patch: alpha

Allow dwm to have translucent bars, while keeping all the text on it
opaque, just like the alpha-patch for st.

Fix transparent borders
-----------------------
By default dwm might make windows' borders transparent when using
composit window manager (e.g. xcompmgr, picom). Alpha patch allows to
make borders opaque.

If all you want is to make borders opaque, you don't care about
statusbar opacity and/or have problems applying alpha patch, then you
might use fixborders patch instead.

5 files changed, 82 insertions, 22 deletions

diff --git a/config.def.h b/config.def.h
index ff2264e..4ac4099 100644
--- a/config.def.h
+++ b/config.def.h
@@ -12,11 +12,18 @@ static const char col_gray2[]       = "#222222";
 static const char col_gray3[]       = "#bbbbbb";
 static const char col_gray4[]       = "#eeeeee";
 static const char col_cyan[]        = "#002a3b";
+static const unsigned int baralpha = 0xd0;
+static const unsigned int borderalpha = OPAQUE;
 static const char *colors[][3]      = {
 	/*               fg         bg         border   */
 	[SchemeNorm] = { col_gray3, col_gray1, col_gray2 },
 	[SchemeSel]  = { col_gray4, col_cyan,  col_cyan  },
 };
+static const unsigned int alphas[][3]      = {
+	/*               fg      bg        border     */
+	[SchemeNorm] = { OPAQUE, baralpha, borderalpha },
+	[SchemeSel]  = { OPAQUE, baralpha, borderalpha },
+};
 
 /* tagging */
 static const char *tags[] = { "1", "2", "3", "4", "5", "6", "7", "8", "9", "0" };
diff --git a/config.mk b/config.mk
index ba64d3d..d609c42 100644
--- a/config.mk
+++ b/config.mk
@@ -23,7 +23,7 @@ FREETYPEINC = /usr/include/freetype2
 
 # includes and libs
 INCS = -I${X11INC} -I${FREETYPEINC}
-LIBS = -L${X11LIB} -lX11 ${XINERAMALIBS} ${FREETYPELIBS}
+LIBS = -L${X11LIB} -lX11 ${XINERAMALIBS} ${FREETYPELIBS} -lXrender
 
 # flags
 CPPFLAGS = -D_DEFAULT_SOURCE -D_BSD_SOURCE -D_XOPEN_SOURCE=700L -DVERSION=\"${VERSION}\" ${XINERAMAFLAGS}
diff --git a/drw.c b/drw.c
index a58a2b4..42700e5 100644
--- a/drw.c
+++ b/drw.c
@@ -61,7 +61,7 @@ utf8decode(const char *c, long *u, size_t clen)
 }
 
 Drw *
-drw_create(Display *dpy, int screen, Window root, unsigned int w, unsigned int h)
+drw_create(Display *dpy, int screen, Window root, unsigned int w, unsigned int h, Visual *visual, unsigned int depth, Colormap cmap)
 {
 	Drw *drw = ecalloc(1, sizeof(Drw));
 
@@ -70,8 +70,11 @@ drw_create(Display *dpy, int screen, Window root, unsigned int w, unsigned int h
 	drw->root = root;
 	drw->w = w;
 	drw->h = h;
-	drw->drawable = XCreatePixmap(dpy, root, w, h, DefaultDepth(dpy, screen));
-	drw->gc = XCreateGC(dpy, root, 0, NULL);
+	drw->visual = visual;
+	drw->depth = depth;
+	drw->cmap = cmap;
+	drw->drawable = XCreatePixmap(dpy, root, w, h, depth);
+	drw->gc = XCreateGC(dpy, drw->drawable, 0, NULL);
 	XSetLineAttributes(dpy, drw->gc, 1, LineSolid, CapButt, JoinMiter);
 
 	return drw;
@@ -87,7 +90,7 @@ drw_resize(Drw *drw, unsigned int w, unsigned int h)
 	drw->h = h;
 	if (drw->drawable)
 		XFreePixmap(drw->dpy, drw->drawable);
-	drw->drawable = XCreatePixmap(drw->dpy, drw->root, w, h, DefaultDepth(drw->dpy, drw->screen));
+	drw->drawable = XCreatePixmap(drw->dpy, drw->root, w, h, drw->depth);
 }
 
 void
@@ -181,21 +184,22 @@ drw_fontset_free(Fnt *font)
 }
 
 void
-drw_clr_create(Drw *drw, Clr *dest, const char *clrname)
+drw_clr_create(Drw *drw, Clr *dest, const char *clrname, unsigned int alpha)
 {
 	if (!drw || !dest || !clrname)
 		return;
 
