#!/usr/bin/perl -w
#
#  "lines.pl" -- draws random colored lines using Logo, either with
#  a wrap of 1 (torus) or a wrap of 2 (reflection).
#
#  070116 by liverpole
#

# Strict
use strict;
use warnings;

# Libraries
use lib ".";
use Language::Logo;
use File::Basename;
use Data::Dumper;
use Getopt::Long;

# User-defined
my $nticks  = 100;      # Change color after nticks
my $tickcnt = 0;        # Number of ticks so far
my $color   = 'yellow'; # Starting pen color
my $size    = 2;        # Pen size
my $maxsize = 16;       # Maximum pen size
my $mindis  = 5;        # Minimum distance to advance
my $maxdis  = 50;       # Maximum distance to advance
my $width   = 500;      # Screen width
my $height  = 500;      # Screen height
my $dist    = 9999;     # Distance to move forward

# Globals
my $iam  = basename $0;
my $b_reflect = 0;
my $syntax = "
    syntax:  $iam  [switches]  <min angle>  <max angle>

    Tests round-world scenarios with lines which continuously change angles.
    Each time the color changes, a new random angle between <min angle> and
    <max angle> is chosen, and the line is rotated by that amount.

    Switches:
        -r ............ reflect mode (wrap 2) instead of torus mode (wrap 1)

    Try, for example, one of:

        $iam   29  31
        $iam   85  95
        $iam  170 190

";


# Command-line
my $result = GetOptions(
    "r" => \$b_reflect,
);
$result or die $syntax;
(my $minang = shift) or die $syntax;
(my $maxang = shift) or die $syntax;

# Main program

# Create Logo object
my $lo = new Logo(width => $width, height => $height);
my $wrap = $b_reflect? 2: 1;
$lo->command("wrap $wrap");
$lo->command("update 5");
$lo->command("pu");                      # Pen-up
$lo->command("setx random 0 800");       # Choose random x-coordinate
$lo->command("sety random 0 800");       # Choose random y-coordinate
$lo->command("rt random 0 360");         # Make a random turn
$lo->command("pendown; color $color");   # Start drawing
$lo->command("ht");                      # Hide turtle

while (1) {
    if (++$size > $maxsize) {
        $size = 1;
        $lo->command("cs");
    }
    $lo->command("ps $size");
    $lo->command("color random");
    $lo->command("fd $dist");
    $lo->command("rt random $minang $maxang");
}