering the tag icon using the mouse
+
    - [tagswapmon](https://github.com/bakkeby/patches/wiki/tagswapmon/)
       - swap all visible windows on one monitor with those of an adjacent monitor
 

config.def.h

@@ -11,6 +11,9 @@ static const unsigned int snap           = 32;  /* snap pixel */
 #if SWALLOW_PATCH
 static const int swallowfloating         = 0;   /* 1 means swallow floating windows by default */
 #endif // SWALLOW_PATCH
+#if BAR_TAGPREVIEW_PATCH
+static const int scalepreview            = 4;        /* Tag preview scaling */
+#endif // BAR_TAGPREVIEW_PATCH
 #if NO_MOD_BUTTONS_PATCH
 static int nomodbuttons                  = 1;   /* allow client mouse button bindings that have no modifier */
 #endif // NO_MOD_BUTTONS_PATCH
@@ -504,80 +507,80 @@ static const Inset default_inset = {
  *    name - does nothing, intended for visual clue and for logging / debugging
  */
 static const BarRule barrules[] = {
-	/* monitor   bar    alignment         widthfunc                drawfunc                clickfunc                name */
+	/* monitor   bar    alignment         widthfunc                 drawfunc                clickfunc                hoverfunc                name */
 	#if BAR_STATUSBUTTON_PATCH
-	{ -1,        0,     BAR_ALIGN_LEFT,   width_stbutton,          draw_stbutton,          click_stbutton,          "statusbutton" },
+	{ -1,        0,     BAR_ALIGN_LEFT,   width_stbutton,           draw_stbutton,          click_stbutton,          NULL,                    "statusbutton" },
 	#endif // BAR_STATUSBUTTON_PATCH
 	#if BAR_POWERLINE_TAGS_PATCH
-	{  0,        0,     BAR_ALIGN_LEFT,   width_pwrl_tags,         draw_pwrl_tags,         click_pwrl_tags,         "powerline_tags" },
+	{  0,        0,     BAR_ALIGN_LEFT,   width_pwrl_tags,          draw_pwrl_tags,         click_pwrl_tags,         NULL,                    "powerline_tags" },
 	#endif // BAR_POWERLINE_TAGS_PATCH
 	#if BAR_TAGS_PATCH
-	{ -1,        0,     BAR_ALIGN_LEFT,   width_tags,              draw_tags,              click_tags,              "tags" },
+	{ -1,        0,     BAR_ALIGN_LEFT,   width_tags,               draw_tags,              click_tags,              hover_tags,              "tags" },
 	#endif // BAR_TAGS_PATCH
 	#if BAR_TAGLABELS_PATCH
-	{ -1,        0,     BAR_ALIGN_LEFT,   width_taglabels,         draw_taglabels,         click_taglabels,         "taglabels" },
+	{ -1,        0,     BAR_ALIGN_LEFT,   width_taglabels,          draw_taglabels,         click_taglabels,         NULL,                    "taglabels" },
 	#endif // BAR_TAGLABELS_PATCH
 	#if BAR_TAGGRID_PATCH
-	{ -1,        0,     BAR_ALIGN_LEFT,   width_taggrid,           draw_taggrid,           click_taggrid,           "taggrid" },
+	{ -1,        0,     BAR_ALIGN_LEFT,   width_taggrid,            draw_taggrid,           click_taggrid,           NULL,                    "taggrid" },
 	#endif // BAR_TAGGRID_PATCH
 	#if BAR_SYSTRAY_PATCH
-	{  0,        0,     BAR_ALIGN_RIGHT,  width_systray,           draw_systray,           click_systray,           "systray" },
+	{  0,        0,     BAR_ALIGN_RIGHT,  width_systray,            draw_systray,           click_systray,           NULL,                    "systray" },
 	#endif // BAR_SYSTRAY_PATCH
 	#if BAR_LTSYMBOL_PATCH
-	{ -1,        0,     BAR_ALIGN_LEFT,   width_ltsymbol,          draw_ltsymbol,          click_ltsymbol,          "layout" },
+	{ -1,        0,     BAR_ALIGN_LEFT,   width_ltsymbol,           draw_ltsymbol,          click_ltsymbol,          NULL,                    "layout" },
 	#endif // BAR_LTSYMBOL_PATCH
 	#if BAR_STATUSCOLORS_PATCH && BAR_STATUSCMD_PATCH
