SDL::GFX::Rotozoom

Section: User Contributed Perl Documentation (3)
Updated: 2021-01-27
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NAME

SDL::GFX::Rotozoom - rotation and zooming functions for surfaces

CONSTANTS

The constants are exported by default. You can avoid this by doing:

 use SDL::GFX::Rotozoom ();

and access them directly:

 SDL::GFX::Rotozoom::SMOOTHING_OFF;

or by choosing the export tags below:

Export tag: ':smoothing'

 SMOOTHING_OFF
 SMOOTHING_ON

METHODS

surface

 my $new_surface = SDL::GFX::Rotozoom::surface( $surface, $angle, $zoom, $smooth );

With "SDL::GFX::Rotozoom::surface" you have the opportunity to rotate and zoom a given surface. The surface will be rotated counter clockwise (in degrees). Pass "SMOOTHING_ON" or "SMOOTHING_OFF" in order to turn it on or off.

Note: The new surface (with $"zoom == 1") will usually be bigger than the source $surface.

Note: Note: new surface should be less than 16384 in width and height.

Example:

 use SDL;
 use SDL::Video;
 use SDL::Rect;
 use SDL::Surface;
 use SDL::GFX::Rotozoom;
 
 my $screen_width  = 640;
 my $screen_height = 480;
 
 SDL::init(SDL_INIT_VIDEO);
 
 my $screen  = SDL::Video::set_video_mode(800, 600, 32, SDL_SWSURFACE);
 my $picture = SDL::Video::load_BMP('test.bmp');
 
 my $rotated = SDL::GFX::Rotozoom::surface( $picture, 45, 0.8, SMOOTHING_ON );
 
 SDL::Video::blit_surface( $rotated, SDL::Rect->new(0, 0, $rotated->w, $rotated->h), 
                           $screen,  SDL::Rect->new(0, 0, 0, 0) );
 
 SDL::Video::update_rect( $screen, 0, 0, 0, 0 );
 
 sleep(2);

surface_xy

 my $new_surface = SDL::GFX::Rotozoom::surface_xy( $surface, $angle, $zoom_x, $zoom_y, $smooth );

Same as SDL::GFX::Rotozoom::surface but you can specify the zoomlevel for x and y separately.

surface_size

 my ($new_width, $new_height) = @{ SDL::GFX::Rotozoom::surface_size( $width, $height, $angle, $zoom ) };

"surface_size" will give you the width and height of an rotating/zoom operation for the given $width and $height. Helpful for knowing the surface size before actually do the rotating/zoom operation.

surface_size_xy

 my ($new_width, $new_height) = @{ SDL::GFX::Rotozoom::surface_size_xy( $width, $height, $angle, $zoom_x, $zoom_y ) };

Same as SDL::GFX::Rotozoom::surface_size but you can specify the zoomlevel for x and y separately.

zoom_surface

 my $new_surface = SDL::GFX::Rotozoom::zoom_surface( $surface, $zoom_x, $zoom_y, $smooth );

Same as SDL::GFX::Rotozoom::surface_xy except you can zoom only.

zoom_surface_size

 my ($new_width, $new_height) = SDL::GFX::Rotozoom::zoom_surface_size( $width, $height, $zoom_x, $zoom_y );

Same as SDL::GFX::Rotozoom::surface_size_xy except you can specify zoom only.

shrink_surface

 my $new_surface = SDL::GFX::Rotozoom::shrink_surface( $surface, $factor_x, $factor_y );

Specialized function for shrinking a surface.

rotate_surface_90_degrees

 my $new_surface = SDL::GFX::Rotozoom::rotate_surface_90_degrees( $surface, $num_clockwise_turns );

Rotating a surface $num_clockwise_turns-times.

AUTHORS

See ``AUTHORS'' in SDL.