Display tessellation plans (1/4): planner with shared edge nodes (#802)
Adds TessPlan and the kernel planner (shared edge nodes, structured and Coons grids, constrained Delaunay for trimmed faces) behind Body::display_plan. Nothing drawn changes yet. Refs #303 Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
This commit is contained in:
Irakli KourtisandClaude Opus 5.5 authored and GitHub committed
1 parent
facff1050e
commit
bfbf5f9432
16 files changed
+2471
No files matched your search
@@ -0,0 +1,246 @@
|
||||
//! Parameters of points on a surface, on the evaluator's own surface form (so the parameters
|
||||
//! the plan stores are the ones the evaluators use), and the tolerance-driven divisions of a
|
||||
//! face's parameter box.
|
||||
|
||||
use solidcraft_geom::Vec3;
|
||||
use solidcraft_geom::tess::EvalSurface;
|
||||
|
||||
/// The parameter box of a surface and its periods.
|
||||
#[derive(Clone, Copy, Debug)]
|
||||
pub(crate) struct Domain {
|
||||
/// Bounded ranges (`None`: unbounded, as a plane's).
|
||||
pub range: [Option<(f64, f64)>; 2],
|
||||
pub period: [Option<f64>; 2],
|
||||
}
|
||||
|
||||
pub(crate) fn domain(s: &EvalSurface) -> Domain {
|
||||
let tau = std::f64::consts::TAU;
|
||||
match s {
|
||||
EvalSurface::Plane { .. } => Domain { range: [None, None], period: [None, None] },
|
||||
EvalSurface::Nurbs { degree, knots, count, .. } => {
|
||||
let r = |d: usize| Some((*knots[d].get(degree[d])?, *knots[d].get(count[d])?));
|
||||
Domain { range: [r(0), r(1)], period: [None, None] }
|
||||
}
|
||||
EvalSurface::Revolved { profile, swap, .. } => {
|
||||
let r = (|| Some((*profile.knots.get(profile.degree)?, *profile.knots.get(profile.ctrl.len())?)))();
|
||||
let (a, b) = ((r, None), (Some((0.0, tau)), Some(tau)));
|
||||
let (u, v) = if *swap { (b, a) } else { (a, b) };
|
||||
Domain { range: [u.0, v.0], period: [u.1, v.1] }
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
impl Domain {
|
||||
fn clamp(&self, uv: [f64; 2]) -> [f64; 2] {
|
||||
let mut out = uv;
|
||||
for (d, x) in out.iter_mut().enumerate() {
|
||||
if let (Some((a, b)), None) = (self.range[d], self.period[d]) {
|
||||
*x = x.clamp(a.min(b), a.max(b));
|
||||
}
|
||||
}
|
||||
out
|
||||
}
|
||||
}
|
||||
|
||||
/// Damped Gauss–Newton (Levenberg–Marquardt) for the parameters nearest to `p`, from `start`.
|
||||
/// Returns the parameters and their distance to `p`.
|
||||
fn newton(s: &EvalSurface, dom: &Domain, p: Vec3, start: [f64; 2]) -> Option<([f64; 2], f64)> {
|
||||
let mut uv = dom.clamp(start);
|
||||
let (mut q, mut su, mut sv) = s.derivs(uv[0], uv[1])?;
|
||||
let mut dist = q.dist(p);
|
||||
let mut lambda = 1e-6;
|
||||
for _ in 0..60 {
|
||||
let r = p - q;
|
||||
let (a, b, c) = (su.len2(), su.dot(sv), sv.len2());
|
||||
let (g0, g1) = (su.dot(r), sv.dot(r));
|
||||
let scale = a + c;
|
||||
if !(scale > 0.0) || !scale.is_finite() {
|
||||
break;
|
||||
}
|
||||
let (a2, c2) = (a + lambda * scale, c + lambda * scale);
|
||||
let det = a2 * c2 - b * b;
|
||||
if !(det.abs() > 0.0) {
|
||||
break;
|
||||
}
|
||||
let step = [(c2 * g0 - b * g1) / det, (a2 * g1 - b * g0) / det];
|
||||
let next = dom.clamp([uv[0] + step[0], uv[1] + step[1]]);
|
||||
let Some((nq, nsu, nsv)) = s.derivs(next[0], next[1]) else { break };
|
||||
let nd = nq.dist(p);
|
||||
if nd <= dist {
|
||||
let moved = (next[0] - uv[0]).abs() + (next[1] - uv[1]).abs();
|
||||
(uv, q, su, sv, dist) = (next, nq, nsu, nsv, nd);
|
||||
lambda = (lambda * 0.1).max(1e-12);
|
||||
if moved <= 1e-15 * (1.0 + uv[0].abs() + uv[1].abs()) {
|
||||
break;
|
||||
}
|
||||
} else {
|
||||
lambda *= 10.0;
|
||||
if lambda > 1e8 {
|
||||
break;
|
||||
}
|
||||
}
|
||||
}
|
||||
Some((uv, dist))
|
||||
}
|
||||
|
||||
/// Parameters of `p` (a point on the surface within `accept`), from `hint` when that
|
||||
/// converges, else from the best starts of a grid over the surface's domain.
