feat: test stuff

bampy/src/lib.rs

@@ -1,63 +1,25 @@
-use std::iter::empty;
-
 use approx::relative_eq;
-use nalgebra::{vector, SimdBool, Vector3};
-use serde::{Deserialize, Serialize};
-use slicer::{line::Line3, slice_rings::slice_rings};
-use tsify::Tsify;
+use nalgebra::{point, vector, Vector3};
+use result::{Slice, SliceOptions, SliceResult};
+use slicer::axis::Axis;
 use wasm_bindgen::prelude::wasm_bindgen;
 
-use crate::slicer::{
-    base_slices::create_base_slices, mesh::Mesh, split_surface::split_surface,
-    trace_surface::trace_surface, triangle::Triangle, FloatValue, SlicerOptions,
-};
+use crate::slicer::{mesh::Mesh, split_surface::split_surface, triangle::Triangle, FloatValue};
 
+mod result;
 mod slicer;
 mod util;
 
 const BED_NORMAL: Vector3<f64> = vector![0f64, 0f64, 1f64];
 
-#[derive(Tsify, Serialize, Deserialize)]
-#[serde(rename_all = "camelCase")]
-#[tsify(from_wasm_abi)]
-pub struct SliceOptions {
-    #[tsify(type = "Float32Array")]
-    positions: Vec<f32>,
-    layer_height: f64,
-    max_angle: f64,
-}
-
-#[derive(Tsify, Serialize, Deserialize)]
-#[serde(rename_all = "camelCase", tag = "type")]
-#[tsify(into_wasm_abi)]
-pub enum Slice {
-    Surface {
-        #[tsify(type = "Float32Array")]
-        position: Vec<f32>,
-    },
-    Ring {
-        #[tsify(type = "Float32Array")]
-        position: Vec<f32>,
-    },
-    Path {
-        #[tsify(type = "Float32Array")]
-        position: Vec<f32>,
-    },
-}
-
-#[derive(Tsify, Serialize, Deserialize)]
-#[serde(rename_all = "camelCase")]
-#[tsify(into_wasm_abi)]
-pub struct SliceResult {
-    slices: Vec<Slice>,
-}
-
 #[wasm_bindgen]
 pub fn slice(
     SliceOptions {
         positions,
         layer_height,
         max_angle,
+        min_surface_path_length,
+        nozzle_diameter,
     }: SliceOptions,
 ) -> SliceResult {
     std::panic::set_hook(Box::new(console_error_panic_hook::hook));
@@ -68,17 +30,17 @@ pub fn slice(
     let mut slicable_triangles = Vec::<Triangle>::with_capacity(positions.len() / 9);
     for i in (0..positions.len()).step_by(9) {
         let triangle = Triangle::new(
-            vector![
+            point![
                 positions[i] as FloatValue,
                 positions[i + 1] as FloatValue,
                 positions[i + 2] as FloatValue
             ],
-            vector![
+            point![
                 positions[i + 3] as FloatValue,
                 positions[i + 4] as FloatValue,
                 positions[i + 5] as FloatValue
             ],
-            vector![
+            point![
                 positions[i + 6] as FloatValue,
                 positions[i + 7] as FloatValue,
                 positions[i + 8] as FloatValue
@@ -99,50 +61,23 @@ pub fn slice(
     slicable_triangles.shrink_to_fit();
     surface_triangles.shrink_to_fit();
 
-    let slicer_options = SlicerOptions { layer_height };
-
     console_log!("Creating Surfaces");
     let surfaces = split_surface(surface_triangles).into_iter().map(|mesh| {
-        slice_rings(1, &slicer_options, &mesh)
-            .flat_map(|mut rings| {
-                /*let mut rings = rings
-                .into_iter()
-                .map(|mut ring| {
-                    ring.points.sort_unstable_by(|a, b| {
-                        a[0].partial_cmp(&b[0]).unwrap_or(std::cmp::Ordering::Equal)
-                    });
-                    ring
-                })
-                .collect::<Vec<_>>();*/
-                rings.sort_unstable_by(|a, b| {
-                    a.points
-                        .first()
-                        .unwrap()
-                        .partial_cmp(b.points.first().unwrap())
-                        .unwrap_or(std::cmp::Ordering::Equal)
-                });
-                rings
-            })
-            .fold(Vec::<Vector3<FloatValue>>::new(), |mut acc, mut curr| {
-                if acc
-                    .last()
-                    .zip(curr.points.first())
-                    .zip(curr.points.last())
-                    .map_or(false, |((last, start), end)| {
-                        start.metric_distance(last) > end.metric_distance(last)
-                    })
-                {
-                    curr.points.reverse();
+        mesh.slice_surface(Axis::X, nozzle_diameter).filter(|path| {
+            let mut length = 0.0;
+            for pair in path.path.windows(2) {
+                length += (pair[0].coords - pair[1].coords).norm();
+                if length >= min_surface_path_length {
+                    return true;
                 }
-                acc.extend(curr.points);
-                acc
-            })
+            }
+            return false;
+        })
     });
 
-    console_log!("Computing BVH");
-    let slicable = Mesh::from(slicable_triangles);
-    console_log!("Creating Slices");
-    let slices = slice_rings(2, &slicer_options, &slicable);
+    console_log!("Creating Walls");
+    let wallMesh = Mesh::from(slicable_triangles);
+    let walls = wallMesh.slice_paths(Axis::Z, layer_height);
 