-	{ statusmon, 0,     BAR_ALIGN_RIGHT,  width_statuscolors,      draw_statuscolors,      click_statuscmd,         "statuscolors" },
+	{ statusmon, 0,     BAR_ALIGN_RIGHT,  width_statuscolors,       draw_statuscolors,      click_statuscmd,         NULL,                    "statuscolors" },
 	#elif BAR_STATUSCOLORS_PATCH
-	{ statusmon, 0,     BAR_ALIGN_RIGHT,  width_statuscolors,      draw_statuscolors,      click_statuscolors,      "statuscolors" },
+	{ statusmon, 0,     BAR_ALIGN_RIGHT,  width_statuscolors,       draw_statuscolors,      click_statuscolors,      NULL,                    "statuscolors" },
 	#elif BAR_STATUS2D_PATCH && BAR_STATUSCMD_PATCH
-	{ statusmon, 0,     BAR_ALIGN_RIGHT,  width_status2d,          draw_status2d,          click_statuscmd,         "status2d" },
+	{ statusmon, 0,     BAR_ALIGN_RIGHT,  width_status2d,           draw_status2d,          click_statuscmd,         NULL,                    "status2d" },
 	#elif BAR_STATUS2D_PATCH
-	{ statusmon, 0,     BAR_ALIGN_RIGHT,  width_status2d,          draw_status2d,          click_status2d,          "status2d" },
+	{ statusmon, 0,     BAR_ALIGN_RIGHT,  width_status2d,           draw_status2d,          click_status2d,          NULL,                    "status2d" },
 	#elif BAR_POWERLINE_STATUS_PATCH
-	{ statusmon, 0,     BAR_ALIGN_RIGHT,  width_pwrl_status,       draw_pwrl_status,       click_pwrl_status,       "powerline_status" },
+	{ statusmon, 0,     BAR_ALIGN_RIGHT,  width_pwrl_status,        draw_pwrl_status,       click_pwrl_status,       NULL,                    "powerline_status" },
 	#elif BAR_STATUS_PATCH && BAR_STATUSCMD_PATCH
-	{ statusmon, 0,     BAR_ALIGN_RIGHT,  width_status,            draw_status,            click_statuscmd,         "status" },
+	{ statusmon, 0,     BAR_ALIGN_RIGHT,  width_status,             draw_status,            click_statuscmd,         NULL,                    "status" },
 	#elif BAR_STATUS_PATCH
-	{ statusmon, 0,     BAR_ALIGN_RIGHT,  width_status,            draw_status,            click_status,            "status" },
+	{ statusmon, 0,     BAR_ALIGN_RIGHT,  width_status,             draw_status,            click_status,            NULL,                    "status" },
 	#endif // BAR_STATUS2D_PATCH | BAR_STATUSCMD_PATCH
 	#if XKB_PATCH
-	{  0,        0,     BAR_ALIGN_RIGHT,  width_xkb,               draw_xkb,               click_xkb,               "xkb" },
+	{  0,        0,     BAR_ALIGN_RIGHT,  width_xkb,                draw_xkb,               click_xkb,               NULL,                    "xkb" },
 	#endif // XKB_PATCH
 	#if BAR_FLEXWINTITLE_PATCH
-	{ -1,        0,     BAR_ALIGN_NONE,   width_flexwintitle,      draw_flexwintitle,      click_flexwintitle,      "flexwintitle" },
+	{ -1,        0,     BAR_ALIGN_NONE,   width_flexwintitle,       draw_flexwintitle,      click_flexwintitle,      NULL,                    "flexwintitle" },
 	#elif BAR_TABGROUPS_PATCH
-	{ -1,        0,     BAR_ALIGN_NONE,   width_bartabgroups,      draw_bartabgroups,      click_bartabgroups,      "bartabgroups" },
+	{ -1,        0,     BAR_ALIGN_NONE,   width_bartabgroups,       draw_bartabgroups,      click_bartabgroups,      NULL,                    "bartabgroups" },
 	#elif BAR_AWESOMEBAR_PATCH
-	{ -1,        0,     BAR_ALIGN_NONE,   width_awesomebar,        draw_awesomebar,        click_awesomebar,        "awesomebar" },
+	{ -1,        0,     BAR_ALIGN_NONE,   width_awesomebar,         draw_awesomebar,        click_awesomebar,        NULL,                    "awesomebar" },
 	#elif BAR_FANCYBAR_PATCH
-	{ -1,        0,     BAR_ALIGN_NONE,   width_fancybar,          draw_fancybar,          click_fancybar,          "fancybar" },
