#!/usr/bin/env perl

# Plot the laplacian field on the gray surfaces. This
# shows how good the convergence of the gray surfaces is.
#
# Copyright Alan C. Evans
# Professor of Neurology
# McGill University
#

use strict;
use warnings "all";
use File::Temp qw/ tempdir /;

my ($gm_left, $gm_right, $clasp_field, $output) = @ARGV;
unless($output) {
  print "Usage: $0 <gm_left.obj> <gm_right.obj> <clasp_field.mnc> <output.png>\n";
  print "Note that none of the inputs may be compressed!\n";
  exit(1);
}

my $tmpdir = tempdir( CLEANUP => 1 );
my $tilesize = 240;
my $debug = 0;
my $quiet = 1;
my @mont_args = ();
my @DrawText = ( "-font", "Helvetica" );

my $xpos = 1.2*$tilesize;
my $ypos = 15;

# Intersect gray surfaces with Laplacian field.
my $phi_left = "${tmpdir}/phi_left.txt";
`volume_object_evaluate -linear $clasp_field $gm_left $phi_left`;
my $phi_right = "${tmpdir}/phi_right.txt";
`volume_object_evaluate -linear $clasp_field $gm_right $phi_right`;

# Title: Write min/max of Laplacian field on gray surfaces
my @ret = `vertstats_stats $phi_left |grep Minimum`;
$ret[0] =~ / Minimum: (.*)/;
my $left_min = $1;
@ret = `vertstats_stats $phi_right |grep Minimum`;
$ret[0] =~ / Minimum: (.*)/;
my $right_min = $1;

@ret = `vertstats_stats $phi_left |grep Maximum`;
$ret[0] =~ / Maximum: (.*)/;
my $left_max = $1;
@ret = `vertstats_stats $phi_right |grep Maximum`;
$ret[0] =~ / Maximum: (.*)/;
my $right_max = $1;

my $phi_min = ( $left_min < $right_min ) ? $left_min : $right_min;
my $phi_max = ( $left_max > $right_max ) ? $left_max : $right_max;

my $title = sprintf( "Laplacian field on gray surfaces (Min=%f, Max=%f)", $phi_min, $phi_max );
push @DrawText, "-annotate 0x0+${xpos}+${ypos} \"$title\"";

my $num_rows = 2;
# ROWS 1 - 2 Laplacian field on gray surfaces.

my $gm_left_clr = "${tmpdir}/gm_phi_left.obj";
my $gm_right_clr = "${tmpdir}/gm_phi_right.obj";

`colour_object $gm_left $phi_left $gm_left_clr spectral 9.75 10.25`;
`colour_object $gm_right $phi_right $gm_right_clr spectral 9.75 10.25`;
unlink( $phi_left );
unlink( $phi_right );
  
foreach my $pos ('default', 'left', 'right') {
  print "Making left gm ${pos} surface\n" unless $quiet;
  make_hemi($gm_left_clr, "${tmpdir}/gm_left_$pos.rgb", $pos);
  push(@mont_args, "${tmpdir}/gm_left_$pos.rgb");
}
foreach my $pos ('top', 'bottom') {
  print "Making left/right gm ${pos} surface\n" unless $quiet;
  make_surface( $gm_left_clr, $gm_right_clr, "${tmpdir}/gm_${pos}.rgb", $pos );
  push(@mont_args, "${tmpdir}/gm_${pos}.rgb");
}

foreach my $pos ('flipped', 'right', 'left') {
  print "Making right gm ${pos} surface\n" unless $quiet;
  make_hemi($gm_right_clr, "${tmpdir}/gm_right_$pos.rgb", $pos);
  push(@mont_args, "${tmpdir}/gm_right_$pos.rgb");
}
foreach my $pos ('front', 'back') {
  print "Making left/right gm ${pos} surface\n" unless $quiet;
  make_surface( $gm_left_clr, $gm_right_clr, "${tmpdir}/gm_${pos}.rgb", $pos );
  push(@mont_args, "${tmpdir}/gm_${pos}.rgb");
}

unlink( $gm_left_clr );
unlink( $gm_right_clr );

# do the montage
print "Making montage\n" unless $quiet;
my $cmd = "montage -debug -tile 5x${num_rows} -background white " .
          "-geometry ${tilesize}x${tilesize}+1+1 " .
	  join(' ', @mont_args)." ${tmpdir}/mont.png";
print "$cmd\n" if $debug; `$cmd`;

# Add the title
print "Adding title\n" unless $quiet;
$cmd = "convert -box white -stroke green -pointsize 16 @DrawText ${tmpdir}/mont.png ${output}";
print "$cmd\n" if $debug; `$cmd`;

print "Done\n" unless $quiet;

# end of function

sub make_hemi {
  my ($surface, $temp_output, $pos) = @_;
  
  my $cmd = "";
  my $viewdir = "";
  if ($pos eq 'default') {
    $viewdir = "-view 0.77 -0.18 -0.6 0.55 0.6 0.55";
  } else {
    if ($pos eq 'flipped') {
      $viewdir = "-view -0.77 -0.18 -0.6 -0.55 0.6 0.55";
    } else {
      $viewdir = "-$pos";
    }
  }

  $cmd = "ray_trace -shadows -output ${temp_output} ${surface} -bg white -crop ${viewdir}";
  print "$cmd\n" if $debug; `$cmd`;
}

sub make_surface {
  my ($left_hemi, $right_hemi, $temp_output, $pos) = @_;
  
  my $cmd = "";
  my $viewdir = "";
  if ($pos eq 'default') {
    $viewdir = "";
  } else {
    $viewdir = "-$pos";
  }

  $cmd = "ray_trace -shadows -output ${temp_output} ${left_hemi} ${right_hemi} -bg white -crop ${viewdir}";
  print "$cmd\n" if $debug; `$cmd`;
}