proc suckMotorProgram {{duration 10}} {

    #globals
    global scene
    global state
    global sack tail head spine

    # Start the clock at 0
    set u 0;

    set full    $sack(full);
    set headLen $head(length);
    set squish  $head(squish); 
    set squash  $head(squash);
    set tilt    $spine(tilt);

    # Clock stops at 1
    while {$u < 1} {

	##
	# Notice object: a chocolate chip cookie. Yum, yum...
	##

	if {$u < 1.0/60.0} {
	    set head(squish) [expr {lerpUp(($u * 60), $squish, 0.45)}];
	} {}

	if {$u > 1.0/60.0} {
	    if {$u < (4.0/60.0)} {
		set head(squish) [expr {lerpDown((($u - 1.0/60.0) * 20), 0.0, 0.45)}];
	    } {}
	} {}

	##
	# Eyes follow cookie the whole time
	##

	# ***

	##
	# Wag tail for a bit
	##

	# Wags faster if happier
	if {$u < 0.2} {
	    set tail(wig) [expr {sin (($u * 5) * ($state(happy) * 12) * pi())}];
	    set tail(wag) [expr {sin (($u * 5) * ($state(happy) *  8) * pi())}];
	} {
	    # Tail is straight by default
	    set tail(wig) 0.0; set tail(wag) 0.0;
	}

	##
	# Spine tilts back
	# Head stretches forward
	##

	# Tilts more if hungrier (sack is emptier)
	if {$u > 0.2} {
	    if {$u < 0.4} {
		set spine(tilt)  [expr {lerpDown((($u - 0.2) * 5), (1 - $full), 0.0)}];
		set head(length) [expr {lerpUp  ((($u - 0.2) * 5), $headLen,    6.0)}];
	    } {}
	} {}

	##
	# Suck
	# Drag the cookie in
	##

	# ***

	##
	# Spine returns to normal
	# Head stretches back
	##

	if {$u > 0.8} {
	    if {$u < 0.9} {
		set spine(tilt)  [expr {lerpUp  ((($u - 0.8) * 10), (1 - $full), $tilt)}];
		set head(length) [expr {lerpDown((($u - 0.8) * 10), 3.0,         6.0  )}];
		set head(squish) [expr {lerpUp  ((($u - 0.8) * 10), 0.0,         0.4  )}];
		set head(squash) [expr {lerpUp  ((($u - 0.8) * 10), $squash,     0.4  )}];
		if {$sack(full) < 1.0} {
		    set sack(full) [expr {$sack(full) + 0.1}];
		} {}
	    } {}
	} {}
	    
	##
	# Head returns to normal
	##

	if {$u > 0.9} {
	    set head(length) [expr {lerpUp  ((($u - 0.9) * 10), 3.0,     $headLen)}];
	    set head(squish) [expr {lerpDown((($u - 0.9) * 10), $squish, 0.4  )}];
	    set head(squash) [expr {lerpDown((($u - 0.9) * 10), $squash, 0.4  )}];
	} {}

	##
	# Yum, yum
	##	

	# Increment u and syncronize
	set u [expr {$u + (1.0/(($duration * $scene(ticksPerSecond)) - 1) * [synchWithScene])}]
    }

    set sack(full)   $full;
    set head(length) $headLen;
    set head(squish) $squish; 
    set head(squash) $squash;
    set spine(tilt)  $tilt;
}