=pod

=head1 NAME

SDL::Mixer::Groups - Audio channel group functions

=head1 CATEGORY

Mixer

=head1 METHODS

=head2 reserve_channels

 my $reserved = SDL::Mixer::Groups::reserve_channels( $num );

C<$num> is the number of channels to reserve from default mixing. Zero removes all reservations. 

Reserve C<$num> channels from being used when playing samples when passing in C<-1> as a channel number to playback functions. 
The channels are reserved starting from channel C<0> to C<$num-1>. Passing in zero will unreserve all channels. Normally SDL_mixer starts 
without any channels reserved.

The following functions are affected by this setting: 

=over 4

=item *

L<SDL::Mixer::Channels::play_channel|SDL::Mixer::Channels/"play_channel">

=item *

L<SDL::Mixer::Channels::play_channel_timed|SDL::Mixer::Channels/"play_channel_timed">

=item *

L<SDL::Mixer::Channels::fade_in_channel|SDL::Mixer::Channels/"fade_in_channel">

=item *

L<SDL::Mixer::Channels::fade_in_channel_timed|SDL::Mixer::Channels/"fade_in_channel_timed">

=back

Returns: The number of channels reserved. Never fails, but may return less channels than you ask for, depending on the number of channels 
previously allocated (see L<SDL::Mixer::Channels::allocate_channels|SDL::Mixer::Channels/"allocate_channels">).

=head2 group_channel

 my $grouped = SDL::Mixer::Groups::group_channel( $channel, $group );

Add a channel to group id (any positive integer), or reset it's group to the default group by passing (-1).

Returns: True(1) on success. False(0) is returned when the channel specified is invalid.

=head2 group_channels

 my $grouped = SDL::Mixer::Groups::group_channels( $from_channel, $to_channel, $group );

Add a range of channels to group id (any positive integer), or reset their group to the default group by passing (-1).

Returns: The number of affected channels.

=head2 group_available

 my $channel = SDL::Mixer::Groups::group_count( $group );

C<group_newer> returns the first available channel of this group.

=head2 group_count

 my $channels = SDL::Mixer::Groups::group_count( $group );

C<group_newer> returns the number of channels in this group.

=head2 group_oldest

 my $channel = SDL::Mixer::Groups::group_oldest( $group );

C<group_newer> returns the channel number which started to play at first.

=head2 group_newer

 my $channel = SDL::Mixer::Groups::group_newer( $group );

C<group_newer> returns the channel number which started to play at last.

=head2 fade_out_group

 SDL::Mixer::Groups::fade_out_group( $group, $ms );

Fades out the channels by the given group id. The fade-out-time is specified by C<$ms>.

Returns the number of affected channels.

=head2 halt_group

 SDL::Mixer::Groups::hals_group( $group );

Halts the channels by the given group id.

Returns C<0>.

=head1 AUTHORS

See L<SDL/AUTHORS>.

=cut