     /*console_log!("Tracing Surfaces");
     let a = max_angle.tan();
@@ -157,13 +92,15 @@ pub fn slice(
     console_log!("Done");
     SliceResult {
         slices: surfaces
+            .flatten()
             .map(|slice| Slice::Ring {
                 position: slice
+                    .path
                     .into_iter()
                     .flat_map(|point| [point.x as f32, point.y as f32, point.z as f32])
                     .collect(),
             })
-            /*.chain(slices.flatten().map(|slice| {
+            /*.chain(walls.flatten().map(|slice| {
                 Slice::Ring {
                     position: slice
                         .points

bampy/src/result.rs

@@ -0,0 +1,39 @@
+use serde::{Deserialize, Serialize};
+use tsify::Tsify;
+
+#[derive(Tsify, Serialize, Deserialize)]
+#[serde(rename_all = "camelCase")]
+#[tsify(from_wasm_abi)]
+pub struct SliceOptions {
+    #[tsify(type = "Float32Array")]
+    pub positions: Vec<f32>,
+    pub layer_height: f64,
+    pub nozzle_diameter: f64,
+    pub max_angle: f64,
+    pub min_surface_path_length: f64,
+}
+
+#[derive(Tsify, Serialize, Deserialize)]
+#[serde(rename_all = "camelCase", tag = "type")]
+#[tsify(into_wasm_abi)]
+pub enum Slice {
+    Surface {
+        #[tsify(type = "Float32Array")]
+        position: Vec<f32>,
+    },
+    Ring {
+        #[tsify(type = "Float32Array")]
+        position: Vec<f32>,
+    },
+    Path {
+        #[tsify(type = "Float32Array")]
+        position: Vec<f32>,
+    },
+}
+
+#[derive(Tsify, Serialize, Deserialize)]
+#[serde(rename_all = "camelCase")]
+#[tsify(into_wasm_abi)]
+pub struct SliceResult {
+    pub slices: Vec<Slice>,
+}

bampy/src/slicer/axis.rs

@@ -0,0 +1,29 @@
+use nalgebra::Vector3;
+
+use super::FloatValue;
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+#[repr(usize)]
+pub enum Axis {
+    X = 0,
+    Y = 1,
+    Z = 2,
+}
+
+impl Axis {
+    pub fn other(&self) -> (Self, Self) {
+        match self {
+            Axis::X => (Axis::Y, Axis::Z),
+            Axis::Y => (Axis::X, Axis::Z),
+            Axis::Z => (Axis::X, Axis::Y),
+        }
+    }
+
+    pub fn normal(&self) -> Vector3<FloatValue> {
+        match self {
+            Axis::X => Vector3::x(),
+            Axis::Y => Vector3::y(),
+            Axis::Z => Vector3::z(),
+        }
+    }
+}

bampy/src/slicer/base_slices.rs

@@ -1,62 +1,82 @@
-use super::{line::Line3, mesh::Mesh, FloatValue, SlicerOptions};
-use crate::console_log;
-use bvh::bvh::BvhNode;
+use super::{aabb_from_points, axis::Axis, line::Line3, slice_path::SlicePath, FloatValue};
+use approx::relative_eq;
+use nalgebra::Point3;
 
 #[derive(Debug)]
 pub struct BaseSlice {
+    pub i: usize,
     pub d: FloatValue,
+    pub axis: Axis,
     pub lines: Vec<Line3>,
 }
 
-/// Creates base slices from the geometry
-pub fn create_base_slices<'a>(
-    axis: usize,
-    options: &'a SlicerOptions,
-    slicable: &'a Mesh,
-) -> impl Iterator<Item = BaseSlice> + 'a {
-    let layer_count = ((slicable.aabb.max[axis] - slicable.aabb.min[axis]) / options.layer_height)
-        .floor() as usize;
-
-    (0..layer_count).map(move |i| {
-        let layer = i as FloatValue * options.layer_height + slicable.aabb.min[axis];
-        let mut base_slice = BaseSlice {
-            d: layer,
-            lines: vec![],
-        };
-
-        let mut stack = Vec::<usize>::with_capacity(slicable.bvh.nodes.len());
-        stack.push(0);
-        while let Some(i) = stack.pop() {
-            match slicable.bvh.nodes[i] {
-                BvhNode::Node {
-                    parent_index: _,
-                    child_l_index,
-                    child_l_aabb,
-                    child_r_index,
-                    child_r_aabb,
-                } => {
-                    assert!(child_l_aabb.min[axis] <= child_l_aabb.max[axis]);
-                    assert!(child_r_aabb.min[axis] <= child_r_aabb.max[axis]);
-                    if layer >= child_l_aabb.min[axis] && layer <= child_l_aabb.max[axis] {
-                        stack.push(child_l_index);
-                    }
-                    if layer >= child_r_aabb.min[axis] && layer <= child_r_aabb.max[axis] {
-                        stack.push(child_r_index);
-                    }
-                }
-                BvhNode::Leaf {
-                    parent_index: _,
-                    shape_index,
-                } => {
-                    slicable.triangles[shape_index]
-                        .intersect(layer, axis)
-                        .map(|line| {
-                            base_slice.lines.push(line);
-                        });
-                }
+impl BaseSlice {
+    pub fn find_paths(mut self) -> Vec<SlicePath> {
+        let (axis_a, axis_b) = self.axis.other();
+        let mut rings = vec![];
+        while let Some(line) = self.lines.pop() {
+            if relative_eq!(line.start, line.end) {
+                continue;
             }
+            let mut right = vec![line.end];
+            let mut left = vec![line.start];
+            let mut previous_len = usize::MAX;
+            let mut closed = false;
+
+            while !closed {
+                if previous_len == self.lines.len() {
+                    break;
+                }
+                previous_len = self.lines.len();
+
+                self.lines.retain_mut(|line| {
+                    if closed {
+                        return true;
+                    }
+
+                    let test = |side: &mut Vec<Point3<FloatValue>>| {
+                        let last = side.last().unwrap();
+                        let s = relative_eq!(line.start, last);
+                        let e = relative_eq!(line.end, last);
+                        if s && !e {
+                            side.push(line.end);
+                        } else if !s && e {
+                            side.push(line.start);
+                        }
+                        s || e
+                    };
+
+                    if test(&mut left) || test(&mut right) {
+                        closed = relative_eq!(left.last().unwrap(), right.last().unwrap());
+                        false
+                    } else {
+                        true
+                    }
+                })
+            }
+
+            left.reverse();
+            left.extend(right);
+            let mut ring = SlicePath {
+                d: self.d,
+                i: self.i,
+                axis: self.axis,
+                closed,
+                aabb: aabb_from_points(left.iter()),
+                points: left,
+            };
+
+            if ring.points.windows(2).fold(0.0, |acc, curr| {
+                acc + (curr[1][axis_a as usize] - curr[0][axis_a as usize])
+                    * (curr[1][axis_b as usize] + curr[0][axis_b as usize])
+            }) < 0.0
+            {
+                ring.points.reverse();
+            }
+
+            rings.push(ring);
         }
 
