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<!-- INDEX START -->
<h3 id="TOP">Index</h3>

<ul><li><a href="#NAME">NAME</a></li>
<li><a href="#CATEGORY">CATEGORY </a></li>
<li><a href="#SYNOPSIS">SYNOPSIS</a></li>
<li><a href="#DESCRIPTION">DESCRIPTION</a></li>
<li><a href="#METHODS">METHODS</a>
<ul><li><a href="#new">new</a></li>
<li><a href="#add">add</a></li>
<li><a href="#layers">layers</a></li>
<li><a href="#layer">layer</a></li>
<li><a href="#length">length</a></li>
<li><a href="#blit">blit</a></li>
<li><a href="#by_position">by_position</a></li>
<li><a href="#ahead">ahead</a></li>
<li><a href="#behind">behind</a></li>
<li><a href="#attach">attach</a></li>
<li><a href="#detach_xy">detach_xy</a></li>
<li><a href="#detach_back">detach_back</a></li>
<li><a href="#foreground">foreground</a></li>
</ul>
</li>
<li><a href="#BUGS">BUGS</a></li>
<li><a href="#SUPPORT">SUPPORT</a></li>
<li><a href="#AUTHORS">AUTHORS</a></li>
<li><a href="#COPYRIGHT">COPYRIGHT</a></li>
<li><a href="#SEE_ALSO">SEE ALSO</a>
</li>
</ul><hr />
<!-- INDEX END -->

<h1 id="NAME">NAME</h1><p><a href="#TOP" class="toplink">Top</a></p>
<div id="NAME_CONTENT">
<p>SDLx::LayerManager - Extension for managing layers in a 2D world</p>

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<h1 id="CATEGORY">CATEGORY </h1><p><a href="#TOP" class="toplink">Top</a></p>
<div id="CATEGORY_CONTENT">
<p>Extension</p>

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<h1 id="SYNOPSIS">SYNOPSIS</h1><p><a href="#TOP" class="toplink">Top</a></p>
<div id="SYNOPSIS_CONTENT">
<pre>  use SDLx::Layer;
  use SDLx::LayerManager;

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

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

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

  my $display = # create your video surface here

  $layermanager-&gt;blit( $display );

  # accessing the layer at point(x,y)
  print( $layermanager-&gt;by_position( 150, 200 )-&gt;data-&gt;{userdata} ); # should print '42'

</pre>

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<h1 id="DESCRIPTION">DESCRIPTION</h1><p><a href="#TOP" class="toplink">Top</a></p>
<div id="DESCRIPTION_CONTENT">
<p>SDLx::LayerManager is a package to handle a bunch of layers. A layer (see SDLx::Layer) is an SDL::Surface, the position of the surface on screen and some additional information.</p>
<p>The layermanager gives you the opportunity to obtain the layer at a given point on screen and get the layers that are ahead or behind a layer.</p>
<p>You will even be able to attach one or more layers to the mouse, e.g. for simulation some drag&amp;drop functionality.</p>

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<h1 id="METHODS">METHODS</h1><p><a href="#TOP" class="toplink">Top</a></p>
<div id="METHODS_CONTENT">

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<h2 id="new">new</h2>
<div id="new_CONTENT">
<pre>  my $layermanager = SDLx::LayerManager-&gt;new();

</pre>
<p>This creates your layermanager object. It doesn't take any parameters.</p>

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<h2 id="add">add</h2>
<div id="add_CONTENT">
<pre>  $layermanager-&gt;add( $layer );
  $layermanager-&gt;add( SDLx::Layer-&gt;new( $surface, $x, $y, $options ) );

</pre>
<p>Call <code>add</code> to push an SDLx::Layer object to the layermanager.</p>

</div>
<h2 id="layers">layers</h2>
<div id="layers_CONTENT">
<pre>  my @layers = @{ $layermanager-&gt;layers };
  my $first_layer = $layermanager-&gt;layers-&gt;[0];

</pre>
<p>The method <code>layers</code> returns all layers that were added before.</p>

</div>
<h2 id="layer">layer</h2>
<div id="layer_CONTENT">
<pre>  my $layer = $layermanager-&gt;layer( $index );

</pre>
<p>To obtain only one layer at index <code>$index</code> use this function. <code>$index</code> ranges from <code>0</code> to <code>lenght - 1</code>.</p>

</div>
<h2 id="length">length</h2>
<div id="length_CONTENT">
<pre>  my $length = $layermanager-&gt;length();