+	{ -1,        0,     BAR_ALIGN_NONE,   width_fancybar,           draw_fancybar,          click_fancybar,          NULL,                    "fancybar" },
 	#elif BAR_WINTITLE_PATCH
-	{ -1,        0,     BAR_ALIGN_NONE,   width_wintitle,          draw_wintitle,          click_wintitle,          "wintitle" },
+	{ -1,        0,     BAR_ALIGN_NONE,   width_wintitle,           draw_wintitle,          click_wintitle,          NULL,                    "wintitle" },
 	#endif // BAR_TABGROUPS_PATCH | BAR_AWESOMEBAR_PATCH | BAR_FANCYBAR_PATCH | BAR_WINTITLE_PATCH
 	#if BAR_EXTRASTATUS_PATCH
 	#if BAR_STATUSCOLORS_PATCH && BAR_STATUSCMD_PATCH
-	{ statusmon, 1,     BAR_ALIGN_CENTER, width_statuscolors_es,   draw_statuscolors_es,   click_statuscmd_es,      "statuscolors_es" },
+	{ statusmon, 1,     BAR_ALIGN_CENTER, width_statuscolors_es,    draw_statuscolors_es,   click_statuscmd_es,      NULL,                    "statuscolors_es" },
 	#elif BAR_STATUSCOLORS_PATCH
-	{ statusmon, 1,     BAR_ALIGN_CENTER, width_statuscolors_es,   draw_statuscolors_es,   click_statuscolors,      "statuscolors_es" },
+	{ statusmon, 1,     BAR_ALIGN_CENTER, width_statuscolors_es,    draw_statuscolors_es,   click_statuscolors,      NULL,                    "statuscolors_es" },
 	#elif BAR_STATUS2D_PATCH && BAR_STATUSCMD_PATCH
-	{ statusmon, 1,     BAR_ALIGN_CENTER, width_status2d_es,       draw_status2d_es,       click_statuscmd_es,      "status2d_es" },
+	{ statusmon, 1,     BAR_ALIGN_CENTER, width_status2d_es,        draw_status2d_es,       click_statuscmd_es,      NULL,                    "status2d_es" },
 	#elif BAR_STATUS2D_PATCH
-	{ statusmon, 1,     BAR_ALIGN_CENTER, width_status2d_es,       draw_status2d_es,       click_status2d,          "status2d_es" },
+	{ statusmon, 1,     BAR_ALIGN_CENTER, width_status2d_es,        draw_status2d_es,       click_status2d,          NULL,                    "status2d_es" },
 	#elif BAR_POWERLINE_STATUS_PATCH
-	{ statusmon, 1,     BAR_ALIGN_RIGHT,  width_pwrl_status_es,    draw_pwrl_status_es,    click_pwrl_status,       "powerline_status" },
+	{ statusmon, 1,     BAR_ALIGN_RIGHT,  width_pwrl_status_es,     draw_pwrl_status_es,    click_pwrl_status,       NULL,                    "powerline_status" },
 	#elif BAR_STATUSCMD_PATCH && BAR_STATUS_PATCH
-	{ statusmon, 1,     BAR_ALIGN_CENTER, width_status_es,         draw_status_es,         click_statuscmd_es,      "status_es" },
+	{ statusmon, 1,     BAR_ALIGN_CENTER, width_status_es,          draw_status_es,         click_statuscmd_es,      NULL,                    "status_es" },
 	#elif BAR_STATUS_PATCH
-	{ statusmon, 1,     BAR_ALIGN_CENTER, width_status_es,         draw_status_es,         click_status,            "status_es" },
+	{ statusmon, 1,     BAR_ALIGN_CENTER, width_status_es,          draw_status_es,         click_status,            NULL,                    "status_es" },
 	#endif // BAR_STATUS2D_PATCH | BAR_STATUSCMD_PATCH
 	#endif // BAR_EXTRASTATUS_PATCH
 	#if BAR_FLEXWINTITLE_PATCH
 	#if BAR_WINTITLE_HIDDEN_PATCH
-	{ -1,        1,  BAR_ALIGN_RIGHT_RIGHT, width_wintitle_hidden, draw_wintitle_hidden,   click_wintitle_hidden,   "wintitle_hidden" },
+	{ -1,        1,  BAR_ALIGN_RIGHT_RIGHT, width_wintitle_hidden,  draw_wintitle_hidden,   click_wintitle_hidden,   NULL,                    "wintitle_hidden" },
 	#endif
 	#if BAR_WINTITLE_FLOATING_PATCH
-	{ -1,        1,     BAR_ALIGN_LEFT,   width_wintitle_floating, draw_wintitle_floating, click_wintitle_floating, "wintitle_floating" },
+	{ -1,        1,     BAR_ALIGN_LEFT,   width_wintitle_floating,  draw_wintitle_floating, click_wintitle_floating, NULL,                    "wintitle_floating" },
 	#endif // BAR_WINTITLE_FLOATING_PATCH
 	#endif // BAR_FLEXWINTITLE_PATCH
 };

