libsdl-perl 2.540-5 / usr / lib / perl5 / pods / SDL / Image.pod

=pod

=head1 NAME

SDL::Image - Bindings for the SDL_Image library

=head1 DESCRIPTION

SDL::Image allows you to load many different format of images into memory as an SDL::Surface.

=head1 CATEGORY

Image

=head1 SUPPORTED FORMATS 

The following types are supported:

=over

=item TGA

TrueVision Targa (MUST have .tga) 

=item BMP

Windows Bitmap(.bmp) 

=item PNM

Portable Anymap (.pnm)
.pbm = Portable BitMap (mono)
.pgm = Portable GreyMap (256 greys)
.ppm = Portable PixMap (full color)

=item XPM

X11 Pixmap (.xpm) can be #included directly in code
This is NOT the same as XBM(X11 Bitmap) format, which is for monocolor images. 

=item XCF

GIMP native (.xcf) (XCF = eXperimental Computing Facility?)
This format is always changing, and since there's no library supplied by the GIMP project to load XCF, the loader may frequently fail to load much 
of any image from an XCF file. It's better to load this in GIMP and convert to a better supported image format. 

=item PCX

ZSoft IBM PC Paintbrush (.pcx) 

=item GIF

CompuServe Graphics Interchange Format (.gif) 

=item JPG

Joint Photographic Experts Group JFIF format (.jpg or .jpeg) 

=item TIF

Tagged Image File Format (.tif or .tiff) 

=item LBM

Interleaved Bitmap (.lbm or .iff) FORM : ILBM or PBM(packed bitmap), HAM6, HAM8, and 24bit types are not supported. 

=item PNG

Portable Network Graphics (.png) 

=item XV

=item ICO

=item CUR

=back


=head1 LOADING METHODS

=head2 load

 my $surface = SDL::Image::load( $file );

$file Image file name to load a surface from. 
 
Load file for use as an image in a new L<SDL::Surface>. This actually calls L<SDL::Image::load_typed_rw|SDL::Image/"load_typed_rw">, with the 
file extension used as the type string. This can load all supported image files, including TGA as long as the filename ends with ".tga". It is 
best to call this outside of event loops, and rather keep the loaded images around until you are really done with them, as disk speed and image 
conversion to a surface is not that speedy.  

B<Note>: If the image format loader requires initialization, it will attempt to do that the first time it is needed if you have not already called 
L<SDL::Image::init|SDL::Image/"init"> to load support for your image format.

B<Note>: If the image format supports a transparent pixel, L<SDL::Image> will set the colorkey for the surface. You can enable RLE acceleration on 
the surface afterwards by calling:

L<SDL::Video::set_color_key|SDL::Video/"set_color_key">
 
  my $image = SDL::Image::load( $some_png_file );
  SDL::Video::set_color_key($image, SDL_RLEACCEL, $image->format->colorkey);

=head3 Return

An image as a L<SDL::Surface>. NULL is returned on errors, such as no support built for the image, or a file reading error. Use 
L<SDL::get_error|SDL/"get_error"> to get cause of error.

=head2 load_typed_rw

  SDL::Image::load_typed_rw($src, $freesrc, $type);

=over

=item src

The source L<SDL::RWops> as a pointer. The image is loaded from this. 

=item freesrc

A non-zero value mean is will automatically close/free the src for you. Since SDL Perl cannot handle the memory inside this function you would most 
likely want 1 here.

=item type

A string that indicates which format type to interpret the image as.

Here is a list of the currently recognized strings (case is not important):

=over

=item "BMP"

=item "CUR"

=item "GIF"

=item "ICO"

=item "JPG"

=item "LBM"

=item "PCX"

=item "PNG"

=item "PNM"

=item "TGA"

=item "TIF"

=item "XCF"

=item "XPM"

=item "XV"

=back

=back 

Load src for use as a surface. This can load all supported image formats. This method does not guarantee that the format specified by type is the 
format of the loaded image, except in the case when TGA format is specified (or any other non-magicable format in the future). Using SDL_RWops is 
not covered here, but they enable you to load from almost any source.

B<Note>: If the image format loader requires initialization, it will attempt to do that the first time it is needed if you have not already called 
L<SDL::Image::init|SDL::Image/"init"> to load support for your image format.

B<Note>: If the image format supports a transparent pixel, L<SDL::Image> will set the colorkey for the surface. You can enable RLE acceleration on 
the surface afterwards by calling: L<SDL::Video::set_color_key|SDL::Video/"set_color_key">

=head3 Transparency 

  use SDL;
  use SDL::RWOps;
  use SDL::Image;

  my $file2 = SDL::RWOps->new_file("test/data/menu.png", "rb");
  my $image = SDL::Image::load_typed_rw($file2, 1, "PNG");

  SDL::Video::set_color_key($image, SDL_RLEACCEL, $image->format->colorkey);

=head3 Return 

The image as a new L<SDL::Surface>. NULL is returned on errors. 
 
=head2 is_[TYPE]

Test for valid, supported image files:

=over

=item is_ICO

=item is_CUR

=item is_PNG

=item is_BMP

=item is_GIF

=item is_JPG

=item is_LBM

=item is_PCX

=item is_PNM 

=item is_TIF

=item is_XCF

=item is_XPM

=item is_XV

=back

These functions take a L<SDL::RWOps> as a parameter.

=head3 Return

1 if the image is a valid [TYPE]  and the [TYPE] format support is compiled into SDL_image. 0 is returned otherwise. 

