#!/usr/bin/perl -w
# filename: makeiv.pl
# author:   Marvin Simkin
# date:     2002-10-21
# purpose:  make VRML 1 ".iv" files from instructions

# syntax:   makeiv.pl < pic.draw > pic.iv
# pic.draw  drawing instructions
# pic.iv    VRML 1.0 drawing

# NOTE:
# This originally only drew lines but was expanded.
# The goal of the data format is to make it possible to describe an object
# in a one-line instruction (e.g. draw a line from point A to point B)
# and to set defaults that apply to all subsequent objects (e.g. color red).

# You can have one "word" per line, or multiple "words" separated by ;
# A word describing an object has a colon, such as "line:X1,Y1,Z1,X2,Y2,Z2".
# This immediately causes the object to be created with existing colors etc.
# Or a word can set a value with an equal sign, such as "color=R G B".
# When a word changes a value it applies to all subsequent instructions.

# Input data format
# color=1 0 0
# linewidth=3
# line:X1,Y1,Z1,X2,Y2,Z2
# line:X1,Y1,Z1,X2,Y2,Z2;line:X1,Y1,Z1,X2,Y2,Z2
# color=0 0 1
# line:X1,Y1,Z1,X2,Y2,Z2
# triangle:X1,Y1,Z1,X2,Y2,Z2,X3,Y3,Z3
# line:X1,Y1,Z1,X2,Y2,Z2
# linewidth=1;line:X1,Y1,Z1,X2,Y2,Z2
# color=0.2 0.2 0.2;line:X1,Y1,Z1,X2,Y2,Z2
# fontname=Times-Roman;fontsize=12;fontjust=CENTER
# text:X1,Y1,Z1,whatever you want to say here

# ENHANCEMENT:
# Allow lines with more than two points.
# This would be MUCH more efficient.
# e.g. line:X1,Y1,Z1,X2,Y2,Z2,X3,Y3,Z3...
#
# Modify other programs to output longer lines.


# INITIALIZE:
my $LineWidth;
$LineWidth = 3;

my $Color;
$Color = '0.2 0.2 0.2';

my $FontName;
$FontName = 'Times-Roman';

my $FontSize;
$FontSize = 12;

my $FontJust;
$FontJust = 'CENTER';


print "#Inventor V2.0 ascii\n";
print "\n";
print "# generated by $0\n";
print "\n";
print "\n";

# SUBROUTINES:
use strict;

sub PlotLine {
  my $Word;
  ($Word) = @_;

  # this "word" had better be X1,Y1,Z1,X2,Y2,Z2
  my $X1;
  my $Y1;
  my $Z1;
  my $X2;
  my $Y2;
  my $Z2;
  ($X1, $Y1, $Z1, $X2, $Y2, $Z2) = split (/,/, $Word);

# NOTE about BaseColor
# specify colors for lines in order plotted

# NOTE about IndexedLineSet
# think of this as pen instructions
# drop pen at point 1, drawto 2, 3...
# to pick up pen use -1
#   coordIndex [ 0, 1 ]
#
# THE FOLLOWING VRML 1 INSTRUCTIONS WERE DROPPED
# SEEM TO HAVE NO PRACTICAL EFFECT ON WHAT I'M DOING
# LightModel {
#   model BASE_COLOR
# }
# MaterialBinding {
#   value PER_PART
# }
# LightModel {
#   model PHONG
# }
# MaterialBinding {
#   value OVERALL
# }


  print qq|
Separator {
  DrawStyle {
    lineWidth $LineWidth
  }
  Coordinate3 {
    point [
      $X1 $Y1 $Z1,
      $X2 $Y2 $Z2
    ]
  }
  BaseColor {
    rgb [ 
      $Color
    ]
  }
  IndexedLineSet {
    coordIndex [ 
      0, 1
    ]
  }
}
|; # end of print qq|

} # end of sub PlotLine

sub PlotTriangle {
  my $Word;
  ($Word) = @_;

  # this "word" had better be X1,Y1,Z1,X2,Y2,Z2,X3,Y3,Z3
  my $X1;
  my $Y1;
  my $Z1;
  my $X2;
  my $Y2;
  my $Z2;
  my $X3;
  my $Y3;
  my $Z3;
  ($X1, $Y1, $Z1, $X2, $Y2, $Z2, $X3, $Y3, $Z3) = split (/,/, $Word);

  print qq|
Separator {
  Coordinate3 {
    point [
      $X1 $Y1 $Z1,
      $X2 $Y2 $Z2,
      $X3 $Y3 $Z3
    ]
  }
  BaseColor {
    rgb [ 
      $Color
    ]
  }
  IndexedFaceSet {
    coordIndex [ 
      0, 1, 2
    ]
  }
}
|; # end of print qq|

} # end of sub PlotLine


sub PlotText {
  my $Word;
  ($Word) = @_;

  # Expected format: X1,Y1,Z1,whatever you want to say here
  # Due to the syntax the text cannot contain ; , " or newline
  my $X1;
  my $Y1;
  my $Z1;
  my $Text;
  ($X1, $Y1, $Z1, $Text) = split (/,/, $Word);


  print qq|
Separator {
  Font {
    name "$FontName"
    size $FontSize
  }
  Transform {
    translation $X1 $Y1 $Z1
    rotation 0 0 1 0
  }
  Text3 {
    string "$Text"
    justification $FontJust
  }
}
|; # end of print qq|

} # end of sub PlotText

# ARGUMENTS:

# MAINLINE:
my $Line;
while ($Line = <>) {
  chomp $Line;

  # a "word" is anything separated by semicolons
  my @Word;
  @Word = split (/;/, $Line);
  my $Word;
  foreach $Word (@Word) {
#   print STDERR "Processing '$Word'\n";

    # some words may set variables
    if ($Word =~ /=/) {
      # parse VAR=VALUE
      my $Var;
      my $Value;
      ($Var, $Value) = split (/=/, $Word, 2);

      if ($Var eq 'color') {
        $Color = $Value;
      } elsif ($Var eq 'linewidth') {
        $LineWidth = $Value;
      } elsif ($Var eq 'fontname') {
        $FontName = $Value;
      } elsif ($Var eq 'fontsize') {
        $FontSize = $Value;
      } elsif ($Var eq 'fontjust') {
        $FontJust = $Value;
##    } elsif ($Var eq 'x') {
##      $X = $Value;
      } else {
        print STDERR "Unrecognized variable assignment: '$Word'\n";
      }

    # other words may specify objects
    } elsif ($Word =~ /:/) {
      # parse VAR=VALUE
      my $Var;
      my $Value;
      ($Var, $Value) = split (/:/, $Word, 2);

      if ($Var eq 'line') {
        &PlotLine ($Value);

      } elsif ($Var eq 'triangle') {
        &PlotTriangle ($Value);

      } elsif ($Var eq 'text') {
        &PlotText ($Value);

      } else {
        print STDERR "Unrecognized object name: '$Word'\n";
      }


    } else {
      print STDERR "Unrecognized instruction: '$Word'\n";
    }
  }
}