tawasuyu/llimphi

1//! Demo headless de la **secuencia de nacimiento** (modos de cámara): un montaje
2//! 2×2 de cuatro momentos —
3//! 1. la cámara cae del cielo mirando abajo (ve el huevo),
4//! 2. casi tocando suelo (el huevo se raja),
5//! 3. recién nacido: la cámara sale del sujeto,
6//! 4. plano de seguimiento detrás del niño.
7//!
8//! `cargo run -p llimphi-voxel --example birth_demo --release` → `/tmp/birth.png`
9
10use std::fs::File;
11use std::io::BufWriter;
12
13use llimphi_3d::glam::Vec3;
14use llimphi_3d::{Atmosphere, Renderer3d, Scene3d, VoxelGrid, VoxelRenderer};
15use llimphi_hal::{wgpu, Hal};
16use llimphi_raster::peniko::Color;
17use llimphi_raster::{vello, Renderer};
18use llimphi_voxel::{Age, BirthSequence, Egg, Hatchling, Material};
19
20// Cada cuadro del montaje (mitad de un lienzo 960×540 → 2×2).
21const TW: u32 = 480;
22const TH: u32 = 270;
23const FMT: wgpu::TextureFormat = wgpu::TextureFormat::Rgba8Unorm;
24
25fn main() {
26    let hal = pollster::block_on(Hal::new(None)).expect("hal");
27    let mut renderer = Renderer::new(&hal).expect("renderer");
28
29    // Piso plano de arena, centrado en el origen.
30    let dim = [48u32, 28, 48];
31    let mut grid = VoxelGrid::new(dim);
32    for z in 0..dim[2] {
33        for x in 0..dim[0] {
34            grid.set(x, 0, z, Material::Sand.color());
35            grid.set(x, 1, z, Material::Sand.color());
36        }
37    }
38    grid.reset_dirty();
39    let feet_y = 2.0 - dim[1] as f32 / 2.0; // suelo en mundo
40
41    let mut vr = VoxelRenderer::new(&hal.device, &hal.queue, FMT, &grid);
42    vr.sun_dir = [0.5, 0.7, 0.4];
43    vr.atmosphere = Atmosphere { sky_zenith: [96, 150, 210], sky_horizon: [226, 208, 168], fog_density: 0.0 };
44
45    // Huevo en el centro, sobre el suelo. La secuencia hace caer la cámara sobre él.
46    let egg = Egg::new(Vec3::new(0.0, feet_y, 0.0), 1.4, Hatchling::human(Age::Baby));
47    let seq = BirthSequence::new(egg);
48
49    // Cuatro instantes clave de la secuencia.
50    let ts = [
51        seq.t_land * 0.35,           // cayendo, alto
52        seq.t_land * 0.93,           // casi en el suelo, el huevo se raja
53        seq.t_land + seq.t_pull * 0.5, // saliendo del sujeto
54        seq.duration(),              // seguimiento detrás del niño
55    ];
56
57    // Lienzo final 2×2.
58    let fw = TW * 2;
59    let fh = TH * 2;
60    let mut canvas = vec![0u8; (fw * fh * 4) as usize];
61
62    for (idx, &t) in ts.iter().enumerate() {
63        let mut egg_t = seq.egg;
64        egg_t.hatch = seq.hatch(t);
65        let camera = seq.camera(t);
66
67        let mut meshes: Vec<Renderer3d> = Vec::new();
68        let (ev, ei) = egg_t.mesh();
69        let mut er = Renderer3d::new(&hal.device, FMT);
70        er.set_geometry(&hal.device, &ev, &ei);
71        er.set_model(egg_t.model());
72        meshes.push(er);
73        // El recién nacido aparece una vez que el huevo está bien abierto.
74        if egg_t.hatch > 0.5 {
75            let baby = seq.newborn();
76            let (bv, bi) = baby.mesh();
77            let mut br = Renderer3d::new(&hal.device, FMT);
78            br.set_geometry(&hal.device, &bv, &bi);
79            br.set_model(baby.model());
80            meshes.push(br);
81        }
82
83        let refs: Vec<&Renderer3d> = meshes.iter().collect();
84        let mut scene = Scene3d::new();
85        let cam = {
86            let mut c = camera;
87            c.fovy_rad = 55_f32.to_radians();
88            c
89        };
90        let tile = render(&hal, &mut renderer, &mut scene, &mut vr, &refs, &cam);
91
92        // Pegar el cuadro en su celda del 2×2.
