mirrored slider parsing from osu!lazer

src/control_point_iter.rs

@@ -45,7 +45,7 @@ pub(crate) enum ControlPoint {
     },
     Difficulty {
         time: f32,
-        speed_mult: f32,
+        slider_velocity: f32,
     },
 }
 
@@ -74,7 +74,10 @@ impl<'p> Iterator for ControlPointIter<'p> {
                 self.next_difficulty =
                     next_tuple!(self.difficulty_points, (time, speed_multiplier));
 
-                Some(ControlPoint::Difficulty { time, speed_mult })
+                Some(ControlPoint::Difficulty {
+                    time,
+                    slider_velocity: speed_mult,
+                })
             }
             (Some((time, beat_len)), None) => {
                 self.next_timing = next_tuple!(self.timing_points, (time, beat_len));

src/curve.rs

@@ -3,44 +3,16 @@
     all(feature = "osu", not(feature = "no_sliders_no_leniency"))
 ))]
 
-use std::{borrow::Cow, cmp::Ordering, convert::identity};
+use std::{borrow::Cow, cmp::Ordering, convert::identity, f32::consts::PI};
 
 use crate::{
     math_util,
-    parse::{PathType, Pos2},
+    parse::{PathControlPoint, PathType, Pos2},
 };
 
 const BEZIER_TOLERANCE: f32 = 0.25;
-const CATMULL_DETAIL: f32 = 50.0;
+const CATMULL_DETAIL: usize = 50;
-
+const CIRCULAR_ARC_TOLERANCE: f32 = 0.1;
-pub(crate) enum Points {
-    Single(Pos2),
-    Multi(Vec<Pos2>),
-}
-
-impl Points {
-    #[inline]
-    fn point_at_distance(&self, dist: f32) -> Pos2 {
-        match self {
-            Points::Multi(points) => math_util::point_at_distance(points, dist),
-            Points::Single(point) => *point,
-        }
-    }
-}
-
-pub(crate) enum Curve<'p> {
-    Bezier {
-        path: Vec<Pos2>,
-        lengths: Vec<f32>,
-    },
-    Catmull(Points),
-    Linear(&'p [Pos2]),
-    Perfect {
-        origin: Pos2,
-        center: Pos2,
-        radius: f32,
-    },
-}
 
 struct BezierBuffers {
     buf1: Vec<Pos2>,
@@ -58,7 +30,485 @@ impl BezierBuffers {
     }
 }
 
