#! /usr/bin/env perl
#
# Demo x15 for PLplot PDL bindings
#
# Shade plot demo
#
# Copyright (C) 2004  Rafael Laboissiere
#
# This file is part of PLplot.
#
# PLplot is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Library Public License as published
# by the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# PLplot is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU Library General Public License for more details.
#
# You should have received a copy of the GNU Library General Public License
# along with PLplot; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA


use PDL;
use PDL::Graphics::PLplot;

use constant XPTS => 35;    # Data points in x
use constant YPTS => 46;    # Data points in y

$z = zeroes (XPTS, YPTS);
my $zmin, $zmax;

# Function prototypes

sub plot1 ();
sub plot2 ();
sub f2mnmx ($);
sub cmap1_init1	();
sub cmap1_init2	();

# main
#
# Does a variety of shade plots

sub main {

  # Parse and process command line arguments

  plParseOpts (\@ARGV, PL_PARSE_SKIP | PL_PARSE_NOPROGRAM);

  # Set up color map 0
  #
  #  plscmap0n(3);
  #


  # Set up color map 1

  cmap1_init2 ();

  # Initialize plplot

  plinit ();

  # Set up data array

  my $xx = (sequence (XPTS) - (XPTS / 2)) / (XPTS / 2);
  my $yy = (sequence (YPTS) - (YPTS / 2)) / (YPTS / 2) - 1.0;
  for (my $i = 0; $i < XPTS; $i++) {
    my $xi = $xx->index ($i);
    for (my $j = 0; $j < YPTS; $j++) {
      my $yi = $yy->index ($j);
      $z->slice ("$i,$j") .= $xi ** 2 - $yi ** 2
        + ($xi - $yi) / ($xi * $xi + $yi ** 2 + 0.1);
    }
  }

  ($zmin, $zmax) = f2mnmx ($z);

  plot1 ();
  plot2 ();

  plend();

}

# cmap1_init1
#
# Initializes color map 1 in HLS space

sub cmap1_init1 () {
  my $i = pdl [0,       # left boundary
               0.45,    # just before center
               0.55,    # just after center
               1];      # right boundary

  my $h = pdl [260,     # hue -- low: blue-violet
               260,     # only change as we go over vertex
               20,      # hue -- high: red
               20];     # keep fixed

  my $l;
  if (1) {
    $l = pdl [0.5,      # lightness -- low
              0.0,      # lightness -- center
              0.0,      # lightness -- center
              0.5];     # lightness -- high
  } else {
    plscolbg (255, 255, 255);
    $l = pdl [0.5,      # lightness -- low
              1.0,      # lightness -- center
              1.0,      # lightness -- center
              0.5];     # lightness -- high
  }
  my $s = pdl [1,       # maximum saturation
               1,       # maximum saturation
               1,       # maximum saturation
               1];      # maximum saturation

  plscmap1l (0, $i, $h, $l, $s, pdl ([]));
}

# cmap1_init2
#
# Initializes color map 1 in HLS space

sub cmap1_init2 () {
  my $i = pdl [0,       # left boundary
               0.45,    # just before center
               0.55,    # just after center
               1];      # right boundary

  my $h = pdl [260,     # hue -- low: blue-violet
               260,     # only change as we go over vertex
               20,      # hue -- high: red
               20];     # keep fixed

  my $l;
  if (1) {
    $l = pdl [0.6,      # lightness -- low
              0.0,      # lightness -- center
              0.0,      # lightness -- center
              0.6];     # lightness -- high
  } else {
    plscolbg (255, 255, 255);
    $l = pdl [0.5,      # lightness -- low
              1.0,      # lightness -- center
              1.0,      # lightness -- center
              0.5];     # lightness -- high
  }
  my $s = pdl [1,       # maximum saturation
               0.5,     # maximum saturation
               0.5,     # maximum saturation
               1];      # maximum saturation

  plscmap1l (0, $i, $h, $l, $s, pdl ([]));
}

# plot1
#
# Illustrates a single shaded region

sub plot1 () {
  my $sh_cmap = 0;
  my $min_color = 0;
  my $min_width = 0;
  my $max_color = 0;
  my $max_width = 0;

  pladv (0);
  plvpor (0.1, 0.9, 0.1, 0.9);
  plwind (-1.0, 1.0, -1.0, 1.0);

  # Plot using identity transform

  my $shade_min = $zmin + ($zmax - $zmin) * 0.4;
  my $shade_max = $zmin + ($zmax - $zmin) * 0.6;
  my $sh_color = 7;
  my $sh_width = 2;
  my $min_color = 9;
  my $max_color = 2;
  my $min_width = 2;
  my $max_width = 2;

  plpsty (8);
  plshade1 ($z, -1, 1, -1, 1,
            $shade_min, $shade_max, $sh_cmap, $sh_color, $sh_width,
            $min_color, $min_width, $max_color, $max_width,
            1, "", "", 0);

  plcol0 (1);
  plbox (0.0, 0, 0.0, 0, "bcnst", "bcnstv");
  plcol0 (2);
  pllab ("distance", "altitude", "Bogon flux");
}

# plot2
#
# Illustrates multiple adjacent shaded regions, using different fill
# patterns for each region

sub plot2 () {
  my $sh_cmap = 0;
  my $min_color = 0;
  my $min_width = 0;
  my $max_color = 0;
  my $max_width = 0;
  my $sh_width = 2;

  pladv (0);
  plvpor (0.1, 0.9, 0.1, 0.9);
  plwind (-1.0, 1.0, -1.0, 1.0);

  # Plot using identity transform

    for (my $i = 0; $i < 10; $i++) {
      my $shade_min = $zmin + ($zmax - $zmin) * $i / 10.0;
      my $shade_max = $zmin + ($zmax - $zmin) * ($i + 1) / 10.0;
      my $sh_color = $i + 6;
      plpsty (($i + 2) % 8 + 1);

      plshade1 ($z, -1, 1, -1, 1,
                $shade_min, $shade_max, $sh_cmap, $sh_color, $sh_width,
                $min_color, $min_width, $max_color, $max_width,
                1, "", "", 0);
    }

  plcol0 (1);
  plbox (0.0, 0, 0.0, 0, "bcnst", "bcnstv");
  plcol0 (2);
  pllab ("distance", "altitude", "Bogon flux");
}

# f2mnmx
#
# Returns min & max of input 2d array

sub f2mnmx ($) {
  my $f = shift;
  return (min ($f), max ($f));
}

main ();
