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