client-opacity-focus.patch

From 694751a31a437bbb28c3a75c917ed922231ab366 Mon Sep 17 00:00:00 2001
From: Hans von Hohenstaufen <Hans.von.Hohenstaufen@protonmail.com>
Date: Mon, 22 Dec 2025 01:43:50 +0000
Subject: [PATCH] Add client opacity focus

---
 config.def.h | 12 +++++++---
 dwl.c        | 63 ++++++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 72 insertions(+), 3 deletions(-)

diff --git a/config.def.h b/config.def.h
index 95c2afa..b7002f5 100644
--- a/config.def.h
+++ b/config.def.h
@@ -13,6 +13,8 @@ static const float focuscolor[]            = COLOR(0x005577ff);
 static const float urgentcolor[]           = COLOR(0xff0000ff);
 /* This conforms to the xdg-protocol. Set the alpha to zero to restore the old behavior */
 static const float fullscreen_bg[]         = {0.0f, 0.0f, 0.0f, 1.0f}; /* You can also use glsl colors */
+static const float default_opacity_unfocus = 0.70f;
+static const float default_opacity_focus   = 1.00f;
 
 /* tagging - TAGCOUNT must be no greater than 31 */
 #define TAGCOUNT (9)
@@ -22,10 +24,10 @@ static int log_level = WLR_ERROR;
 
 /* NOTE: ALWAYS keep a rule declared even if you don't use rules (e.g leave at least one example) */
 static const Rule rules[] = {
-	/* app_id             title       tags mask     isfloating   monitor */
+	/* app_id             title       tags mask     isfloating   alpha unfocus      monitor */
 	/* examples: */
-	{ "Gimp_EXAMPLE",     NULL,       0,            1,           -1 }, /* Start on currently visible tags floating, not tiled */
-	{ "firefox_EXAMPLE",  NULL,       1 << 8,       0,           -1 }, /* Start on ONLY tag "9" */
+	{ "Gimp_EXAMPLE",     NULL,       0,            1,           default_opacity_unfocus, -1 }, /* Start on currently visible tags floating, not tiled */
+	{ "firefox_EXAMPLE",  NULL,       1 << 8,       0,           1.00,                    -1 }, /* Start on ONLY tag "9" */
 };
 
 /* layout(s) */
@@ -139,6 +141,10 @@ static const Key keys[] = {
 	{ MODKEY,                    XKB_KEY_t,          setlayout,      {.v = &layouts[0]} },
 	{ MODKEY,                    XKB_KEY_f,          setlayout,      {.v = &layouts[1]} },
 	{ MODKEY,                    XKB_KEY_m,          setlayout,      {.v = &layouts[2]} },
+	{ MODKEY|WLR_MODIFIER_CTRL,  XKB_KEY_k,          setopacityunfocus, {.f = +0.1f} },
+	{ MODKEY|WLR_MODIFIER_CTRL,  XKB_KEY_j,          setopacityunfocus, {.f = -0.1f} },
+	{ MODKEY|WLR_MODIFIER_CTRL|WLR_MODIFIER_SHIFT, XKB_KEY_K, setopacityfocus, {.f = +0.1f} },
+	{ MODKEY|WLR_MODIFIER_CTRL|WLR_MODIFIER_SHIFT, XKB_KEY_J, setopacityfocus, {.f = -0.1f} },
 	{ MODKEY,                    XKB_KEY_space,      setlayout,      {0} },
 	{ MODKEY|WLR_MODIFIER_SHIFT, XKB_KEY_space,      togglefloating, {0} },
 	{ MODKEY,                    XKB_KEY_e,         togglefullscreen, {0} },
diff --git a/dwl.c b/dwl.c
index 12f441e..7539738 100644
--- a/dwl.c
+++ b/dwl.c
@@ -138,6 +138,9 @@ typedef struct {
 	unsigned int bw;
 	uint32_t tags;
 	int isfloating, isurgent, isfullscreen;
+	float opacity;
+	float opacity_focus;
+	float opacity_unfocus;
 	uint32_t resize; /* configure serial of a pending resize */
 } Client;
 
@@ -227,6 +230,7 @@ typedef struct {
 	const char *title;
 	uint32_t tags;
 	int isfloating;
+	float opacity_unfocus;
 	int monitor;
 } Rule;
 