-impl<'p> Curve<'p> {
+// TODO: Remove Default when cleaned up
+#[derive(Default)]
+struct CircularArcProperties {
+    is_valid: bool,
+    theta_start: f32,
+    theta_range: f32,
+    direction: f32,
+    radius: f32,
+    centre: Pos2,
+}
+
+pub(crate) struct Curve {
+    path: Vec<Pos2>,
+    lengths: Vec<f32>,
+}
+
+impl Curve {
+    pub(crate) fn new(points: &[PathControlPoint], expected_len: f32) -> Self {
+        let mut path = Self::calculate_path(points);
+        let lengths = Self::calculate_length(points, &mut path, expected_len);
+
+        Self { path, lengths }
+    }
+
+    pub(crate) fn position_at(&self, progress: f32) -> Pos2 {
+        let d = self.progress_to_dist(progress);
+        let i = self.idx_of_dist(d);
+
+        self.interpolate_vertices(i, d)
+    }
+
+    fn progress_to_dist(&self, progress: f32) -> f32 {
+        progress.clamp(0.0, 1.0) * self.dist()
+    }
+
+    pub(crate) fn dist(&self) -> f32 {
+        self.lengths.last().copied().unwrap_or(0.0)
+    }
+
+    fn idx_of_dist(&self, d: f32) -> usize {
+        self.lengths
+            .binary_search_by(|len| len.partial_cmp(&d).unwrap_or(Ordering::Equal))
+            .map_or_else(identity, identity)
+    }
+
+    fn interpolate_vertices(&self, i: usize, d: f32) -> Pos2 {
+        if self.path.is_empty() {
+            return Pos2::zero();
+        }
+
+        if i == 0 {
+            return self.path[0];
+        } else if i >= self.path.len() {
+            return self.path[self.path.len() - 1];
+        }
+
+        let p0 = self.path[i - 1];
+        let p1 = self.path[i];
+
+        let d0 = self.lengths[i - 1];
+        let d1 = self.lengths[i];
+
+        // * Avoid division by an almost-zero number in case
+        // * two points are extremely close to each other
+        if (d0 - d1).abs() <= f32::EPSILON {
+            return p0;
+        }
+
+        let w = (d - d0) / (d1 - d0);
+
+        p0 + (p1 - p0) * w
+    }
+
+    fn calculate_path(points: &[PathControlPoint]) -> Vec<Pos2> {
+        if points.is_empty() {
+            return Vec::new();
+        }
+
+        let mut path = Vec::new();
+        let vertices: Vec<_> = points.iter().map(|p| p.pos).collect();
+        let mut start = 0;
+
+        for i in 0..points.len() {
+            if points[i].kind.is_none() && i < points.len() - 1 {
+                continue;
+            }
+
+            // * The current vertex ends the segment
+            let segment_vertices = &vertices[start..i + 1];
+            let segment_kind = points[start].kind.unwrap_or(PathType::Linear);
+
+            // TODO: push onto `path` directly?
+            let sub_path = Self::calculate_subpath(segment_vertices, segment_kind);
+
+            for t in sub_path {
+                if path.last().filter(|&l| l == &t).is_none() {
+                    path.push(t);
+                }
+            }
+
+            // * Start the new segment at the current vertex
+            start = i;
+        }
+
+        path
+    }
+
+    fn calculate_length(
+        points: &[PathControlPoint],
+        path: &mut Vec<Pos2>,
+        expected_len: f32,
+    ) -> Vec<f32> {
+        let mut calculated_len = 0.0;
+        let mut cumulative_len = vec![0.0];
+
+        for i in 0..path.len() - 1 {
+            let diff = path[i + 1] - path[i];
+            calculated_len += diff.length();
+            cumulative_len.push(calculated_len);
+        }
+
+        if (expected_len - calculated_len).abs() > f32::EPSILON {
+            // * In osu-stable, if the last two control points of a slider are equal, extension is not performed
+            let condition_opt = points
+                .len()
+                .checked_sub(2)
+                .and_then(|i| points.get(i..))
+                .filter(|suffix| suffix[0].pos == suffix[1].pos && expected_len > calculated_len);
+
+            if condition_opt.is_some() {
+                cumulative_len.push(calculated_len);
+
+                return cumulative_len;
+            }
+
+            // * The last length is always incorrect
+            cumulative_len.pop();
+
+            let mut path_end_idx = path.len() - 1;
+
+            if calculated_len > expected_len {
+                // * The path will be shortened further, in which case we should trim
+                // * any more unnecessary lengths and their associated path segments
+                while cumulative_len
+                    .last()
+                    .filter(|&l| *l > expected_len)
+                    .is_some()
+                {
+                    cumulative_len.pop();
+                    path.remove(path_end_idx);
+                    path_end_idx -= 1;
+                }
+            }
+
+            if path_end_idx == 0 {
+                // * The expected distance is negative or zero
+                // * Perhaps negative path lengths should be disallowed altogether
+                cumulative_len.push(0.0);
+
+                return cumulative_len;
+            }
+
+            // * The direction of the segment to shorten or lengthen
+            let dir = (path[path_end_idx] - path[path_end_idx - 1]).normalize();
+
+            path[path_end_idx] =
+                path[path_end_idx - 1] + dir * (expected_len - cumulative_len.last().unwrap());
+            cumulative_len.push(expected_len);
+        }
+
+        cumulative_len
+    }
+
+    fn calculate_subpath(sub_points: &[Pos2], kind: PathType) -> Vec<Pos2> {
+        match kind {
+            PathType::Bezier => Self::approximate_bezier(sub_points),
+            PathType::Catmull => Self::approximate_catmull(sub_points),
+            PathType::Linear => Self::approximate_linear(sub_points),
+            PathType::PerfectCurve => {
+                if let [a, b, c] = sub_points {
+                    let sub_path = Self::approximate_circular_arc(*a, *b, *c);
+
+                    if !sub_path.is_empty() {
+                        return sub_path;
+                    }
+                }
+
+                Self::approximate_bezier(sub_points)
+            }
+        }
+    }
+
+    fn approximate_bezier(points: &[Pos2]) -> Vec<Pos2> {
+        let mut path = Vec::new(); // TODO: argument?
+        let mut bufs = BezierBuffers::new(points.len()); // TODO: argument?
+
+        Self::approximate_bspline(&mut path, points, &mut bufs);
+
+        path
+    }
+
+    fn approximate_catmull(points: &[Pos2]) -> Vec<Pos2> {
+        // TODO: argument?
+        let mut result = Vec::with_capacity((points.len() - 1) * CATMULL_DETAIL * 2);
+
+        let catmull_detail = CATMULL_DETAIL as f32;
+
+        for i in 0..points.len() - 1 {
+            let v2 = points[i];
+
+            let v1 = i
+                .checked_sub(1)
+                .and_then(|i| points.get(i).copied())
+                .unwrap_or(v2);
+
+            let v3 = points.get(i + 1).copied().unwrap_or_else(|| v2 * 2.0 - v1);
+            let v4 = points.get(i + 2).copied().unwrap_or_else(|| v3 * 2.0 - v2);
+
+            for c in 0..CATMULL_DETAIL {
+                let p1 = Self::catmull_find_point(v1, v2, v3, v4, c as f32 / catmull_detail);
+                let p2 = Self::catmull_find_point(v1, v2, v3, v4, (c + 1) as f32 / catmull_detail);
+
+                result.push(p1);
+                result.push(p2);
+            }
+        }
+
+        result
+    }
+
+    fn approximate_linear(points: &[Pos2]) -> Vec<Pos2> {
+        points.to_owned()
+    }
+
+    fn approximate_circular_arc(a: Pos2, b: Pos2, c: Pos2) -> Vec<Pos2> {
+        let pr = Self::circular_arc_properties(a, b, c);
+
+        if !pr.is_valid {
+            return Self::approximate_bezier(&[a, b, c]);
+        }
+
+        // * We select the amount of points for the approximation by requiring the discrete curvature
+        // * to be smaller than the provided tolerance. The exact angle required to meet the tolerance
+        // * is: 2 * Math.Acos(1 - TOLERANCE / r)
+        // * The special case is required for extremely short sliders where the radius is smaller than
+        // * the tolerance. This is a pathological rather than a realistic case.
+        let amount_points = if 2.0 * pr.radius <= CIRCULAR_ARC_TOLERANCE {
+            2
+        } else {
+            let divisor = 2.0 * (1.0 - CIRCULAR_ARC_TOLERANCE / pr.radius).acos();
+
+            ((pr.theta_range / divisor).ceil() as usize).max(2)
+        };
+
+        // TODO: argument?
+        let mut output = Vec::with_capacity(amount_points);
+
+        for i in 0..amount_points {
+            let fract = i as f32 / (amount_points - 1) as f32;
+            let theta = pr.theta_start + pr.direction * fract * pr.theta_range;
+            let (sin, cos) = theta.sin_cos();
+            let origin = Pos2 { x: cos, y: sin };
+
+            output.push(pr.centre + origin * pr.radius);
+        }
+
+        output
+    }
+
+    fn approximate_bspline(result: &mut Vec<Pos2>, points: &[Pos2], bufs: &mut BezierBuffers) {
+        let p = points.len();
+
+        let mut to_flatten = Vec::new();
+        let mut free_bufs = Vec::with_capacity(1);
+
+        // In osu!lazer's code, `p` is always 0 so the first big `if` can be omitted
+
+        to_flatten.push(Cow::Borrowed(points));
+
+        // * "toFlatten" contains all the curves which are not yet approximated well enough.
+        // * We use a stack to emulate recursion without the risk of running into a stack overflow.
+        // * (More specifically, we iteratively and adaptively refine our curve with a
+        // * <a href="https://en.wikipedia.org/wiki/Depth-first_search">Depth-first search</a>
+        // * over the tree resulting from the subdivisions we make.)
+
+        let mut left_child = bufs.buf2.to_owned();
+
+        while let Some(mut parent) = to_flatten.pop() {
+            if Self::bezier_is_flat_enough(&parent) {
+                // * If the control points we currently operate on are sufficiently "flat", we use
+                // * an extension to De Casteljau's algorithm to obtain a piecewise-linear approximation
+                // * of the bezier curve represented by our control points, consisting of the same amount
+                // * of points as there are control points.
+                Self::bezier_approximate(&parent, result, bufs);
+                free_bufs.push(parent);
+
+                continue;
+            }
+
+            // * If we do not yet have a sufficiently "flat" (in other words, detailed) approximation we keep
+            // * subdividing the curve we are currently operating on.
+            let mut right_child = free_bufs
+                .pop()
+                .unwrap_or_else(|| Cow::Owned(vec![Pos2::zero(); p]));
+
+            Self::bezier_subdivide(
+                &parent,
+                &mut left_child,
+                right_child.to_mut(),
+                &mut bufs.buf1,
+            );
+
+            // * We re-use the buffer of the parent for one of the children, so that we save one allocation per iteration.
+            parent.to_mut().copy_from_slice(&left_child[..p]);
+
+            to_flatten.push(right_child);
+            to_flatten.push(parent);
+        }
+
+        result.push(points[p - 1]);
+    }
+
+    fn bezier_is_flat_enough(points: &[Pos2]) -> bool {
+        let limit = BEZIER_TOLERANCE * BEZIER_TOLERANCE * 4.0;
+
+        !points
+            .iter()
+            .zip(points.iter().skip(1))
+            .zip(points.iter().skip(2))
+            .any(|((&prev, &curr), &next)| (prev - curr * 2.0 + next).length_squared() > limit)
+    }
+
+    fn bezier_subdivide(points: &[Pos2], l: &mut [Pos2], r: &mut [Pos2], buf: &mut [Pos2]) {
+        let count = points.len();
+        let midpoints = buf;
+        midpoints[..count].copy_from_slice(&points[..count]);
+
+        for i in (1..count).rev() {
+            l[count - i - 1] = midpoints[0];
+            r[i] = midpoints[i];
+
+            for j in 0..i {
+                midpoints[j] = (midpoints[j] + midpoints[j + 1]) / 2.0;
+            }
+        }
+
+        l[count - 1] = midpoints[0];
+        r[0] = midpoints[0];
+    }
+
+    // * https://en.wikipedia.org/wiki/De_Casteljau%27s_algorithm
+    fn bezier_approximate(points: &[Pos2], output: &mut Vec<Pos2>, bufs: &mut BezierBuffers) {
+        let count = points.len();
+        let r = &mut bufs.buf1;
+        let l = &mut bufs.buf2;
+
+        Self::bezier_subdivide(points, l, r, &mut bufs.buf3);
+        l[count..2 * count - 1].copy_from_slice(&r[1..count]);
+        output.push(points[0]);
+
+        let new_points = l
+            .iter()
+            .skip(1)
+            .zip(l.iter().skip(2))
+            .zip(l.iter().skip(3))
+            .step_by(2)
+            .take(count.saturating_sub(2))
+            .map(|((&prev, &curr), &next)| (prev + curr * 2.0 + next) * 0.25);
+
+        output.extend(new_points);
+    }
+
+    fn catmull_find_point(v1: Pos2, v2: Pos2, v3: Pos2, v4: Pos2, t: f32) -> Pos2 {
+        let t2 = t * t;
+        let t3 = t * t * t;
+
+        let x = 0.5
+            * (2.0 * v2.x
+                + (-v1.x + v3.x) * t
+                + (2.0 * v1.x - 5.0 * v2.x + 4.0 * v3.x - v4.x) * t2
+                + (-v1.x + 3.0 * v2.x - 3.0 * v3.x + v4.x) * t3);
+
+        let y = 0.5
+            * (2.0 * v2.y
+                + (-v1.y + v3.y) * t
+                + (2.0 * v1.y - 5.0 * v2.y + 4.0 * v3.y - v4.y) * t2
+                + (-v1.y + 3.0 * v2.y - 3.0 * v3.y + v4.y) * t3);
+
+        Pos2 { x, y }
+    }
+
+    fn circular_arc_properties(a: Pos2, b: Pos2, c: Pos2) -> CircularArcProperties {
+        // * If we have a degenerate triangle where a side-length is almost zero,
+        // * then give up and fallback to a more numerically stable method.
+        if ((b.y - a.y) * (c.x - a.x) - (b.x - a.x) * (c.y - a.y)).abs() <= f32::EPSILON {
+            // * Implicitly sets `is_valid` to false
+            return CircularArcProperties::default();
+        }
+
+        let d = 2.0 * (a.x * (b - c).y + b.x * (c - a).y + c.x * (a - b).y);
+        let a_s_q = a.length_squared();
+        let b_s_q = b.length_squared();
+        let c_s_q = c.length_squared();
+
+        let centre = Pos2 {
+            x: (a_s_q * (b - c).y + b_s_q * (c - a).y + c_s_q * (a - b).y) / d,
+            y: ((c - b).x + b_s_q * (a - c).x + c_s_q * (b - a).x) / d,
+        };
+
+        let d_a = a - centre;
+        let d_c = c - centre;
+
+        let radius = d_a.length();
+
+        let theta_start = d_a.y.atan2(d_a.x);
+        let mut theta_end = d_c.y.atan2(d_c.x);
+
+        while theta_end < theta_start {
+            theta_end += 2.0 * PI;
+        }
+
+        let mut direction = 1.0;
+        let mut theta_range = theta_end - theta_start;
+
+        // * Decide in which direction to draw the circle,
+        // * depending on which side of AC B lies.
+        let mut ortho_a_to_c = c - a;
+
+        ortho_a_to_c = Pos2 {
+            x: ortho_a_to_c.y,
+            y: -ortho_a_to_c.x,
+        };
+
+        if ortho_a_to_c.dot(b - a) < 0.0 {
+            direction = -direction;
+            theta_range = 2.0 * PI - theta_range;
+        }
+
+        CircularArcProperties {
+            is_valid: true,
+            theta_start,
+            theta_range,
+            direction,
+            radius,
+            centre,
+        }
+    }
+}
+
+pub(crate) enum Points {
+    Single(Pos2),
+    Multi(Vec<Pos2>),
+}
+
+impl Points {
+    #[inline]
+    fn point_at_distance(&self, dist: f32) -> Pos2 {
+        match self {
+            Points::Multi(points) => math_util::point_at_distance(points, dist),
+            Points::Single(point) => *point,
+        }
+    }
+}
+
+pub(crate) enum Curve_<'p> {
+    Bezier {
+        path: Vec<Pos2>,
+        lengths: Vec<f32>,
+    },
+    Catmull(Points),
+    Linear(&'p [Pos2]),
+    Perfect {
+        origin: Pos2,
+        center: Pos2,
+        radius: f32,
+    },
+}
+
+impl<'p> Curve_<'p> {
     #[inline]
     pub(crate) fn new(points: &'p [Pos2], kind: PathType, expected_len: f32) -> Self {
         match kind {
@@ -80,7 +530,7 @@ impl<'p> Curve<'p> {
 