-        base_slice
-    })
+        rings
+    }
 }

bampy/src/slicer/line.rs

@@ -1,4 +1,4 @@
-use nalgebra::Vector3;
+use nalgebra::{Point3, Vector3};
 
 use super::FloatValue;
 
@@ -8,6 +8,16 @@ use super::FloatValue;
 /// meaning the inside is on the right hand side of the line.
 #[derive(Debug, PartialEq, Clone, Copy)]
 pub struct Line3 {
-    pub start: Vector3<FloatValue>,
-    pub end: Vector3<FloatValue>,
+    pub start: Point3<FloatValue>,
+    pub end: Point3<FloatValue>,
+}
+
+impl Line3 {
+    pub fn norm(&self) -> FloatValue {
+        (self.end - self.start).norm()
+    }
+
+    pub fn normal(&self) -> Vector3<FloatValue> {
+        (self.end - self.start).normalize()
+    }
 }

bampy/src/slicer/mesh.rs

@@ -1,5 +1,14 @@
-use super::{triangle::Triangle, FloatValue};
-use bvh::{aabb::Aabb, bvh::Bvh};
+use super::{
+    axis::Axis,
+    base_slices::BaseSlice,
+    slice_path::{SlicePath, SurfacePathIterator},
+    triangle::Triangle,
+    FloatValue,
+};
+use bvh::{
+    aabb::Aabb,
+    bvh::{Bvh, BvhNode},
+};
 
 #[derive(Debug)]
 pub struct Mesh {
@@ -26,3 +35,76 @@ impl From<Vec<Triangle>> for Mesh {
         }
     }
 }
+
+impl Mesh {
+    pub fn slice_paths<'a>(
+        self: &'a Mesh,
+        axis: Axis,
+        slice_height: FloatValue,
+    ) -> impl Iterator<Item = Vec<SlicePath>> + 'a {
+        self.slice_base_slices(axis, slice_height)
+            .map(|slice| slice.find_paths())
+            .filter(|paths| !paths.is_empty())
+    }
+
+    pub fn slice_surface(&self, axis: Axis, nozzle_width: FloatValue) -> SurfacePathIterator {
+        SurfacePathIterator::new(self, axis, nozzle_width)
+    }
+
+    pub fn slice_base_slices<'a>(
+        self: &'a Mesh,
+        axis: Axis,
+        slice_height: FloatValue,
+    ) -> impl Iterator<Item = BaseSlice> + 'a {
+        let layer_count = ((self.aabb.max[axis as usize] - self.aabb.min[axis as usize])
+            / slice_height)
+            .floor() as usize;
+
+        (0..layer_count).map(move |i| {
+            let layer = i as FloatValue * slice_height + self.aabb.min[axis as usize];
+            let mut base_slice = BaseSlice {
+                i,
+                d: layer,
+                axis,
+                lines: vec![],
+            };
+
+            let mut stack = Vec::<usize>::with_capacity(self.bvh.nodes.len());
+            stack.push(0);
+            while let Some(i) = stack.pop() {
+                match self.bvh.nodes[i] {
+                    BvhNode::Node {
+                        parent_index: _,
+                        child_l_index,
+                        child_l_aabb,
+                        child_r_index,
+                        child_r_aabb,
+                    } => {
+                        assert!(child_l_aabb.min[axis as usize] <= child_l_aabb.max[axis as usize]);
+                        assert!(child_r_aabb.min[axis as usize] <= child_r_aabb.max[axis as usize]);
+                        if layer >= child_l_aabb.min[axis as usize]
+                            && layer <= child_l_aabb.max[axis as usize]
+                        {
+                            stack.push(child_l_index);
+                        }
+                        if layer >= child_r_aabb.min[axis as usize]
+                            && layer <= child_r_aabb.max[axis as usize]
+                        {
+                            stack.push(child_r_index);
+                        }
+                    }
+                    BvhNode::Leaf {
+                        parent_index: _,
+                        shape_index,
+                    } => {
+                        for line in self.triangles[shape_index].intersect(layer, axis as usize) {
+                            base_slice.lines.push(line);
+                        }
+                    }
+                }
+            }
+
+            base_slice
+        })
+    }
+}