-	if (!XftColorAllocName(drw->dpy, DefaultVisual(drw->dpy, drw->screen),
-	                       DefaultColormap(drw->dpy, drw->screen),
+	if (!XftColorAllocName(drw->dpy, drw->visual, drw->cmap,
 	                       clrname, dest))
 		die("error, cannot allocate color '%s'", clrname);
+
+	dest->pixel = (dest->pixel & 0x00ffffffU) | (alpha << 24);
 }
 
 /* Wrapper to create color schemes. The caller has to call free(3) on the
  * returned color scheme when done using it. */
 Clr *
-drw_scm_create(Drw *drw, const char *clrnames[], size_t clrcount)
+drw_scm_create(Drw *drw, const char *clrnames[], const unsigned int alphas[], size_t clrcount)
 {
 	size_t i;
 	Clr *ret;
@@ -205,7 +209,7 @@ drw_scm_create(Drw *drw, const char *clrnames[], size_t clrcount)
 		return NULL;
 
 	for (i = 0; i < clrcount; i++)
-		drw_clr_create(drw, &ret[i], clrnames[i]);
+		drw_clr_create(drw, &ret[i], clrnames[i], alphas[i]);
 	return ret;
 }
 
@@ -263,9 +267,7 @@ drw_text(Drw *drw, int x, int y, unsigned int w, unsigned int h, unsigned int lp
 	} else {
 		XSetForeground(drw->dpy, drw->gc, drw->scheme[invert ? ColFg : ColBg].pixel);
 		XFillRectangle(drw->dpy, drw->drawable, drw->gc, x, y, w, h);
-		d = XftDrawCreate(drw->dpy, drw->drawable,
-		                  DefaultVisual(drw->dpy, drw->screen),
-		                  DefaultColormap(drw->dpy, drw->screen));
+		d = XftDrawCreate(drw->dpy, drw->drawable, drw->visual, drw->cmap);
 		x += lpad;
 		w -= lpad;
 	}
diff --git a/drw.h b/drw.h
index 6471431..94b8bbd 100644
--- a/drw.h
+++ b/drw.h
@@ -20,6 +20,9 @@ typedef struct {
 	Display *dpy;
 	int screen;
 	Window root;
+	Visual *visual;
+	unsigned int depth;
+	Colormap cmap;
 	Drawable drawable;
 	GC gc;
 	Clr *scheme;
@@ -27,7 +30,7 @@ typedef struct {
 } Drw;
 
 /* Drawable abstraction */
-Drw *drw_create(Display *dpy, int screen, Window win, unsigned int w, unsigned int h);
+Drw *drw_create(Display *dpy, int screen, Window win, unsigned int w, unsigned int h, Visual *visual, unsigned int depth, Colormap cmap);
 void drw_resize(Drw *drw, unsigned int w, unsigned int h);
 void drw_free(Drw *drw);
 
@@ -39,8 +42,8 @@ unsigned int drw_fontset_getwidth_clamp(Drw *drw, const char *text, unsigned int
 void drw_font_getexts(Fnt *font, const char *text, unsigned int len, unsigned int *w, unsigned int *h);
 
 /* Colorscheme abstraction */
-void drw_clr_create(Drw *drw, Clr *dest, const char *clrname);
-Clr *drw_scm_create(Drw *drw, const char *clrnames[], size_t clrcount);
+void drw_clr_create(Drw *drw, Clr *dest, const char *clrname, unsigned int alpha);
+Clr *drw_scm_create(Drw *drw, const char *clrnames[], const unsigned int alphas[], size_t clrcount);
 
 /* Cursor abstraction */
 Cur *drw_cur_create(Drw *drw, int shape);
diff --git a/dwm.c b/dwm.c
index f1d86b2..7ca234b 100644
--- a/dwm.c
+++ b/dwm.c
@@ -57,6 +57,8 @@
 #define TAGMASK                 ((1 << LENGTH(tags)) - 1)
 #define TEXTW(X)                (drw_fontset_getwidth(drw, (X)) + lrpad)
 
