-static int screen, sx, sy, sw, sh;
-static int by, bh, blw, wx, wy, ww, wh;
+static int screen;
+static int sx, sy, sw, sh; /* X display screen geometry x, y, width, height */
+static int by, bh, blw; /* bar geometry y, height and layout symbol width */
+static int wx, wy, ww, wh; /* window area geometry x, y, width, height, bar excluded */