         if len == 1 {
             return Self::Bezier {
-                path: points.to_owned(),
+                path: points,
                 lengths: vec![0.0],
             };
         }
@@ -103,8 +553,7 @@ impl<'p> Curve<'p> {
 
         // Then calculated cumulative lenghts
         let mut calculated_len = 0.0;
-        let mut cumulative_len = Vec::new();
+        let mut cumulative_len = vec![0.0];
-        cumulative_len.push(0.0);
 
         for i in 0..path.len() - 1 {
             let diff = path[i + 1] - path[i];
@@ -280,7 +729,7 @@ impl<'p> Curve<'p> {
             return Self::Catmull(Points::Single(points[0]));
         }
 
-        let mut result = Vec::with_capacity((len as f32 * CATMULL_DETAIL * 2.0) as usize);
+        let mut result = Vec::with_capacity((len * CATMULL_DETAIL * 2) as usize);
 
         // Handle first iteration distinctly because of v1
         let v1 = points[0];
@@ -315,8 +764,10 @@ impl<'p> Curve<'p> {
         let y3 = 2.0 * v1.y - 5.0 * v2.y + 4.0 * v3.y - v4.y;
         let y4 = -v1.y + 3.0 * (v2.y - v3.y) + v4.y;
 
+        let catmull_detail = CATMULL_DETAIL as f32;
+
         loop {
-            let t1 = c / CATMULL_DETAIL;
+            let t1 = c / catmull_detail;
             let t2 = t1 * t1;
             let t3 = t2 * t1;
 
@@ -325,7 +776,7 @@ impl<'p> Curve<'p> {
                 y: 0.5 * (y1 + y2 * t1 + y3 * t2 + y4 * t3),
             });
 
-            let t1 = (c + 1.0) / CATMULL_DETAIL;
+            let t1 = (c + 1.0) / catmull_detail;
             let t2 = t1 * t1;
             let t3 = t2 * t1;
 
@@ -336,7 +787,7 @@ impl<'p> Curve<'p> {
 
             c += 1.0;
 
-            if c >= CATMULL_DETAIL {
+            if c >= catmull_detail {
                 return;
             }
         }

src/fruits/mod.rs

@@ -70,17 +70,17 @@ pub fn stars(
                 pixel_len,
                 repeats,
                 curve_points,
-                path_type,
             } => {
                 // HR business
-                last_pos
+                last_pos.replace(
-                    .replace(h.pos.x + curve_points[curve_points.len() - 1].x - curve_points[0].x);
+                    h.pos.x + curve_points[curve_points.len() - 1].pos.x - curve_points[0].pos.x,
+                );
                 *last_time = h.start_time;
 
                 // Responsible for timing point values
                 slider_state.update(h.start_time);
 
-                let mut tick_distance = 100.0 * map.sv / map.tick_rate;
+                let mut tick_distance = 100.0 * map.slider_mult / map.tick_rate;
 
                 if map.version >= 8 {
                     tick_distance /=
@@ -88,11 +88,11 @@ pub fn stars(
                 }
 
                 let duration = *repeats as f32 * slider_state.beat_len * pixel_len
-                    / (map.sv * slider_state.speed_mult)
+                    / (map.slider_mult * slider_state.speed_mult)
                     / 100.0;
 
                 // Build the curve w.r.t. the curve points
-                let curve = Curve::new(curve_points, *path_type, *pixel_len);
+                let curve = Curve::new(curve_points, *pixel_len);
 
                 let mut current_distance = tick_distance;
                 let time_add = duration * (tick_distance / (*pixel_len * *repeats as f32));
@@ -103,7 +103,8 @@ pub fn stars(
                 // Tick of the first span
                 if current_distance < target {
                     for tick_idx in 1.. {
-                        let pos = curve.point_at_distance(current_distance);
+                        let progress = current_distance / *pixel_len;
+                        let pos = curve.position_at(progress);
                         let time = h.start_time + time_add * tick_idx as f32;
                         ticks.push((pos, time));
                         current_distance += tick_distance;
@@ -129,7 +130,8 @@ pub fn stars(
                     for repeat_id in 1..*repeats {
                         let dist = (repeat_id % 2) as f32 * *pixel_len;
                         let time_offset = (duration / *repeats as f32) * repeat_id as f32;
-                        let pos = curve.point_at_distance(dist);
+                        let progress = dist / *pixel_len;
+                        let pos = curve.position_at(progress);
 
                         // Reverse tick
                         slider_objects.push((pos, h.start_time + time_offset));
@@ -148,8 +150,8 @@ pub fn stars(
                 }
 
                 // Slider tail
-                let dist_end = (*repeats % 2) as f32 * *pixel_len;
+                // let dist_end = (*repeats % 2) as f32 * *pixel_len;
-                let pos = curve.point_at_distance(dist_end);
+                let pos = curve.position_at(1.0); // TODO: what if reversing odd amount?
                 slider_objects.push((pos, h.start_time + duration));
 
                 fruits += 1 + *repeats;
@@ -301,17 +303,17 @@ pub fn strains(map: &Beatmap, mods: impl Mods) -> Strains {
                 pixel_len,
                 repeats,
                 curve_points,
-                path_type,
             } => {
                 // HR business
-                last_pos
+                last_pos.replace(
-                    .replace(h.pos.x + curve_points[curve_points.len() - 1].x - curve_points[0].x);
+                    h.pos.x + curve_points[curve_points.len() - 1].pos.x - curve_points[0].pos.x,
+                );
                 *last_time = h.start_time;
 
                 // Responsible for timing point values
                 slider_state.update(h.start_time);
 
-                let mut tick_distance = 100.0 * map.sv / map.tick_rate;
+                let mut tick_distance = 100.0 * map.slider_mult / map.tick_rate;
 
                 if map.version >= 8 {
                     tick_distance /=
@@ -319,11 +321,11 @@ pub fn strains(map: &Beatmap, mods: impl Mods) -> Strains {
                 }
 
                 let duration = *repeats as f32 * slider_state.beat_len * pixel_len
-                    / (map.sv * slider_state.speed_mult)
+                    / (map.slider_mult * slider_state.speed_mult)
                     / 100.0;
 
