2 files changed, 120 insertions, 0 deletions
diff --git a/mkfile b/mkfile
new file mode 100644
index 0000000..41a3031
--- /dev/null
+++ b/mkfile
@@ -0,0 +1,8 @@
+</$objtype/mkfile
+
+BIN=/$objtype/bin
+TARG=volume
+OFILES=\
+	volume.$O
+
+</sys/src/cmd/mkone
diff --git a/volume.c b/volume.c
new file mode 100644
index 0000000..c1d394a
--- /dev/null
+++ b/volume.c
@@ -0,0 +1,112 @@
+#include <u.h>
+#include <libc.h>
+#include <draw.h>
+#include <event.h>
+
+enum {
+	SEC = 1000
+};
+
+int vfd, volume;
+int ismixfs;
+Image *knob;
+Image *back;
+Image *rim;
+
+Point
+volumept(Point c, int volume, int r)
+{
+	double rad;
+
+	rad = (double)(volume*3.0+30) * PI/180.0;
+	c.x -= sin(rad) * r;
+	c.y += cos(rad) * r;
+	return c;
+}
+
+void
+redraw(void)
+{
+	Point c;
+
+	c = divpt(addpt(screen->r.min, screen->r.max), 2);
+	draw(screen, screen->r, back, nil, ZP);
+	line(screen, volumept(c, 0, 45), volumept(c, 0, 40), 0, 0, 1, display->black, ZP);
+	line(screen, volumept(c, 100, 45), volumept(c, 100, 40), 0, 0, 1, display->black, ZP);
+	ellipse(screen, c, 40, 40, 1, rim, ZP);
+	fillellipse(screen, volumept(c, volume, 30), 3, 3, knob, ZP);
+}
+
+void
+update(void)
+{
+	char buf[256], *s;
+	int n;
+
+	if((n = pread(vfd, buf, sizeof(buf)-1, 0)) <= 0)
+		sysfatal("pread: %r");
+	buf[n] = 0;
+	strtok(buf, " ");
+	s = strtok(nil, " ");
+	volume = strtol(s, nil, 0);
+}
+
+void
+eresized(int new)
+{
+	if(new && getwindow(display, Refnone) < 0)
+		fprint(2, "can't reattach to window");
+	redraw();
+}
+
+void
+main()
+{
+	Mouse m;
+	Event e;
+	Point p;
+	double rad;
+	int Etimer, key, d;
+	char buf[3];
+
+	vfd = open("/dev/volume", ORDWR);
+	if(vfd < 0)
+		sysfatal("open: %r");
+	read(vfd, buf, sizeof buf);
+	ismixfs = strncmp(buf, "mix", 3) == 0;
+	update();
+	if(initdraw(0, 0, "volume") < 0)
+		sysfatal("initdraw: %r");
+	back = allocimagemix(display, 0x88FF88FF, DWhite);
+	knob = allocimage(display, Rect(0,0,1,1), CMAP8, 1, 0x008800FF);
+	rim = allocimage(display, Rect(0,0,1,1), CMAP8, 1, 0x004400FF);
+	einit(Emouse);
+	Etimer = etimer(0, 2*SEC);
+	redraw();
+	for(;;){
+		key = event(&e);
+		if(key == Emouse){
+			m = e.mouse;
+			if(m.buttons & 1){
+				p = subpt(m.xy, divpt(addpt(screen->r.min, screen->r.max), 2));
+				rad = atan2(-p.x, p.y);
+				d = rad * 180.0/PI;
+				if(d < 0)
+					d += 360;
+				d *= 160.0/360.0;
+				if(d < 30)
+					d = 0;
+				else if(d > 130)
+					d = 100;
+				else
+					d -= 30;
+				volume = d;
+				fprint(vfd, "%s%d", ismixfs? "mix " : "", volume);
+				redraw();
+			}
+		}else if(key == Etimer){
+			update();
+			redraw();
+		}
+	}
+}