Animerade fiender

Screenshot

Nu är det bara fienderna som behöver bytas från tråkiga fyrkanter till lite mer spännande grafik. Det här fungerar likadant som med skeppet, vi laddar in en textur, skapar en animeringssprite och byter hur fienderna ritas ut.

Bug

I version 0.4.4 av Macroquad är det en bugg som gör att texturerna inte fungerar som de ska när build_textures_atlas används. Om texturerna ser konstiga ut eller flimrar så prova att ta bort detta anrop.

Implementering

Ladda in textur

Ladda in texturen enemy-small.png och sätt filter mode till Nearest.

    let enemy_small_texture: Texture2D = load_texture("enemy-small.png")
        .await
        .expect("Couldn't load file");
    enemy_small_texture.set_filter(FilterMode::Nearest);
    build_textures_atlas();

Skapa animering

Spritesheet för rymdskeppet

Skapa en AnimatedSprite som beskriver vilka animationer som finns i texturen. Det är bara en animering med två bildrutor. Grafiken för fienden är 16x16 bildrutor, men texturen har en pixels mellanrum mellan bildrutorna för att inte orsaka blödning mellan rutorna när vi skalar texturen.

    let mut enemy_small_sprite = AnimatedSprite::new(
        17,
        16,
        &[Animation {
            name: "enemy_small".to_string(),
            row: 0,
            frames: 2,
            fps: 12,
        }],
        true,
    );

Uppdatera animering

Även fiendens sprite måste uppdateras efter animeringarna för rymdskeppet och kulorna.

                ship_sprite.update();
                bullet_sprite.update();
                enemy_small_sprite.update();

Rita bildrutor för fiender

Nu kan vi byta ut utritningen av fyrkanter till att rita ut texturen från animeringen. Vi hämtar ut bildrutan från enemy_frame och använder dess source_rect i DrawTextureParams. Eftersom fienderna har slumpad storlek så utgår vi från fiendens storlek när vi sätter dest_size och X- och Y-koordinater.

                let enemy_frame = enemy_small_sprite.frame();
                for square in &squares {
                    draw_texture_ex(
                        &enemy_small_texture,
                        square.x - square.size / 2.0,
                        square.y - square.size / 2.0,
                        WHITE,
                        DrawTextureParams {
                            dest_size: Some(vec2(square.size, square.size)),
                            source: Some(enemy_frame.source_rect),
                            ..Default::default()
                        },
                    );
                }

Nu har vi bytt till grafik för alla element i spelet och det ser mer ut som ett riktigt spel.

Kompletta källkoden

Klicka för att visa hela källkoden
use macroquad::experimental::animation::{AnimatedSprite, Animation};
use macroquad::prelude::*;
use macroquad_particles::{self as particles, AtlasConfig, Emitter, EmitterConfig};

use std::fs;

const FRAGMENT_SHADER: &str = include_str!("starfield-shader.glsl");

const VERTEX_SHADER: &str = "#version 100
attribute vec3 position;
attribute vec2 texcoord;
attribute vec4 color0;
varying float iTime;

uniform mat4 Model;
uniform mat4 Projection;
uniform vec4 _Time;

void main() {
    gl_Position = Projection * Model * vec4(position, 1);
    iTime = _Time.x;
}
";

struct Shape {
    size: f32,
    speed: f32,
    x: f32,
    y: f32,
    collided: bool,
}

impl Shape {
    fn collides_with(&self, other: &Self) -> bool {
        self.rect().overlaps(&other.rect())
    }

    fn rect(&self) -> Rect {
        Rect {
            x: self.x - self.size / 2.0,
            y: self.y - self.size / 2.0,
            w: self.size,
            h: self.size,
        }
    }
}

enum GameState {
    MainMenu,
    Playing,
    Paused,
    GameOver,
}

fn particle_explosion() -> particles::EmitterConfig {
    particles::EmitterConfig {
        local_coords: false,
        one_shot: true,
        emitting: true,
        lifetime: 0.6,
        lifetime_randomness: 0.3,
        explosiveness: 0.65,
        initial_direction_spread: 2.0 * std::f32::consts::PI,
        initial_velocity: 400.0,
        initial_velocity_randomness: 0.8,
        size: 16.0,
        size_randomness: 0.3,
        atlas: Some(AtlasConfig::new(5, 1, 0..)),
        ..Default::default()
    }
}

