diff -r 440dda47ae5b config.def.h
--- a/config.def.h	Fri May 29 09:29:22 2009 +0100
+++ b/config.def.h	Thu Jun 04 13:29:18 2009 +0100
@@ -78,6 +78,10 @@
 	TAGKEYS(                        XK_8,                      7)
 	TAGKEYS(                        XK_9,                      8)
 	{ MODKEY|ShiftMask,             XK_q,      quit,           {0} },
+#ifdef XCOMPOSITE
+	{ MODKEY,			XK_e,	   xcompexpose,	   { .ui = ~0 } },
+	{ MODKEY|ShiftMask,		XK_e,	   xcompexpose,	   { .ui = 0 } },
+#endif
 };
 
 /* button definitions */
diff -r 440dda47ae5b config.mk
--- a/config.mk	Fri May 29 09:29:22 2009 +0100
+++ b/config.mk	Thu Jun 04 13:29:18 2009 +0100
@@ -14,12 +14,16 @@
 XINERAMALIBS = -L${X11LIB} -lXinerama
 XINERAMAFLAGS = -DXINERAMA
 
+# XComposite
+XCOMPOSITELIBS = -L${X11LIB} -lXcomposite -lXrender -lm
+XCOMPOSITEFLAGS = -DXCOMPOSITE
+
 # includes and libs
 INCS = -I. -I/usr/include -I${X11INC}
-LIBS = -L/usr/lib -lc -L${X11LIB} -lX11 ${XINERAMALIBS}
+LIBS = -L/usr/lib -lc -L${X11LIB} -lX11 ${XINERAMALIBS} ${XCOMPOSITELIBS}
 
 # flags
-CPPFLAGS = -DVERSION=\"${VERSION}\" ${XINERAMAFLAGS}
+CPPFLAGS = -DVERSION=\"${VERSION}\" ${XINERAMAFLAGS} ${XCOMPOSITEFLAGS}
 CFLAGS = -std=c99 -pedantic -Wall -Os ${INCS} ${CPPFLAGS}
 LDFLAGS = -s ${LIBS}
 
diff -r 440dda47ae5b dwm.c
--- a/dwm.c	Fri May 29 09:29:22 2009 +0100
+++ b/dwm.c	Thu Jun 04 13:29:18 2009 +0100
@@ -39,6 +39,11 @@
 #ifdef XINERAMA
 #include <X11/extensions/Xinerama.h>
 #endif
+#ifdef XCOMPOSITE
+#include <math.h>
+#include <X11/extensions/Xcomposite.h>
+#include <X11/extensions/Xrender.h>
+#endif
 
 /* macros */
 #define BUTTONMASK              (ButtonPressMask|ButtonReleaseMask)
@@ -89,6 +94,12 @@
 	Client *next;
 	Client *snext;
 	Window win;
+#ifdef XCOMPOSITE
+	struct {
+		Picture pic;
+		int x, y, w, h;
+	} composite;
+#endif
 };
 
 typedef struct {
@@ -203,6 +214,17 @@
 static int xerrorstart(Display *dpy, XErrorEvent *ee);
 static void zoom(const Arg *arg);
 
+#ifdef XCOMPOSITE
+static void xcompexpose(const Arg *arg);
+static struct {
+	Picture overlayPic;
+	Window overlayWin;
+	unsigned int tagmask;
+	void (*button)(XEvent*);
+	void (*key)(XEvent*);
+} xcomp;
+#endif
+
 /* variables */
 static char stext[256];
 static int screen;
@@ -964,6 +986,9 @@
 	attach(c);
 	attachstack(c);
 	XMoveResizeWindow(dpy, c->win, c->x + 2 * sw, c->y, c->w, c->h); /* some windows require this */
+#ifdef XCOMPOSITE
+	XCompositeRedirectWindow(dpy, c->win, CompositeRedirectAutomatic);
+#endif
 	XMapWindow(dpy, c->win);
 	setclientstate(c, NormalState);
 	arrange();
@@ -1182,6 +1207,186 @@
 	while(XCheckMaskEvent(dpy, EnterWindowMask, &ev));
 }
 
