tawasuyu/llimphi

1//! Prueba de **sombras suaves** de una luz de interior: un piso con un par de
2//! objetos, iluminado por la lámpara como fuente de área (`PointLight.radius`) →
3//! penumbra que se abre con la distancia. `point_shadows` activo.
4//!
5//! `cargo run -p llimphi-voxel --example lit_demo --release` → `/tmp/lit.png`
6
7use std::fs::File;
8use std::io::BufWriter;
9
10use llimphi_3d::glam::Vec3;
11use llimphi_3d::{Atmosphere, Camera3d, PointLight, Scene3d, VoxelGrid, VoxelRenderer};
12use llimphi_hal::{wgpu, Hal};
13use llimphi_raster::peniko::Color;
14use llimphi_raster::{vello, Renderer};
15use llimphi_voxel::{stamp_mueble, Material, Mueble};
16
17const W: u32 = 1100;
18const H: u32 = 640;
19const FMT: wgpu::TextureFormat = wgpu::TextureFormat::Rgba8Unorm;
20
21fn main() {
22    let radius: f32 = std::env::args().nth(1).and_then(|s| s.parse().ok()).unwrap_or(2.0);
23    let dim = [56u32, 40, 48];
24    let mut g = VoxelGrid::new(dim);
25
26    // Piso liso de cerámica.
27    let floor_h = 2i32;
28    for x in 0..dim[0] {
29        for z in 0..dim[2] {
30            for y in 0..floor_h as u32 {
31                g.set(x, y, z, Material::Hormigon.color());
32            }
33        }
34    }
35
36    // Objetos que proyecten sombra sobre un piso amplio.
37    stamp_mueble(&mut g, Mueble::Silla, 26, floor_h as u32, 22, 2);
38    stamp_mueble(&mut g, Mueble::Barril, 34, floor_h as u32, 26, 0);
39    stamp_mueble(&mut g, Mueble::Ficus, 28, floor_h as u32, 32, 0);
40    // Un par de postes finos y altos: sombras largas y limpias para leer la penumbra.
41    for &px in &[18i32, 40] {
42        for dy in 0..12 {
43            g.set(px as u32, (floor_h + dy) as u32, 20, Material::Madera.color());
44        }
45    }
46    // La luz alta y a un lado (x bajo): sombras largas cruzando el piso hacia +x.
47    let light_pos = [10.0f32, floor_h as f32 + 16.0, 20.0];
48
49    let hal = pollster::block_on(Hal::new(None)).expect("hal");
50    let mut renderer = Renderer::new(&hal).expect("renderer");
51    let mut vr = VoxelRenderer::new(&hal.device, &hal.queue, FMT, &g);
52    vr.sun_dir = [0.3, 0.42, 0.4];
53    vr.atmosphere = Atmosphere {
54        sky_zenith: [30, 34, 46], // ambiente tenue pero visible
55        sky_horizon: [52, 50, 62],
56        fog_density: 0.0,
57        god_rays: 0.0,
58    };
59    vr.point_shadows = true;
60    vr.lights = vec![PointLight {
61        pos: light_pos,
62        color: [1.1, 0.92, 0.62], // cálida, sin reventar → el piso lit deja ver la sombra
63        range: 60.0,
64        radius, // fuente de área → penumbra
65    }];
66    eprintln!("radius de área = {radius} (0 = sombra dura; >0 = penumbra)");
67
68    let camera = Camera3d::orbit(
69        Vec3::new(2.0, floor_h as f32 * 0.4, 4.0),
70        20_f32.to_radians(),
71        26_f32.to_radians(),
72        dim[0] as f32 * 0.98,
73    );
74    let mut scene = Scene3d::new();
75    let pixels = render(&hal, &mut renderer, &mut scene, &mut vr, &camera);
76    write_png(&pixels, "/tmp/lit.png");
77    eprintln!("escrito /tmp/lit.png");
78}
79
80fn render(
81    hal: &Hal,
82    renderer: &mut Renderer,
83    scene: &mut Scene3d,
84    vr: &mut VoxelRenderer,
85    camera: &Camera3d,
86) -> Vec<u8> {
87    let inter = hal.device.create_texture(&wgpu::TextureDescriptor {
88        label: Some("inter"),