#[macroquad::main("Mitt spel")]
async fn main() {
    const MOVEMENT_SPEED: f32 = 200.0;

    rand::srand(miniquad::date::now() as u64);
    let mut squares = vec![];
    let mut bullets: Vec<Shape> = vec![];
    let mut circle = Shape {
        size: 32.0,
        speed: MOVEMENT_SPEED,
        x: screen_width() / 2.0,
        y: screen_height() / 2.0,
        collided: false,
    };
    let mut score: u32 = 0;
    let mut high_score: u32 = fs::read_to_string("highscore.dat")
        .map_or(Ok(0), |i| i.parse::<u32>())
        .unwrap_or(0);
    let mut game_state = GameState::MainMenu;

    let mut direction_modifier: f32 = 0.0;
    let render_target = render_target(320, 150);
    render_target.texture.set_filter(FilterMode::Nearest);
    let material = load_material(
        ShaderSource::Glsl {
            vertex: VERTEX_SHADER,
            fragment: FRAGMENT_SHADER,
        },
        MaterialParams {
            uniforms: vec![
                ("iResolution".to_owned(), UniformType::Float2),
                ("direction_modifier".to_owned(), UniformType::Float1),
            ],
            ..Default::default()
        },
    )
    .unwrap();

    let mut explosions: Vec<(Emitter, Vec2)> = vec![];

    set_pc_assets_folder("assets");
    let ship_texture: Texture2D = load_texture("ship.png").await.expect("Couldn't load file");
    ship_texture.set_filter(FilterMode::Nearest);
    let bullet_texture: Texture2D = load_texture("laser-bolts.png")
        .await
        .expect("Couldn't load file");
    bullet_texture.set_filter(FilterMode::Nearest);
    let explosion_texture: Texture2D = load_texture("explosion.png")
        .await
        .expect("Couldn't load file");
    explosion_texture.set_filter(FilterMode::Nearest);
    let enemy_small_texture: Texture2D = load_texture("enemy-small.png")
        .await
        .expect("Couldn't load file");
    enemy_small_texture.set_filter(FilterMode::Nearest);
    build_textures_atlas();

    let mut ship_sprite = AnimatedSprite::new(
        16,
        24,
        &[
            Animation {
                name: "idle".to_string(),
                row: 0,
                frames: 2,
                fps: 12,
            },
            Animation {
                name: "left".to_string(),
                row: 2,
                frames: 2,
                fps: 12,
            },
            Animation {
                name: "right".to_string(),
                row: 4,
                frames: 2,
                fps: 12,
            },
        ],
        true,
    );
    let mut bullet_sprite = AnimatedSprite::new(
        16,
        16,
        &[
            Animation {
                name: "bullet".to_string(),
                row: 0,
                frames: 2,
                fps: 12,
            },
            Animation {
                name: "bolt".to_string(),
                row: 1,
                frames: 2,
                fps: 12,
            },
        ],
        true,
    );
    bullet_sprite.set_animation(1);
    let mut enemy_small_sprite = AnimatedSprite::new(
        17,
        16,
        &[Animation {
            name: "enemy_small".to_string(),
            row: 0,
            frames: 2,
            fps: 12,
        }],
        true,
    );

    loop {
        clear_background(BLACK);

        material.set_uniform("iResolution", (screen_width(), screen_height()));
        material.set_uniform("direction_modifier", direction_modifier);
        gl_use_material(&material);
        draw_texture_ex(
            &render_target.texture,
            0.,
            0.,
            WHITE,
            DrawTextureParams {
                dest_size: Some(vec2(screen_width(), screen_height())),
                ..Default::default()
            },
        );
        gl_use_default_material();

        match game_state {
            GameState::MainMenu => {
                if is_key_pressed(KeyCode::Escape) {
                    std::process::exit(0);
                }
                if is_key_pressed(KeyCode::Space) {
                    squares.clear();
                    bullets.clear();
                    explosions.clear();
                    circle.x = screen_width() / 2.0;
                    circle.y = screen_height() / 2.0;
                    score = 0;
                    game_state = GameState::Playing;
                }
                let text = "Tryck på mellanslag";
                let text_dimensions = measure_text(text, None, 50, 1.0);
                draw_text(
                    text,
                    screen_width() / 2.0 - text_dimensions.width / 2.0,
                    screen_height() / 2.0,
                    50.0,
                    WHITE,
                );
            }
            GameState::Playing => {
                let delta_time = get_frame_time();
                ship_sprite.set_animation(0);
                if is_key_down(KeyCode::Right) {
                    circle.x += MOVEMENT_SPEED * delta_time;
                    direction_modifier += 0.05 * delta_time;
                    ship_sprite.set_animation(2);
                }
                if is_key_down(KeyCode::Left) {
                    circle.x -= MOVEMENT_SPEED * delta_time;
                    direction_modifier -= 0.05 * delta_time;
                    ship_sprite.set_animation(1);
                }
                if is_key_down(KeyCode::Down) {
                    circle.y += MOVEMENT_SPEED * delta_time;
                }
                if is_key_down(KeyCode::Up) {
                    circle.y -= MOVEMENT_SPEED * delta_time;
                }
                if is_key_pressed(KeyCode::Space) {
                    bullets.push(Shape {
                        x: circle.x,
                        y: circle.y - 24.0,
                        speed: circle.speed * 2.0,
                        size: 32.0,
                        collided: false,
                    });
                }
                if is_key_pressed(KeyCode::Escape) {
                    game_state = GameState::Paused;
                }