                 // Build the curve w.r.t. the curve points
-                let curve = Curve::new(curve_points, *path_type, *pixel_len);
+                let curve = Curve::new(curve_points, *pixel_len);
 
                 let mut current_distance = tick_distance;
                 let time_add = duration * (tick_distance / (*pixel_len * *repeats as f32));
@@ -334,7 +336,8 @@ pub fn strains(map: &Beatmap, mods: impl Mods) -> Strains {
                 // Tick of the first span
                 if current_distance < target {
                     for tick_idx in 1.. {
-                        let pos = curve.point_at_distance(current_distance);
+                        let progress = current_distance / *pixel_len;
+                        let pos = curve.position_at(progress);
                         let time = h.start_time + time_add * tick_idx as f32;
                         ticks.push((pos, time));
                         current_distance += tick_distance;
@@ -357,7 +360,8 @@ pub fn strains(map: &Beatmap, mods: impl Mods) -> Strains {
                     for repeat_id in 1..*repeats {
                         let dist = (repeat_id % 2) as f32 * *pixel_len;
                         let time_offset = (duration / *repeats as f32) * repeat_id as f32;
-                        let pos = curve.point_at_distance(dist);
+                        let progress = dist / *pixel_len;
+                        let pos = curve.position_at(progress);
 
                         // Reverse tick
                         slider_objects.push((pos, h.start_time + time_offset));
@@ -374,8 +378,8 @@ pub fn strains(map: &Beatmap, mods: impl Mods) -> Strains {
                 }
 
                 // Slider tail
-                let dist_end = (*repeats % 2) as f32 * *pixel_len;
+                // let dist_end = (*repeats % 2) as f32 * *pixel_len;
-                let pos = curve.point_at_distance(dist_end);
+                let pos = curve.position_at(1.0); // TODO: what if reversing odd amount?
                 slider_objects.push((pos, h.start_time + duration));
 
                 let iter = slider_objects.into_iter().map(CatchObject::new);

src/fruits/slider_state.rs

@@ -14,7 +14,10 @@ impl<'p> SliderState<'p> {
 
         let (beat_len, speed_mult) = match control_points.next() {
             Some(ControlPoint::Timing { beat_len, .. }) => (beat_len, 1.0),
-            Some(ControlPoint::Difficulty { speed_mult, .. }) => (1000.0, speed_mult),
+            Some(ControlPoint::Difficulty {
+                slider_velocity: speed_mult,
+                ..
+            }) => (1000.0, speed_mult),
             None => (1000.0, 1.0),
         };
 
@@ -34,7 +37,10 @@ impl<'p> SliderState<'p> {
                     self.beat_len = *beat_len;
                     self.speed_mult = 1.0;
                 }
-                ControlPoint::Difficulty { speed_mult, .. } => self.speed_mult = *speed_mult,
+                ControlPoint::Difficulty {
+                    slider_velocity: speed_mult,
+                    ..
+                } => self.speed_mult = *speed_mult,
             }
 
             self.next = self.control_points.next();

src/osu/versions/no_leniency/mod.rs

@@ -340,7 +340,7 @@ pub fn strains(map: &Beatmap, mods: impl Mods) -> Strains {
 
 #[test]
 fn custom_osu() {
-    let file = std::fs::File::open("E:Games/osu!/beatmaps/2753127_.osu").unwrap();
+    let file = std::fs::File::open("E:Games/osu!/beatmaps/2753127.osu").unwrap();
     // let file = std::fs::File::open("E:Games/osu!/beatmaps/2571051.osu").unwrap();
     let map = Beatmap::parse(file).unwrap();
 
@@ -350,6 +350,7 @@ fn custom_osu() {
     let iters = 500;
     let accum = start.elapsed();
 
+    // * Tiny benchmark
     // let mut accum = accum;
 
     // for _ in 0..iters {

src/osu/versions/no_leniency/osu_object.rs

@@ -8,6 +8,7 @@ use crate::{
 };
 
 const LEGACY_LAST_TICK_OFFSET: f32 = 36.0;
+const BASE_SCORING_DISTANCE: f32 = 100.0;
 
 pub(crate) struct OsuObject {
     pub(crate) time: f32,
@@ -47,7 +48,6 @@ impl OsuObject {
                 pixel_len,
                 repeats,
                 curve_points,
-                path_type,
             } => {
                 // Key values which are computed here
                 let mut lazy_end_pos = h.pos;
@@ -56,21 +56,26 @@ impl OsuObject {
                 // Responsible for timing point values
                 slider_state.update(h.start_time);
 
+                let span_count = (*repeats + 1) as f32;
+
                 let approx_follow_circle_radius = radius * 3.0;
-                let mut tick_distance = 100.0 * map.sv / map.tick_rate;
+                let mut tick_dist = 100.0 * map.slider_mult / map.tick_rate;
 
                 if map.version >= 8 {
-                    tick_distance /=
+                    tick_dist /=
-                        (100.0 / slider_state.speed_mult).max(10.0).min(1000.0) / 100.0;
+                        (100.0 / slider_state.slider_velocity).max(10.0).min(1000.0) / 100.0;
                 }
 
-                let duration = *repeats as f32 * slider_state.beat_len * pixel_len
-                    / (map.sv * slider_state.speed_mult)
-                    / 100.0;
-                let span_duration = duration / *repeats as f32;
-
                 // Build the curve w.r.t. the curve points
-                let curve = Curve::new(curve_points, *path_type, *pixel_len);
+                let curve = Curve::new(curve_points, *pixel_len);
+
+                let velocity =
+                    (BASE_SCORING_DISTANCE * map.slider_mult * slider_state.slider_velocity)
+                        / slider_state.beat_len;
+
+                let end_time = h.start_time + span_count * curve.dist() / velocity;
+                let duration = end_time - h.start_time;
+                let span_duration = duration / span_count;
 
                 // Called on each slider object except for the head.
                 // Increases combo and adjusts `end_pos` and `travel_dist`
@@ -86,25 +91,23 @@ impl OsuObject {
                         progress %= 1.0;
                     }
 
-                    let curr_dist = pixel_len * progress;
+                    let curr_pos = curve.position_at(progress);
-                    let curr_pos = curve.point_at_distance(curr_dist);
+                    let diff = h.pos + curr_pos - lazy_end_pos;
-
-                    let diff = curr_pos - lazy_end_pos;
                     let mut dist = diff.length();
 
                     if dist > approx_follow_circle_radius {
+                        // * The cursor would be outside the follow circle, we need to move it
                         dist -= approx_follow_circle_radius;
                         lazy_end_pos += diff.normalize() * dist;
-
                         travel_dist += dist;
                     }
                 };
 
-                let mut current_distance = tick_distance;
+                let mut current_distance = tick_dist;
-                let time_add = duration * (tick_distance / (pixel_len * *repeats as f32));
+                let time_add = duration * (tick_dist / (pixel_len * span_count));
 
-                let target = pixel_len - tick_distance / 8.0;
+                let target = pixel_len - tick_dist / 8.0;
-                ticks.reserve((target / tick_distance) as usize);
+                ticks.reserve((target / tick_dist) as usize);
 
                 // Tick of the first span
                 if current_distance < target {
@@ -112,7 +115,7 @@ impl OsuObject {
                         let time = h.start_time + time_add * tick_idx as f32;
                         compute_vertex(time);
                         ticks.push(time);
-                        current_distance += tick_distance;
+                        current_distance += tick_dist;
 
                         if current_distance >= target {
                             break;
@@ -146,7 +149,7 @@ impl OsuObject {
 
                 ticks.clear();
 
-                let end_pos = curve.point_at_distance(*pixel_len);
+                let end_pos = curve.position_at(1.0); // TODO: what if reversing odd amount?
                 travel_dist *= scaling_factor;
 
                 Self {

src/osu/versions/no_leniency/slider_state.rs

@@ -4,7 +4,7 @@ pub(crate) struct SliderState<'p> {
     control_points: ControlPointIter<'p>,
     next: Option<ControlPoint>,
     pub(crate) beat_len: f32,
-    pub(crate) speed_mult: f32,
+    pub(crate) slider_velocity: f32,
 }
 
 impl<'p> SliderState<'p> {
@@ -12,9 +12,12 @@ impl<'p> SliderState<'p> {
     pub(crate) fn new(map: &'p Beatmap) -> Self {
         let mut control_points = ControlPointIter::new(map);
 