=head3 Example

 use SDL::RWOps;
 use SDL::Image;

 my $file = SDL::RWOps->new_file("file", "rb");
 
 print "Image is BMP" if ( SDL::is_BMP );

=head2 load_[TYPE]_rw

Specific loader for known formats:

=over

=item load_ICO_rw

=item load_CUR_rw

=item load_PNG_rw

=item load_BMP_rw

=item load_GIF_rw

=item load_JPG_rw

=item load_LBM_rw

=item load_PCX_rw

=item load_PNM_rw 

=item load_TIF_rw

=item load_XCF_rw

=item load_XPM_rw

=item load_XV_rw

=back

These functions take a L<SDL::RWop> as a parameter

=head3 Return

The image as a new L<SDL::Surface>. NULL is returned on errors, like if the [TYPE] is not supported, or a read error.

=head3 Example

 use SDL;
 use SDL::RWOps;
 use SDL::Image;

 my $file = SDL::RWOps->new_file("file.png", "rb");  

 my $image = SDL::Image::load_PNG_rw($file);
 
 die SDL::get_error if (!$image);  
 
=head2 read_XPM_from_array

 my $picture = SDL::Image::read_XPM_from_array(\@XPM, $width);

This functions takes the reference of an array in the valid @XPM format. Also the $width of the XPM image.

=head3 Return

The image as a new L<SDL::Surface>. NULL is returned on errors, like if XPM is not supported, or a read error. 

=head3 Example

	my @XPM= (
	'30 30 9 1',
	' 	c #FFFFFF',
	'.	c #EFEFEF',
	'+	c #CFCFCF',
	'@	c #9F9F9F',
	'#	c #808080',
	'$	c #505050',
	'%	c #202020',
	'&	c #000000',
	'*	c #303030',
	'                              ',
	'                              ',
	'                              ',
	'                              ',
	'                              ',
	'                              ',
	'                              ',
	'                              ',
	'                              ',
	'           .+@##@+.           ',
	'          .@$%&&%$@.          ',
	'         .@*&&&&&&*@.         ',
	'         +$&&&&&&&&$+         ',
	'         @%&&&&&&&&%@         ',
	'         #&&&&&&&&&&#         ',
	'         #&&&&&&&&&&#         ',
	'         @%&&&&&&&&%@         ',
	'         +$&&&&&&&&$+         ',
	'         .@*&&&&&&*@.         ',
	'          .@$%&&%$@.          ',
	'           .+@##@+.           ',
	'                              ',
	'                              ',
	'                              ',
	'                              ',
	'                              ',
	'                              ',
	'                              ',
	'                              ',
	'                              ',);
	
	my $picture = SDL::Image::read_XPM_from_array(\@XPM, 30);

=head1 MISC METHODS

=head2 linked_version

Provides the version of linked sdl_image library.

=head3 Return

Returns a L<SDL::Version> object

=head3 Example

	my $version = SDL::Image::linked_version();
	print $version->major.' '.$version->minor.' '.$version->patch;

=head2 init

B<For version SDL_image 1.2.10 and up>

=head3 Flags

bitwise OR'd set of image formats to support by loading a library now. The values you may OR together to pass in are: 

=over

=item IMG_INIT_JPG 

=item IMG_INIT_PNG 

=item IMG_INIT_TIF

=back

Initialize by loading support as indicated by the flags, or at least return success if support is already loaded. You may call this multiple times, 
which will actually require you to call IMG_Quit just once to clean up. You may call this function with a 0 to retrieve whether support was built-in 
or not loaded yet.

B<Note>: to load JPG, PNG, and/or TIF images you can call IMG_Init with the right IMG_INIT_* flags OR'd together before you program gets busy, to 
prevent a later hiccup while it loads the library, and to check that you do have the support that you need before you try and use it.

B<Note>: No initialization is needed nor performed when using the SDL::Image::is_JPG, SDL::Image::is_PNG, and SDL::Image::is_TIF functions.

B<Note>: this function does not always set the error string, so do not depend on SDL::Image::get_error being meaningful all the time.  

=head3 Return

A bitmask of all the currently inited image loaders.

=head3 Example

  use SDL::Image;
  my $flags = IMG_INIT_JPG | IMG_INIT_PNG | IMG_INIT_JPG;
  my $inited = SDL::Image::init($flags);

=head2 quit

B<For version SDL_image 1.2.10 and up>

This function cleans up all dynamically loaded library handles, freeing memory. If support is required again it will be initialized again, either 
by L<SDL::Image::init|SDL::Image/"init"> or loading an image with dynamic support required. You may call this function when 
L<SDL::Image::load|SDL::Image/"load"> functions are no longer needed for the JPG, PNG, and TIF image formats. You only need to call this function 
once, no matter how many times L<SDL::Image::init|SDL::Image/"init"> was called. 

=head3 Example

 use SDL::Image;
 SDL::Image::init(IMG_INIT_JPG); #loads JPG support
 SDL::Image::load("file.png"); #loads PNG support
 SDL::Image::quit(); #unloads everything

=head2 set_error

Same as L<SDL::set_error|SDL/"set_error">

=head2 get_error

Same as L<SDL::get_error|SDL/"get_error">

=head1 SEE ALSO

L<SDL>, L<SDL::Surface>, L<SDL::Video>, L<SDL::RWOps>

=head1 AUTHORS

See L<SDL/AUTHORS>.

=cut