Pixel Definition

Collaboration diagram for Pixel Definition:

Macros
#define	BJ_PIXEL_TYPE_INDEX   0x01
#define	BJ_PIXEL_TYPE_BITFIELD   0x02
#define	BJ_PIXEL_TYPE_BYTES   0x03
#define	BJ_PIXEL_ORDER_RGB   0x01
#define	BJ_PIXEL_ORDER_XRGB   BJ_PIXEL_ORDER_RGB
#define	BJ_PIXEL_ORDER_BGR   0x02
#define	BJ_PIXEL_ORDER_XBGR   BJ_PIXEL_ORDER_BGR
#define	BJ_PIXEL_ORDER_RGBX   0x03
#define	BJ_PIXEL_ORDER_BGRX   0x04
#define	BJ_PIXEL_ORDER_ARGB   0x05
#define	BJ_PIXEL_ORDER_ABGR   0x06
#define	BJ_PIXEL_ORDER_RGBA   0x07
#define	BJ_PIXEL_ORDER_BGRA   0x08
#define	BJ_PIXEL_LAYOUT_1555   0x00
#define	BJ_PIXEL_LAYOUT_8888   0x01
#define	BJ_PIXEL_LAYOUT_565   0x02
#define	BJ_PIXEL_MODE_MAKE(bpp, type, layout, order)
#define	BJ_PIXEL_MODE_MAKE_INDEXED(bpp)
#define	BJ_PIXEL_MODE_MAKE_BITFIELD_16(layout, order)
#define	BJ_PIXEL_MODE_MAKE_BITFIELD_32(layout, order)
#define	BJ_PIXEL_MODE_MAKE_BYTES(bpp, order)
#define	BJ_PIXEL_GET_BPP(fmt)
#define	BJ_PIXEL_GET_TYPE(fmt)
#define	BJ_PIXEL_GET_LAYOUT(fmt)
#define	BJ_PIXEL_GET_ORDER(fmt)

Enumerations
enum	bj_pixel_mode {   BJ_PIXEL_MODE_UNKNOWN = 0x00u , BJ_PIXEL_MODE_INDEXED_1 = 0x00000101u , BJ_PIXEL_MODE_INDEXED_4 = 0x00000104u , BJ_PIXEL_MODE_INDEXED_8 = 0x00000108u ,   BJ_PIXEL_MODE_XRGB1555 = 0x01000210u , BJ_PIXEL_MODE_RGB565 = 0x01020210u , BJ_PIXEL_MODE_XRGB8888 = 0x01010220u , BJ_PIXEL_MODE_BGR24 = 0x02000318u }

Functions
void	bj_make_pixel_rgb (bj_pixel_mode mode, uint32_t value, uint8_t *p_red, uint8_t *p_green, uint8_t *p_blue)
uint32_t	bj_get_pixel_value (bj_pixel_mode mode, uint8_t red, uint8_t green, uint8_t blue)
int	bj_compute_pixel_mode (uint8_t bpp, uint32_t red_mask, uint32_t green_mask, uint32_t blue_mask)
size_t	bj_compute_bitmap_stride (size_t width, bj_pixel_mode mode)

Detailed Description

Macro Definition Documentation

BJ_PIXEL_GET_BPP

#define BJ_PIXEL_GET_BPP

(

fmt

)

Value:

((fmt) & 0xFF)

Extracts the bits-per-pixel from a pixel format.

Parameters

fmt	Pixel format value.

BJ_PIXEL_GET_LAYOUT

#define BJ_PIXEL_GET_LAYOUT

(

fmt

)

Value:

(((fmt) >> 16) & 0xFF)

Extracts the pixel layout from a pixel format.

Parameters

fmt	Pixel format value.

BJ_PIXEL_GET_ORDER

#define BJ_PIXEL_GET_ORDER

(

fmt

)

Value:

(((fmt) >> 24) & 0xFF)

Extracts the pixel order from a pixel format.

Parameters

fmt	Pixel format value.

BJ_PIXEL_GET_TYPE

#define BJ_PIXEL_GET_TYPE

(

fmt

)

Value:

(((fmt) >> 8) & 0xFF)

Extracts the pixel type from a pixel format.

Parameters

fmt	Pixel format value.