bampy/src/slicer/mod.rs

@@ -1,9 +1,13 @@
-use std::fmt::Debug;
+use bvh::aabb::{Aabb, Bounded};
+use bvh::bounding_hierarchy::BHValue;
+use nalgebra::Point;
 
+pub mod axis;
 pub mod base_slices;
 pub mod line;
 pub mod mesh;
-pub mod slice_rings;
+pub mod sdf;
+pub mod slice_path;
 pub mod split_surface;
 pub mod trace_surface;
 pub mod triangle;
@@ -11,7 +15,17 @@ pub mod z_projection;
 
 pub type FloatValue = f64;
 
-#[derive(Debug)]
-pub struct SlicerOptions {
-    pub layer_height: FloatValue,
+pub fn aabb_from_points<'a, I, T: BHValue, const D: usize>(mut points: I) -> Aabb<T, D>
+where
+    I: Iterator<Item = &'a Point<T, D>>,
+{
+    if let Some(point) = points.next() {
+        let mut aabb = point.aabb();
+        for point in points {
+            aabb.grow_mut(point);
+        }
+        aabb
+    } else {
+        Aabb::empty()
+    }
 }

bampy/src/slicer/sdf.rs

@@ -0,0 +1,253 @@
+/// https://iquilezles.org/articles/distfunctions/
+use nalgebra::{vector, Point, TAffine, Transform, Vector2, Vector3};
+
+use super::FloatValue;
+
+pub trait Sdf<const D: usize> {
+    fn sdf(&self, p: Point<FloatValue, D>) -> FloatValue;
+}
+
+#[derive(Debug, Clone, Copy)]
+pub struct SdfSphere {
+    radius: FloatValue,
+}
+
+impl SdfSphere {
+    pub fn new(radius: FloatValue) -> Self {
+        Self { radius }
+    }
+}
+
+impl Sdf<3> for SdfSphere {
+    fn sdf(&self, p: Point<FloatValue, 3>) -> FloatValue {
+        p.coords.norm() - self.radius
+    }
+}
+
+#[derive(Debug, Clone, Copy)]
+pub struct SdfBox {
+    size: Point<FloatValue, 3>,
+}
+
+impl SdfBox {
+    pub fn new(size: Point<FloatValue, 3>) -> Self {
+        Self { size }
+    }
+}
+
+impl Sdf<3> for SdfBox {
+    fn sdf(&self, p: Point<FloatValue, 3>) -> FloatValue {
+        let q = p.coords.abs() - self.size.coords;
+        q.sup(&Vector3::zeros()).add_scalar(q.max().min(0.0)).norm()
+    }
+}
+
+#[derive(Debug, Clone, Copy)]
+pub struct SdfInfiniteCone {
+    angle: Vector2<FloatValue>,
+}
+
+impl SdfInfiniteCone {
+    pub fn new(angle: FloatValue) -> Self {
+        Self {
+            angle: vector![angle.sin(), angle.cos()],
+        }
+    }
+}
+
+impl Sdf<3> for SdfInfiniteCone {
+    fn sdf(&self, p: Point<FloatValue, 3>) -> FloatValue {
+        let q = vector![p.coords.xy().norm(), p.z];
+        let d = (q - self.angle.scale(q.dot(&self.angle).max(0.0))).norm();
+        if q.x * self.angle.y - q.y * self.angle.x > 0.0 {
+            d
+        } else {
+            -d
+        }
+    }
+}
+
+#[derive(Debug, Clone, Copy)]
+pub struct SdfTransform<T: Sdf<3>> {
+    sdf: T,
+    transform: Transform<FloatValue, TAffine, 3>,
+}
+
+impl<T: Sdf<3>> SdfTransform<T> {
+    fn new(sdf: T, transform: Transform<FloatValue, TAffine, 3>) -> Self {
+        Self { sdf, transform }
+    }
+}
+
+impl<T: Sdf<3>> Sdf<3> for SdfTransform<T> {
+    fn sdf(&self, p: Point<FloatValue, 3>) -> FloatValue {
+        self.sdf.sdf(self.transform.inverse_transform_point(&p))
+    }
+}
+
+#[derive(Debug, Clone, Copy)]
+pub struct SdfScale<const D: usize, T: Sdf<D>> {
+    sdf: T,
+    scale: FloatValue,
+}
+
+impl<const D: usize, T: Sdf<D>> SdfScale<D, T> {
+    fn new(sdf: T, scale: FloatValue) -> Self {
+        Self { sdf, scale }
+    }
+}
+
+impl<const D: usize, T: Sdf<D>> Sdf<D> for SdfScale<D, T> {
+    fn sdf(&self, p: Point<FloatValue, D>) -> FloatValue {
+        self.sdf.sdf(p / self.scale) * self.scale
+    }
+}
+
+#[derive(Debug, Clone, Copy)]
+pub struct SdfOnion<T: Sdf<3>> {
+    sdf: T,
+    thickness: FloatValue,
+}
+
+impl<T: Sdf<3>> SdfOnion<T> {
+    fn new(sdf: T, thickness: FloatValue) -> Self {
+        Self { sdf, thickness }
