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#!/usr/local/bin/perl
use PGPLOT;
print "\n\nTesting Object-Oriented stuff...\n\n";
print "PGPLOT module version $PGPLOT::VERSION\n\n";
pgqinf("VERSION",$val,$len);
print "PGPLOT $val library\n\n";
$dev = "?" unless defined $dev; # "?" will prompt for device
pgbegin 9,$dev,1,1; pgwnad -100,100,-100,100;
pgpage; pgbox 'BC',0,0,'BC',0,0;
# Define some object classes
##############################################################
package Square;
use PGPLOT; # Square class needs PGPLOT
# Create a new Square - colour is first argument
sub new {
my $type = shift; # Ignore as we know we are a Square;
my $self = {}; # $self is ref to anonymous hash
my $colour = shift;
$colour = 2 unless defined($colour); # Default is red
$self->{'Colour'}=$colour;
$self->{'Xvertices'} = [-10, 10, 10,-10, -10]; # Initialise as square
$self->{'Yvertices'} = [-10,-10, 10, 10, -10];
bless $self;
}
# Method to plot a Square object at $x,$y
sub plot {
my $self = shift;
my($x,$y) = @_;
my(@xpts) = @{$self->{'Xvertices'}};
my(@ypts) = @{$self->{'Yvertices'}};
for (@xpts) { $_ = $_ + $x }
for (@ypts) { $_ = $_ + $y }
pgsci($self->{'Colour'}); pgpoly(scalar(@xpts), \@xpts, \@ypts);
pgsci(1); pgline(scalar(@xpts), \@xpts, \@ypts);
}
# Method to expand a Square object
sub expand {
my $self = shift;
my $fac = shift;
my $xpts = $self->{'Xvertices'};
my $ypts = $self->{'Yvertices'};
for (@$xpts) { $_ = $_ * $fac }
for (@$ypts) { $_ = $_ * $fac }
}
# Method to rotate a Square object
sub rotate {
my $self = shift;
my $angle = (shift)*(3.141592564/180);
my $x = $self->{'Xvertices'};
my $y = $self->{'Yvertices'};
my ($x2,$y2);
for($i=0; $i<=$#{$x}; $i++) {
$x2 = $$x[$i]*cos($angle) + $$y[$i]*sin($angle);
$y2 = -$$x[$i]*sin($angle) + $$y[$i]*cos($angle);
$$x[$i] = $x2; $$y[$i] = $y2;
}
}
##############################################################
package Triangle;
# Only difference is "new" method. Otherwise inherit
# all other properties from "Square";
@ISA = qw( Square );
# Create a new Triangle
sub new {
my $type = shift; # Ignore as we know we are a Square;
my $self = {}; # $self is ref to anonymous hash
my $colour = shift;
$colour = 3 unless defined($colour); # Default is green
$self->{'Colour'}=$colour;
$self->{'Xvertices'} = [-10, 10, 0, -10]; # Initialise as square
$self->{'Yvertices'} = [-10,-10, 5, -10];
bless $self;
}
##############################################################
# Now let's use these objects
package main;
print "\nTesting Square Objects...\n";
$shape1 = new Square;
# Plot first shape at 50,50;
print "Square plot method...\n";
$shape1->plot(50,50);
print "Square expand and rotate methods...\n";
$shape1->expand(2.3); # Make the shape bigger
$shape1->rotate(20); # Rotate the shape bigger
$shape1->plot(-20,-50);
print "Inheriting Square methods in Triangles...\n";
$shape2 = new Triangle;
$shape2->plot(-20,50);
$shape3 = new Triangle(4); # Blue triangle
$shape3->rotate(-15); $shape3->expand(1.5);
$shape3->plot(50,-50);
print "Fun isn't it?\n";
$len=1; # -w fudge
pgend;
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