-        let (beat_len, speed_mult) = match control_points.next() {
+        let (beat_len, slider_velocity) = match control_points.next() {
             Some(ControlPoint::Timing { beat_len, .. }) => (beat_len, 1.0),
-            Some(ControlPoint::Difficulty { speed_mult, .. }) => (1000.0, speed_mult),
+            Some(ControlPoint::Difficulty {
+                slider_velocity: speed_mult,
+                ..
+            }) => (1000.0, speed_mult),
             None => (1000.0, 1.0),
         };
 
@@ -22,7 +25,7 @@ impl<'p> SliderState<'p> {
             next: control_points.next(),
             control_points,
             beat_len,
-            speed_mult,
+            slider_velocity,
         }
     }
 
@@ -32,9 +35,12 @@ impl<'p> SliderState<'p> {
             match next {
                 ControlPoint::Timing { beat_len, .. } => {
                     self.beat_len = *beat_len;
-                    self.speed_mult = 1.0;
+                    self.slider_velocity = 1.0;
                 }
-                ControlPoint::Difficulty { speed_mult, .. } => self.speed_mult = *speed_mult,
+                ControlPoint::Difficulty {
+                    slider_velocity: speed_mult,
+                    ..
+                } => self.slider_velocity = *speed_mult,
             }
 
             self.next = self.control_points.next();
@@ -88,10 +94,10 @@ mod test {
 
         state.update(3.0);
         assert_eq!(state.beat_len, 20.0);
-        assert_eq!(state.speed_mult, 1.0);
+        assert_eq!(state.slider_velocity, 1.0);
 
         state.update(5.0);
         assert_eq!(state.beat_len, 30.0);
-        assert_eq!(state.speed_mult, 45.0);
+        assert_eq!(state.slider_velocity, 45.0);
     }
 }

src/parse/hitobject.rs

@@ -1,11 +1,9 @@
-use super::Pos2;
+use super::{PathControlPoint, Pos2};
 
 #[cfg(any(
     feature = "fruits",
     all(feature = "osu", not(feature = "no_sliders_no_leniency"))
 ))]
-use super::PathType;
-
 use std::cmp::Ordering;
 
 /// "Intermediate" hitobject created through parsing.
@@ -63,8 +61,7 @@ pub enum HitObjectKind {
     Slider {
         pixel_len: f32,
         repeats: usize,
-        curve_points: Vec<Pos2>,
+        curve_points: Vec<PathControlPoint>,
-        path_type: PathType,
     },
     #[cfg(not(any(
         feature = "fruits",

src/parse/mod.rs

@@ -1,8 +1,4 @@
-#[cfg(any(
+use crate::math_util::is_linear;
-    feature = "fruits",
-    all(feature = "osu", not(feature = "no_sliders_no_leniency"))
-))]
-use crate::math_util;
 
 mod attributes;
 mod control_point;
@@ -21,7 +17,6 @@ pub use pos2::Pos2;
 use sort::legacy_sort;
 
 use std::cmp::Ordering;
-use std::str::FromStr;
 
 #[cfg(not(any(feature = "async_std", feature = "async_tokio")))]
 use std::io::{BufRead, BufReader, Read};
@@ -32,30 +27,34 @@ use tokio::io::{AsyncBufReadExt, AsyncRead, BufReader};
 #[cfg(feature = "async_std")]
 use async_std::io::{prelude::BufReadExt, BufReader as AsyncBufReader, Read as AsyncRead};
 
-macro_rules! sort {
+fn sort_unstable<T: PartialOrd>(slice: &mut [T]) {
-    ($slice:expr) => {
+    slice.sort_unstable_by(|p1, p2| p1.partial_cmp(&p2).unwrap_or(Ordering::Equal));
-        $slice.sort_unstable_by(|p1, p2| p1.partial_cmp(&p2).unwrap_or(Ordering::Equal))
-    };
-
-    (stable $slice:expr) => {
-        $slice.sort_by(|p1, p2| p1.partial_cmp(&p2).unwrap_or(Ordering::Equal))
-    };
 }
 
-macro_rules! next_field {
+fn sort<T: PartialOrd>(slice: &mut [T]) {
-    ($opt:expr, $err:literal) => {
+    slice.sort_by(|p1, p2| p1.partial_cmp(&p2).unwrap_or(Ordering::Equal));
-        $opt.ok_or_else(|| ParseError::MissingField($err))?
-    };
 }
 
-macro_rules! validate_float {
+trait OptionExt<T> {
-    ($x:expr) => {{
+    fn next_field(self, field: &'static str) -> Result<T, ParseError>;
-        if $x.is_finite() {
+}
-            $x
+
-        } else {
+impl<T> OptionExt<T> for Option<T> {
-            return Err(ParseError::InvalidFloatingPoint);
+    fn next_field(self, field: &'static str) -> Result<T, ParseError> {
-        }
+        self.ok_or_else(|| ParseError::MissingField(field))
-    }};
+    }
+}
+
+trait F32Ext: Sized {
+    fn validate(self) -> Result<Self, ParseError>;
+}
+
+impl F32Ext for f32 {
+    fn validate(self) -> Result<Self, ParseError> {
+        self.is_finite()
+            .then(|| self)
+            .ok_or(ParseError::InvalidFloatingPoint)
+    }
 }
 
 macro_rules! line_prepare {
@@ -236,12 +235,12 @@ macro_rules! parse_difficulty_body {
             $buf.clear();
         }
 
-        $self.od = next_field!(od, "od");
+        $self.od = od.next_field("od")?;
-        $self.cs = next_field!(cs, "cs");
+        $self.cs = cs.next_field("cs")?;
-        $self.hp = next_field!(hp, "hp");
+        $self.hp = hp.next_field("hp")?;
         $self.ar = ar.unwrap_or($self.od);
-        $self.sv = next_field!(sv, "sv");
+        $self.slider_mult = sv.next_field("sv")?;
-        $self.tick_rate = next_field!(tick_rate, "sv");
+        $self.tick_rate = tick_rate.next_field("tick rate")?;
 
         Ok(empty)
     }};
@@ -312,14 +311,14 @@ macro_rules! parse_timingpoints_body {
 
             let mut split = line.split(',');
 
-            let time = next_field!(split.next(), "timing point time")
+            let time = split
+                .next()
+                .next_field("timing point time")?
                 .trim()
-                .parse::<f32>()?;
+                .parse::<f32>()?
-            validate_float!(time);
+                .validate()?;
 
-            let beat_len = next_field!(split.next(), "beat len")
+            let beat_len: f32 = split.next().next_field("beat len")?.trim().parse()?;
-                .trim()
-                .parse::<f32>()?;
 
             if beat_len < 0.0 {
                 let point = DifficultyPoint {
@@ -348,11 +347,11 @@ macro_rules! parse_timingpoints_body {
         }
 
         if unsorted_timings {
-            sort!($self.timing_points);
+            sort_unstable(&mut $self.timing_points);
         }
 
         if unsorted_difficulties {
-            sort!($self.difficulty_points);
+            sort_unstable(&mut $self.difficulty_points);
         }
 
         Ok(empty)
@@ -395,217 +394,217 @@ macro_rules! parse_timingpoints {
     };
 }
 
-macro_rules! parse_hitobjects_body {
+// macro_rules! parse_hitobjects_body {
-    ($self:ident, $reader:ident, $buf:ident, $section:ident) => {{
+//     ($self:ident, $reader:ident, $buf:ident, $section:ident) => {{
-        let mut unsorted = false;
+//         let mut unsorted = false;
-        let mut prev_time = 0.0;
+//         let mut prev_time = 0.0;
 
-        let mut empty = true;
+//         let mut empty = true;
 
-        while read_line!($reader, $buf)? != 0 {
+//         while read_line!($reader, $buf)? != 0 {
-            let line = line_prepare!($buf);
+//             let line = line_prepare!($buf);
 
-            if line.starts_with('[') && line.ends_with(']') {
+//             if line.starts_with('[') && line.ends_with(']') {
-                *$section = Section::from_str(&line[1..line.len() - 1]);
+//                 *$section = Section::from_str(&line[1..line.len() - 1]);
-                empty = false;
+//                 empty = false;
-                $buf.clear();
+//                 $buf.clear();
-                break;
+//                 break;
-            }
+//             }
 
-            let mut split = line.split(',');
+//             let mut split = line.split(',');
 
-            let pos = Pos2 {
+//             let pos = Pos2 {
-                x: next_field!(split.next(), "x position").parse()?,
+//                 x: next_field!(split.next(), "x position").parse()?,
-                y: next_field!(split.next(), "y position").parse()?,
+//                 y: next_field!(split.next(), "y position").parse()?,
-            };
+//             };
 
