# -*- tcl -*- tcl.tk//DSL diagram//EN//1.0
# Plot a single jumper in a box, atr is the on-off state.
proc jumper {bool} {block {
    set shrinkfactor 0.8
    set Outer [box]

    # Count on end of block to reset these
    set boxwidth  [expr {[$Outer width]  * ($shrinkfactor / 2.)}]
    set boxheight [expr {[$Outer height] * ($shrinkfactor / 2.)}]

    if {$bool} {
	set oncolor  black
	set offcolor white
    } else {
	set oncolor  white
	set offcolor black
    }

    box fillcolor $offcolor with s at $Outer
    box fillcolor $oncolor  with n at $Outer
}}

# Plot a block of six jumpers.
proc jumperblock {a b c d e f} {block {
    jumper $a
    jumper $b
    jumper $c
    jumper $d
    jumper $e
    jumper $f

    set jwidth  [[last block] Outer width]
    set jheight [[last block] Outer height]

    box with nw at [6th last block nw] width [expr {6*$jwidth}] height $jheight
    group {
	down ; move
	text "Jumpers in state $a$b$c$d$e$f"
    }
}}

# Sample macro invocations.
jumperblock 1 1 0 0 1 0
move
jumperblock 1 0 1 0 1 1