|
||||
pub(crate) fn project(s: &EvalSurface, dom: &Domain, p: Vec3, hint: Option<[f64; 2]>, accept: f64) -> Option<[f64; 2]> {
|
||||
if let EvalSurface::Plane { origin, du, dv } = s {
|
||||
let r = p - *origin;
|
||||
let (a, b, c) = (du.len2(), du.dot(*dv), dv.len2());
|
||||
let det = a * c - b * b;
|
||||
if !(det.abs() > 0.0) {
|
||||
return None;
|
||||
}
|
||||
let (g0, g1) = (du.dot(r), dv.dot(r));
|
||||
let uv = [(c * g0 - b * g1) / det, (a * g1 - b * g0) / det];
|
||||
return (uv[0].is_finite() && uv[1].is_finite()).then_some(uv);
|
||||
}
|
||||
let mut best: Option<([f64; 2], f64)> = None;
|
||||
if let Some(h) = hint
|
||||
&& let Some((uv, d)) = newton(s, dom, p, h)
|
||||
{
|
||||
if d <= accept {
|
||||
return Some(uv);
|
||||
}
|
||||
best = Some((uv, d));
|
||||
}
|
||||
let (ur, vr) = (dom.range[0]?, dom.range[1]?);
|
||||
const N: usize = 16;
|
||||
let mut starts: Vec<(f64, [f64; 2])> = Vec::with_capacity((N + 1) * (N + 1));
|
||||
for i in 0..=N {
|
||||
for j in 0..=N {
|
||||
let uv = [ur.0 + (ur.1 - ur.0) * i as f64 / N as f64, vr.0 + (vr.1 - vr.0) * j as f64 / N as f64];
|
||||
if let Some((q, _, _)) = s.derivs(uv[0], uv[1]) {
|
||||
starts.push(((q - p).len2(), uv));
|
||||
}
|
||||
}
|
||||
}
|
||||
starts.sort_by(|a, b| a.0.total_cmp(&b.0));
|
||||
for (_, start) in starts.iter().take(4) {
|
||||
if let Some((uv, d)) = newton(s, dom, p, *start)
|
||||
&& best.is_none_or(|(_, bd)| d < bd)
|
||||
{
|
||||
best = Some((uv, d));
|
||||
}
|
||||
}
|
||||
best.filter(|(_, d)| *d <= accept).map(|(uv, _)| uv)
|
||||
}
|
||||
|
||||
/// `x` moved by whole periods to lie within half a period of `near`.
|
||||
pub(crate) fn unwrap(x: f64, near: f64, period: Option<f64>) -> f64 {
|
||||
match period {
|
||||
Some(p) if p > 0.0 => x - ((x - near) / p).round() * p,
|
||||
_ => x,
|
||||
}
|
||||
}
|
||||
|
||||
/// Is the surface degenerate along direction `d` at `uv` (a pole: moving along `d` does not
|
||||
/// move the point)?
|
||||
pub(crate) fn degenerate(s: &EvalSurface, uv: [f64; 2], d: usize) -> bool {
|
||||
let Some((_, su, sv)) = s.derivs(uv[0], uv[1]) else { return false };
|
||||
let (this, other) = if d == 0 { (su, sv) } else { (sv, su) };
|
||||
this.len() <= 1e-9 * other.len().max(1e-12)
|
||||
}
|
||||
|
||||
/// Division of `range` along direction `d` so that the surface between neighbouring lines
|
||||
/// sags at most `tol` from its chord, checked along iso-lines across `across`; at most
|
||||
/// `max_lines` lines, ends included.
|
||||
pub(crate) fn divide(s: &EvalSurface, d: usize, range: (f64, f64), across: (f64, f64), tol: f64, max_lines: usize) -> Vec<f64> {
|
||||
let (a0, a1) = range;
|
||||
if matches!(s, EvalSurface::Plane { .. }) || !(a1 > a0) {
|
||||
return vec![a0, a1];
|
||||
}
|
||||
let at = |x: f64, y: f64| {
|
||||
let (u, v) = if d == 0 { (x, y) } else { (y, x) };
|
||||
s.derivs(u, v).map(|(p, _, _)| p)
|
||||
};
|
||||
const ACROSS: usize = 5;
|
||||
let ys: Vec<f64> = (0..ACROSS).map(|k| across.0 + (across.1 - across.0) * k as f64 / (ACROSS - 1) as f64).collect();
|
||||
let flat = |a: f64, b: f64| {
|
||||
ys.iter().all(|&y| {
|
||||
let (Some(pa), Some(pb)) = (at(a, y), at(b, y)) else { return true };
|
||||
[0.25, 0.5, 0.75].iter().all(|f| at(a + (b - a) * f, y).is_none_or(|q| q.dist_to_segment(pa, pb) <= tol))
|
||||
})
|
||||
};
|
||||
// Start from quarter turns at most, so a closed iso-line is not taken for a flat one.
