options: remove --respect-prop-shadow

A quick search on GitHub showing the _COMPTON_SHADOW is actively being
used (most noteably, by polybar). It is not a difficult thing to support,
and it doesn't have that much runtime overhead. So remove the option
that guards this feature, make it enabled by default.

(Side note, I saw lots of people putting this option in their config
files, but this is actually a command line only option.)

Signed-off-by: Yuxuan Shui <yshuiv7@gmail.com>

man/compton.1.asciidoc

@@ -139,9 +139,6 @@ OPTIONS
 *--use-ewmh-active-win*::
 	Use EWMH '_NET_ACTIVE_WINDOW' to determine currently focused window, rather than listening to 'FocusIn'/'FocusOut' event. Might have more accuracy, provided that the WM supports it.
 
-*--respect-prop-shadow*::
-	Respect '_COMPTON_SHADOW'. This a prototype-level feature, which you must not rely on.
-
 *--unredir-if-possible*::
 	Unredirect all windows if a full-screen opaque window is detected, to maximize performance for full-screen windows. Known to cause flickering when redirecting/unredirecting windows. *--paint-on-overlay* may make the flickering less obvious.
 

src/config.c

@@ -524,7 +524,6 @@ char *parse_config(options_t *opt, const char *config_file, bool *shadow_enable,
 	    .shadow_opacity = .75,
 	    .shadow_blacklist = NULL,
 	    .shadow_ignore_shaped = false,
-	    .respect_prop_shadow = false,
 	    .xinerama_shadow_crop = false,
 
 	    .fade_in_step = 0.028,

src/config.h

@@ -149,8 +149,6 @@ typedef struct options {
 	c2_lptr_t *shadow_blacklist;
 	/// Whether bounding-shaped window should be ignored.
 	bool shadow_ignore_shaped;
-	/// Whether to respect _COMPTON_SHADOW.
-	bool respect_prop_shadow;
 	/// Whether to crop shadow to the very Xinerama screen.
 	bool xinerama_shadow_crop;
 

src/event.c

@@ -516,7 +516,7 @@ static inline void ev_property_notify(session_t *ps, xcb_property_notify_event_t
 	}
 
 	// If _COMPTON_SHADOW changes
-	if (ps->o.respect_prop_shadow && ps->atoms->a_COMPTON_SHADOW == ev->atom) {
+	if (ps->atoms->a_COMPTON_SHADOW == ev->atom) {
 		auto w = find_managed_win(ps, ev->window);
 		if (w) {
 			win_update_prop_shadow(ps, w);

src/options.c

@@ -168,10 +168,6 @@ static void usage(int ret) {
 	    "  Use _NET_WM_ACTIVE_WINDOW on the root window to determine which\n"
 	    "  window is focused instead of using FocusIn/Out events.\n"
 	    "\n"
-	    "--respect-prop-shadow\n"
-	    "  Respect _COMPTON_SHADOW. This a prototype-level feature, which\n"
-	    "  you must not rely on.\n"
-	    "\n"
 	    "--unredir-if-possible\n"
 	    "  Unredirect all windows if a full-screen opaque window is\n"
 	    "  detected, to maximize performance for full-screen windows.\n"
@@ -635,7 +631,12 @@ void get_cfg(options_t *opt, int argc, char *const *argv, bool shadow_enable,
 			         " from the command line options");
 			break;
 		P_CASEBOOL(276, use_ewmh_active_win);
-		P_CASEBOOL(277, respect_prop_shadow);
+		case 277:
+			// --respect-prop-shadow
+			log_warn("--respect-prop-shadow option has been deprecated, its "
+			         "functionality will always be enabled. Please remove it "
+			         "from the command line options");
+			break;
 		P_CASEBOOL(278, unredir_if_possible);
 		case 279:
 			// --focus-exclude

src/win.c

@@ -738,7 +738,7 @@ static void win_determine_shadow(session_t *ps, struct managed_win *w) {
 		           !w->rounded_corners) {
 			log_debug("Shadow disabled by shadow-ignore-shaped");
 			shadow_new = false;
-		} else if (ps->o.respect_prop_shadow && w->prop_shadow == 0) {
+		} else if (w->prop_shadow == 0) {
 			log_debug("Shadow disabled by shadow property");
 			shadow_new = false;
 		}
@@ -2080,9 +2080,7 @@ void map_win_start(session_t *ps, struct managed_win *w) {
 	win_update_opacity_prop(ps, w);
 
 	// Check for _COMPTON_SHADOW
-	if (ps->o.respect_prop_shadow) {
-		win_update_prop_shadow_raw(ps, w);
-	}
+	win_update_prop_shadow_raw(ps, w);
 
 	// Many things above could affect shadow
 	win_determine_shadow(ps, w);