pix-engine 0.8.0

use anyhow::anyhow;
use pix_engine::prelude::*;
use std::{env, path::Path};

const WIDTH: u32 = 800;
const HEIGHT: u32 = 600;

struct ImageDemo(Image);

impl ImageDemo {
    fn new<P: AsRef<Path>>(png: P) -> PixResult<Self> {
        Ok(Self(Image::from_file(png)?))
    }
}

impl PixEngine for ImageDemo {
    fn on_start(&mut self, s: &mut PixState) -> PixResult<()> {
        s.blend_mode(BlendMode::Blend);
        s.image_mode(ImageMode::Center);
        Ok(())
    }

    fn on_update(&mut self, s: &mut PixState) -> PixResult<()> {
        s.clear()?;
        s.image(&self.0, [s.width()? as i32 / 2, s.height()? as i32 / 2])?;
        s.text("<Esc>: Disable Tint")?;
        s.text("<Return>: Random Tint")?;
        s.text("<Left>: Disable Blend Mode")?;
        s.text("<Right>: Alpha Blend Mode")?;
        s.text("<Up>: Additive Blend Mode")?;
        s.text("<Down>: Modulated Blend Mode")?;
        Ok(())
    }

    fn on_key_pressed(&mut self, s: &mut PixState, event: KeyEvent) -> PixResult<bool> {
        match event.key {
            Key::Escape => s.image_tint(None),
            Key::Return => s.image_tint(Color::random_alpha()),
            Key::Left => s.blend_mode(BlendMode::None),
            Key::Right => s.blend_mode(BlendMode::Blend),
            Key::Up => s.blend_mode(BlendMode::Add),
            Key::Down => s.blend_mode(BlendMode::Mod),
            _ => (),
        }
        Ok(false)
    }
}

fn main() -> PixResult<()> {
    let args: Vec<_> = env::args().collect();
    if args.len() < 2 {
        Err(anyhow!("Usage: cargo run /path/to/image.png"))
    } else {
        let mut engine = Engine::builder()
            .dimensions(WIDTH, HEIGHT)
            .title("Image Demo")
            .show_frame_rate()
            .build()?;
        let mut app = ImageDemo::new(&args[1])?;
        engine.run(&mut app)
    }
}