+#ifdef XCOMPOSITE
+Picture
+xcomppicfromwin(Window win) {
+	XWindowAttributes attr;
+	XRenderPictFormat* fmt;
+	XRenderPictureAttributes pa;
+	Picture pict;
+
+	XGetWindowAttributes(dpy, win, &attr);
+	fmt = XRenderFindVisualFormat(dpy, attr.visual);
+	pa.subwindow_mode = IncludeInferiors;
+	pict = XRenderCreatePicture(dpy, win, fmt, CPSubwindowMode, &pa);
+
+	return pict;
+}
+
+void
+xcompscaleclient(Client* c, double sf) {
+	XTransform xform = {{
+		{ XDoubleToFixed(1/sf), XDoubleToFixed(0), XDoubleToFixed(0) },
+		{ XDoubleToFixed(0), XDoubleToFixed(1/sf), XDoubleToFixed(0) },
+		{ XDoubleToFixed(0), XDoubleToFixed(0), XDoubleToFixed(1) }
+	}};
+	XRenderSetPictureTransform(dpy, c->composite.pic, &xform);
+	XRenderSetPictureFilter(dpy, c->composite.pic, FilterBilinear, 0, 0);
+	c->composite.w = ((double)c->w * sf);
+	c->composite.h = ((double)c->h * sf);
+}
+
+void xcompfitclient(Client* c, int w, int h) {
+	double sfx = (double)w / (double)c->w;
+	double sfy = (double)h / (double)c->h;
+	xcompscaleclient(c, sfx > sfy ? sfy : sfx);
+}
+
+void
+xcompcleanup(void) {
+	XRenderFreePicture(dpy, xcomp.overlayPic);
+	XCompositeReleaseOverlayWindow(dpy, xcomp.overlayWin);
+	XUngrabPointer(dpy, CurrentTime);
+	handler[ButtonPress] = xcomp.button;
+	handler[KeyPress] = xcomp.key;
+}
+
+void
+xcompbuttonpress(XEvent* ev) {
+	XButtonEvent* bev = &ev->xbutton;
+	Client* c;
+
+	for(c = clients; c != NULL; c = c->next) {
+		if((c->tags & xcomp.tagmask) == 0) {
+			continue;
+		}
+		if(INRECT(bev->x, bev->y, c->composite.x, c->composite.y, c->composite.w, c->composite.h)) {
+			{
+				Arg arg;
+				arg.ui = c->tags;
+				view(&arg);
+			}
+			/* From zoom */
+			detach(c);
+			attach(c);
+			focus(c);
+			arrange();
+
+			xcompcleanup();
+			/* From swarp */
+			XWarpPointer(dpy, None, c->win, 0, 0, 0, 0, c->w / 2, c->h / 2);
+			XSetInputFocus(dpy, PointerRoot, RevertToPointerRoot, CurrentTime);
+		}
+	}
+}
+
+void
+xcompkeypress(XEvent* ev) {
+	/* Would be nice to have keyboard control */
+	xcompcleanup();
+}
+
+Bool
+xcomparrangeclients(void) {
+	int nsqx, nsqy;
+	int sqw, sqh;
+	unsigned int n;
+	Client* c;
+
+	for(c = clients, n = 0; c != NULL; c = c->next) {
+		if((c->tags & xcomp.tagmask) == 0) {
+			continue;
+		}
+		if(c->composite.pic != None) {
+			XRenderFreePicture(dpy, c->composite.pic);
+		}
+		c->composite.pic = xcomppicfromwin(c->win);
+		c->composite.x = 0;
+		c->composite.y = 0;
+		c->composite.w = c->w;
+		c->composite.h = c->h;
+		n++;
+	}
+
+	if(n <= 1) {
+		return True;
+	}
+
+	nsqy = nsqx = ceil(sqrt((double)n));
+	if(n <= nsqx * (nsqy - 1)) {
+		nsqy -= 1;
+	}
+
+	sqw = sw / nsqx;
+	sqh = sh / nsqy;
+
+	for(n = 0, c = clients; c != NULL; c = c->next) {
+		if((c->tags & xcomp.tagmask) == 0) {
+			continue;
+		}