BJ_PIXEL_LAYOUT_1555

#define BJ_PIXEL_LAYOUT_1555   0x00

Pixel layout: 16-bit with 1-bit alpha, 5-bit red, green, and blue (1555).

BJ_PIXEL_LAYOUT_565

#define BJ_PIXEL_LAYOUT_565   0x02

Pixel layout: 16-bit with 5 bits for red and blue, 6 bits for green (565).

BJ_PIXEL_LAYOUT_8888

#define BJ_PIXEL_LAYOUT_8888   0x01

Pixel layout: 32-bit with 8 bits per channel (8888).

BJ_PIXEL_MODE_MAKE

#define BJ_PIXEL_MODE_MAKE	(		bpp,
			type,
			layout,
			order )

Value:

(((order & 0xFF) << 24) | ((layout & 0xFF) << 16) | ((type & 0xFF) << 8) | (bpp & 0xFF))

Creates a pixel format mode from bits-per-pixel, type, layout, and order.

Parameters

bpp	Bits-per-pixel.
type	Pixel type (e.g., indexed, bitfield, or bytes).
layout	Pixel layout (e.g., 1555, 8888, or 565).
order	Pixel order (e.g., RGB, ARGB, etc.).

BJ_PIXEL_MODE_MAKE_BITFIELD_16

#define BJ_PIXEL_MODE_MAKE_BITFIELD_16	(		layout,
			order )

Value:

BJ_PIXEL_MODE_MAKE(16, BJ_PIXEL_TYPE_BITFIELD, layout, order)

Creates a 16-bit bitfield pixel format.

Parameters

layout	Pixel layout (e.g., 1555, 565).
order	Pixel order (e.g., RGB, ARGB).

BJ_PIXEL_MODE_MAKE_BITFIELD_32

#define BJ_PIXEL_MODE_MAKE_BITFIELD_32	(		layout,
			order )

Value:

BJ_PIXEL_MODE_MAKE(32, BJ_PIXEL_TYPE_BITFIELD, layout, order)

Creates a 32-bit bitfield pixel format.

Parameters

layout	Pixel layout (e.g., 8888).
order	Pixel order (e.g., RGB, ARGB).

BJ_PIXEL_MODE_MAKE_BYTES

#define BJ_PIXEL_MODE_MAKE_BYTES	(		bpp,
			order )

Value:

BJ_PIXEL_MODE_MAKE(bpp, BJ_PIXEL_TYPE_BYTES, 0, order)

Creates a byte-packed pixel format.

Parameters

bpp	Bits-per-pixel.
order	Pixel order (e.g., RGB, ARGB).

BJ_PIXEL_MODE_MAKE_INDEXED

#define BJ_PIXEL_MODE_MAKE_INDEXED

(

bpp

)

Value:

BJ_PIXEL_MODE_MAKE(bpp, BJ_PIXEL_TYPE_INDEX, 0, 0)

Creates a pixel format for indexed (palette-based) pixels.

Parameters

bpp	Bits-per-pixel.

BJ_PIXEL_ORDER_ABGR

#define BJ_PIXEL_ORDER_ABGR   0x06

Pixel order: Alpha-Blue-Green-Red (ABGR).

BJ_PIXEL_ORDER_ARGB

#define BJ_PIXEL_ORDER_ARGB   0x05

Pixel order: Alpha-Red-Green-Blue (ARGB).

BJ_PIXEL_ORDER_BGR

#define BJ_PIXEL_ORDER_BGR   0x02

Pixel order: Blue-Green-Red (BGR).

BJ_PIXEL_ORDER_BGRA

#define BJ_PIXEL_ORDER_BGRA   0x08

Pixel order: Blue-Green-Red-Alpha (BGRA).

BJ_PIXEL_ORDER_BGRX

#define BJ_PIXEL_ORDER_BGRX   0x04

Pixel order: Blue-Green-Red with padding byte (BGRX).

BJ_PIXEL_ORDER_RGB

#define BJ_PIXEL_ORDER_RGB   0x01

Pixel order: Red-Green-Blue (RGB).

BJ_PIXEL_ORDER_RGBA

#define BJ_PIXEL_ORDER_RGBA   0x07

Pixel order: Red-Green-Blue-Alpha (RGBA).

