HonkBird / src / main.rs

// Games made using `agb` are no_std which means you don't have access to the standard
// rust library. This is because the game boy advance doesn't have an operating
// system, so most of the content of the standard library doesn't apply.
#![no_std]
// `agb` defines its own `main` function, so you must declare your game's main function
// using the #[agb::entry] proc macro. Failing to do so will cause failure in linking
// which won't be a particularly clear error message.
#![no_main]
// This is required to allow writing tests
#![cfg_attr(test, feature(custom_test_frameworks))]
#![cfg_attr(test, reexport_test_harness_main = "test_main")]
#![cfg_attr(test, test_runner(agb::test_runner::test_runner))]

mod game;

// By default no_std crates don't get alloc, so you won't be able to use things like Vec
// until you declare the extern crate. `agb` provides an allocator so it will all work
extern crate alloc;

use crate::game::{GameLoop, GameState};
use agb::display::font::{AlignmentKind, Font, Layout, RegularBackgroundTextRenderer};
use agb::display::tiled::{RegularBackground, RegularBackgroundSize, TileFormat, VRAM_MANAGER};
use agb::display::{Priority, Rgb15};
use agb::fixnum::Num;
use agb::input::Button;
use agb::{include_aseprite, include_font};

include_aseprite!(
    mod goose_sprites,
    "gfx/flap_animated.aseprite"
);

static FONT: Font = include_font!("fnt/Born2bSportyV2.ttf", 24);

type Fixed = Num<i32, 8>;

#[agb::entry]
fn main(mut gba: agb::Gba) -> ! {
    let mut game = GameLoop::new();
    VRAM_MANAGER.set_background_palette_colour(0, 1, Rgb15::WHITE);

    let mut bg = RegularBackground::new(
        Priority::P0,
        RegularBackgroundSize::Background32x32,
        TileFormat::FourBpp,
    );

    let mut text_layout = Layout::new(
        "HonkBird\nPress Start to play",
        &FONT,
        AlignmentKind::Left,
        32,
        200,
    );

    let mut text_renderer = RegularBackgroundTextRenderer::new((4, 50));
    let mut button_controller = agb::input::ButtonController::new();
    loop {
        match game.game_state {
            GameState::Start => {
                button_controller.update();

                if let Some(letter) = text_layout.next() {
                    text_renderer.show(&mut bg, &letter);
                }
                if button_controller.is_just_pressed(Button::START) {
                    game.game_state = GameState::Playing;
                }
                let mut gfx = gba.graphics.get();
                let mut frame = gfx.frame();

                bg.show(&mut frame);

                frame.commit();
            }
            GameState::Playing => {
                game.run(&mut gba);
            }
            GameState::GameOver => {}
        }
    }
}