+		xcompfitclient(c, sqw - 10, sqh - 10);
+		c->composite.x = (sqw * (n % nsqx));
+		c->composite.y = (sqh * (n / nsqx));
+
+		c->composite.x += (sqw - c->composite.w) / 2;
+		c->composite.y += (sqh - c->composite.h) / 2;
+
+		XRenderComposite(dpy, PictOpOver,
+			c->composite.pic, None, xcomp.overlayPic,
+			0, 0, 0, 0,
+			c->composite.x, c->composite.y,
+			c->composite.w, c->composite.h
+		);
+		n++;
+	}
+	return False;
+}
+
+void
+xcompexpose(const Arg *arg) {
+	XRenderColor col = { .red = 0, .green = 0, .blue = 0, .alpha = 0x4000 };
+
+	if(arg->ui & TAGMASK) {
+		xcomp.tagmask = arg->ui;
+	} else {
+		xcomp.tagmask = tagset[seltags];
+	}
+
+	if(clients == NULL) {
+		return;
+	}
+	xcomp.overlayWin = XCompositeGetOverlayWindow(dpy, root);
+	if(xcomp.overlayWin == None) {
+		fprintf(stderr, "dwm: composite: Could not get overlay window\n");
+		return;
+	}
+	xcomp.overlayPic = xcomppicfromwin(xcomp.overlayWin);
+
+	XRenderFillRectangle(dpy, PictOpOver, xcomp.overlayPic, &col, 0, 0, sw, sh);
+
+	if(xcomparrangeclients()) {
+		XRenderFreePicture(dpy, xcomp.overlayPic);
+		XCompositeReleaseOverlayWindow(dpy, xcomp.overlayWin);
+		return;
+	}
+
+	if(XGrabPointer(dpy, xcomp.overlayWin, True, ButtonPressMask, GrabModeAsync, GrabModeAsync, xcomp.overlayWin, None, CurrentTime) != GrabSuccess) {
+		fprintf(stderr, "dwm: composite: Could not grab pointer\n");
+		xcompcleanup();
+		return;
+	}
+	if(XGrabKeyboard(dpy, xcomp.overlayWin, True, GrabModeAsync, GrabModeAsync, CurrentTime) != GrabSuccess) {
+		fprintf(stderr, "dwm: composite: Could not grab keyboard\n");
+		xcompcleanup();
+		return;
+	}
+	xcomp.button = handler[ButtonPress];
+	xcomp.key = handler[KeyPress];
+	handler[ButtonPress] = &xcompbuttonpress;
+	handler[KeyPress] = &xcompkeypress;
+}
+#endif
+
 void
 run(void) {
 	XEvent ev;
@@ -1273,6 +1478,30 @@
 	lt[1] = &layouts[1 % LENGTH(layouts)];
 	updategeom();
 
+#ifdef XCOMPOSITE
+	{
+		int event_base, error_base, major = 0, minor = 2;
+		if(!XRenderQueryExtension(dpy, &event_base, &error_base)) {
+			die("Server does not support XRender");
+		}
+		major = 0;
+		minor = 10;
+		XRenderQueryVersion(dpy, &major, &minor);
+		if(minor < 10) {
+			die("Server XRender version %i.%i incompatible", major, minor);
+		}
+		if(!XCompositeQueryExtension(dpy, &event_base, &error_base)) {
+			die("Server does not support XComposite");
+		}
+		major = 0;
+		minor = 2;
+		XCompositeQueryVersion(dpy, &major, &minor);
+		if(minor < 2) {
+			die("Server XComposite version %i.%i incompatible", major, minor);
+		}
+		XCompositeRedirectSubwindows(dpy, screen, CompositeRedirectAutomatic);
+	}
+#endif
 	/* init atoms */
 	wmatom[WMProtocols] = XInternAtom(dpy, "WM_PROTOCOLS", False);
 	wmatom[WMDelete] = XInternAtom(dpy, "WM_DELETE_WINDOW", False);