BJ_PIXEL_ORDER_RGBX

#define BJ_PIXEL_ORDER_RGBX   0x03

Pixel order: Red-Green-Blue with padding byte (RGBX).

BJ_PIXEL_ORDER_XBGR

#define BJ_PIXEL_ORDER_XBGR   BJ_PIXEL_ORDER_BGR

Pixel order: Same as BJ_PIXEL_ORDER_BGR with unused alpha.

BJ_PIXEL_ORDER_XRGB

#define BJ_PIXEL_ORDER_XRGB   BJ_PIXEL_ORDER_RGB

Pixel order: Same as BJ_PIXEL_ORDER_RGB with unused alpha.

BJ_PIXEL_TYPE_BITFIELD

#define BJ_PIXEL_TYPE_BITFIELD   0x02

Pixel type: Bitfield representation (e.g., RGB565).

BJ_PIXEL_TYPE_BYTES

#define BJ_PIXEL_TYPE_BYTES   0x03

Pixel type: Byte-packed representation (e.g., RGBA8888).

BJ_PIXEL_TYPE_INDEX

#define BJ_PIXEL_TYPE_INDEX   0x01

Pixel type: Indexed (palette-based).

Enumeration Type Documentation

bj_pixel_mode

enum bj_pixel_mode

Representation of a pixel encoding.

Enumerator
BJ_PIXEL_MODE_UNKNOWN	Unknown/Invalid pixel mode.
BJ_PIXEL_MODE_INDEXED_1	1bpp indexed
BJ_PIXEL_MODE_INDEXED_4	4bpp indexed
BJ_PIXEL_MODE_INDEXED_8	8bpp indexed
BJ_PIXEL_MODE_XRGB1555	16bpp 555-RGB
BJ_PIXEL_MODE_RGB565	16bpp 565-RGB
BJ_PIXEL_MODE_XRGB8888	32bpp RGB
BJ_PIXEL_MODE_BGR24	24bpp BGR

Function Documentation

bj_compute_bitmap_stride()

size_t bj_compute_bitmap_stride	(	size_t	width,
		bj_pixel_mode	mode )

Returns the stride used for encoding a bitmaps in Banjo.

In a bitmap, the stride is the actual number of bytes used to encode a single row of pixels. Hence, the total size needed for a bitmap of width x height encoded with mode is equal to bj_compute_bitmap_stride(width, mode) * height.

Banjo uses the bits-per-pixel information from mode to compute the stride and aligns the byte count to 4.

Parameters

width	The width in pixel of a row
mode	The pixel mode

Returns

The bitmap stride in bytes

bj_compute_pixel_mode()

int bj_compute_pixel_mode	(	uint8_t	bpp,
		uint32_t	red_mask,
		uint32_t	green_mask,
		uint32_t	blue_mask )

Determine the most suitable bj_pixel_mode from a set of masks.

This function can be used to retrieve what Banjo consider as the pixel mode corresponding to a given depth and masks.

If not suitable pixel mode is found, BJ_PIXEL_MODE_UNKNOWN is returned.

Parameters

bpp	The number of bits used to encode a pixel.
red_mask	A bitmask for the red channel information in the bits.
green_mask	A bitmask for the green channel information in the bits.
blue_mask	A bitmask for the blue channel information in the bits.

Returns

A bj_pixel_mode value.

bj_get_pixel_value()

uint32_t bj_get_pixel_value	(	bj_pixel_mode	mode,
		uint8_t	red,
		uint8_t	green,
		uint8_t	blue )

Returns an opaque value representing a pixel color, given its RGB composition.

Parameters

mode	The pixel mode
red	The red component of the color
green	The green component of the color
blue	The blue component of the color

Returns

An opaque uint32_t value.

bj_make_pixel_rgb()

void bj_make_pixel_rgb	(	bj_pixel_mode	mode,
		uint32_t	value,
		uint8_t *	p_red,
		uint8_t *	p_green,
		uint8_t *	p_blue )

Gets the RGB value of a pixel given its 32-bits representation.

Parameters

mode	The pixel mode
value	The opaque pixel value
p_red	A location to the red component
p_green	A location to the green component
p_blue	A location to the blue component