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use crate::types::{Coord3D, Line3D};
use geo::algorithm::line_intersection::{line_intersection, LineIntersection};
pub struct AdvancedNoder;
impl Default for AdvancedNoder {
fn default() -> Self {
Self::new()
}
}
impl AdvancedNoder {
pub fn new() -> Self {
Self
}
pub fn node(&self, lines: Vec<Line3D>) -> Vec<Line3D> {
let mut segments = lines;
let mut changed = true;
// Basic prototype: Repeated O(N^2) brute-force intersection finding.
// In a real advanced noder, this would be a sweep-line algorithm (e.g., Bentley-Ottmann)
// or a monotone-chain noder.
while changed {
changed = false;
let mut new_segments = Vec::with_capacity(segments.len());
let mut i = 0;
while i < segments.len() {
let s1 = segments[i];
let mut intersected = false;
for j in (i + 1)..segments.len() {
let s2 = segments[j];
// Simple bounding box check
let s1_min_x = f64::min(s1.start.x, s1.end.x);
let s1_max_x = f64::max(s1.start.x, s1.end.x);
let s1_min_y = f64::min(s1.start.y, s1.end.y);
let s1_max_y = f64::max(s1.start.y, s1.end.y);
let s2_min_x = f64::min(s2.start.x, s2.end.x);
let s2_max_x = f64::max(s2.start.x, s2.end.x);
let s2_min_y = f64::min(s2.start.y, s2.end.y);
let s2_max_y = f64::max(s2.start.y, s2.end.y);
if s1_max_x < s2_min_x
|| s1_min_x > s2_max_x
|| s1_max_y < s2_min_y
|| s1_min_y > s2_max_y
{
continue;
}
if let Some(intersection) = line_intersection(
geo::Line::new(s1.start.to_coord_2d(), s1.end.to_coord_2d()),
geo::Line::new(s2.start.to_coord_2d(), s2.end.to_coord_2d()),
) {
match intersection {
LineIntersection::SinglePoint {
intersection: pt, ..
} => {
let eps = 1e-9;
// Ignore intersections at existing endpoints
let s1_start_dist =
(pt.x - s1.start.x).powi(2) + (pt.y - s1.start.y).powi(2);
let s1_end_dist =
(pt.x - s1.end.x).powi(2) + (pt.y - s1.end.y).powi(2);
let s2_start_dist =
(pt.x - s2.start.x).powi(2) + (pt.y - s2.start.y).powi(2);
let s2_end_dist =
(pt.x - s2.end.x).powi(2) + (pt.y - s2.end.y).powi(2);
if s1_start_dist > eps
&& s1_end_dist > eps
&& s2_start_dist > eps
&& s2_end_dist > eps
{
// Found a true interior intersection!
// We'll interpolate Z just roughly for prototype.
let t1 = ((pt.x - s1.start.x).powi(2)
+ (pt.y - s1.start.y).powi(2))
.sqrt()
/ ((s1.end.x - s1.start.x).powi(2)
+ (s1.end.y - s1.start.y).powi(2))
.sqrt();
let z_interp = s1.start.z + t1 * (s1.end.z - s1.start.z);
let intersect_coord = Coord3D {
x: pt.x,
y: pt.y,
z: z_interp,
};
// Split both segments. For prototype, we'll just queue the splits and restart.
// Remove s2, replace it with splits
segments.remove(j);
let s2_1 = Line3D {
start: s2.start,
end: intersect_coord,
line_id: s2.line_id,
};
let s2_2 = Line3D {
start: intersect_coord,
end: s2.end,
line_id: s2.line_id,
};
if (s2_1.start.x - s2_1.end.x).powi(2)
+ (s2_1.start.y - s2_1.end.y).powi(2)
> eps
{
segments.push(s2_1);
}
if (s2_2.start.x - s2_2.end.x).powi(2)
+ (s2_2.start.y - s2_2.end.y).powi(2)
> eps
{
segments.push(s2_2);
}
// Split s1
let s1_1 = Line3D {
start: s1.start,
end: intersect_coord,
line_id: s1.line_id,
};
let s1_2 = Line3D {
start: intersect_coord,
end: s1.end,
line_id: s1.line_id,
};
if (s1_1.start.x - s1_1.end.x).powi(2)
+ (s1_1.start.y - s1_1.end.y).powi(2)
> eps
{
new_segments.push(s1_1);
}
if (s1_2.start.x - s1_2.end.x).powi(2)
+ (s1_2.start.y - s1_2.end.y).powi(2)
> eps
{
new_segments.push(s1_2);
}
intersected = true;
changed = true;
break;
}
}
LineIntersection::Collinear { .. } => {
// Ignore collinear overlaps in this simple prototype
}
}
}
}
if !intersected {
new_segments.push(s1);
}
i += 1;
}
if changed {
segments = new_segments;
}
}
segments
}
}