+    }
+}
+
+impl<T: Sdf<3>> Sdf<3> for SdfOnion<T> {
+    fn sdf(&self, p: Point<FloatValue, 3>) -> FloatValue {
+        self.sdf.sdf(p).abs() - self.thickness
+    }
+}
+
+#[derive(Debug, Clone, Copy)]
+pub struct SdfUnion<const D: usize, T: Sdf<D>, U: Sdf<D>> {
+    sdf_a: T,
+    sdf_b: U,
+}
+
+impl<const D: usize, T: Sdf<D>, U: Sdf<D>> SdfUnion<D, T, U> {
+    fn new(sdf_a: T, sdf_b: U) -> Self {
+        Self { sdf_a, sdf_b }
+    }
+}
+
+impl<const D: usize, T: Sdf<D>, U: Sdf<D>> Sdf<D> for SdfUnion<D, T, U> {
+    fn sdf(&self, p: Point<FloatValue, D>) -> FloatValue {
+        self.sdf_a.sdf(p).min(self.sdf_b.sdf(p))
+    }
+}
+
+#[derive(Debug, Clone, Copy)]
+pub struct SdfIntersection<const D: usize, T: Sdf<D>, U: Sdf<D>> {
+    sdf_a: T,
+    sdf_b: U,
+}
+
+impl<const D: usize, T: Sdf<D>, U: Sdf<D>> SdfIntersection<D, T, U> {
+    fn new(sdf_a: T, sdf_b: U) -> Self {
+        Self { sdf_a, sdf_b }
+    }
+}
+
+impl<const D: usize, T: Sdf<D>, U: Sdf<D>> Sdf<D> for SdfIntersection<D, T, U> {
+    fn sdf(&self, p: Point<FloatValue, D>) -> FloatValue {
+        self.sdf_a.sdf(p).max(self.sdf_b.sdf(p))
+    }
+}
+
+#[derive(Debug, Clone, Copy)]
+pub struct SdfDifference<const D: usize, T: Sdf<D>, U: Sdf<D>> {
+    sdf_a: T,
+    sdf_b: U,
+}
+
+impl<const D: usize, T: Sdf<D>, U: Sdf<D>> SdfDifference<D, T, U> {
+    fn new(sdf_a: T, sdf_b: U) -> Self {
+        Self { sdf_a, sdf_b }
+    }
+}
+
+impl<const D: usize, T: Sdf<D>, U: Sdf<D>> Sdf<D> for SdfDifference<D, T, U> {
+    fn sdf(&self, p: Point<FloatValue, D>) -> FloatValue {
+        self.sdf_a.sdf(p).max(-self.sdf_b.sdf(p))
+    }
+}
+
+pub trait SdfOperators<const D: usize>: Sdf<D> {
+    fn union(self, other: Self) -> SdfUnion<D, Self, Self>
+    where
+        Self: Sized,
+    {
+        SdfUnion::new(self, other)
+    }
+
+    fn intersection(self, other: Self) -> SdfIntersection<D, Self, Self>
+    where
+        Self: Sized,
+    {
+        SdfIntersection::new(self, other)
+    }
+
+    fn difference(self, other: Self) -> SdfDifference<D, Self, Self>
+    where
+        Self: Sized,
+    {
+        SdfDifference::new(self, other)
+    }
+}
+
+impl<const D: usize, T: Sdf<D>> SdfOperators<D> for T {}
+
+pub trait Sdf3dModifiers: Sdf<3> {
+    /// exact
+    fn transform(self, transform: Transform<FloatValue, TAffine, 3>) -> SdfTransform<Self>
+    where
+        Self: Sized,
+    {
+        SdfTransform::new(self, transform)
+    }
+
+    /// exact
+    fn translate(self, translation: Point<FloatValue, 3>) -> SdfTransform<Self>
+    where
+        Self: Sized,
+    {
+        self.transform(Transform::from_matrix_unchecked(
+            nalgebra::Matrix4::new_translation(&translation.coords),
+        ))
+    }
+
+    /// exact
+    fn rotate(self, rotation: nalgebra::UnitQuaternion<FloatValue>) -> SdfTransform<Self>
+    where
+        Self: Sized,
+    {
+        self.transform(Transform::from_matrix_unchecked(rotation.to_homogeneous()))
+    }
+
+    /// exact
+    fn scale(self, scale: FloatValue) -> SdfScale<3, Self>
+    where
+        Self: Sized,
+    {
+        SdfScale::new(self, scale)
+    }
+
+    /// exact
+    ///
+    /// For carving interiors or giving thickness to primitives,
+    /// without performing expensive boolean operations
+    /// and without distorting the distance field into a bound,
+    /// one can use "onioning".
+    /// You can use it multiple times to create concentric layers in your SDF.
+    fn onion(self, thickness: FloatValue) -> SdfOnion<Self>
+    where
+        Self: Sized,
+    {
+        SdfOnion::new(self, thickness)
+    }
+}
+
+impl<T: Sdf<3>> Sdf3dModifiers for T {}