@@ -319,6 +323,7 @@ static void requeststartdrag(struct wl_listener *listener, void *data);
 static void requestmonstate(struct wl_listener *listener, void *data);
 static void resize(Client *c, struct wlr_box geo, int interact);
 static void run(char *startup_cmd);
+static void scenebuffersetopacity(struct wlr_scene_buffer *buffer, int sx, int sy, void *user_data);
 static void setcursor(struct wl_listener *listener, void *data);
 static void setcursorshape(struct wl_listener *listener, void *data);
 static void setfloating(Client *c, int floating);
@@ -326,6 +331,8 @@ static void setfullscreen(Client *c, int fullscreen);
 static void setlayout(const Arg *arg);
 static void setmfact(const Arg *arg);
 static void setmon(Client *c, Monitor *m, uint32_t newtags);
+static void setopacityunfocus(const Arg *arg);
+static void setopacityfocus(const Arg *arg);
 static void setpsel(struct wl_listener *listener, void *data);
 static void setsel(struct wl_listener *listener, void *data);
 static void setup(void);
@@ -490,6 +497,7 @@ applyrules(Client *c)
 		if ((!r->title || strstr(title, r->title))
 				&& (!r->id || strstr(appid, r->id))) {
 			c->isfloating = r->isfloating;
+			c->opacity = r->opacity_unfocus;
 			newtags |= r->tags;
 			i = 0;
 			wl_list_for_each(m, &mons, link) {
@@ -1127,6 +1135,10 @@ createnotify(struct wl_listener *listener, void *data)
 	c = toplevel->base->data = ecalloc(1, sizeof(*c));
 	c->surface.xdg = toplevel->base;
 	c->bw = borderpx;
+	/* Set default opacity*/
+	c->opacity_unfocus = default_opacity_unfocus;
+	c->opacity_focus = default_opacity_focus;
+	c->opacity = default_opacity_unfocus;
 
 	LISTEN(&toplevel->base->surface->events.commit, &c->commit, commitnotify);
 	LISTEN(&toplevel->base->surface->events.map, &c->map, mapnotify);
@@ -1429,6 +1441,7 @@ focusclient(Client *c, int lift)
 		wl_list_insert(&fstack, &c->flink);
 		selmon = c->mon;
 		c->isurgent = 0;
+		c->opacity = c->opacity_focus;
 
 		/* Don't change border color if there is an exclusive focus or we are
 		 * handling a drag operation */
@@ -1453,6 +1466,7 @@ focusclient(Client *c, int lift)
 			client_set_border_color(old_c, bordercolor);
 
 			client_activate_surface(old, 0);
+			old_c->opacity = old_c->opacity_unfocus;
 		}
 	}
 	printstatus();
@@ -2159,6 +2173,7 @@ rendermon(struct wl_listener *listener, void *data)
 	/* Render if no XDG clients have an outstanding resize and are visible on
 	 * this monitor. */
 	wl_list_for_each(c, &clients, link) {
+		wlr_scene_node_for_each_buffer(&c->scene_surface->node, scenebuffersetopacity, c);
 		if (c->resize && !c->isfloating && client_is_rendered_on_mon(c, m) && !client_is_stopped(c))
 			goto skip;
 	}
@@ -2295,6 +2310,15 @@ run(char *startup_cmd)
 	wl_display_run(dpy);
 }
 
+void
+scenebuffersetopacity(struct wlr_scene_buffer *buffer, int sx, int sy, void *data)
+{
+	Client *c = data;
+	/* xdg-popups are children of Client.scene, we do not have to worry about
+	 * messing with them. */
+	wlr_scene_buffer_set_opacity(buffer, c->isfullscreen ? 1 : c->opacity);
+}
+
 void
 setcursor(struct wl_listener *listener, void *data)
 {
@@ -2363,6 +2387,7 @@ setfullscreen(Client *c, int fullscreen)
 		 * client positions are set by the user and cannot be recalculated */
 		resize(c, c->prev, 0);
 	}
+	wlr_scene_node_for_each_buffer(&c->scene_surface->node, scenebuffersetopacity, c);
 	arrange(c->mon);
 	printstatus();
 }
@@ -2419,6 +2444,44 @@ setmon(Client *c, Monitor *m, uint32_t newtags)
 	focusclient(focustop(selmon), 1);
 }
 
+
+void
+setopacityunfocus(const Arg *arg)
+{
+	Client *sel = focustop(selmon);
+	if (!sel)
+		return;
+
+	sel->opacity_unfocus += arg->f;
+	if (sel->opacity_unfocus > 1.0)
+		sel->opacity_unfocus = 1.0f;
+
+	if (sel->opacity_unfocus < 0.1)
+		sel->opacity_unfocus = 0.1f;
+
+	wlr_scene_node_for_each_buffer(&sel->scene_surface->node, scenebuffersetopacity, sel);
+}
+
+void
+setopacityfocus(const Arg *arg)
+{
+	Client *sel = focustop(selmon);
+	if (!sel)
+		return;
+
+	sel->opacity_focus += arg->f;
+	if (sel->opacity_focus > 1.0)
+		sel->opacity_focus = 1.0f;
+
+	if (sel->opacity_focus < 0.1)
+		sel->opacity_focus = 0.1f;
+
+	/* Change opacity from current client */
+	sel->opacity = sel->opacity_focus;
+
+	wlr_scene_node_for_each_buffer(&sel->scene_surface->node, scenebuffersetopacity, sel);
+}
+
 void
 setpsel(struct wl_listener *listener, void *data)
 {
-- 
2.51.2