nordisk/facett

facett-helix/tests/tube_render.rs

//! **CPU render-proof for the 3D TubeView.** Run a real [`TubeView`] through
//! `egui_kittest` so the tube painter executes (project → depth-sort → shade → paint),
//! then prove the render is **non-blank with depth**: the pure projection produces many
//! visible, on-pane, multi-shaded faces, and driving it through `ui()` never panics.

use egui_kittest::Harness;

use facett_core::Facet;
use facett_helix::{TubeMsg, TubeView};

#[test]
fn tube_paints_non_blank_with_depth() {
    // Inject-assert the mesh first: a real tube, deterministically.
    let probe = TubeView::demo().with_clock(0.0);
    let st = probe.state_json();
    assert!(st["triangle_count"].as_u64().unwrap() > 200, "a real tube mesh");
    assert_eq!(st["valid"], true);

    // The pure render core: many visible, on-pane, multi-shaded faces (non-blank).
    let faces = probe.faces(640.0, 640.0);
    assert!(faces.len() > 200, "the tube projects many visible faces (got {})", faces.len());
    let mut shades = std::collections::HashSet::new();
    for f in &faces {
        let k = ((f.color.r() as u32 >> 3) << 10) | ((f.color.g() as u32 >> 3) << 5) | (f.color.b() as u32 >> 3);
        shades.insert(k);
    }
    assert!(shades.len() >= 8, "the lit, data-coloured tube shows many shades (got {})", shades.len());

    // Drive it through the egui immediate-mode surface — the painter must execute
    // without panicking (the headless CPU path, no wgpu adapter needed).
    let mut view = TubeView::demo().with_clock(0.0);
    let mut harness = Harness::builder().with_size(egui::vec2(640.0, 640.0)).build_ui(move |ui| {
        view.ui(ui);
    });
    harness.run();
}

#[test]
fn tube_state_is_data_and_deterministic() {
    // Two views at the same pinned clock produce identical observable state (FC-7).
    let a = TubeView::demo().with_clock(3.0);
    let b = TubeView::demo().with_clock(3.0);
    assert_eq!(a.state_json(), b.state_json(), "pinned clock ⇒ byte-identical state");
}

#[test]
fn tube_controls_are_addressable() {
    let mut v = TubeView::demo();
    assert!(v.update(TubeMsg::ToggleSpin(false)));
    assert_eq!(v.state_json()["spin"], false);
    assert!(v.update(TubeMsg::SetClock(2.5)));
    assert_eq!(v.state_json()["clock_s"], 2.5);
}