#!/bin/csh -f
#+
# focusloop -- acquire images over a range of internal focus positions
#
# Purpose:
#	Given a starting internal focus value, acquire a series of
#	images while changing the internal focus value. 
#
# Usage:
#	focusloop [start [<n> [incr]]]
# 
# Arguments:
#	start = starting secondary position [microns] (default=-3250)
#	n     = number of images to acquire (default=7, max=100)
#	incr  = increment in focus [microns] (default=-1000)
# 
# Output:
# 
# Restrictions:
# 
# Exit values:
#	0 = normal completion
#	1 = wrong number of arguments
#	3 = start and/or incr are not valid floats
#	4 = n too large
#
# Example:
#	1) Acquire a series of 7 focus frames starting at -3250 
#	at -1000 micron increments
#		focusloop
# 
# 	2) Acquire a series of 11 focus frames starting at -7000
#	at 100 micron increments
#		focusloop -7000 11 100
#-
# Modification history:
#	Date unknown	RWG	Original version
#	2000-Jul-11	GDW	Added documentation
#	2000-Oct-09	GDW	Updated documentation
#	2002-Jun-06	GDW	Adapted for DEIMOS
#	2002-Aug-14	GDW	Removed backlash compensation 
#				(already in DEIMOS motor control software)
#-----------------------------------------------------------------------

# extract command name...
set buf = $0
set cmd = $buf:t

# define defaults...
set usage = "Usage: $cmd [start [n [incr]]]"
set incr = -1000
@ start = -3250
@ n = 7
@ n_max = 100

# verify args...
if ( $#argv > 3 ) then
  echo "$usage"
  exit 1
endif

# grab arguments...
if ( $#argv >= 1) then
    set start = $1
    shift
endif
if ( $#argv >= 1 ) then
    set n = $1
    shift
endif
if ( $#argv >= 1 ) then
    set incr = $1
    shift
endif

# validate args...
is_float $start $incr > /dev/null
if ( $status ) then
  echo "ERROR -- start and/or incr are not valid floats"
  exit 3
endif

if ( $n > $n_max ) then
  echo "ERROR --- n too large (max is $n_max)"
  exit 4
endif

# trap CTRL-C...
onintr quit
set old_focus = `focus`

# acquire data...
@ i = 0
while ( $i < $n )

    # compute new secondary position...
    set focus = `calc "$start + $i*$incr"`

    # change focus position...
    focus $focus

    # report new position...
    @ j=$i
    @ j++
    printf "-----------------------------------------------------------------------\n"
    printf "Acquiring image %d of %d (%s) at %.0f\n" \
	$j $n `nextimage -tail` `focus`
    printf "-----------------------------------------------------------------------\n"

    # acquire image(s) using the appropriate command...
    goi

    # increment...
    @ i++
end

# reset focus value...
quit:
focus $old_focus