ling_graphics/
window.rs

1use crate::camera::Camera3D;
2use crate::renderer::FrameBuffer;
3use crate::renderer::{Renderer, SoftwareRenderer};
4use crate::scene::{Scene, Transform as SceneTransform};
5use crate::viewport::Viewport;
6
7/// Terminal-based "window" that renders frames via `SoftwareRenderer`.
8///
9/// Renders a 3-D scene to an RGBA framebuffer then presents it either as
10/// coloured ANSI art in the terminal (`present_terminal`) or drives a full
11/// animation loop (`run`).
12pub struct Window {
13    pub viewport: Viewport,
14    renderer: SoftwareRenderer,
15    term_cols: usize,
16    term_rows: usize,
17}
18
19impl Window {
20    pub fn new(viewport: Viewport) -> Self {
21        Self {
22            viewport,
23            renderer: SoftwareRenderer::new(),
24            term_cols: 100,
25            term_rows: 40,
26        }
27    }
28
29    pub fn with_terminal_dimensions(mut self, cols: usize, rows: usize) -> Self {
30        self.term_cols = cols.max(10);
31        self.term_rows = rows.max(10);
32        self
33    }
34
35    /// Render the scene into the internal framebuffer and return a clone.
36    pub fn render_scene(&mut self, scene: &Scene, camera: &Camera3D) -> FrameBuffer {
37        self.renderer.begin_frame(
38            self.viewport.width,
39            self.viewport.height,
40            self.viewport.clear_color,
41        );
42
43        for &root in scene.roots() {
44            self.render_node_recursive(scene, root, camera, &scene.node(root).transform, 1.0);
45        }
46
47        self.renderer.end_frame().clone()
48    }
49
50    fn render_node_recursive(
51        &mut self,
52        scene: &Scene,
53        node_id: usize,
54        camera: &Camera3D,
55        _parent_transform: &SceneTransform,
56        _dummy_depth: f32,
57    ) {
58        let node = scene.node(node_id);
59        if node.visible {
60            if let (Some(mesh), Some(material)) = (node.mesh.as_ref(), node.material.as_ref()) {
61                let global = scene.global_transform(node_id);
62                let _ = global;
63                self.renderer
64                    .draw_mesh(mesh, &node.transform, material, camera);
65            }
66            // Collect children first to avoid borrow conflict
67            let children: Vec<usize> = node.children.clone();
68            let transform = node.transform.clone();
69            for child in children {
70                self.render_node_recursive(scene, child, camera, &transform, _dummy_depth);
71            }
72        }
73    }
74
75    /// Present the last rendered frame to the terminal as ANSI art.
76    pub fn present_terminal(&mut self) {
77        // Clone the framebuffer to release the mutable borrow on self.renderer
78        // before calling present_framebuffer_ascii which needs &self.
79        let fb = self.renderer.end_frame().clone();
80        self.present_framebuffer_ascii(&fb);
81    }
82
83    fn present_framebuffer_ascii(&self, fb: &FrameBuffer) {
84        let mut out = String::new();
85        out.push_str("\x1b[2J\x1b[H");
86
87        let w = fb.width as usize;
88        let h = fb.height as usize;
89        let step_x = (w / self.term_cols).max(1);
90        let step_y = (h / self.term_rows).max(1);
91
92        // Map luminance to ASCII density ramp
93        let chars = b" .:-=+*#%@";
94
95        for y in (0..h).step_by(step_y) {
96            for x in (0..w).step_by(step_x) {
97                let i = (y * w + x) * 4;
98                let r = fb.pixels[i] as f32 / 255.0;
99                let g = fb.pixels[i + 1] as f32 / 255.0;
100                let b = fb.pixels[i + 2] as f32 / 255.0;
101                let lum = 0.2126 * r + 0.7152 * g + 0.0722 * b;
102                let idx = ((lum.clamp(0.0, 1.0)) * ((chars.len() - 1) as f32)) as usize;
103                out.push(chars[idx] as char);
104            }
105            out.push('\n');
106        }
107
108        print!("{}", out);
109    }
110
111    /// Drive the render / tick / present loop for `max_frames` frames.
112    pub fn run(
113        &mut self,
114        mut scene: Scene,
115        mut camera: Camera3D,
116        mut tick: impl FnMut(u64, &mut Scene, &mut Camera3D),
117        max_frames: u64,
118    ) {
119        for frame in 0..max_frames {
120            tick(frame, &mut scene, &mut camera);
121
122            // Render → clone the framebuffer → present.
123            // Cloning releases the mutable borrow of self.renderer so that
124            // present_framebuffer_ascii can borrow self immutably.
125            let fb = self.render_scene(&scene, &camera);
126            self.present_framebuffer_ascii(&fb);
127        }
128    }
129}
ling_graphics/window.rs

ling_graphics/
window.rs
