void hide_bkg(); // Disable background
Calling hide_bkg(); turns all the background tiles off. The sprites are still visible.
This command does not work with no$gmb.
void show_bkg(); // Enable Background
Calling show_bkg()/SHOW_BKG; turns all the background tiles. This is used to turn them on
after using the hide_bkg();
* Note : On the Gameboy Color, the background tiles start automatically, however, on the
gameboy and gameboy pocket, they initially start off, so call a SHOW_BKG; after you load
your background data.
void scroll_bkg(int x, int y); // Scroll background x/y >=0 <=255
void set_bkg_data(int first_tile, int nb_tiles, unsigned char *data);
/* -128 <= first_tile <= 127 * -128 <= first_tile+nb_tiles <= 127 * nb_tiles
>= 1 */
set_bkg_data is used to load the background tiles and palette information into memory.
first_tile is the first tile that you want to load data into, usually 0. nb_tiles is the
number of tiles you want to load into memory. *data is a pointer to the unsigned char that
the tiles are stored in.
void set_bkg_tiles(int x, int y, int w, int h, unsigned char *tilelist);
/* 0 <= x <= 31 * 0 <= y <= 31 * 1 <= w <= 32-x * 1 <= h <= 32-y
*/
set_bkg_tiles puts the tile data onto the screen. You must load the tiles into memory
using set_bkg_data first. x is the starting location in tiles (pixels / 8) to load the
data into. y is the starting location in tiles (pixels / 8) to load the data into. w is
the width of the data you want to load in tiles. h is the height in tiles of the data you
want to put on the screen. *tilelist is a pointer to an unsigned char that has a tile map
of what you want to be displayed.