config.mk

@@ -48,7 +48,7 @@ FREETYPEINC = /usr/include/freetype2
 # Uncomment this for the swallow patch / SWALLOW_PATCH
 #XCBLIBS = -lX11-xcb -lxcb -lxcb-res
 
-# This is needed for the winicon patch / BAR_WINICON_PATCH
+# This is needed for the winicon and tagpreview patches / BAR_WINICON_PATCH / BAR_TAGPREVIEW_PATCH
 #IMLIB2LIBS = -lImlib2
 
 # includes and libs

dwm.c

@@ -314,6 +314,7 @@ typedef struct {
 	int (*widthfunc)(Bar *bar, BarArg *a);
 	int (*drawfunc)(Bar *bar, BarArg *a);
 	int (*clickfunc)(Bar *bar, Arg *arg, BarArg *a);
+	int (*hoverfunc)(Bar *bar, BarArg *a, XMotionEvent *ev);
 	char *name; // for debugging
 	int x, w; // position, width for internal use
 } BarRule;
@@ -515,6 +516,11 @@ struct Monitor {
 	Client *lastsel;
 	const Layout *lastlt;
 	#endif // IPC_PATCH
+	#if BAR_TAGPREVIEW_PATCH
+	Window tagwin;
+	int previewshow;
+	Pixmap tagmap[NUMTAGS];
+	#endif // BAR_TAGPREVIEW_PATCH
 };
 
 typedef struct {
@@ -1308,6 +1314,13 @@ cleanupmon(Monitor *mon)
 	#if PERTAG_PATCH
 	free(mon->pertag);
 	#endif // PERTAG_PATCH
+	#if BAR_TAGPREVIEW_PATCH
+	for (size_t i = 0; i < NUMTAGS; i++)
+		if (mon->tagmap[i])
+			XFreePixmap(dpy, mon->tagmap[i]);
+	XUnmapWindow(dpy, mon->tagwin);
+	XDestroyWindow(dpy, mon->tagwin);
+	#endif // BAR_TAGPREVIEW_PATCH
 	free(mon);
 }
 
@@ -2621,11 +2634,22 @@ motionnotify(XEvent *e)
 {
 	static Monitor *mon = NULL;
 	Monitor *m;
+	Bar *bar;
 	#if LOSEFULLSCREEN_PATCH
 	Client *sel;
 	#endif // LOSEFULLSCREEN_PATCH
 	XMotionEvent *ev = &e->xmotion;
 
+	if ((bar = wintobar(ev->window))) {
+		barhover(e, bar);
+		return;
+	}
+
+	#if BAR_TAGPREVIEW_PATCH
+	if (selmon->previewshow != 0)
+		hidetagpreview(selmon);
+	#endif // BAR_TAGPREVIEW_PATCH
+
 	if (ev->window != root)
 		return;
 	if ((m = recttomon(ev->x_root, ev->y_root, 1, 1)) != mon && mon) {
@@ -3732,6 +3756,9 @@ setup(void)
 
 	updatebars();
 	updatestatus();
+	#if BAR_TAGPREVIEW_PATCH
+	updatepreview();
+	#endif // BAR_TAGPREVIEW_PATCH
 