bampy/src/slicer/slice_path.rs

@@ -0,0 +1,151 @@
+use std::ops::RangeInclusive;
+
+use approx::relative_eq;
+use bvh::aabb::Aabb;
+use nalgebra::Point3;
+
+use super::{axis::Axis, mesh::Mesh, FloatValue};
+
+#[derive(Debug)]
+pub struct SlicePath {
+    pub i: usize,
+    pub d: FloatValue,
+    pub axis: Axis,
+    /// The points of the ring, in clockwise order.
+    pub points: Vec<Point3<FloatValue>>,
+    pub closed: bool,
+    pub aabb: Aabb<FloatValue, 3>,
+}
+
+pub struct SurfacePath {
+    pub i: RangeInclusive<usize>,
+    pub d: RangeInclusive<FloatValue>,
+    pub axis: Axis,
+    pub path: Vec<Point3<FloatValue>>,
+    pub aabb: Aabb<FloatValue, 3>,
+}
+
+pub struct SurfacePathIterator {
+    slices: Vec<Vec<SlicePath>>,
+    axis: Axis,
+    nozzle_width: FloatValue,
+}
+
+impl SurfacePathIterator {
+    pub fn new(mesh: &Mesh, axis: Axis, nozzle_width: FloatValue) -> Self {
+        let (h_axis, _) = axis.other();
+
+        Self {
+            slices: mesh
+                .slice_paths(axis, nozzle_width)
+                .map(|mut slice| {
+                    for ring in &mut slice {
+                        ring.points.sort_unstable_by(|a, b| {
+                            a.coords[h_axis as usize]
+                                .partial_cmp(&b.coords[h_axis as usize])
+                                .unwrap()
+                        })
+                    }
+                    slice.sort_unstable_by(|a, b| {
+                        a.points.first().unwrap().coords[h_axis as usize]
+                            .partial_cmp(&b.points.first().unwrap().coords[h_axis as usize])
+                            .unwrap()
+                    });
+                    let mut iter = slice.into_iter();
+                    let mut out = vec![iter.next().unwrap()];
+                    for ring in iter {
+                        if relative_eq!(
+                            out.last().unwrap().points.last().unwrap(),
+                            ring.points.first().unwrap(),
+                            epsilon = nozzle_width
+                        ) {
+                            let element = out.last_mut().unwrap();
+                            element.points.extend(ring.points);
+                            element.aabb.join_mut(&ring.aabb);
+                        } else {
+                            out.push(ring);
+                        }
+                    }
+                    out
+                })
+                .collect(),
+            axis,
+            nozzle_width,
+        }
+    }
+}
+
+impl Iterator for SurfacePathIterator {
+    type Item = SurfacePath;
+
+    fn next(&mut self) -> Option<Self::Item> {
+        self.slices.retain_mut(|slice| !slice.is_empty());
+
+        let (h_axis, _) = self.axis.other();
+
+        let ring = self.slices.first_mut()?.pop()?;
+        let mut item = Self::Item {
+            i: ring.i..=ring.i,
+            d: ring.d..=ring.d,
+            axis: ring.axis,
+            aabb: ring.aabb,
+            path: ring.points,
+        };
+
+        for slice in self.slices.iter_mut().skip(1) {
+            if *item.i.end() != slice[0].i - 1 {
+                break;
+            }
+
+            let last = item.path.last().unwrap();
+
+            let mut d = FloatValue::MAX;
+            let mut needs_reverse = false;
+            let mut index = None;
+
+            for (i, ring) in slice.iter().enumerate() {
+                macro_rules! item {
+                    ($a:ident, $metric: ident) => {
+                        $a.aabb.$metric[h_axis as usize]
+                    };
+                }
+                let a = item!(ring, max);
+                let b = item!(item, min);
+                if !(a > b || relative_eq!(a, b, epsilon = 0.1)) {
+                    continue;
+                }
+
+                let a = item!(ring, min);
+                let b = item!(item, max);
+                if !(a < b || relative_eq!(a, b, epsilon = 0.1)) {
+                    continue;
+                }
+
+                let d_left = last
+                    .coords
+                    .metric_distance(&ring.points.first().unwrap().coords);
+                let d_right = last
+                    .coords
+                    .metric_distance(&ring.points.last().unwrap().coords);
+                let d_min = d_left.min(d_right);
+                if d_min < d {
+                    d = d_min;
+                    needs_reverse = d_left > d_right;
+                    index = Some(i);
+                }
+            }
+
+            if let Some(mut ring) = index.map(|i| slice.remove(i)) {
+                if needs_reverse {
+                    ring.points.reverse();
+                }
+                item.i = *item.i.start()..=ring.i;
+                item.d = *item.d.start()..=ring.d;
+                item.path.append(&mut ring.points);
+                item.aabb.join_mut(&ring.aabb)
+            }
+        }
+
+        Some(item)
+    }
+}

