/ 
SDL-2.529_1
River stage two • 23 direct dependents • 25 total dependents
/ SDLx::Layer

NAME

SDLx::Layer - Storage object for surface and position information

CATEGORY

Extension

SYNOPSIS

use SDLx::Layer;
use SDLx::LayerManager;

use SDL::Image;
use SDL::Surface;
use SDL::Video;

# creating layers
my $layer1 = SDLx::Layer->new( SDL::Image::load('image1.png'), {userdata => '7'} );
my $layer2 = SDLx::Layer->new( SDL::Image::load('image2.png'), 100, 200, {userdata => '42'} );

# creating the manager that holds the layers
my $layermanager = SDLx::LayerManager->new();
$layermanager->add( $layer1 );
$layermanager->add( $layer2 );

my $display = # create your video surface here

$layer1->foreground;
printf( "%s\n", $layer1->behind->[0]->data->{userdata} ); # prints 42

DESCRIPTION

A layer (see SDLx::Layer) is an SDL::Surface, the position of the surface on screen and some additional information, e.g. ingame states.

METHODS

new

my $layer = SDLx::Layer->new( $surface );
my $layer = SDLx::Layer->new( $surface,                                   %data );
my $layer = SDLx::Layer->new( $surface, $pos_x,                           %data );
my $layer = SDLx::Layer->new( $surface, $pos_x, $pos_y,                   %data );
my $layer = SDLx::Layer->new( $surface, $pos_x, $pos_y, $clip_w,          %data );
my $layer = SDLx::Layer->new( $surface, $pos_x, $pos_y, $clip_w, $clip_h, %data );

This constructs the layer object. See how you can omit the position and dimension of the layer. The hash %data is for your use only. The layer object just pass it through.

index

my $index = $layer->index;

The method index represents the z-index ot this layer within its layermanager.

x

my $x = $layer->x;

This is a shortcut for $layer->pos->x.

y

my $y = $layer->y;

This is a shortcut for $layer->pos->y.

w

my $w = $layer->w;

This is a shortcut for $layer->clip->w.

h

my $h = $layer->h;

This is a shortcut for $layer->pos->h.

surface

my $surface = $layer->surface;
my $surface = $layer->surface( $new_surface );

Example:

SDL::Video::blit_surface( $layer->surface, $layer->clip, $destination_surface, $layer->pos );

This method let you retrive the current or set a new surface.

pos

my $rect = $layer->pos;

The method pos returns an SDL::Rect object. The pos x and y are stored there.

Example:

SDL::Video::blit_surface( $layer->surface, $layer->clip, $destination_surface, $layer->pos );

clip

my $rect = $layer->clip;

The method clip returns an SDL::Rect object. The clip width and height are stored there.

Example:

SDL::Video::blit_surface( $layer->surface, $layer->clip, $destination_surface, $layer->pos );

data

my %data = %{ $layer->data };
my %data = %{ $layer->data( %new_data) };

This method returns the hash %data. You can set %data by passing a hash.

ahead

my @layers = $layer->ahead;

This method returns all layers that are ahead of the given layer. Ahead means that a layer has a higher z-index and is blitted over the given layer.

Note: This method doesn't check for transparency. This will change in future versions.

behind

my @layers = $layer->behind;

This method returns all layers that are behind of the given layer. Behind means that a layer has a lower z-index and is blitted over the given layer.

Note: This method doesn't check for transparency. This will change in future versions.

attach

$layer->attach( $x, $y );

This function makes the given layer sticky to the mouse. If you move the mouse the layer will follow. The layermanager blits this layer at last, so they will appear on top of all layers.

$x and $y should be set to the coords of the mouse, e.g. the coords of the mouse click. If you omit $x and $y the layer obtains them via SDL::Events::get_mouse_state.

Note: The z-index is not changed for the given layer.

detach_xy

$layer->detach_xy( $x, $y );

detach_xy detaches the prevously attached layer to the given coords. The upper left corner of this layer will be at $x and $y.

foreground

$layer->foreground;

This method moves the given layer to the foreground so that it is blittet on top of the other layers.

BUGS

Report at sdlperl.ath.cx

SUPPORT

#sdl irc.perl.org

AUTHORS

See "AUTHORS" in SDL.

COPYRIGHT

This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.

The full text of the license can be found in the LICENSE file included with this module.

SEE ALSO

perl(1), SDL(2).