 	/* supporting window for NetWMCheck */
 	wmcheckwin = XCreateSimpleWindow(dpy, root, 0, 0, 1, 1, 0, 0, 0);
@@ -4198,6 +4225,9 @@ toggleview(const Arg *arg)
 	#if !EMPTYVIEW_PATCH
 	if (newtagset) {
 	#endif // EMPTYVIEW_PATCH
+		#if BAR_TAGPREVIEW_PATCH
+		tagpreviewswitchtag();
+		#endif // BAR_TAGPREVIEW_PATCH
 		selmon->tagset[selmon->seltags] = newtagset;
 
 		#if PERTAG_PATCH
@@ -4421,7 +4451,11 @@ updatebars(void)
 		#else
 		.background_pixmap = ParentRelative,
 		#endif // BAR_ALPHA_PATCH
+		#if BAR_TAGPREVIEW_PATCH
+		.event_mask = ButtonPressMask|ExposureMask|PointerMotionMask
+		#else
 		.event_mask = ButtonPressMask|ExposureMask
+		#endif // BAR_TAGPREVIEW_PATCH
 	};
 	XClassHint ch = {"dwm", "dwm"};
 	for (m = mons; m; m = m->next) {
@@ -4828,6 +4862,9 @@ view(const Arg *arg)
 		#endif // TOGGLETAG_PATCH
 		return;
 	}
+	#if BAR_TAGPREVIEW_PATCH
+	tagpreviewswitchtag();
+	#endif // BAR_TAGPREVIEW_PATCH
 	selmon->seltags ^= 1; /* toggle sel tagset */
 	#if PERTAG_PATCH
 	pertagview(arg);

patch/bar.c

@@ -0,0 +1,39 @@
+void
+barhover(XEvent *e, Bar *bar)
+{
+	const BarRule *br;
+	Monitor *m = bar->mon;
+	XMotionEvent *ev = &e->xmotion;
+	BarArg barg = { 0, 0, 0, 0 };
+	int r;
+
+	for (r = 0; r < LENGTH(barrules); r++) {
+		br = &barrules[r];
+		if (br->bar != bar->idx || (br->monitor == 'A' && m != selmon) || br->hoverfunc == NULL)
+			continue;
+		if (br->monitor != 'A' && br->monitor != -1 && br->monitor != bar->mon->num)
+			continue;
+		if (bar->x[r] > ev->x || ev->x > bar->x[r] + bar->w[r])
+			continue;
+
+		barg.x = ev->x - bar->x[r];
+		barg.y = ev->y - bar->borderpx;
+		barg.w = bar->w[r];
+		barg.h = bar->bh - 2 * bar->borderpx;
+
+		br->hoverfunc(bar, &barg, ev);
+		break;
+	}
+}
+
+Bar *
+wintobar(Window win)
+{
+	Monitor *m;
+	Bar *bar;
+	for (m = mons; m; m = m->next)
+		for (bar = m->bar; bar; bar = bar->next)
+			if (bar->win == win)
+				return bar;
+	return NULL;
+}

patch/bar.h

@@ -0,0 +1,2 @@
+static void barhover(XEvent *e, Bar *bar);
+static Bar *wintobar(Window win);