-            let time: f32 = next_field!(split.next(), "hitobject time")
+//             let time: f32 = next_field!(split.next(), "hitobject time")
-                .trim()
+//                 .trim()
-                .parse()?;
+//                 .parse()?;
 
-            validate_float!(time);
+//             validate_float!(time);
 
-            if !$self.hit_objects.is_empty() && time < prev_time {
+//             if !$self.hit_objects.is_empty() && time < prev_time {
-                unsorted = true;
+//                 unsorted = true;
-            }
+//             }
 
-            let kind: u8 = next_field!(split.next(), "hitobject kind").parse()?;
+//             let kind: u8 = next_field!(split.next(), "hitobject kind").parse()?;
-            let sound = split.next().map(str::parse).transpose()?.unwrap_or(0);
+//             let sound = split.next().map(str::parse).transpose()?.unwrap_or(0);
 
-            let kind = if kind & Self::CIRCLE_FLAG > 0 {
+//             let kind = if kind & Self::CIRCLE_FLAG > 0 {
-                $self.n_circles += 1;
+//                 $self.n_circles += 1;
 
-                HitObjectKind::Circle
+//                 HitObjectKind::Circle
-            } else if kind & Self::SLIDER_FLAG > 0 {
+//             } else if kind & Self::SLIDER_FLAG > 0 {
-                $self.n_sliders += 1;
+//                 $self.n_sliders += 1;
 
-                #[cfg(any(
+//                 #[cfg(any(
-                    feature = "fruits",
+//                     feature = "fruits",
-                    all(feature = "osu", not(feature = "no_sliders_no_leniency"))
+//                     all(feature = "osu", not(feature = "no_sliders_no_leniency"))
-                ))]
+//                 ))]
-                {
+//                 {
-                    let mut curve_points = Vec::with_capacity(4);
+//                     let mut curve_points = Vec::with_capacity(4);
-                    curve_points.push(pos);
+//                     curve_points.push(pos);
 
-                    let mut curve_point_iter = next_field!(split.next(), "curve points").split('|');
+//                     let mut curve_point_iter = next_field!(split.next(), "curve points").split('|');
 
-                    let mut repeats: usize = next_field!(split.next(), "repeats")
+//                     let mut repeats: usize = next_field!(split.next(), "repeats")
-                        .parse()?;
+//                         .parse()?;
 
-                    if repeats > 9000 {
+//                     if repeats > 9000 {
-                        return Err(ParseError::TooManyRepeats);
+//                         return Err(ParseError::TooManyRepeats);
-                    }
+//                     }
 
-                    // * osu-stable treated the first span of the slider
+//                     // * osu-stable treated the first span of the slider
-                    // * as a repeat, but no repeats are happening
+//                     // * as a repeat, but no repeats are happening
-                    repeats = repeats.saturating_sub(1);
+//                     repeats = repeats.saturating_sub(1);
 
-                    let mut path_type: PathType =
+//                     let mut path_type: PathType =
-                        next_field!(curve_point_iter.next(), "path kind").parse()?;
+//                         next_field!(curve_point_iter.next(), "path kind").parse()?;
 
-                    for pos in curve_point_iter {
+//                     for pos in curve_point_iter {
-                        let mut v = pos.split(':').map(str::parse);
+//                         let mut v = pos.split(':').map(str::parse);
 
-                        match (v.next(), v.next()) {
+//                         match (v.next(), v.next()) {
-                            (Some(Ok(x)), Some(Ok(y))) => curve_points.push(Pos2 { x, y }),
+//                             (Some(Ok(x)), Some(Ok(y))) => curve_points.push(Pos2 { x, y }),
-                            _ => return Err(ParseError::InvalidCurvePoints),
+//                             _ => return Err(ParseError::InvalidCurvePoints),
-                        }
+//                         }
-                    }
+//                     }
 
-                    match path_type {
+//                     match path_type {
-                        PathType::Linear if curve_points.len() % 2 == 0 => {
+//                         PathType::Linear if curve_points.len() % 2 == 0 => {
-                            // Assert that the points are of the form A|B|B|C|C|E
+//                             // Assert that the points are of the form A|B|B|C|C|E
-                            if math_util::valid_linear(&curve_points) {
+//                             if math_util::valid_linear(&curve_points) {
-                                for i in (2..curve_points.len() - 1).rev().step_by(2) {
+//                                 for i in (2..curve_points.len() - 1).rev().step_by(2) {
-                                    curve_points.remove(i);
+//                                     curve_points.remove(i);
-                                }
+//                                 }
-                            } else {
+//                             } else {
-                                path_type = PathType::Bezier;
+//                                 path_type = PathType::Bezier;
-                            }
+//                             }
-                        }
+//                         }
-                        PathType::PerfectCurve if curve_points.len() == 3 => {
+//                         PathType::PerfectCurve if curve_points.len() == 3 => {
-                            if math_util::is_linear(curve_points[0], curve_points[1], curve_points[2]) {
+//                             if math_util::is_linear(curve_points[0], curve_points[1], curve_points[2]) {
-                                path_type = PathType::Linear;
+//                                 path_type = PathType::Linear;
-                            }
+//                             }
-                        },
+//                         },
-                        PathType::Catmull => {},
+//                         PathType::Catmull => {},
-                        _ => path_type = PathType::Bezier,
+//                         _ => path_type = PathType::Bezier,
-                    };
+//                     };
 
-                    // Reduce amount of curvepoints but keep the elements evenly spaced.
+//                     // Reduce amount of curvepoints but keep the elements evenly spaced.
-                    // Necessary to handle maps like XNOR (2573164) which have
+//                     // Necessary to handle maps like XNOR (2573164) which have
-                    // tens of thousands of curvepoints more efficiently.
+//                     // tens of thousands of curvepoints more efficiently.
-                    while curve_points.len() > CURVE_POINT_THRESHOLD {
+//                     while curve_points.len() > CURVE_POINT_THRESHOLD {
-                        let last = curve_points[curve_points.len() - 1];
+//                         let last = curve_points[curve_points.len() - 1];
-                        let last_idx = (curve_points.len() - 1) / 2;
+//                         let last_idx = (curve_points.len() - 1) / 2;
 
-                        for i in 1..=last_idx {
+//                         for i in 1..=last_idx {
-                            curve_points.swap(i, 2 * i);
+//                             curve_points.swap(i, 2 * i);
-                        }
+//                         }
 
-                        curve_points[last_idx] = last;
+//                         curve_points[last_idx] = last;
-                        curve_points.truncate(last_idx + 1);
+//                         curve_points.truncate(last_idx + 1);
-                    }
+//                     }
 
-                    if curve_points.is_empty() {
+//                     if curve_points.is_empty() {
-                        HitObjectKind::Circle
+//                         HitObjectKind::Circle
-                    } else {
+//                     } else {
-                        // TODO: Should be Option<f32>?
+//                         // TODO: Should be Option<f32>?
-                        let pixel_len = next_field!(split.next(), "pixel len")
+//                         let pixel_len = next_field!(split.next(), "pixel len")
-                            .parse::<f32>()?
+//                             .parse::<f32>()?
-                            .max(0.0)
+//                             .max(0.0)
-                            .min(MAX_COORDINATE_VALUE);
+//                             .min(MAX_COORDINATE_VALUE);
 
-                        HitObjectKind::Slider {
+//                         HitObjectKind::Slider {
-                            repeats,
+//                             repeats,
-                            pixel_len,
+//                             pixel_len,
-                            curve_points,
+//                             curve_points,
-                            path_type,
+//                             path_type,
-                        }
+//                         }
-                    }
+//                     }
-                }
+//                 }
 
-                #[cfg(not(any(
+//                 #[cfg(not(any(
-                    feature = "fruits",
+//                     feature = "fruits",
-                    all(feature = "osu", not(feature = "no_sliders_no_leniency"))
+//                     all(feature = "osu", not(feature = "no_sliders_no_leniency"))
-                )))]
+//                 )))]
-                {
+//                 {
-                    let repeats = next_field!(split.nth(1), "repeats").parse::<usize>()?;
+//                     let repeats = next_field!(split.nth(1), "repeats").parse::<usize>()?;
-                    let len: f32 = next_field!(split.next(), "pixel len").parse()?;
+//                     let len: f32 = next_field!(split.next(), "pixel len").parse()?;
 
