Auto merge of #9635 - nox:mv-bezier, r=jdm

Move util::bezier to style

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components/util/bezier.rs

@@ -1,115 +0,0 @@
-/* This Source Code Form is subject to the terms of the Mozilla Public
- * License, v. 2.0. If a copy of the MPL was not distributed with this
- * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
-
-//! Parametric Bézier curves.
-//!
-//! This is based on `WebCore/platform/graphics/UnitBezier.h` in WebKit.
-
-use euclid::point::Point2D;
-
-const NEWTON_METHOD_ITERATIONS: u8 = 8;
-
-pub struct Bezier {
-    ax: f64,
-    bx: f64,
-    cx: f64,
-    ay: f64,
-    by: f64,
-    cy: f64,
-}
-
-impl Bezier {
-    #[inline]
-    pub fn new(p1: Point2D<f64>, p2: Point2D<f64>) -> Bezier {
-        let cx = 3.0 * p1.x;
-        let bx = 3.0 * (p2.x - p1.x) - cx;
-
-        let cy = 3.0 * p1.y;
-        let by = 3.0 * (p2.y - p1.y) - cy;
-
-        Bezier {
-            ax: 1.0 - cx - bx,
-            bx: bx,
-            cx: cx,
-            ay: 1.0 - cy - by,
-            by: by,
-            cy: cy,
-        }
-    }
-
-    #[inline]
-    fn sample_curve_x(&self, t: f64) -> f64 {
-        // ax * t^3 + bx * t^2 + cx * t
-        ((self.ax * t + self.bx) * t + self.cx) * t
-    }
-
-    #[inline]
-    fn sample_curve_y(&self, t: f64) -> f64 {
-        ((self.ay * t + self.by) * t + self.cy) * t
-    }
-
-    #[inline]
-    fn sample_curve_derivative_x(&self, t: f64) -> f64 {
-        (3.0 * self.ax * t + 2.0 * self.bx) * t + self.cx
-    }
-
-    #[inline]
-    fn solve_curve_x(&self, x: f64, epsilon: f64) -> f64 {
-        // Fast path: Use Newton's method.
-        let mut t = x;
-        for _ in 0..NEWTON_METHOD_ITERATIONS {
-            let x2 = self.sample_curve_x(t);
-            if x2.approx_eq(x, epsilon) {
-                return t
-            }
-            let dx = self.sample_curve_derivative_x(t);
-            if dx.approx_eq(0.0, 1e-6) {
-                break
-            }
-            t -= (x2 - x) / dx;
-        }
-
-        // Slow path: Use bisection.
-        let (mut lo, mut hi, mut t) = (0.0, 1.0, x);
-
-        if t < lo {
-            return lo
-        }
-        if t > hi {
-            return hi
-        }
-
-        while lo < hi {
-            let x2 = self.sample_curve_x(t);
-            if x2.approx_eq(x, epsilon) {
-                return t
-            }
-            if x > x2 {
-                lo = t
-            } else {
-                hi = t
-            }
-            t = (hi - lo) / 2.0 + lo
-        }
-
-        t
-    }
-
-    #[inline]
-    pub fn solve(&self, x: f64, epsilon: f64) -> f64 {
-        self.sample_curve_y(self.solve_curve_x(x, epsilon))
-    }
-}
-
-trait ApproxEq {
-    fn approx_eq(self, value: Self, epsilon: Self) -> bool;
-}
-
-impl ApproxEq for f64 {
-    #[inline]
-    fn approx_eq(self, value: f64, epsilon: f64) -> bool {
-        (self - value).abs() < epsilon
-    }
-}
-

components/util/lib.rs

@@ -49,7 +49,6 @@ extern crate uuid;
 
 use std::sync::Arc;
 
-pub mod bezier;
 pub mod cache;
 pub mod cursor;
 pub mod debug_utils;