NAME

SDL2::pixels - Enumerated Pixel Format Definitions

SYNOPSIS

use SDL2 qw[:pixels];

DESCRIPTION

SDL2::pixels defines pixel format values and related functions.

Functions

SDL_GetPixelFormatName( ... )

Get the human readable name of a pixel format.

SDL_GetPixelFormatName(370546692);

Expected parameters include:

format - the pixel format to query

Returns the human readable name of the specified pixel format or SDL_PIXELFORMAT_UNKNOWN if the format isn't recognized.

SDL_PixelFormatEnumToMasks( ... )

Convert one of the enumerated pixel formats to a bpp value and RGBA masks.

SDL_PixelFormatEnumToMasks(
	SDL_PIXELFORMAT_ABGR8888,
	\my $bpp,
	\my $rmask, \my $bmask, \my $gmask, \my $amask
) || return SDL_SetError('Unknown format');

Expected parameters include:

format - one of the SDL_PixelFormatEnum values
bpp - a bits per pixel value; usually 15, 16, or 32
Rmask - a pointer filled in with the red mask for the format
Gmask - a pointer filled in with the green mask for the format
Bmask - a pointer filled in with the blue mask for the format
Amask - a pointer filled in with the alpha mask for the format

Returns SDL_TRUE on success or SDL_FALSE if the conversion wasn't possible; call SDL_GetError( ) for more information.

SDL_MasksToPixelFormatEnum( ... )

Convert a bpp value and RGBA masks to an enumerated pixel format.

# ARGB8888
my $amask = 0xff000000;
my $rmask = 0x00ff0000;
my $gmask = 0x0000ff00;
my $bmask = 0x000000ff;
SDL_MasksToPixelFormatEnum( 32, $rmask, $gmask, $bmask, $amask );

This will return SDL_PIXELFORMAT_UNKNOWN if the conversion wasn't possible.

Expected parameters include:

bpp - a bits per pixel value; usually 15, 16, or 32
Rmask - the red mask for the format
Gmask - the green mask for the format
Bmask - the blue mask for the format
Amask - the alpha mask for the format

Returns one of the SDL_PixelFormatEnum values.

SDL_AllocFormat( ... )

Create an SDL2::PixelFormat structure corresponding to a pixel format.

# ARGB8888
my $amask = 0xff000000;
my $rmask = 0x00ff0000;
my $gmask = 0x0000ff00;
my $bmask = 0x000000ff;
my $format
    = SDL_AllocFormat( SDL_MasksToPixelFormatEnum( 32, $rmask, $gmask, $bmask, $amask ) );

Returned structure may come from a shared global cache (i.e. not newly allocated), and hence should not be modified, especially the palette. Weird errors such as Blit combination not supported may occur.

Expected parameters include:

pixel_format - one of the SDL_PixelFormatEnum values

Returns the new SDL2::PixelFormat structure or undef on failure; call SDL_GetError( ) for more information.

SDL_FreeFormat( ... )

Free an SDL_PixelFormat structure allocated by SDL_AllocFormat( ... ).

Expected parameters include:

format the SDL2::PixelFormat structure to free

SDL_AllocPalette( ... )

Create a palette structure with the specified number of color entries.

my $palette = SDL_AllocPalette(256);

The palette entries are initialized to white.

Expected parameters include:

ncolors - represents the number of color entries in the color palette

Returns a new SDL2::Palette structure on success or undef on failure (e.g. if there wasn't enough memory); call SDL_GetError( ) for more information.

SDL_SetPixelFormatPalette( ... )

Set the palette for a pixel format structure.

Expected parameters include:

format - the SDL2::PixelFormat structure that will use the palette
palette - the SDL2::Palette structure that will be used

Returns 0 on success or a negative error code on failure; call SDL_GetError( ) for more information.

SDL_SetPaletteColors( ... )

Set a range of colors in a palette.

Expected parameters include:

palette - the SDL_Palette structure to modify
colors - an array of SDL_Color structures to copy into the palette
firstcolor - the index of the first palette entry to modify
ncolors - the number of entries to modify

Returns 0 on success or a negative error code if not all of the colors could be set; call SDL_GetError( ) for more information.

SDL_FreePalette( ... )

Free a palette created with SDL_AllocPalette( ... ).

Expected parameters include:

palette - the SDL2::Palette structure to be freed

SDL_MapRGB( ... )

Map an RGB triple to an opaque pixel value for a given pixel format.

This function maps the RGB color value to the specified pixel format and returns the pixel value best approximating the given RGB color value for the given pixel format.

If the format has a palette (8-bit) the index of the closest matching color in the palette will be returned.

If the specified pixel format has an alpha component it will be returned as all 1 bits (fully opaque).