+#define OPAQUE                  0xffU
+
 /* enums */
 enum { CurNormal, CurResize, CurMove, CurLast }; /* cursor */
 enum { SchemeNorm, SchemeSel }; /* color schemes */
@@ -232,6 +234,7 @@ static Monitor *wintomon(Window w);
 static int xerror(Display *dpy, XErrorEvent *ee);
 static int xerrordummy(Display *dpy, XErrorEvent *ee);
 static int xerrorstart(Display *dpy, XErrorEvent *ee);
+static void xinitvisual();
 static void zoom(const Arg *arg);
 
 /* variables */
@@ -268,6 +271,11 @@ static Drw *drw;
 static Monitor *mons, *selmon;
 static Window root, wmcheckwin;
 
+static int useargb = 0;
+static Visual *visual;
+static int depth;
+static Colormap cmap;
+
 /* configuration, allows nested code to access above variables */
 #include "config.h"
 
@@ -1558,7 +1566,8 @@ setup(void)
 	sw = DisplayWidth(dpy, screen);
 	sh = DisplayHeight(dpy, screen);
 	root = RootWindow(dpy, screen);
-	drw = drw_create(dpy, screen, root, sw, sh);
+	xinitvisual();
+	drw = drw_create(dpy, screen, root, sw, sh, visual, depth, cmap);
 	if (!drw_fontset_create(drw, fonts, LENGTH(fonts)))
 		die("no fonts could be loaded.");
 	lrpad = drw->fonts->h;
@@ -1586,7 +1595,7 @@ setup(void)
 	/* init appearance */
 	scheme = ecalloc(LENGTH(colors), sizeof(Clr *));
 	for (i = 0; i < LENGTH(colors); i++)
-		scheme[i] = drw_scm_create(drw, colors[i], 3);
+		scheme[i] = drw_scm_create(drw, colors[i], alphas[i], 3);
 	/* init bars */
 	updatebars();
 	updatestatus();
@@ -1821,16 +1830,18 @@ updatebars(void)
 	Monitor *m;
 	XSetWindowAttributes wa = {
 		.override_redirect = True,
-		.background_pixmap = ParentRelative,
+		.background_pixel = 0,
+		.border_pixel = 0,
+		.colormap = cmap,
 		.event_mask = ButtonPressMask|ExposureMask
 	};
 	XClassHint ch = {"dwm", "dwm"};
 	for (m = mons; m; m = m->next) {
 		if (m->barwin)
 			continue;
-		m->barwin = XCreateWindow(dpy, root, m->wx, m->by, m->ww, bh, 0, DefaultDepth(dpy, screen),
-				CopyFromParent, DefaultVisual(dpy, screen),
-				CWOverrideRedirect|CWBackPixmap|CWEventMask, &wa);
+		m->barwin = XCreateWindow(dpy, root, m->wx, m->by, m->ww, bh, 0, depth,
+		                          InputOutput, visual,
+		                          CWOverrideRedirect|CWBackPixel|CWBorderPixel|CWColormap|CWEventMask, &wa);
 		XDefineCursor(dpy, m->barwin, cursor[CurNormal]->cursor);
 		XMapRaised(dpy, m->barwin);
 		XSetClassHint(dpy, m->barwin, &ch);
@@ -2129,6 +2140,43 @@ xerrorstart(Display *dpy, XErrorEvent *ee)
 }
 
 void
+xinitvisual()
+{
+	XVisualInfo *infos;
+	XRenderPictFormat *fmt;
+	int nitems;
+	int i;
+
+	XVisualInfo tpl = {
+		.screen = screen,
+		.depth = 32,
+		.class = TrueColor
+	};
+	long masks = VisualScreenMask | VisualDepthMask | VisualClassMask;
+
+	infos = XGetVisualInfo(dpy, masks, &tpl, &nitems);
+	visual = NULL;
+	for(i = 0; i < nitems; i ++) {
+		fmt = XRenderFindVisualFormat(dpy, infos[i].visual);
+		if (fmt->type == PictTypeDirect && fmt->direct.alphaMask) {
+			visual = infos[i].visual;
+			depth = infos[i].depth;
+			cmap = XCreateColormap(dpy, root, visual, AllocNone);
+			useargb = 1;
+			break;
+		}
+	}
+
+	XFree(infos);
+
+	if (! visual) {
+		visual = DefaultVisual(dpy, screen);
+		depth = DefaultDepth(dpy, screen);
+		cmap = DefaultColormap(dpy, screen);
+	}
+}
+
+void
 zoom(const Arg *arg)
 {
 	Client *c = selmon->sel;