89        size: wgpu::Extent3d { width: W, height: H, depth_or_array_layers: 1 },
90        mip_level_count: 1,
91        sample_count: 1,
92        dimension: wgpu::TextureDimension::D2,
93        format: FMT,
94        usage: wgpu::TextureUsages::STORAGE_BINDING
95            | wgpu::TextureUsages::TEXTURE_BINDING
96            | wgpu::TextureUsages::RENDER_ATTACHMENT
97            | wgpu::TextureUsages::COPY_SRC,
98        view_formats: &[],
99    });
100    let view = inter.create_view(&wgpu::TextureViewDescriptor::default());
101    renderer
102        .render_to_view(hal, &vello::Scene::new(), &view, W, H, Color::from_rgba8(0, 0, 0, 255))
103        .expect("base");
104    let mut enc = hal
105        .device
106        .create_command_encoder(&wgpu::CommandEncoderDescriptor { label: Some("lit") });
107    scene.render(&hal.device, &hal.queue, &mut enc, &view, (W, H), camera, Some(vr), &[]);
108    hal.queue.submit(std::iter::once(enc.finish()));
109    let _ = hal.device.poll(wgpu::PollType::wait_indefinitely());
110    readback(hal, &inter)
111}
112
113fn readback(hal: &Hal, target: &wgpu::Texture) -> Vec<u8> {
114    let unpadded = (W * 4) as usize;
115    let align = wgpu::COPY_BYTES_PER_ROW_ALIGNMENT as usize;
116    let padded = unpadded.div_ceil(align) * align;
117    let buf = hal.device.create_buffer(&wgpu::BufferDescriptor {
118        label: Some("readback"),
119        size: (padded * H as usize) as u64,
120        usage: wgpu::BufferUsages::MAP_READ | wgpu::BufferUsages::COPY_DST,
121        mapped_at_creation: false,
122    });
123    let mut enc = hal
124        .device
125        .create_command_encoder(&wgpu::CommandEncoderDescriptor { label: None });
126    enc.copy_texture_to_buffer(
127        wgpu::TexelCopyTextureInfo {
128            texture: target,
129            mip_level: 0,
130            origin: wgpu::Origin3d::ZERO,
131            aspect: wgpu::TextureAspect::All,
132        },
133        wgpu::TexelCopyBufferInfo {
134            buffer: &buf,
135            layout: wgpu::TexelCopyBufferLayout {
136                offset: 0,
137                bytes_per_row: Some(padded as u32),
138                rows_per_image: Some(H),
139            },
140        },
141        wgpu::Extent3d { width: W, height: H, depth_or_array_layers: 1 },
142    );
143    hal.queue.submit(std::iter::once(enc.finish()));
144    let slice = buf.slice(..);
145    let (tx, rx) = std::sync::mpsc::channel();
146    slice.map_async(wgpu::MapMode::Read, move |r| {
147        let _ = tx.send(r);
148    });
149    let _ = hal.device.poll(wgpu::PollType::wait_indefinitely());
150    rx.recv().unwrap().unwrap();
151    let data = slice.get_mapped_range();
152    let mut pixels = Vec::with_capacity((W * H * 4) as usize);
153    for row in 0..H as usize {
154        let srow = row * padded;
155        pixels.extend_from_slice(&data[srow..srow + unpadded]);
156    }
157    drop(data);
158    buf.unmap();
159    pixels
160}
161
162fn write_png(pixels: &[u8], path: &str) {
163    let file = File::create(path).expect("png");
164    let mut enc = png::Encoder::new(BufWriter::new(file), W, H);
165    enc.set_color(png::ColorType::Rgba);
166    enc.set_depth(png::BitDepth::Eight);
167    let mut wtr = enc.write_header().unwrap();
168    wtr.write_image_data(pixels).unwrap();
169}