If the pixel format bpp (color depth) is less than 32-bpp then the unused upper bits of the return value can safely be ignored (e.g., with a 16-bpp format the return value can be assigned to a Uint16, and similarly a Uint8 for an 8-bpp format).

Expected parameters include:

format - an SDL2::PixelFormat structure describing the pixel format
r - the red component of the pixel in the range 0-255
g - the green component of the pixel in the range 0-255
b - the blue component of the pixel in the range 0-255

Returns a pixel value.

SDL_MapRGBA( ... )

Map an RGBA quadruple to a pixel value for a given pixel format.

This function maps the RGBA color value to the specified pixel format and returns the pixel value best approximating the given RGBA color value for the given pixel format.

If the specified pixel format has no alpha component the alpha value will be ignored (as it will be in formats with a palette).

If the format has a palette (8-bit) the index of the closest matching color in the palette will be returned.

If the pixel format bpp (color depth) is less than 32-bpp then the unused upper bits of the return value can safely be ignored (e.g., with a 16-bpp format the return value can be assigned to a Uint16, and similarly a Uint8 for an 8-bpp format).

Expected parameters include:

format - an SDL2::PixelFormat structure describing the format of the pixel
r - the red component of the pixel in the range 0-255
g - the green component of the pixel in the range 0-255
b - the blue component of the pixel in the range 0-255
a - the alpha component of the pixel in the range 0-255

Returns a pixel value.

SDL_GetRGB( ... )

Get RGB values from a pixel in the specified format.

This function uses the entire 8-bit [0..255] range when converting color components from pixel formats with less than 8-bits per RGB component (e.g., a completely white pixel in 16-bit RGB565 format would return [0xff, 0xff, 0xff] not [0xf8, 0xfc, 0xf8]).

Expected parameters include:

pixel a pixel value
format an SDL2::PixelFormat structure describing the format of the pixel
r - a pointer filled in with the red component
g - a pointer filled in with the green component
b - a pointer filled in with the blue component

SDL_GetRGBA( ... )

Get RGBA values from a pixel in the specified format.

This function uses the entire 8-bit [0..255] range when converting color components from pixel formats with less than 8-bits per RGB component (e.g., a completely white pixel in 16-bit RGB565 format would return [0xff, 0xff, 0xff] not [0xf8, 0xfc, 0xf8]).

If the surface has no alpha component, the alpha will be returned as 0xff (100% opaque).

Expected parameters include:

pixel - a pixel value
format - an SDL2::PixelFormat structure describing the format of the pixel
r - a pointer filled in with the red component
g - a pointer filled in with the green component
b - a pointer filled in with the blue component
a - a pointer filled in with the alpha component

SDL_CalculateGammaRamp( ... )

Calculate a 256 entry gamma ramp for a gamma value.

my @ramp = (0) x 256; # preallocate to avoid spurious warnings
SDL_CalculateGammaRamp( .925, \@ramp ); # \@ramp will be filled

Expected parameters include:

gamma - a gamma value where 0.0 is black and 1.0 is identity
ramp - an array of 256 values filled in with the gamma ramp

Transparency definitions

These define alpha as the opacity of a surface.

SDL_ALPHA_OPAQUE
SDL_ALPHA_TRANSPARENT

SDL_PixelType

These may be imported with the tag :pixelType

SDL_PIXELTYPE_UNKNOWN
SDL_PIXELTYPE_INDEX1
SDL_PIXELTYPE_INDEX4
SDL_PIXELTYPE_INDEX8
SDL_PIXELTYPE_PACKED8
SDL_PIXELTYPE_PACKED16
SDL_PIXELTYPE_PACKED32
SDL_PIXELTYPE_ARRAYU8
SDL_PIXELTYPE_ARRAYU16
SDL_PIXELTYPE_ARRAYU32
SDL_PIXELTYPE_ARRAYF16
SDL_PIXELTYPE_ARRAYF32

SDL_BitmapOrder

Bitmap pixel order, high bit -> low bit. These maybe imported with the :bitmapOrder tag.

SDL_BITMAPORDER_NONE
SDL_BITMAPORDER_4321
SDL_BITMAPORDER_1234

SDL_PackedOrder

Packed component order, high bit -> low bit. These may be imported with the :packedOrder tag.

SDL_PACKEDORDER_NONE
SDL_PACKEDORDER_XRGB
SDL_PACKEDORDER_RGBX
SDL_PACKEDORDER_ARGB
SDL_PACKEDORDER_RGBA
SDL_PACKEDORDER_XBGR
SDL_PACKEDORDER_BGRX
SDL_PACKEDORDER_ABGR
SDL_PACKEDORDER_BGRA

SDL_ArrayOrder

Array component order, low byte -> high byte. These may be imported with the :arrayOrder tag.

