lib/SDL/Timer.pm

   1 #       Timer.pm
   2 #
   3 #       A package for manipulating SDL_Timer *
   4 #
   5 #       Copyright (C) 2002 David J. Goehrig
   6
   7 package SDL::Timer;
   8 use strict;
   9 use warnings;
  10 use Carp;
  11 use SDL;
  12
  13 sub new {
  14         my $proto = shift;
  15         my $class = ref($proto) || $proto;
  16         my $self = {};
  17         my $func = shift;
  18         my (%options) = @_;
  19
  20         verify(%options,qw/ -delay -times -d -t /);
  21
  22         croak "SDL::Timer::new no delay specified\n"
  23                 unless ($options{-delay});
  24         $$self{-delay} = $options{-delay} || $options{-d} || 0;
  25         $$self{-times} = $options{-times} || $options{-t} || 0;
  26         if ($$self{-times}) {
  27                 $$self{-routine} = sub { &$func($self); $$self{-delay} if(--$$self{-times}) };
  28         } else {
  29                 $$self{-routine} = sub { &$func; $$self{-delay}};
  30         }
  31         $$self{-timer} = SDL::NewTimer($$self{-delay},$$self{-routine});
  32         croak "Could not create timer, ", SDL::GetError(), "\n"
  33                 unless ($self->{-timer});
  34         bless $self,$class;
  35         return $self;
  36 }
  37
  38 sub DESTROY {
  39         my $self = shift;
  40         SDL::RemoveTimer($$self{-timer}) if ($$self{-timer});
  41         $$self{-timer} = 0;
  42 }
  43
  44 sub run {
  45         my ($self,$delay,$times) = @_;
  46         $$self{-delay} = $delay;
  47         $$self{-times} = $times;
  48         SDL::RemoveTimer($$self{-timer}) if ($$self{-timer});
  49         $$self{-timer} = SDL::AddTimer($$self{-delay},SDL::PerlTimerCallback,$$self{-routine});
  50 }
  51
  52 sub stop {
  53         my ($self) = @_;
  54         SDL::RemoveTimer($$self{-timer}) if ($$self{-timer});
  55         $$self{-timer} = 0;
  56 }
  57
  58 1;
  59
  60 __END__;
  61
  62 =pod
  63
  64
  65 =head1 NAME
  66
  67 SDL::Timer - a SDL perl extension to handle timers
  68
  69 =head1 SYNOPSIS
  70
  71   $timer = new SDL::Timer { print "tick"; 4000; } -delay => 4000;
  72
  73 =head1 DESCRIPTION
  74
  75 C<SDL::Timer> provides an abstract interface to the SDL::Timer
  76 callback code.  SDL::Timer::new requires a subroutine and a delay
  77 at which is the initial interval between the creation of the
  78 timer until the first call to the subroutine.  The subroutine
  79 must return a value which is the delay until the it is called again.
  80
  81 =head1 AUTHOR
  82
  83 David J. Goehrig
  84
  85 =head1 SEE ALSO
  86
  87 L<perl> L<SDL>
  88
  89 =pod