-                    HitObjectKind::Slider {
+//                     HitObjectKind::Slider {
-                        repeats,
+//                         repeats,
-                        pixel_len: len,
+//                         pixel_len: len,
-                    }
+//                     }
-                }
+//                 }
-            } else if kind & Self::SPINNER_FLAG > 0 {
+//             } else if kind & Self::SPINNER_FLAG > 0 {
-                $self.n_spinners += 1;
+//                 $self.n_spinners += 1;
-                let end_time = next_field!(split.next(), "spinner endtime").parse()?;
+//                 let end_time = next_field!(split.next(), "spinner endtime").parse()?;
 
-                HitObjectKind::Spinner { end_time }
+//                 HitObjectKind::Spinner { end_time }
-            } else if kind & Self::HOLD_FLAG > 0 {
+//             } else if kind & Self::HOLD_FLAG > 0 {
-                $self.n_sliders += 1;
+//                 $self.n_sliders += 1;
-                let mut end = time;
+//                 let mut end = time;
 
-                if let Some(next) = split.next() {
+//                 if let Some(next) = split.next() {
-                    end = end.max(next_field!(next.split(':').next(), "hold endtime").parse()?);
+//                     end = end.max(next_field!(next.split(':').next(), "hold endtime").parse()?);
-                }
+//                 }
 
-                HitObjectKind::Hold { end_time: end }
+//                 HitObjectKind::Hold { end_time: end }
-            } else {
+//             } else {
-                return Err(ParseError::UnknownHitObjectKind);
+//                 return Err(ParseError::UnknownHitObjectKind);
-            };
+//             };
 
-            $self.hit_objects.push(HitObject {
+//             $self.hit_objects.push(HitObject {
-                pos,
+//                 pos,
-                start_time: time,
+//                 start_time: time,
-                kind,
+//                 kind,
-                sound, // TODO: omit if not taiko?
+//                 sound, // TODO: omit if not taiko?
-            });
+//             });
 
-            prev_time = time;
+//             prev_time = time;
-            $buf.clear();
+//             $buf.clear();
-        }
+//         }
 
-        // BUG: If [General] section comes after [HitObjects] then the mode
+//         // BUG: If [General] section comes after [HitObjects] then the mode
-        // won't be set yet so mania objects won't be sorted properly
+//         // won't be set yet so mania objects won't be sorted properly
-        if $self.mode == GameMode::MNA {
+//         if $self.mode == GameMode::MNA {
-            // First a _stable_ sort by time
+//             // First a _stable_ sort by time
-            sort!(stable $self.hit_objects);
+//             sort!(stable $self.hit_objects);
 
-            // Then the legacy sort for correct position order
+//             // Then the legacy sort for correct position order
-            legacy_sort(&mut $self.hit_objects);
+//             legacy_sort(&mut $self.hit_objects);
-        } else if unsorted {
+//         } else if unsorted {
-            sort!($self.hit_objects);
+//             sort!($self.hit_objects);
-        }
+//         }
 
-        Ok(empty)
+//         Ok(empty)
-    }};
+//     }};
-}
+// }
 
-macro_rules! parse_hitobjects {
+// macro_rules! parse_hitobjects {
-    ($reader:ident<$inner:ident>) => {
+//     ($reader:ident<$inner:ident>) => {
-        fn parse_hitobjects<R: $inner>(
+//         fn parse_hitobjects<R: $inner>(
-            &mut self,
+//             &mut self,
-            reader: &mut $reader<R>,
+//             reader: &mut $reader<R>,
-            buf: &mut String,
+//             buf: &mut String,
-            section: &mut Section,
+//             section: &mut Section,
-        ) -> ParseResult<bool> {
+//         ) -> ParseResult<bool> {
-            parse_hitobjects_body!(self, reader, buf, section)
+//             parse_hitobjects_body!(self, reader, buf, section)
-        }
+//         }
-    };
+//     };
 
-    (async $reader:ident<$inner:ident>) => {
+//     (async $reader:ident<$inner:ident>) => {
-        async fn parse_hitobjects<R: $inner + Unpin>(
+//         async fn parse_hitobjects<R: $inner + Unpin>(
-            &mut self,
+//             &mut self,
-            reader: &mut $reader<R>,
+//             reader: &mut $reader<R>,
-            buf: &mut String,
+//             buf: &mut String,
-            section: &mut Section,
+//             section: &mut Section,
-        ) -> ParseResult<bool> {
+//         ) -> ParseResult<bool> {
-            parse_hitobjects_body!(self, reader, buf, section)
+//             parse_hitobjects_body!(self, reader, buf, section)
-        }
+//         }
-    };
+//     };
-}
+// }
 
 macro_rules! parse_body {
     ($reader:ident<$inner:ident>: $input:ident) => {{
@@ -711,7 +710,7 @@ pub struct Beatmap {
     pub od: f32,
     pub cs: f32,
     pub hp: f32,
-    pub sv: f32,
+    pub slider_mult: f32,
     pub tick_rate: f32,
     pub hit_objects: Vec<HitObject>,
 
@@ -727,12 +726,6 @@ pub struct Beatmap {
 
 pub(crate) const OSU_FILE_HEADER: &str = "osu file format v";
 