|
||||
let initial = ((a1 - a0) / std::f64::consts::FRAC_PI_2).ceil().clamp(1.0, 64.0) as u32;
|
||||
// Both ends exactly (a0 + (a1 − a0) · 1 may round away from a1): the end lines are the
|
||||
// face's own parameter box, which the boundary nodes sit on.
|
||||
let x_at = |i: u32| {
|
||||
let t = f64::from(i) / f64::from(initial);
|
||||
a0 * (1.0 - t) + a1 * t
|
||||
};
|
||||
let mut out = vec![a0];
|
||||
let mut stack: Vec<(f64, f64, u32)> = (0..initial).rev().map(|i| (x_at(i), x_at(i + 1), 0)).collect();
|
||||
while let Some((a, b, depth)) = stack.pop() {
|
||||
if depth >= 20 || out.len() + stack.len() >= max_lines.max(2) || flat(a, b) {
|
||||
out.push(b);
|
||||
} else {
|
||||
let m = 0.5 * (a + b);
|
||||
stack.push((m, b, depth + 1));
|
||||
stack.push((a, m, depth + 1));
|
||||
}
|
||||
}
|
||||
out
|
||||
}
|
||||
|
||||
#[cfg(test)]
|
||||
mod tests {
|
||||
use super::*;
|
||||
use solidcraft_geom::tess::EvalCurve;
|
||||
|
||||
fn cylinder() -> EvalSurface {
|
||||
EvalSurface::Revolved {
|
||||
profile: EvalCurve { degree: 1, knots: vec![0.0, 0.0, 1.0, 1.0], ctrl: vec![[3.0, 0.0, 0.0, 1.0], [3.0, 0.0, 4.0, 1.0]] },
|
||||
origin: Vec3::ZERO,
|
||||
axis: Vec3::Z,
|
||||
transform: [[1.0, 0.0, 0.0, 0.0], [0.0, 1.0, 0.0, 0.0], [0.0, 0.0, 1.0, 0.0]],
|
||||
swap: false,
|
||||
}
|
||||
}
|
||||
|
||||
#[test]
|
||||
fn projects_points_back_to_their_parameters() {
|
||||
let s = cylinder();
|
||||
let dom = domain(&s);
|
||||
for &(u, v) in &[(0.1, 0.2), (0.5, 3.0), (0.9, 6.0), (0.0, 1.0)] {
|
||||
let (p, _) = s.eval(u, v);
|
||||
let Some(uv) = project(&s, &dom, p, None, 1e-9) else { panic!("projects") };
|
||||
let (q, _) = s.eval(uv[0], uv[1]);
|
||||
assert!(q.dist(p) < 1e-9);
|
||||
assert!((uv[0] - u).abs() < 1e-9);
|
||||
}
|
||||
// Off the surface by more than `accept`: no parameters.
|
||||
assert!(project(&s, &dom, Vec3::new(5.0, 0.0, 1.0), None, 1e-3).is_none());
|
||||
}
|
||||
|
||||
#[test]
|
||||
fn divides_the_turn_but_not_the_straight_direction() {
|
||||
let s = cylinder();
|
||||
let turn = divide(&s, 1, (0.0, std::f64::consts::TAU), (0.0, 1.0), 0.01, 10_000);
|
||||
let along = divide(&s, 0, (0.0, 1.0), (0.0, std::f64::consts::TAU), 0.01, 10_000);
|
||||
assert_eq!(along, vec![0.0, 1.0]);
|
||||
// Chord sag r(1 − cos(θ/2)) ≤ 0.01 with r = 3 needs θ ≤ 0.163: at least 39 segments.
|
||||
assert!(turn.len() >= 40 && turn.len() < 80, "{}", turn.len());
|
||||
}
|
||||
|
||||
/// The first and last lines are the range's ends to the last bit: the boundary nodes sit on
|
||||
/// them, and a line a rounding inside would be taken for an interior one (a drill point's
|
||||
/// cone, where a0 + (a1 − a0) is not a1).
|
||||
#[test]
|
||||
fn divides_with_the_ends_exactly() {
|
||||
let (a0, a1) = (-1.010485317689877, 1.083909784703316);
|
||||
let lines = divide(&cylinder(), 1, (a0, a1), (0.0, 1.0), 0.01, 10_000);
|
||||
assert_eq!(lines.first().copied(), Some(a0));
|
||||
assert_eq!(lines.last().copied(), Some(a1));
|
||||
}
|
||||
|
||||
#[test]
|
||||
fn unwraps_across_the_period() {
|
||||
let tau = std::f64::consts::TAU;
|
||||
assert!((unwrap(0.1, tau - 0.1, Some(tau)) - (tau + 0.1)).abs() < 1e-12);
|
||||
assert_eq!(unwrap(0.1, 6.0, None), 0.1);
|
||||
}
|
||||
}
|
||||
Reference in new issue
Block a user