93        let (cx, cy) = ((idx as u32 % 2) * TW, (idx as u32 / 2) * TH);
94        for row in 0..TH {
95            let src = (row * TW * 4) as usize;
96            let dst = (((cy + row) * fw + cx) * 4) as usize;
97            canvas[dst..dst + (TW * 4) as usize].copy_from_slice(&tile[src..src + (TW * 4) as usize]);
98        }
99    }
100
101    write_png(&canvas, fw, fh, "/tmp/birth.png");
102    eprintln!("escrito /tmp/birth.png (caída · rajadura · nace · seguimiento)");
103}
104
105fn render(
106    hal: &Hal,
107    renderer: &mut Renderer,
108    scene: &mut Scene3d,
109    vr: &mut VoxelRenderer,
110    meshes: &[&Renderer3d],
111    camera: &llimphi_3d::Camera3d,
112) -> Vec<u8> {
113    let inter = hal.device.create_texture(&wgpu::TextureDescriptor {
114        label: Some("inter"),
115        size: wgpu::Extent3d { width: TW, height: TH, depth_or_array_layers: 1 },
116        mip_level_count: 1,
117        sample_count: 1,
118        dimension: wgpu::TextureDimension::D2,
119        format: FMT,
120        usage: wgpu::TextureUsages::STORAGE_BINDING
121            | wgpu::TextureUsages::TEXTURE_BINDING
122            | wgpu::TextureUsages::RENDER_ATTACHMENT
123            | wgpu::TextureUsages::COPY_SRC,
124        view_formats: &[],
125    });
126    let view = inter.create_view(&wgpu::TextureViewDescriptor::default());
127    // Fondo cielo (sin niebla los misses del voxel descartan a este color base).
128    renderer
129        .render_to_view(hal, &vello::Scene::new(), &view, TW, TH, Color::from_rgba8(150, 184, 224, 255))
130        .expect("base");
131    let mut enc = hal
132        .device
133        .create_command_encoder(&wgpu::CommandEncoderDescriptor { label: Some("birth") });
134    scene.render(&hal.device, &hal.queue, &mut enc, &view, (TW, TH), camera, Some(vr), meshes);
135    hal.queue.submit(std::iter::once(enc.finish()));
136    let _ = hal.device.poll(wgpu::PollType::wait_indefinitely());
137    readback(hal, &inter)
138}
139
140fn readback(hal: &Hal, target: &wgpu::Texture) -> Vec<u8> {
141    let unpadded = (TW * 4) as usize;
142    let align = wgpu::COPY_BYTES_PER_ROW_ALIGNMENT as usize;
143    let padded = unpadded.div_ceil(align) * align;
144    let buf = hal.device.create_buffer(&wgpu::BufferDescriptor {
145        label: Some("readback"),
146        size: (padded * TH as usize) as u64,
147        usage: wgpu::BufferUsages::MAP_READ | wgpu::BufferUsages::COPY_DST,
148        mapped_at_creation: false,
149    });
150    let mut enc = hal
151        .device
152        .create_command_encoder(&wgpu::CommandEncoderDescriptor { label: None });
153    enc.copy_texture_to_buffer(
154        wgpu::TexelCopyTextureInfo {
155            texture: target,
156            mip_level: 0,
157            origin: wgpu::Origin3d::ZERO,
158            aspect: wgpu::TextureAspect::All,
159        },
160        wgpu::TexelCopyBufferInfo {
161            buffer: &buf,
162            layout: wgpu::TexelCopyBufferLayout {
163                offset: 0,
164                bytes_per_row: Some(padded as u32),
165                rows_per_image: Some(TH),
166            },
167        },
168        wgpu::Extent3d { width: TW, height: TH, depth_or_array_layers: 1 },
169    );
170    hal.queue.submit(std::iter::once(enc.finish()));
171    let slice = buf.slice(..);
172    let (tx, rx) = std::sync::mpsc::channel();
173    slice.map_async(wgpu::MapMode::Read, move |r| {
174        let _ = tx.send(r);
175    });
176    let _ = hal.device.poll(wgpu::PollType::wait_indefinitely());
177    rx.recv().unwrap().unwrap();
178    let data = slice.get_mapped_range();
179    let mut pixels = Vec::with_capacity((TW * TH * 4) as usize);
180    for row in 0..TH as usize {
181        let s = row * padded;
182        pixels.extend_from_slice(&data[s..s + unpadded]);
183    }
184    drop(data);
185    buf.unmap();
186    pixels
187}
188
189fn write_png(pixels: &[u8], w: u32, h: u32, path: &str) {
190    let file = File::create(path).expect("png");
191    let mut enc = png::Encoder::new(BufWriter::new(file), w, h);
192    enc.set_color(png::ColorType::Rgba);
193    enc.set_depth(png::BitDepth::Eight);
194    let mut wtr = enc.write_header().unwrap();
195    wtr.write_image_data(pixels).unwrap();
196}