View file File name : Animation.pod Content : =head1 NAME Tk::Animation - Display sequence of Tk::Photo images =for pm Tk/Animation.pm =for category Tk Image Classes =head1 SYNOPSIS use Tk::Animation my $img = $widget->Animation('-format' => 'gif', -file => 'somefile.gif'); $img->add_frame(@images); $img->start_animation; $img->start_animation( $period ); $img->next_image; $img->prev_image; $img->set_image( 0 .. $#frames ); $img->pause_animation; $img->resume_animation( $period ); $img->fast_forward( $multiplier ); $img->fast_reverse( $multiplier ); $img->stop_animation; $img->set_disposal_method( $boolean ); =head1 DESCRIPTION In the simple case when C<Animation> is passed a GIF89 style GIF with multiple 'frames', it will build an internal array of C<Photo> images. The C<add_frame> method adds images to the sequence. It is provided to allow animations to be constructed from separate images. All images must be C<Photo>s and should all be the same size. C<start_animation($period)> then initiates a C<repeat> with specified I<$period> to sequence through these images. As for raw C<repeat> I<$period> is in milliseconds, for a 50Hz monitor it should be at least 20ms. If I<$period> is omitted it is determined from the GIF metadata (see below), or if this is not possible it defaults to 100 milliseconds. C<stop_animation> cancels the C<repeat> and resets the image to the first image in the sequence. For fine-grained control C<next_image> and C<prev_image> move one frame forward or backward. C<set_image> randomly positions the animation to a particular frame. C<pause_animation> pauses the movie and C<resume_animation> continues from the pause point. C<fast_forward> and C<fast_reverse> speed through the movie either forwards or backwards. $multiplier specifies how much faster the animation moves. If L<Image::Info> is installed, then the repeat period time and disposal method of GIF animations are determined from the GIF metadata directly. Otherwise the disposal method must be set manually by using C<set_disposal_method> (1 for blanking the previous images, 0 for leaving the previous images as is). The repeat period time may be given in the C<start_animation> method. =head1 NOTES C<set_disposal_method> was formerly known as C<blank> method, but the naming of this method was a mistake. If the disposal method is not set correctly, either by C<set_disposal_method> or by determining from the GIF metadata, then the following may happen: By default Animation leaves the previous movie frame in the animation photo. Many times overlaying subsequent frames produces a composite that looks blurred. =head1 BUGS This module should not depend on a module which is not declared as a dependency (Image::Info). The delays between images may vary in a GIF animation. This cannot be handled by this module yet. The handling of the various disposal methods is not correct. =cut