</pre>
<p>This method returns the count of the added layers.</p>

</div>
<h2 id="blit">blit</h2>
<div id="blit_CONTENT">
<pre>  $layermanager-&gt;blit( $surface );

</pre>
<p>This method blits all layers to the surface (e.g. your video surface).</p>

</div>
<h2 id="by_position">by_position</h2>
<div id="by_position_CONTENT">
<pre>  my $layer = $layermanager-&gt;by_position( $x, $y );

</pre>
<p><code>by_position</code> returns the <code>SDLx::Layer</code> object at point <code>$x $y</code>, which is not fully transparent at this pixel.</p>

</div>
<h2 id="ahead">ahead</h2>
<div id="ahead_CONTENT">
<pre>  my @layers = @{ $layermanager-&gt;ahead( $index ) };

</pre>
<p>This method returns all layers that are ahead of the given layer indicated by <code>$index</code>.
Ahead means that a layer has a higher z-index and is blitted over the given layer.</p>
<p><strong>Note</strong>: This method doesn't check for transparency. This will change in future versions.</p>

</div>
<h2 id="behind">behind</h2>
<div id="behind_CONTENT">
<pre>  my @layers = @{ $layermanager-&gt;behind( $index ) };

</pre>
<p>This method returns all layers that are behind of the given layer indicated by <code>$index</code>.
Behind means that a layer has a lower z-index and is blitted before the given layer.</p>
<p><strong>Note</strong>: This method doesn't check for transparency. This will change in future versions.</p>

</div>
<h2 id="attach">attach</h2>
<div id="attach_CONTENT">
<pre>  $layermanager-&gt;attach( $layer,  $x, $y );
  $layermanager-&gt;attach( @layers, $x, $y );

</pre>
<p>This function makes the given layer(s) sticky to the mouse. If you move the mouse the layer(s) will follow.
The layermanager blits these layers at last, so they will appear on top of all layers.</p>
<p><code>$x</code> and <code>$y</code> should be set to the coords of the mouse, e.g. the coords of the mouse click.
If you omit <code>$x</code> and <code>$y</code> the layermanager obtains them via SDL::Events::get_mouse_state.</p>
<p><strong>Note</strong>: The z-index is not changed for the given layers.</p>

</div>
<h2 id="detach_xy">detach_xy</h2>
<div id="detach_xy_CONTENT">
<pre>  $layermanager-&gt;detach_xy( $x, $y );

</pre>
<p><code>detach_xy</code> detaches the prevously attached layers to the given coords. The upper left corner of the backmost layer will be at <code>$x</code> and <code>$y</code>.
The other layers are positioned relative to the backmost layer just like before.</p>

</div>
<h2 id="detach_back">detach_back</h2>
<div id="detach_back_CONTENT">
<pre>  $layermanager-&gt;detach_back( );

</pre>
<p><code>detach_back</code> detaches the prevously attached layers back to the position where they were attached.</p>

</div>
<h2 id="foreground">foreground</h2>
<div id="foreground_CONTENT">
<pre>  $layermanager-&gt;foreground( $layer );
  $layermanager-&gt;foreground( @layers );

</pre>
<p>This method moves the given layer(s) to the foreground so that they are blittet on top of the other layers.</p>

</div>
<h1 id="BUGS">BUGS</h1><p><a href="#TOP" class="toplink">Top</a></p>
<div id="BUGS_CONTENT">
<p>Report at sdlperl.ath.cx</p>

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<h1 id="SUPPORT">SUPPORT</h1><p><a href="#TOP" class="toplink">Top</a></p>
<div id="SUPPORT_CONTENT">
<p>#sdl irc.perl.org</p>

</div>
<h1 id="AUTHORS">AUTHORS</h1><p><a href="#TOP" class="toplink">Top</a></p>
<div id="AUTHORS_CONTENT">
<p>See <a href="/SDL.html#AUTHORS">/SDL.html#AUTHORS</a>.</p>

</div>
<h1 id="COPYRIGHT">COPYRIGHT</h1><p><a href="#TOP" class="toplink">Top</a></p>
<div id="COPYRIGHT_CONTENT">
<p>This program is free software; you can redistribute
it and/or modify it under the same terms as Perl itself.</p>
<p>The full text of the license can be found in the
LICENSE file included with this module.</p>





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<h1 id="SEE_ALSO">SEE ALSO</h1><p><a href="#TOP" class="toplink">Top</a></p>
<div id="SEE_ALSO_CONTENT">
<p>perl(1), SDL(2).</p>

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</div>