view release on metacpan or  search on metacpan

lib/CAD/Calc.pm  view on Meta::CPAN

above copyright information) must remain intact on all copies of the
code.

Additionally, while the author is actively developing this code,
notification of any intended changes or extensions would be most helpful
in avoiding repeated work for all parties involved.  Please contact the
author with any such development plans.

=cut

=head1 Configuration

Used to set package global values such as precision.

=head2 import

Not called directly.  Triggered by the use() function.

  import(%options, @EXPORT_TAGS);

Example:

  use CAD::Calc (
  	-precision => 0.125,
	-angular   => 1.0e-6,
  	qw(
		seg_seg_intersection
		dist2d
		print_line
		)
	);

=cut
sub import {
	## print "import called with @_\n";
	local @ARGV = @_; # shame that Getopt::Long isn't structured better!
	use Getopt::Long ();
	Getopt::Long::GetOptions( '-',
		'precision=f' => \$linear_precision,
		'angular=f'   => \$angular_precision,
		) or croak("bad import arguments");
	## print "using $linear_precision for linear\n";
	## print "using $angular_precision for angular\n";
	$linr = Math::Round::Var->new($linear_precision);
	$angr = Math::Round::Var->new($angular_precision);
	## print "my linear rounding will be a ", ref($linr), "\n";
	## print "my angular rounding will be a ", ref($angr), "\n";
	CAD::Calc->export_to_level(1, @ARGV);
} # end subroutine import definition
########################################################################

=head1 Constants

=head2 pi

Returns the value of $CAD::Calc::pi

  pi;

=cut
sub pi() {
	return($pi);
} # end subroutine pi definition
########################################################################

=head1 Functions

These are all exported as options.

=head2 distdivide

Returns a list of point references resulting from dividing $line into
as many parts as possible which are at least $dist apart.

  @points = distdivide(\@line, $dist);

=cut
sub distdivide {
	my($line, $dist) = @_;
	$dist or croak("call to distdivide would cause divide by zero");
	my $ptA = NewVec(@{$line->[0]});
	my $ptB = NewVec(@{$line->[1]});
	my $seg = NewVec($ptB->Minus($ptA));
	my $length = $seg->Length();
	# optionally go for fewer points here?
	my $count = $length / $dist;
	$count = int($count);
	return(subdivide($line, $count));
} # end subroutine distdivide definition
########################################################################

=head2 subdivide

Returns a list of point references resulting from subdividing $line
into $count parts.  The list will be $count-1 items long, (does not
include $line->[0] and $line->[1]);

$line is of the form:  [ [x1, y1, z1], [x2, y2, z2] ] where z1 and z2
are optional.

  @points = subdivide($line, $count);

=cut
sub subdivide {
	my ($line, $count) = @_;
	$count || croak("cannot divide line into zero segments");
	my $ptA = NewVec(@{$line->[0]});
	my $ptB = NewVec(@{$line->[1]});
# 	print "line:  @$ptA -- @$ptB\n";
	my $seg = NewVec($ptB->Minus($ptA));
	my @points;
	for(my $st = 1; $st < $count; $st++) {
		push(@points, [$ptA->Plus( [ $seg->ScalarMult($st / $count) ] ) ] );
		}
	return(@points);
} # end subroutine subdivide definition
########################################################################

=head2 shorten_line

Shortens the line by the distances given in $lead and $tail.