patch/bar_tagpreview.c

@@ -0,0 +1,95 @@
+#include <Imlib2.h>
+
+void
+showtagpreview(int tag, int x, int y)
+{
+	if (selmon->tagmap[tag]) {
+		XSetWindowBackgroundPixmap(dpy, selmon->tagwin, selmon->tagmap[tag]);
+		XCopyArea(dpy, selmon->tagmap[tag], selmon->tagwin, drw->gc, 0, 0, selmon->mw / scalepreview, selmon->mh / scalepreview, 0, 0);
+		XMoveWindow(dpy, selmon->tagwin, x, y);
+		XSync(dpy, False);
+		XMapWindow(dpy, selmon->tagwin);
+	} else
+		XUnmapWindow(dpy, selmon->tagwin);
+}
+
+void
+hidetagpreview(Monitor *m)
+{
+	m->previewshow = 0;
+	XUnmapWindow(dpy, m->tagwin);
+}
+
+void
+tagpreviewswitchtag(void)
+{
+	int i;
+	unsigned int occ = 0;
+	Client *c;
+	Imlib_Image image;
+
+	for (c = selmon->clients; c; c = c->next)
+		occ |= c->tags;
+	for (i = 0; i < NUMTAGS; i++) {
+		if (selmon->tagset[selmon->seltags] & 1 << i) {
+					if (selmon->tagmap[i] != 0) {
+				XFreePixmap(dpy, selmon->tagmap[i]);
+				selmon->tagmap[i] = 0;
+			}
+			if (occ & 1 << i) {
+				image = imlib_create_image(sw, sh);
+				imlib_context_set_image(image);
+				imlib_context_set_display(dpy);
+				#if BAR_ALPHA_PATCH
+				imlib_image_set_has_alpha(1);
+				imlib_context_set_blend(0);
+				imlib_context_set_visual(visual);
+				#else
+				imlib_context_set_visual(DefaultVisual(dpy, screen));
+				#endif // BAR_ALPHA_PATCH
+				imlib_context_set_drawable(root);
+				imlib_copy_drawable_to_image(0, selmon->mx, selmon->my, selmon->mw ,selmon->mh, 0, 0, 1);
+				#if BAR_ALPHA_PATCH
+				selmon->tagmap[i] = XCreatePixmap(dpy, selmon->tagwin, selmon->mw / scalepreview, selmon->mh / scalepreview, depth);
+				#else
+				selmon->tagmap[i] = XCreatePixmap(dpy, selmon->tagwin, selmon->mw / scalepreview, selmon->mh / scalepreview, DefaultDepth(dpy, screen));
+				#endif // BAR_ALPHA_PATCH
+				imlib_context_set_drawable(selmon->tagmap[i]);
+				imlib_render_image_part_on_drawable_at_size(0, 0, selmon->mw, selmon->mh, 0, 0, selmon->mw / scalepreview, selmon->mh / scalepreview);
+				imlib_free_image();
+			}
+		}
+	}
+}
+
+void
+updatepreview(void)
+{
+	Monitor *m;
+
+	XSetWindowAttributes wa = {
+		.override_redirect = True,
+		#if BAR_ALPHA_PATCH
+		.background_pixel = 0,
+		.border_pixel = 0,
+		.colormap = cmap,
+		#else
+		.background_pixmap = ParentRelative,
+		#endif // BAR_ALPHA_PATCH
+		.event_mask = ButtonPressMask|ExposureMask
+	};
+	for (m = mons; m; m = m->next) {
+		m->tagwin = XCreateWindow(dpy, root, m->wx, m->bar->by + bh, m->mw / 4, m->mh / 4, 0,
+				#if BAR_ALPHA_PATCH
+				depth, CopyFromParent, visual,
+				CWOverrideRedirect|CWBackPixel|CWBorderPixel|CWColormap|CWEventMask, &wa
+				#else
+				DefaultDepth(dpy, screen), CopyFromParent, DefaultVisual(dpy, screen),
+				CWOverrideRedirect|CWBackPixmap|CWEventMask, &wa
+				#endif // BAR_ALPHA_PATCH
+				);
+		XDefineCursor(dpy, m->tagwin, cursor[CurNormal]->cursor);
+		XMapRaised(dpy, m->tagwin);
+		XUnmapWindow(dpy, m->tagwin);
+	}
+}

patch/bar_tagpreview.h

@@ -0,0 +1,4 @@
+static void showtagpreview(int tag, int x, int y);
+static void hidetagpreview(Monitor *m);
+static void tagpreviewswitchtag(void);
+static void updatepreview(void);

patch/bar_tags.c

@@ -91,3 +91,56 @@ click_tags(Bar *bar, Arg *arg, BarArg *a)
 	return ClkTagBar;
 }
 
