Example: objecttext_render

#![no_std]
#![no_main]

use agb::{
    display::{
        object::{ChangeColour, ObjectTextRender, PaletteVram, Size, TextAlignment},
        palette16::Palette16,
        Font, HEIGHT, WIDTH,
    },
    include_font,
    input::Button,
};

extern crate alloc;

use core::fmt::Write;

static FONT: Font = include_font!("examples/font/ark-pixel-10px-proportional-ja.ttf", 10);

#[agb::entry]
fn entry(gba: agb::Gba) -> ! {
    main(gba);
}

fn main(mut gba: agb::Gba) -> ! {
    let (mut unmanaged, _sprites) = gba.display.object.get_unmanaged();

    let mut palette = [0x0; 16];
    palette[1] = 0xFF_FF;
    palette[2] = 0x00_FF;
    let palette = Palette16::new(palette);
    let palette = PaletteVram::new(&palette).unwrap();

    let timer = gba.timers.timers();
    let mut timer: agb::timer::Timer = timer.timer2;

    timer.set_enabled(true);
    timer.set_divider(agb::timer::Divider::Divider256);

    let mut wr = ObjectTextRender::new(&FONT, Size::S16x16, palette);
    let start = timer.value();

    let player_name = "You";
    let _ = writeln!(
            wr,
            "Woah!{change2} {player_name}! {change1}こんにちは! I have a bunch of text I want to show you. However, you will find that the amount of text I can display is limited. Who'd have thought! Good thing that my text system supports scrolling! It only took around 20 jank versions to get here!",
            change2 = ChangeColour::new(2),
            change1 = ChangeColour::new(1),
        );
    let end = timer.value();

    agb::println!(
        "Write took {} cycles",
        256 * (end.wrapping_sub(start) as u32)
    );

    let vblank = agb::interrupt::VBlank::get();
    let mut input = agb::input::ButtonController::new();

    let start = timer.value();

    wr.layout((WIDTH, 40), TextAlignment::Justify, 2);
    let end = timer.value();

    agb::println!(
        "Layout took {} cycles",
        256 * (end.wrapping_sub(start) as u32)
    );

    let mut line_done = false;
    let mut frame = 0;

    loop {
        vblank.wait_for_vblank();
        input.update();
        let oam = &mut unmanaged.iter();
        wr.commit(oam);

        let start = timer.value();
        if frame % 4 == 0 {
            line_done = !wr.next_letter_group();
        }
        if line_done && input.is_just_pressed(Button::A) {
            line_done = false;
            wr.pop_line();
        }
        wr.update((0, HEIGHT - 40));
        let end = timer.value();

        frame += 1;

        agb::println!(
            "Took {} cycles, line done {}",
            256 * (end.wrapping_sub(start) as u32),
            line_done
        );
    }
}