src/main.c


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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.

int main(void) {
    // Load background palette.
    memcpy(&PAL_BUFFER_BG[0], &bg_palette, 512);
    memcpy(&TILE_MEM[0][0], bg_data, 3168);
    memcpy(&SCREENBLOCK_MEM[30][0], bg_map, 2048);

    // Configure BG0 to use 4bpp, 64x32 tile map in charblock 0 and screenblock
    // 31.
    BG_CTRL_0 = BG_CHARBLOCK(0) | BG_SCREENBLOCK(30) | BG_SIZE(0);
    BG_H_SCROLL_0 = 0;
    BG_V_SCROLL_0 = 0;

    // 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;

    // 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;
        }

        frame_counter++;
        BG_H_SCROLL_0 = x;
        BG_V_SCROLL_0 = y;

        update_button_sprites();
    };

    return 0;
}