NAME¶
ALLEGRO_LOCKED_REGION - Allegro 5 API
SYNOPSIS¶
-
#include <allegro5/allegro.h>
typedef struct ALLEGRO_LOCKED_REGION ALLEGRO_LOCKED_REGION;
DESCRIPTION¶
Users who wish to manually edit or read from a bitmap are required to lock it
first. The ALLEGRO_LOCKED_REGION structure represents the locked region of the
bitmap. This call will work with any bitmap, including memory bitmaps.
-
typedef struct ALLEGRO_LOCKED_REGION {
void *data;
int format;
int pitch;
int pixel_size;
} ALLEGRO_LOCKED_REGION;
- •
- data points to the leftmost pixel of the first row (row 0) of the
locked region.
- •
- format indicates the pixel format of the data.
- •
- pitch gives the size in bytes of a single row (also known as the
stride). The pitch may be greater than width * pixel_size
due to padding; this is not uncommon. It is also not uncommon for
the pitch to be negative (the bitmap may be upside down).
- •
- pixel_size is the number of bytes used to represent a single
pixel.
SEE ALSO¶
al_lock_bitmap(3alleg5), al_lock_bitmap_region(3alleg5),
al_unlock_bitmap(3alleg5), ALLEGRO_PIXEL_FORMAT(3alleg5)