Pixmap

Data Structures
struct	gp_pixmap
	A pixmap buffer. More...

Macros
#define	GP_PIXEL_IS_CLIPPED(pixmap, x, y)
	Returns true when pixel is clipped out of pixmap.

Functions
gp_pixmap *	gp_pixmap_alloc_ex (gp_size w, gp_size h, gp_pixel_type type, uint32_t stride)
	Allocates a pixmap.
static gp_pixmap *	gp_pixmap_alloc (gp_size w, gp_size h, gp_pixel_type type)
	Allocates a pixmap.
int	gp_pixmap_correction_set (gp_pixmap *self, gp_correction_desc *corr_desc)
	Sets a correction for the pixmap.
static int	gp_pixmap_gamma_set (gp_pixmap *self, float gamma)
	Sets a gamma correction for the pixmap.
static int	gp_pixmap_srgb_set (gp_pixmap *self)
	Sets a sRGB correction for the pixmap.
void	gp_pixmap_free (gp_pixmap *self)
	Frees a pixmap.
static gp_pixmap *	gp_pixmap_from_data (gp_size w, gp_size h, gp_pixel_type type, void *pixels, enum gp_pixmap_init_flags flags)
	Creates a pixmap from a buffer allocated by malloc().

Detailed Description

Function Documentation

gp_pixmap_alloc()

static gp_pixmap * gp_pixmap_alloc ( gp_size w, gp_size h, gp_pixel_type type )

inlinestatic

Allocates a pixmap.

The pixmap consists of two parts, the gp_pixmap structure and pixels array.

The rotation flags are set to (0, 0, 0).

Parameters

w	A pixmap width.
h	A pixmap height.
type	A pixel type.

Returns

A newly allocated pixmap or NULL in a case of malloc() failure.

Definition at line 164 of file gp_pixmap.h.

References gp_pixmap_alloc_ex().

gp_pixmap_alloc_ex()

gp_pixmap * gp_pixmap_alloc_ex	(	gp_size	w,
		gp_size	h,
		gp_pixel_type	type,
		uint32_t	stride )

Allocates a pixmap.

This is a variant of gp_pixmap_alloc() that allows to set a custom image stride. If zero is passed this call is equivalent to gp_pixmap_alloc() and stride is calculated internally.

Parameters

w	A pixmap width.
h	A pixmap height.
type	A pixel type.
stride	The length in bytes of an image buffer row. Must be larger or equal than pixel size in bytes multiplied by width.

Returns

A newly allocated pixmap or NULL in a case of malloc() failure.

Referenced by gp_pixmap_alloc().

gp_pixmap_correction_set()

int gp_pixmap_correction_set	(	gp_pixmap *	self,
		gp_correction_desc *	corr_desc )

Sets a correction for the pixmap.

If there was a gamma correction allready set for the pixmap the original correction reference counters are decremented and the correction is replaced with a new table.

Parameters

self	A pixmap.
corr_desc	A correction description.

Returns

Zero on success. May fail if underlying malloc() has failed.

Referenced by gp_pixmap_gamma_set(), and gp_pixmap_srgb_set().

gp_pixmap_free()

void gp_pixmap_free

(

gp_pixmap *

self

)

Frees a pixmap.

If pixmap->free_pixels is set also free pixel data, this flag is set automatically by gp_pixmap_alloc().

Parameters

self	A pixmap to free.

gp_pixmap_from_data()

static gp_pixmap * gp_pixmap_from_data ( gp_size w, gp_size h, gp_pixel_type type, void * pixels, enum gp_pixmap_init_flags flags )

inlinestatic

Creates a pixmap from a buffer allocated by malloc().

This is actually shorthand for allocating the gp_pixmap structure and calling gp_pixmap_init() on the resulting pointer.

Attention

The user has to make sure that the pixels array has correct size and format.

Parameters

w	Pixmap width
h	Pixmap height
type	A pixel type, describes how pixels are organized in the data buffer.
pixels	A pointer to a buffer with the pixel data.
flags	A bitmask or of the enum gp_pixmap_init_flags

Returns

A newly allocated and initialized pixmap or NULL in a case of a failure.

Definition at line 325 of file gp_pixmap.h.

References gp_pixmap_init().

gp_pixmap_gamma_set()

static int gp_pixmap_gamma_set ( gp_pixmap * self, float gamma )

inlinestatic

Sets a gamma correction for the pixmap.

This is a shorthand for:

gp_correction_desc desc = {
        .corr_type = GP_CORRECTION_TYPE_GAMMA,
        .gamma = gamma;
};
 
gp_pixmap_correction_set(self, &desc);

Parameters

self	A pixmap.
gamma	A gamma value.

Returns

Zero on success. May fail if underlying malloc() has failed.

Definition at line 203 of file gp_pixmap.h.

References GP_CORRECTION_TYPE_GAMMA, and gp_pixmap_correction_set().

gp_pixmap_srgb_set()

static int gp_pixmap_srgb_set ( gp_pixmap * self )

inlinestatic

Sets a sRGB correction for the pixmap.

This is a shorthand for:

gp_correction_desc desc = {
        .corr_type = GP_CORRECTION_TYPE_SRGB,
};
 
gp_pixmap_correction_set(self, &desc);

Parameters

self

A pixmap.

Returns

Zero on success. May fail if underlying malloc() has failed.

Definition at line 230 of file gp_pixmap.h.

References GP_CORRECTION_TYPE_SRGB, and gp_pixmap_correction_set().