-#[cfg(any(
-    feature = "fruits",
-    all(feature = "osu", not(feature = "no_sliders_no_leniency"))
-))]
-const CURVE_POINT_THRESHOLD: usize = 256;
-
 #[cfg(any(
     feature = "fruits",
     all(feature = "osu", not(feature = "no_sliders_no_leniency"))
@@ -759,7 +752,310 @@ impl Beatmap {
     parse_general!(BufReader<Read>);
     parse_difficulty!(BufReader<Read>);
     parse_timingpoints!(BufReader<Read>);
-    parse_hitobjects!(BufReader<Read>);
+    // parse_hitobjects!(BufReader<Read>);
+
+    // TODO: Remove
+    fn parse_hitobjects<R: Read>(
+        &mut self,
+        reader: &mut BufReader<R>,
+        buf: &mut String,
+        section: &mut Section,
+    ) -> ParseResult<bool> {
+        // parse_hitobjects_body!(self, reader, buf, section)
+
+        let mut unsorted = false;
+        let mut prev_time = 0.0;
+
+        let mut empty = true;
+
+        while read_line!(reader, buf)? != 0 {
+            let line = line_prepare!(buf);
+
+            if line.starts_with('[') && line.ends_with(']') {
+                *section = Section::from_str(&line[1..line.len() - 1]);
+                empty = false;
+                buf.clear();
+                break;
+            }
+
+            let mut split = line.split(',');
+
+            let pos = Pos2 {
+                x: split.next().next_field("x pos")?.parse()?,
+                y: split.next().next_field("y pos")?.parse()?,
+            };
+
+            let time = split
+                .next()
+                .next_field("hitobject time")?
+                .trim()
+                .parse::<f32>()?
+                .validate()?;
+
+            if !self.hit_objects.is_empty() && time < prev_time {
+                unsorted = true;
+            }
+
+            let kind: u8 = split.next().next_field("hitobject kind")?.parse()?;
+            let sound = split.next().map(str::parse).transpose()?.unwrap_or(0);
+
+            let kind = if kind & Self::CIRCLE_FLAG > 0 {
+                self.n_circles += 1;
+
+                HitObjectKind::Circle
+            } else if kind & Self::SLIDER_FLAG > 0 {
+                self.n_sliders += 1;
+
+                #[cfg(any(
+                    feature = "fruits",
+                    all(feature = "osu", not(feature = "no_sliders_no_leniency"))
+                ))]
+                {
+                    let mut curve_points = Vec::with_capacity(4);
+                    curve_points.push(pos);
+
+                    let curve_point_iter = split.next().next_field("curve points")?.split("|");
+                    let mut repeats: usize = split.next().next_field("repeats")?.parse()?;
+
+                    if repeats > 9000 {
+                        return Err(ParseError::TooManyRepeats);
+                    }
+
+                    // * osu-stable treated the first span of the slider
+                    // * as a repeat, but no repeats are happening
+                    repeats = repeats.saturating_sub(1);
+
+                    let mut start_idx = 0;
+                    let mut end_idx = 0;
+                    let mut first = true;
+
+                    let point_split: Vec<_> = curve_point_iter.collect();
+                    let mut segments = Vec::new();
+
+                    while {
+                        end_idx += 1;
+
+                        end_idx < point_split.len()
+                    } {
+                        // * Keep incrementing end_idx while it's not the start of a new segment
+                        // * (indicated by having a type descriptor of length 1).
+                        if point_split[end_idx].len() > 1 {
+                            continue;
+                        }
+
+                        // * Multi-segmented sliders DON'T contain the end point as part of the
+                        // * current segment as it's assumed to be the start of the next segment.
+                        // * The start of the next segment is the index after the type descriptor.
+                        let end_point = point_split.get(end_idx + 1).copied();
+
+                        convert_points(
+                            &point_split[start_idx..end_idx],
+                            end_point,
+                            first,
+                            pos,
+                            &mut segments,
+                        )?;
+
+                        start_idx = end_idx;
+                        first = false;
+                    }
+
+                    if end_idx > start_idx {
+                        convert_points(
+                            &point_split[start_idx..end_idx],
+                            None,
+                            first,
+                            pos,
+                            &mut segments,
+                        )?;
+                    }
+
+                    let curve_points = merge_points_lists(segments);
+
+                    if curve_points.is_empty() {
+                        HitObjectKind::Circle
+                    } else {
+                        let pixel_len = split
+                            .next()
+                            .next_field("pixel len")?
+                            .parse::<f32>()?
+                            .max(0.0)
+                            .min(MAX_COORDINATE_VALUE);
+
+                        HitObjectKind::Slider {
+                            repeats,
+                            pixel_len,
+                            curve_points,
+                        }
+                    }
+                }
+
+                #[cfg(not(any(
+                    feature = "fruits",
+                    all(feature = "osu", not(feature = "no_sliders_no_leniency"))
+                )))]
+                {
+                    let repeats = next_field!(split.nth(1), "repeats").parse::<usize>()?;
+                    let len: f32 = next_field!(split.next(), "pixel len").parse()?;
+
+                    HitObjectKind::Slider {
+                        repeats,
+                        pixel_len: len,
+                    }
+                }
+            } else if kind & Self::SPINNER_FLAG > 0 {
+                self.n_spinners += 1;
+                let end_time = split.next().next_field("spinner endtime")?.parse()?;
+
+                HitObjectKind::Spinner { end_time }
+            } else if kind & Self::HOLD_FLAG > 0 {
+                self.n_sliders += 1;
+                let mut end = time;
+
+                if let Some(next) = split.next() {
+                    end = end.max(next.split(':').next().next_field("hold endtime")?.parse()?);
+                }
+
+                HitObjectKind::Hold { end_time: end }
+            } else {
+                return Err(ParseError::UnknownHitObjectKind);
+            };
+
+            self.hit_objects.push(HitObject {
+                pos,
+                start_time: time,
+                kind,
+                sound, // TODO: omit if not taiko?
+            });
+
+            prev_time = time;
+            buf.clear();
+        }
+
+        // BUG: If [General] section comes after [HitObjects] then the mode
+        // won't be set yet so mania objects won't be sorted properly
+        if self.mode == GameMode::MNA {
+            // First a _stable_ sort by time
+            sort(&mut self.hit_objects);
+
+            // Then the legacy sort for correct position order
+            legacy_sort(&mut self.hit_objects);
+        } else if unsorted {
+            sort_unstable(&mut self.hit_objects);
+        }
+
+        Ok(empty)
+    }
+}
+
+// TODO: Cleanup
+fn convert_points(
+    points: &[&str],
+    end_point: Option<&str>,
+    first: bool,
+    offset: Pos2,
+    segments: &mut Vec<Vec<PathControlPoint>>,
+) -> Result<(), ParseError> {
+    let mut path_kind = PathType::from_str(points[0]);
+
+    let read_offset = first as usize;
+    let readable_points = points.len() - 1;
+    let end_point_len = end_point.is_some() as usize;
+
+    let mut vertices =
+        vec![PathControlPoint::default(); read_offset + readable_points + end_point_len];
+
+    // * Fill any non-read points.
+    // Not necessary since vertices are already initialized
+
+    // * Parse into control points.
+    for i in 1..points.len() {
+        read_point(points[i], offset, &mut vertices[read_offset + i - 1])?;
+    }
+
+    // * If an endpoint is given, add it to the end.
+    if let Some(end_point) = end_point {
+        read_point(end_point, offset, vertices.last_mut().unwrap())?;
+    }
+
+    // * Edge-case rules (to match stable).
+    if path_kind == PathType::PerfectCurve {
+        if vertices.len() != 3 {
+            path_kind = PathType::Bezier;
+        } else if is_linear(vertices[0].pos, vertices[1].pos, vertices[2].pos) {
+            // * osu-stable special-cased colinear perfect curves to a linear path
+            path_kind = PathType::Linear;
+        }
+    }
+
+    // * The first control point must have a definite type.
+    vertices[0].kind = Some(path_kind);
+
+    // * A path can have multiple implicit segments of the same type if
+    // * there are two sequential control points with the same position.
+    // * To handle such cases, this code may return multiple path segments
+    // * with the final control point in each segment having a non-null type.
+    // * For the point string X|1:1|2:2|2:2|3:3, this code returns the segments:
+    // * X: { (1,1), (2, 2) }
+    // * X: { (3, 3) }
+    // * Note: (2, 2) is not returned in the second segments, as it is implicit in the path.
+    let mut start_idx = 0;
+    let mut end_idx = 0;
+
+    while {
+        end_idx += 1;
+
+        end_idx < vertices.len() - end_point_len
+    } {
+        // * Keep incrementing while an implicit segment doesn't need to be started
+        if vertices[end_idx].pos != vertices[end_idx - 1].pos {
+            continue;
+        }
+
+        // * The last control point of each segment is not
+        // * allowed to start a new implicit segment.
+        if end_idx == vertices.len() - end_point_len - 1 {
+            continue;
+        }
+
+        // * Force a type on the last point, and return
+        // * the current control point set as a segment.
+        vertices[end_idx - 1].kind = Some(path_kind);
+        segments.push(vertices[start_idx..end_idx].to_owned());
+
+        // * Skip the current control point - as it's the same as the one that's just been returned.
+        start_idx = end_idx + 1;
+    }
+
+    if end_idx > start_idx {
+        segments.push(vertices[start_idx..end_idx].to_owned());
+    }
+
+    Ok(())
+}
+
+fn read_point(
+    value: &str,
+    start_pos: Pos2,
+    point: &mut PathControlPoint,
+) -> Result<(), ParseError> {
+    let mut v = value.split(':').map(str::parse);
+
+    match (v.next(), v.next()) {
+        (Some(Ok(x)), Some(Ok(y))) => point.pos = Pos2 { x, y } - start_pos,
+        _ => return Err(ParseError::InvalidCurvePoints),
+    };
+
+    Ok(())
+}
+
+fn merge_points_lists(control_point_list: Vec<Vec<PathControlPoint>>) -> Vec<PathControlPoint> {
+    let total_count = control_point_list.iter().map(Vec::len).sum();
+    let mut merged_list = Vec::with_capacity(total_count);
+    let iter = control_point_list.into_iter().map(Vec::into_iter).flatten();
+    merged_list.extend(iter);
+
+    merged_list
 }
 
 #[cfg(feature = "async_tokio")]
@@ -787,6 +1083,12 @@ fn split_colon(line: &str) -> Option<(&str, &str)> {
     Some((split.next()?, split.next()?.trim()))
 }
 
+#[derive(Copy, Clone, Debug, Default, PartialEq)]
+pub struct PathControlPoint {
+    pub pos: Pos2,
+    pub kind: Option<PathType>,
+}
+
 /// The type of curve of a slider.
 #[derive(Copy, Clone, Debug, Eq, PartialEq)]
 pub enum PathType {
@@ -796,17 +1098,14 @@ pub enum PathType {
     PerfectCurve = 3,
 }
 
-impl FromStr for PathType {
+impl PathType {
-    type Err = ParseError;
-
     #[inline]
-    fn from_str(s: &str) -> Result<Self, Self::Err> {
+    fn from_str(s: &str) -> Self {
         match s {
-            "L" => Ok(Self::Linear),
+            "L" => Self::Linear,
-            "C" => Ok(Self::Catmull),
+            "B" => Self::Bezier,
-            "B" => Ok(Self::Bezier),
+            "P" => Self::PerfectCurve,
-            "P" => Ok(Self::PerfectCurve),
+            _ => Self::Catmull,
-            _ => Err(ParseError::InvalidPathType),
         }
     }
 }
@@ -928,7 +1227,7 @@ mod tests {
         println!("od: {}", map.od);
         println!("cs: {}", map.cs);
         println!("hp: {}", map.hp);
-        println!("sv: {}", map.sv);
+        println!("slider_mult: {}", map.slider_mult);
         println!("tick_rate: {}", map.tick_rate);
         println!("hit_objects: {}", map.hit_objects.len());