+int
+hover_tags(Bar *bar, BarArg *a, XMotionEvent *ev)
+{
+	#if BAR_TAGPREVIEW_PATCH
+	int i = 0, x = lrpad / 2;
+	int px, py;
+	Monitor *m = bar->mon;
+	#if VANITYGAPS_PATCH
+	int ov = gappov;
+	int oh = gappoh;
+	#else
+	int ov = 0;
+	int oh = 0;
+	#endif // VANITYGAPS_PATCH
+
+	#if BAR_HIDEVACANTTAGS_PATCH
+	Client *c;
+	unsigned int occ = 0;
+	for (c = bar->mon->clients; c; c = c->next)
+		occ |= c->tags == 255 ? 0 : c->tags;
+	#endif // BAR_HIDEVACANTTAGS_PATCH
+
+	do {
+		#if BAR_HIDEVACANTTAGS_PATCH
+		if (!(occ & 1 << i || bar->mon->tagset[bar->mon->seltags] & 1 << i))
+			continue;
+		#endif // BAR_HIDEVACANTTAGS_PATCH
+		x += TEXTW(tagicon(bar->mon, i));
+	} while (a->x >= x && ++i < NUMTAGS);
+
+	if (i < NUMTAGS) {
+		if ((i + 1) != selmon->previewshow && !(selmon->tagset[selmon->seltags] & 1 << i)) {
+			if (bar->by > m->my + m->mh / 2) // bottom bar
+				py = bar->by - m->mh / scalepreview - oh;
+			else // top bar
+				py = bar->by + bar->bh + oh;
+			px = bar->bx + ev->x - m->mw / scalepreview / 2;
+			if (px + m->mw / scalepreview > m->mx + m->mw)
+				px = m->wx + m->ww - m->mw / scalepreview - ov;
+			else if (px < bar->bx)
+				px = m->wx + ov;
+			selmon->previewshow = i + 1;
+			showtagpreview(i, px, py);
+		} else if (selmon->tagset[selmon->seltags] & 1 << i) {
+			hidetagpreview(selmon);
+		}
+	} else if (selmon->previewshow != 0) {
+		hidetagpreview(selmon);
+	}
+	#endif // BAR_TAGPREVIEW_PATCH
+
+	return 1;
+}

patch/bar_tags.h

@@ -1,4 +1,4 @@
 static int width_tags(Bar *bar, BarArg *a);
 static int draw_tags(Bar *bar, BarArg *a);
 static int click_tags(Bar *bar, Arg *arg, BarArg *a);
-
+static int hover_tags(Bar *bar, BarArg *a, XMotionEvent *ev);

patch/include.c

@@ -1,6 +1,7 @@
 /* Bar functionality */
 #include "bar_indicators.c"
 #include "bar_tagicons.c"
+#include "bar.c"
 
 #if BAR_ALPHA_PATCH
 #include "bar_alpha.c"
@@ -50,6 +51,9 @@
 #if BAR_TABGROUPS_PATCH
 #include "bar_tabgroups.c"
 #endif
+#if BAR_TAGPREVIEW_PATCH
+#include "bar_tagpreview.c"
+#endif
 #if BAR_TAGS_PATCH
 #include "bar_tags.c"
 #endif

patch/include.h

@@ -1,6 +1,7 @@
 /* Bar functionality */
 #include "bar_indicators.h"
 #include "bar_tagicons.h"
+#include "bar.h"
 
 #if BAR_ALPHA_PATCH
 #include "bar_alpha.h"
@@ -59,6 +60,9 @@
 #if BAR_TAGLABELS_PATCH
 #include "bar_taglabels.h"
 #endif
+#if BAR_TAGPREVIEW_PATCH
+#include "bar_tagpreview.h"
+#endif
 #if BAR_TAGGRID_PATCH
 #include "bar_taggrid.h"
 #endif

patches.def.h

@@ -115,6 +115,23 @@
  */
 #define BAR_TAGGRID_PATCH 0
 
+/* Hover tag icons to see a preview of the windows on that tag.
+ *
+ * The patch depends on Imlib2 for icon scaling.
+ * You need to uncomment the corresponding line in config.mk to use the -lImlib2 library
+ *
+ * Arch Linux:
+ *     sudo pacman -S imlib2
+ * Debian:
+ *     sudo apt install libimlib2-dev
+ *
+ * As with the winicon patch you may want to consider adding the compiler flags of -O3 and
+ * -march=native to enable auto loop vectorize for better performance.
+ *
+ * https://dwm.suckless.org/patches/tag-previews/
+ */
+#define BAR_TAGPREVIEW_PATCH 0
+
 /* Show status in bar */
 #define BAR_STATUS_PATCH 1