SDL::Surface

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

SDL::Surface - Graphic surface structure

SYNOPSIS

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

 # Create the main surface (display)
 SDL::init(SDL_INIT_VIDEO);
 my $display = SDL::Video::set_video_mode(640, 480, 16, SDL_SWSURFACE);

 # Create other surfaces attached to the $display.
 my $surface  = SDL::Surface->new(SDL_ASYNCBLIT | SDL_HWSURFACE, 640, 480, 16, 0, 0, 0, 0);
 my $surface2 = SDL::Surface->new_from($surface, 100, 100, 8, 0, 0, 0, 0);

DESCRIPTION

An "SDL_Surface" defines a surfaceangular area of pixels.

CONSTANTS

The constants for SDL::Surface belong to SDL::Video, under the export tag of ':surface'.

SDL_ASYNCBLIT: Use asynchronous blit if possible
SDL_SWSURFACE: Store in system memory
SDL_HWSURFACE: Store in video memory

METHODS

new

 my $surface = SDL::Surface->new(
     $flags, $width, $height, $depth, $Rmask, $Gmask, $Bmask, $Amask
 );

The constructor creates a new surface with the specified parameter values.

The four mask values are the bits that the channel will ignore. For example, an Rmask of 0xFF will ignore that channel completely, making everything on the surface more green/blue.

new_from

 my $surface = SDL::Surface->new_from(
     $surface, $width, $height, $depth, $Rmask, $Gmask, $Bmask, $Amask
 );

The constructor creates a new surface with the specified parameter values. The flags are taken from the specified $surface.

w

 my $w = $surface->w;

Returns the width of the surface. SDL::Surface width is defined at construction so this is read-only.

h

 my $h = $surface->h;

Returns the height of the surface. SDL::Surface height is defined at construction so this is read-only.

format

 my $format = $surface->format;

The format of the pixels stored in the surface. See SDL::PixelFormat

pitch

 my $pitch = $surface->pitch;

The scanline length in bytes.

Direct Write to Surface Pixel

Disclaimer: The following methods can be very slow, making them suitable for creating surfaces, but not for animations

get_pixel

 my $pixel = $surface->get_pixel( $offset )

Returns the numeric pixel value for the given $offset. The pixel value depends on current pixel format.

Note: For surfaces with a palette (1 byte per pixel) the palette index is returned instead of color values.

set_pixels

 $surface->set_pixels( $offset, $value );

Sets the pixel $value to the given $offset. The pixel value must fit the pixel format of the surface.

Note: For surfaces with a palette (1 byte per pixel) the palette index must be passed instead of color values.

Example:

 sub putpixel {
     my ($x, $y, $color) = @_;
     $display->set_pixels( $x + $y * $display->w, $color);
 }

See also examples/pixel_operations/sols/ch02.pl!

get_pixels_ptr

 my $ptr = $surface->get_pixels_ptr;

Returns a reference to the surface's pixels.

AUTHORS

See ``AUTHORS'' in SDL.