bampy/src/slicer/slice_rings.rs

@@ -1,99 +0,0 @@
-use approx::relative_eq;
-use nalgebra::Vector3;
-
-use crate::console_log;
-
-use super::{
-    base_slices::{create_base_slices, BaseSlice},
-    mesh::Mesh,
-    FloatValue, SlicerOptions,
-};
-
-#[derive(Debug)]
-pub struct SliceRing {
-    pub d: FloatValue,
-    /// The points of the ring, in clockwise order.
-    pub points: Vec<Vector3<FloatValue>>,
-    pub closed: bool,
-}
-
-pub fn slice_rings<'a>(
-    axis: usize,
-    options: &'a SlicerOptions,
-    slicable: &'a Mesh,
-) -> impl Iterator<Item = Vec<SliceRing>> + 'a {
-    let mut layer_index = 0;
-    create_base_slices(axis, options, slicable)
-        .map(move |slice| find_slice_rings(axis, slice, &mut layer_index))
-}
-
-pub fn find_slice_rings(
-    axis: usize,
-    mut slice: BaseSlice,
-    layer_index: &mut u32,
-) -> Vec<SliceRing> {
-    let axis_a = (axis + 1) % 3;
-    let axis_b = (axis + 2) % 3;
-    let mut rings = vec![];
-    while let Some(line) = slice.lines.pop() {
-        if relative_eq!(line.start, line.end) {
-            continue;
-        }
-        let mut right = vec![line.end];
-        let mut left = vec![line.start];
-        let mut previous_len = usize::MAX;
-        let mut closed = false;
-
-        while !closed {
-            if previous_len == slice.lines.len() {
-                break;
-            }
-            previous_len = slice.lines.len();
-
-            slice.lines.retain_mut(|line| {
-                if closed {
-                    return true;
-                }
-
-                let test = |side: &mut Vec<Vector3<FloatValue>>| {
-                    let last = side.last().unwrap();
-                    let s = relative_eq!(line.start, last);
-                    let e = relative_eq!(line.end, last);
-                    if s && !e {
-                        side.push(line.end);
-                    } else if !s && e {
-                        side.push(line.start);
-                    }
-                    s || e
-                };
-
-                if test(&mut left) || test(&mut right) {
-                    closed = relative_eq!(left.last().unwrap(), right.last().unwrap());
-                    false
-                } else {
-                    true
-                }
-            })
-        }
-
-        left.reverse();
-        left.extend(right);
-        let mut ring = SliceRing {
-            d: slice.d,
-            closed,
-            points: left,
-        };
-
-        if ring.points.windows(2).fold(0.0, |acc, curr| {
-            acc + (curr[1][axis_a] - curr[0][axis_a]) * (curr[1][axis_b] + curr[0][axis_b])
-        }) < 0.0
-        {
-            ring.points.reverse();
-        }
-
-        rings.push(ring);
-        *layer_index += 1;
-    }
-
-    rings
-}

bampy/src/slicer/split_surface.rs

@@ -2,6 +2,7 @@ use super::{mesh::Mesh, triangle::Triangle};
 use bvh::bvh::{Bvh, BvhNode};
 
 /// Splits a surface into connected surfaces.
+/// TODO: self intersections
 pub fn split_surface(mut triangles: Vec<Triangle>) -> Vec<Mesh> {
     let mut surfaces = vec![];
     while let Some(triangle) = triangles.pop() {

bampy/src/slicer/trace_surface.rs

@@ -1,8 +1,8 @@
 use bvh::bvh::BvhNode;
 
-use super::{mesh::Mesh, slice_rings::SliceRing, z_projection::ToolpathIntersects, FloatValue};
+use super::{mesh::Mesh, slice_path::SlicePath, z_projection::ToolpathIntersects, FloatValue};
 
-pub fn trace_surface(slice: &mut SliceRing, surface: &Mesh, a: FloatValue) {
+pub fn trace_surface(slice: &mut SlicePath, surface: &Mesh, a: FloatValue) {
     slice.points.retain_mut(|point| {
         let mut stack = Vec::<usize>::new();
         stack.push(0);

bampy/src/slicer/triangle.rs

@@ -9,72 +9,50 @@ use super::{line::Line3, FloatValue};
 
 #[derive(Debug, Clone, Copy)]
 pub struct Triangle {
-    pub a: Vector3<FloatValue>,
-    pub b: Vector3<FloatValue>,
-    pub c: Vector3<FloatValue>,
+    pub a: Point3<FloatValue>,
+    pub b: Point3<FloatValue>,
+    pub c: Point3<FloatValue>,
     pub normal: Vector3<FloatValue>,
     node_index: usize,
     pub aabb: Aabb<FloatValue, 3>,
 }
 
-#[inline(always)]
-fn vec_inside_aabb(vec: &Vector3<FloatValue>, aabb: &Aabb<FloatValue, 3>) -> bool {
-    macro_rules! within {
-        ($axis:ident) => {
-            ((vec.$axis >= aabb.min.$axis && vec.$axis <= aabb.max.$axis)
-                || relative_eq!(vec.$axis, aabb.min.$axis)
-                || relative_eq!(vec.$axis, aabb.max.$axis))
-        };
-    }
-    within!(x) && within!(y) && within!(z)
-}
-
 impl Triangle {
-    pub fn new(a: Vector3<FloatValue>, b: Vector3<FloatValue>, c: Vector3<FloatValue>) -> Self {
+    pub fn new(a: Point3<FloatValue>, b: Point3<FloatValue>, c: Point3<FloatValue>) -> Self {
+        let mut aabb = a.aabb();
+        aabb.grow_mut(&b);
+        aabb.grow_mut(&c);
         Self {
             a,
             b,
             c,
             normal: (b - a).cross(&(c - a)).into(),
             node_index: 0,
-            aabb: Aabb::with_bounds(
-                Point3::new(
-                    FloatValue::min(FloatValue::max(a.x, b.x), c.x),
-                    FloatValue::min(FloatValue::min(a.y, b.y), c.y),
-                    FloatValue::min(FloatValue::min(a.z, b.z), c.z),
-                ),
-                Point3::new(
-                    FloatValue::max(FloatValue::max(a.x, b.x), c.x),
-                    FloatValue::max(FloatValue::max(a.y, b.y), c.y),
-                    FloatValue::max(FloatValue::max(a.z, b.z), c.z),
-                ),
-            ),
+            aabb,
         }
     }
 