SDL_ARRAYORDER_NONE
SDL_ARRAYORDER_RGB
SDL_ARRAYORDER_RGBA
SDL_ARRAYORDER_ARGB
SDL_ARRAYORDER_BGR
SDL_ARRAYORDER_BGRA
SDL_ARRAYORDER_ABGR

SDL_PackedLayout

Packed component layout. These values may be imported with the :packedLayout tag.

SDL_PACKEDLAYOUT_NONE
SDL_PACKEDLAYOUT_332
SDL_PACKEDLAYOUT_4444
SDL_PACKEDLAYOUT_1555
SDL_PACKEDLAYOUT_5551
SDL_PACKEDLAYOUT_565
SDL_PACKEDLAYOUT_8888
SDL_PACKEDLAYOUT_2101010
SDL_PACKEDLAYOUT_1010102

:pixels

These utility functions may be imported with the :pixels tag.

SDL_DEFINE_PIXELFOURCC( ... )
SDL_DEFINE_PIXELFORMAT( ... )
SDL_PIXELFLAG( ... )
SDL_PIXELTYPE( ... )
SDL_PIXELORDER( ... )
SDL_PIXELLAYOUT( ... )
SDL_BITSPERPIXEL( ... )
SDL_BYTESPERPIXEL( ... )
SDL_ISPIXELFORMAT_INDEXED( ... )
SDL_ISPIXELFORMAT_PACKED( ... )
SDL_ISPIXELFORMAT_ARRAY( ... )
SDL_ISPIXELFORMAT_ALPHA( ... )
SDL_ISPIXELFORMAT_FOURCC( ... )

SDL_PixelFormatEnum

These values may be imported with the :pixelFormatEnum tag.

SDL_PIXELFORMAT_UNKNOWN
SDL_PIXELFORMAT_INDEX1LSB
SDL_PIXELFORMAT_INDEX1MSB
SDL_PIXELFORMAT_INDEX4LSB
SDL_PIXELFORMAT_INDEX4MSB
SDL_PIXELFORMAT_INDEX8
SDL_PIXELFORMAT_RGB332
SDL_PIXELFORMAT_XRGB4444
SDL_PIXELFORMAT_RGB444
SDL_PIXELFORMAT_XBGR4444
SDL_PIXELFORMAT_BGR444
SDL_PIXELFORMAT_XRGB1555
SDL_PIXELFORMAT_RGB555
SDL_PIXELFORMAT_XBGR1555
SDL_PIXELFORMAT_BGR555
SDL_PIXELFORMAT_ARGB4444
SDL_PIXELFORMAT_RGBA4444
SDL_PIXELFORMAT_ABGR4444
SDL_PIXELFORMAT_BGRA4444
SDL_PIXELFORMAT_ARGB1555
SDL_PIXELFORMAT_RGBA5551
SDL_PIXELFORMAT_ABGR1555
SDL_PIXELFORMAT_BGRA5551
SDL_PIXELFORMAT_RGB565
SDL_PIXELFORMAT_BGR565
SDL_PIXELFORMAT_RGB24
SDL_PIXELFORMAT_BGR24
SDL_PIXELFORMAT_XRGB8888
SDL_PIXELFORMAT_RGB888
SDL_PIXELFORMAT_RGBX8888
SDL_PIXELFORMAT_XBGR8888
SDL_PIXELFORMAT_BGR888
SDL_PIXELFORMAT_BGRX8888
SDL_PIXELFORMAT_ARGB8888
SDL_PIXELFORMAT_RGBA8888
SDL_PIXELFORMAT_ABGR8888
SDL_PIXELFORMAT_BGRA8888
SDL_PIXELFORMAT_ARGB2101010
SDL_PIXELFORMAT_RGBA32
SDL_PIXELFORMAT_ARGB32
SDL_PIXELFORMAT_BGRA32
SDL_PIXELFORMAT_ABGR32
SDL_PIXELFORMAT_YV12 - Planar mode: Y + V + U (3 planes)
SDL_PIXELFORMAT_IYUV - Planar mode: Y + U + V (3 planes)
SDL_PIXELFORMAT_YUY2 - Packed mode: Y0+U0+Y1+V0 (1 plane)
SDL_PIXELFORMAT_UYVY - Packed mode: U0+Y0+V0+Y1 (1 plane)
SDL_PIXELFORMAT_YVYU - Packed mode: Y0+V0+Y1+U0 (1 plane)
SDL_PIXELFORMAT_NV12 - Planar mode: Y + U/V interleaved (2 planes)
SDL_PIXELFORMAT_NV21 - Planar mode: Y + V/U interleaved (2 planes)
SDL_PIXELFORMAT_EXTERNAL_OES - Android video texture format

LICENSE

Copyright (C) Sanko Robinson.

This library is free software; you can redistribute it and/or modify it under the terms found in the Artistic License 2. Other copyrights, terms, and conditions may apply to data transmitted through this module.

AUTHOR

Sanko Robinson <sanko@cpan.org>