From 9982f3cf8ddf30104b0e73f817ce8c820049af5a Mon Sep 17 00:00:00 2001
From: Matt Hunter <m@lfurio.us>
Date: Sat, 17 Jan 2026 19:45:32 -0500
Subject: patch: alpha

This patch allows users to change the opacity of the background.  Note
that you need an X composite manager (e.g. compton, xcompmgr) to make
this patch effective.

The alpha value affects the default background only.  The color
designated by 'defaultbg' should not be used elsewhere.  Embedding might
fail after applying this patch.
---
 x.c | 44 +++++++++++++++++++++++++++++++++++---------
 1 file changed, 35 insertions(+), 9 deletions(-)

(limited to 'x.c')

diff --git a/x.c b/x.c
index d73152b..f32fd6c 100644
--- a/x.c
+++ b/x.c
@@ -105,6 +105,7 @@ 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;
@@ -752,7 +753,7 @@ 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 +813,10 @@ xloadcols(void)
 			else
 				die("could not allocate color %d\n", i);
 		}
+
+	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;
 }
 
@@ -842,6 +847,12 @@ xsetcolorname(int x, const char *name)
 	XftColorFree(xw.dpy, xw.vis, xw.cmap, &dc.col[x]);
 	dc.col[x] = ncolor;
 
+	if (x == defaultbg) {
+		dc.col[defaultbg].color.alpha = (unsigned short)(0xffff * alpha);
+		dc.col[defaultbg].pixel &= 0x00FFFFFF;
+		dc.col[defaultbg].pixel |= (unsigned char)(0xff * alpha) << 24;
+	}
+
 	return 0;
 }
 
@@ -1134,11 +1145,25 @@ xinit(int cols, int rows)
 	Window parent, root;
 	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);
+
+	root = XRootWindow(xw.dpy, xw.scr);
+	if (!(opt_embed && (parent = strtol(opt_embed, NULL, 0))))
+		parent = root;
+
+	if (XMatchVisualInfo(xw.dpy, xw.scr, 32, TrueColor, &vis) != 0) {
+		xw.vis = vis.visual;
+		xw.depth = vis.depth;
+	} else {
+		XGetWindowAttributes(xw.dpy, parent, &attr);
+		xw.vis = attr.visual;
+		xw.depth = attr.depth;
+	}
 
 	/* font */
 	if (!FcInit())
@@ -1148,7 +1173,7 @@ xinit(int cols, int rows)
 	xloadfonts(usedfont, 0);
 
 	/* colors */
-	xw.cmap = XDefaultColormap(xw.dpy, xw.scr);
+	xw.cmap = XCreateColormap(xw.dpy, parent, xw.vis, None);
 	xloadcols();
 
 	/* adjust fixed window geometry */
@@ -1168,11 +1193,8 @@ xinit(int cols, int rows)
 		| ButtonMotionMask | ButtonPressMask | ButtonReleaseMask;
 	xw.attrs.colormap = xw.cmap;
 
-	root = XRootWindow(xw.dpy, xw.scr);
-	if (!(opt_embed && (parent = strtol(opt_embed, NULL, 0))))
-		parent = root;
-	xw.win = XCreateWindow(xw.dpy, root, xw.l, xw.t,
-			win.w, win.h, 0, XDefaultDepth(xw.dpy, xw.scr), InputOutput,
+	xw.win = XCreateWindow(xw.dpy, parent, xw.l, xw.t,
+			win.w, win.h, 0, xw.depth, InputOutput,
 			xw.vis, CWBackPixel | CWBorderPixel | CWBitGravity
 			| CWEventMask | CWColormap, &xw.attrs);
 	if (parent != root)
@@ -1183,7 +1205,7 @@ xinit(int cols, int rows)
 	dc.gc = XCreateGC(xw.dpy, xw.win, GCGraphicsExposures,
 			&gcvalues);
 	xw.buf = XCreatePixmap(xw.dpy, xw.win, win.w, win.h,
-			DefaultDepth(xw.dpy, xw.scr));
+			xw.depth);
 	XSetForeground(xw.dpy, dc.gc, dc.col[defaultbg].pixel);
 	XFillRectangle(xw.dpy, xw.buf, dc.gc, 0, 0, win.w, win.h);
 
@@ -2047,6 +2069,10 @@ main(int argc, char *argv[])
 	case 'a':
 		allowaltscreen = 0;
 		break;
+	case 'A':
+		alpha = strtof(EARGF(usage()), NULL);
+		LIMIT(alpha, 0.0, 1.0);
+		break;
 	case 'c':
 		opt_class = EARGF(usage());
 		break;
-- 
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