     pub fn has_point_in_aabb(&self, aabb: &Aabb<FloatValue, 3>) -> bool {
-        vec_inside_aabb(&self.a, aabb)
-            || vec_inside_aabb(&self.b, aabb)
-            || vec_inside_aabb(&self.c, aabb)
+        aabb.contains(&self.a) || aabb.contains(&self.b) || aabb.contains(&self.c)
     }
 
-    pub fn has_vec(&self, vec: Vector3<FloatValue>) -> bool {
+    pub fn has_point(&self, vec: Point3<FloatValue>) -> bool {
         relative_eq!(self.a, vec) || relative_eq!(self.b, vec) || relative_eq!(self.c, vec)
     }
 
     pub fn shares_point_with_triangle(&self, other: Triangle) -> bool {
-        self.has_vec(other.a) || self.has_vec(other.b) || self.has_vec(other.c)
+        self.has_point(other.a) || self.has_point(other.b) || self.has_point(other.c)
     }
 
     pub fn shares_edge_with_triangle(&self, other: Triangle) -> bool {
-        let a = self.has_vec(other.a);
-        let b = self.has_vec(other.b);
-        let c = self.has_vec(other.c);
+        let a = self.has_point(other.a);
+        let b = self.has_point(other.b);
+        let c = self.has_point(other.c);
         a && b || a && c || b && c
     }
 
     pub fn intersect(&self, value: FloatValue, axis: usize) -> Option<Line3> {
-        let mut intersection = Vec::<Vector3<FloatValue>>::with_capacity(3);
+        let mut intersection = Vec::<Point3<FloatValue>>::with_capacity(3);
         let mut last = &self.c;
         for point in [self.a, self.b, self.c].iter() {
             if relative_eq!(point[axis], value) {
@@ -103,6 +81,12 @@ impl Triangle {
             None
         }
     }
+
+    pub fn area(&self) -> FloatValue {
+        let ab = self.b - self.a;
+        let ac = self.c - self.a;
+        0.5 * ab.cross(&ac).norm()
+    }
 }
 
 impl Bounded<FloatValue, 3> for Triangle {

bampy/src/slicer/z_projection.rs

@@ -1,5 +1,5 @@
 use bvh::aabb::Aabb;
-use nalgebra::{Point2, Vector2, Vector3};
+use nalgebra::{Point2, Point3};
 
 use super::{triangle::Triangle, FloatValue};
 
@@ -11,7 +11,7 @@ pub trait ProjectToolpath<T> {
 pub trait ToolpathIntersects<T>: ProjectToolpath<T> {
     /// Checks if a hypothetical toolpath that draws the object could intersect
     /// with the given point, given the tangent of the angle of the toolhead
-    fn toolpath_intersects(&self, point: &Vector3<FloatValue>, a: FloatValue) -> bool;
+    fn toolpath_intersects(&self, point: &Point3<FloatValue>, a: FloatValue) -> bool;
 }
 
 pub trait ToolpathIntersection {
@@ -38,7 +38,7 @@ impl ProjectToolpath<Aabb<FloatValue, 2>> for Aabb<FloatValue, 3> {
 }
 
 impl ToolpathIntersects<Aabb<FloatValue, 2>> for Aabb<FloatValue, 3> {
-    fn toolpath_intersects(&self, point: &Vector3<FloatValue>, a: FloatValue) -> bool {
+    fn toolpath_intersects(&self, point: &Point3<FloatValue>, a: FloatValue) -> bool {
         if let Some(aabb) = self.project_toolpath_onto_z(point.z, a) {
             aabb.approx_contains_eps(&Point2::new(point.x, point.y), FloatValue::EPSILON)
         } else {
@@ -100,7 +100,7 @@ impl ProjectToolpath<Triangle2D> for Triangle {
 mod tests {
     use approx::assert_relative_eq;
     use bvh::aabb::Aabb;
-    use nalgebra::{Point3, Vector2, Vector3};
+    use nalgebra::{point, Point3};
 
     use crate::slicer::{triangle::Triangle, z_projection::ProjectToolpath, FloatValue};
 
@@ -129,9 +129,9 @@ mod tests {
     #[test]
     fn test_project_triangle_toolpath() {
         let triangle = Triangle::new(
-            Vector3::new(0.0, 0.0, 0.0),
-            Vector3::new(0.0, 1.5, 1.0),
-            Vector3::new(-0.6, -1.4, 0.2),
+            point![0.0, 0.0, 0.0],
+            point![0.0, 1.5, 1.0],
+            point![-0.6, -1.4, 0.2],
         );
         let a = FloatValue::to_radians(30.0).tan();