                // Clamp X and Y to be within the screen
                circle.x = circle.x.min(screen_width()).max(0.0);
                circle.y = circle.y.min(screen_height()).max(0.0);

                // Generate a new square
                if rand::gen_range(0, 99) >= 95 {
                    let size = rand::gen_range(16.0, 64.0);
                    squares.push(Shape {
                        size,
                        speed: rand::gen_range(50.0, 150.0),
                        x: rand::gen_range(size / 2.0, screen_width() - size / 2.0),
                        y: -size,
                        collided: false,
                    });
                }

                // Movement
                for square in &mut squares {
                    square.y += square.speed * delta_time;
                }
                for bullet in &mut bullets {
                    bullet.y -= bullet.speed * delta_time;
                }

                ship_sprite.update();
                bullet_sprite.update();
                enemy_small_sprite.update();

                // Remove shapes outside of screen
                squares.retain(|square| square.y < screen_height() + square.size);
                bullets.retain(|bullet| bullet.y > 0.0 - bullet.size / 2.0);

                // Remove collided shapes
                squares.retain(|square| !square.collided);
                bullets.retain(|bullet| !bullet.collided);

                // Remove old explosions
                explosions.retain(|(explosion, _)| explosion.config.emitting);

                // Check for collisions
                if squares.iter().any(|square| circle.collides_with(square)) {
                    if score == high_score {
                        fs::write("highscore.dat", high_score.to_string()).ok();
                    }
                    game_state = GameState::GameOver;
                }
                for square in squares.iter_mut() {
                    for bullet in bullets.iter_mut() {
                        if bullet.collides_with(square) {
                            bullet.collided = true;
                            square.collided = true;
                            score += square.size.round() as u32;
                            high_score = high_score.max(score);
                            explosions.push((
                                Emitter::new(EmitterConfig {
                                    amount: square.size.round() as u32 * 4,
                                    texture: Some(explosion_texture.clone()),
                                    ..particle_explosion()
                                }),
                                vec2(square.x, square.y),
                            ));
                        }
                    }
                }

                // Draw everything
                let bullet_frame = bullet_sprite.frame();
                for bullet in &bullets {
                    draw_texture_ex(
                        &bullet_texture,
                        bullet.x - bullet.size / 2.0,
                        bullet.y - bullet.size / 2.0,
                        WHITE,
                        DrawTextureParams {
                            dest_size: Some(vec2(bullet.size, bullet.size)),
                            source: Some(bullet_frame.source_rect),
                            ..Default::default()
                        },
                    );
                }
                let ship_frame = ship_sprite.frame();
                draw_texture_ex(
                    &ship_texture,
                    circle.x - ship_frame.dest_size.x,
                    circle.y - ship_frame.dest_size.y,
                    WHITE,
                    DrawTextureParams {
                        dest_size: Some(ship_frame.dest_size * 2.0),
                        source: Some(ship_frame.source_rect),
                        ..Default::default()
                    },
                );
                let enemy_frame = enemy_small_sprite.frame();
                for square in &squares {
                    draw_texture_ex(
                        &enemy_small_texture,
                        square.x - square.size / 2.0,
                        square.y - square.size / 2.0,
                        WHITE,
                        DrawTextureParams {
                            dest_size: Some(vec2(square.size, square.size)),
                            source: Some(enemy_frame.source_rect),
                            ..Default::default()
                        },
                    );
                }
                for (explosion, coords) in explosions.iter_mut() {
                    explosion.draw(*coords);
                }
                draw_text(
                    format!("Poäng: {}", score).as_str(),
                    10.0,
                    35.0,
                    25.0,
                    WHITE,
                );
                let highscore_text = format!("High score: {}", high_score);
                let text_dimensions = measure_text(highscore_text.as_str(), None, 25, 1.0);
                draw_text(
                    highscore_text.as_str(),
                    screen_width() - text_dimensions.width - 10.0,
                    35.0,
                    25.0,
                    WHITE,
                );
            }
            GameState::Paused => {
                if is_key_pressed(KeyCode::Escape) {
                    game_state = GameState::Playing;
                }
                let text = "Pausad";
                let text_dimensions = measure_text(text, None, 50, 1.0);
                draw_text(
                    text,
                    screen_width() / 2.0 - text_dimensions.width / 2.0,
                    screen_height() / 2.0,
                    50.0,
                    WHITE,
                );
            }
            GameState::GameOver => {
                if is_key_pressed(KeyCode::Space) {
                    game_state = GameState::MainMenu;
                }
                let text = "Game Over!";
                let text_dimensions = measure_text(text, None, 50, 1.0);
                draw_text(
                    text,
                    screen_width() / 2.0 - text_dimensions.width / 2.0,
                    screen_height() / 2.0,
                    50.0,
                    RED,
                );
            }
        }

        next_frame().await
    }
}
Agical