raytracing/src/scenes/scene.rs

use std::sync::Arc;

use rand::RngExt;
use serde::Deserialize;

use crate::{
    camera::Camera,
    objects::{
        materials::{
            dielectric::Dielectric,
            lambertian::{Lambertian, Metal},
            traits::Material,
        },
        sphere::Sphere,
        traits::Hittable,
    },
    scenes::{hittable_def::HittableDef, material_def::MaterialDef, raw_camera::RawCamera},
    vec3::Vec3,
};

#[derive(Debug)]
pub struct Scene {
    camera: Camera,
    objects: Vec<Arc<dyn Hittable>>,

    // image
    filename: String,
    image_width: u32,
    image_height: u32,

    // raytracing // TODO: think about organisation of these vars, also in Camera
    max_depth: u32,
}

impl Scene {
    pub fn new(
        camera: Camera,
        objects: Vec<Arc<dyn Hittable>>,
        filename: String,
        image_width: u32,
        image_height: u32,
        max_depth: u32,
    ) -> Self {
        Self {
            camera,
            objects,
            filename,
            image_width,
            image_height,
            max_depth,
        }
    }

    pub fn random() -> Self {
        let ground = Lambertian::rgb(-2.5, 0.5, 0.5, 1.);
        let mut world: Vec<Arc<dyn Hittable>> = vec![Arc::new(Sphere::xyz(
            0.,
            -1000.,
            0.,
            1000.,
            Arc::new(ground),
        ))];

        let mut rng = rand::rng();
        let point = Vec3::new(4., 0.2, 0.);
        for a in -11..11 {
            for b in -11..11 {
                let mat = rng.random_range((0.)..1.);
                let center = Vec3::new(
                    a as f32 + 0.9 * rng.random_range((0.)..1.),
                    0.2,
                    b as f32 + 0.9 * rng.random_range((0.)..1.),
                );

                if (center - point).length() > 0.9 {
                    if mat < 0.8 {
                        // diffuse
                        world.push(Arc::new(Sphere::new(
                            center,
                            0.2,
                            Arc::new(Lambertian::new(Vec3::random() * Vec3::random(), 1.)),
                        )));
                    } else if mat < 0.95 {
                        // metal
                        world.push(Arc::new(Sphere::new(
                            center,
                            0.2,
                            Arc::new(Metal::rgb(
                                rng.random_range(0.5..1.),
                                rng.random_range(0.5..1.),
                                rng.random_range(0.5..1.),
                                1.,
                                rng.random_range((0.)..0.5),
                            )),
                        )));
                    } else {
                        // glass
                        world.push(Arc::new(Sphere::new(
                            center,
                            0.2,
                            Arc::new(Dielectric::new(1.5)),
                        )));
                    }
                }
            }
        }

        world.push(Arc::new(Sphere::xyz(
            0.,
            1.,
            0.,
            1.,
            Arc::new(Dielectric::new(1.5)),
        )));
        world.push(Arc::new(Sphere::xyz(
            -4.,
            1.,
            0.,
            1.,
            Arc::new(Lambertian::rgb(0.4, 0.2, 0.1, 1.)),
        )));
        world.push(Arc::new(Sphere::xyz(
            4.,
            1.,
            0.,
            1.,
            Arc::new(Metal::rgb(0.7, 0.6, 0.5, 1., 0.)),
        )));

        let mut c = Camera::new();
        c.set_fov(20.);
        c.set_anti_alias_rate(2);
        c.set_vup(Vec3::new(0., 1., 0.));
        c.set_look_from(Vec3::new(13., 2., 3.));
        c.set_look_at(Vec3::new(0., 0., 0.));
        c.add_defocus_blur(0.6, 10.);

        Self {
            camera: c,
            objects: world,
            filename: "random.png".to_string(),
            image_width: 1920,
            image_height: 1080,
            max_depth: 50,
        }
    }

    pub fn get_camera(&self) -> &Camera {
        &self.camera
    }

    pub fn get_image_width(&self) -> u32 {
        self.image_width
    }

    pub fn get_image_height(&self) -> u32 {
        self.image_height
    }

    pub fn get_objects(&self) -> &Vec<Arc<dyn Hittable>> {
        &self.objects
    }

    pub fn get_max_depth(&self) -> u32 {
        self.max_depth
    }

    pub fn get_filename(&self) -> &String {
        &self.filename
    }

    pub fn init(&mut self) {
        self.camera
            .init(self.get_image_width(), self.get_image_height());
    }
}

#[derive(Deserialize)]
struct SceneDef {
    pub camera: RawCamera,
    pub materials: Vec<MaterialDef>,
    pub objects: Vec<HittableDef>,
    pub filename: String,
    pub image_width: u32,
    pub image_height: u32,
    pub max_depth: u32,
}

impl<'de> Deserialize<'de> for Scene {
    fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
    where
        D: serde::Deserializer<'de>,
    {
        let conc = SceneDef::deserialize(deserializer)?;
        let mats: Vec<Arc<dyn Material>> = conc
            .materials
            .into_iter()
            .map(MaterialDef::into_arc)
            .collect();
        let objs: Vec<Arc<dyn Hittable>> = conc
            .objects
            .into_iter()
            .filter_map(|h| h.into_arc(&mats))
            .collect();
        Ok(Self {
            camera: Camera::from(conc.camera),
            objects: objs,
            filename: conc.filename,
            image_width: conc.image_width,
            image_height: conc.image_height,
            max_depth: conc.max_depth,
        })
    }
}