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#include <string.h>
#include "common.h"
#include "gba-buttons.c"
#include "background-tiles.c"
#include "sprites.h"
//
// Main functions.
//
// TODO: Cleanup OBJ/OAM memory copying and access.
//
#define CBB_0 0
#define SBB_0 28
#define CROSS_TX 15
#define CROSS_TY 10
u16 *bg0_map = SCREENBLOCK_MEM[SBB_0];
void
init_map() {
// initialize a background
BG_CTRL_0 = BG_CHARBLOCK(CBB_0) | BG_SCREENBLOCK(SBB_0) | BG_SIZE(3);
BG_H_SCROLL_0 = 0;
BG_V_SCROLL_0 = 0;
// (1) create the tiles: basic tile and a cross
const Tile tiles[2] = {
{{0x11111111, 0x01111111, 0x01111111, 0x01111111,
0x01111111, 0x01111111, 0x01111111, 0x00000001}},
{{0x00000000, 0x00100100, 0x01100110, 0x00011000,
0x00011000, 0x01100110, 0x00100100, 0x00000000}},
};
TILE_MEM[CBB_0][0] = tiles[0];
TILE_MEM[CBB_0][1] = tiles[1];
// (2) create a palette
PAL_BANK_BG[0][1] = rgb15(31, 0, 0);
PAL_BANK_BG[1][1] = rgb15( 0, 31, 0);
PAL_BANK_BG[2][1] = rgb15( 0, 0, 31);
PAL_BANK_BG[3][1] = rgb15(16, 16, 16);
// (3) Create a map: four contingent blocks of
// 0x0000, 0x1000, 0x2000, 0x3000.
u16 *pse = bg0_map;
for(int i = 0; i < 4; i++) {
for(int j = 0; j < 32 * 32; j++) {
*pse++ = SCREENBLOCK_ENTRY_PAL(i) | 0;
}
}
}
int main(void) {
init_map();
// Configure the display in mode 0 to show OBJs, where tile memory is
// sequential.
DISP_CTRL = DISP_ENABLE_SPRITES | DISP_MODE_0 | DISP_BG_0;
u32 tx, ty, se_curr, se_prev= CROSS_TY * 32 + CROSS_TX;
bg0_map[se_prev]++; // initial position of cross
// Initialize sprite button overlay.
init_sprite_pal(0, COLOR_WHITE);
init_sprites(0);
init_button_sprites();
int frame_counter = 0;
int x = 0;
int y = 0;
while(true) {
wait_vsync();
poll_keys();
if (key_hold(KEY_DOWN)) {
y += 3;
}
if (key_hold(KEY_UP)) {
y -= 3;
}
if (key_hold(KEY_LEFT)) {
x -= 3;
}
if (key_hold(KEY_RIGHT)) {
x += 3;
}
tx = ((x >> 3) + CROSS_TX) & 0x3F;
ty = ((y >> 3) + CROSS_TY) & 0x3F;
se_curr = se_index(tx, ty, 64);
if(se_curr != se_prev) {
bg0_map[se_prev]--;
bg0_map[se_curr]++;
se_prev= se_curr;
}
frame_counter++;
BG_H_SCROLL_0 = x;
BG_V_SCROLL_0 = y;
update_button_sprites();
};
return 0;
}
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