max/splines
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Refactor polymorphic sampling code.

Browse Source
This commit is contained in:
Dimitri Sabadie
2019-04-17 14:16:42 +02:00
parent 48623701a7
commit 5b70d6921c
4 changed files with 93 additions and 179 deletions
Download Patch File Download Diff File Expand all files Collapse all files

27
Cargo.toml
View File

@@ -20,28 +20,13 @@ is-it-maintained-open-issues = { repository = "phaazon/splines" }
maintenance = { status = "actively-developed" }
[features]
default = ["std", "impl-cgmath"]
default = ["std"]
serialization = ["serde", "serde_derive"]
std = ["num-traits/std"]
impl-cgmath = ["cgmath"]
impl-nalgebra = ["nalgebra"]
[dependencies.nalgebra]
version = ">=0.14, <0.17"
optional = true
[dependencies.cgmath]
version = "0.16"
optional = true
[dependencies.num-traits]
num-traits = "0.2"
default-features = false
[dependencies.serde]
version = "1"
optional = true
[dependencies.serde_derive]
version = "1"
optional = true
[dependencies]
nalgebra = { version = ">=0.14, <0.19", optional = true }
num-traits = { version = "0.2", default-features = false }
serde = { version = "1", optional = true }
serde_derive = { version = "1", optional = true }

4
examples/02-serialization/src/main.rs
View File

@@ -1,7 +1,7 @@
#[macro_use] extern crate serde_json;
extern crate splines;
use serde_json::{Value, from_value};
use serde_json::from_value;
use splines::Spline;
fn main() {
@@ -25,6 +25,6 @@ fn main() {
]
};
let spline = from_value::<Spline<f32>>(value);
let spline = from_value::<Spline<f32, f32>>(value);
println!("{:?}", spline);
}

230
src/lib.rs
View File

@@ -81,9 +81,6 @@
//! + This feature implements both the `Serialize` and `Deserialize` traits from `serde` for all
//! types exported by this crate.
//! + Enable with the `"serialization"` feature.
//! - **[cgmath](https://crates.io/crates/cgmath) implementors.**
//! + Adds some useful implementations of `Interpolate` for some cgmath types.
//! + Enable with the `"impl-cgmath"` feature.
//! - **[nalgebra](https://crates.io/crates/nalgebra) implementors.**
//! + Adds some useful implementations of `Interpolate` for some nalgebra types.
//! + Enable with the `"impl-nalgebra"` feature.
@@ -97,27 +94,12 @@
#![cfg_attr(not(feature = "std"), feature(alloc))]
#![cfg_attr(not(feature = "std"), feature(core_intrinsics))]
// on no_std, we also need the alloc crate for Vec
#[cfg(not(feature = "std"))] extern crate alloc;
#[cfg(feature = "impl-cgmath")] extern crate cgmath;
#[cfg(feature = "impl-nalgebra")] extern crate nalgebra;
#[cfg(feature = "serialization")] extern crate serde;
#[cfg(feature = "serialization")] #[macro_use] extern crate serde_derive;
#[cfg(feature = "impl-cgmath")]
use cgmath::{
BaseFloat, InnerSpace, Quaternion, Vector2, Vector3, Vector4
};
#[cfg(feature = "impl-nalgebra")] use nalgebra as na;
#[cfg(feature = "impl-nalgebra")] use nalgebra::core::{DimName, DefaultAllocator, Scalar};
#[cfg(feature = "impl-nalgebra")] use nalgebra::core::allocator::Allocator;
#[cfg(feature = "std")] use std::cmp::Ordering;
#[cfg(feature = "std")] use std::ops::{Add, Div, Mul, Sub};
#[cfg(feature = "std")] use std::ops::{Div, Mul};
#[cfg(feature = "serialization")] use serde_derive::{Deserialize, Serialize};
#[cfg(not(feature = "std"))] use alloc::vec::Vec;
#[cfg(not(feature = "std"))] use core::cmp::Ordering;
@@ -217,11 +199,11 @@ impl<T, V> Spline<T, V> {
/// # Return
///
/// `None` if you try to sample a value at a time that has no key associated with. That can also
/// happen if you try to sample between two keys with a specific interpolation mode that make the
/// happen if you try to sample between two keys with a specific interpolation mode that makes the
/// sampling impossible. For instance, `Interpolate::CatmullRom` requires *four* keys. If you’re
/// near the beginning of the spline or its end, ensure you have enough keys around to make the
/// sampling.
pub fn sample(&self, t: T) -> Option<V> where V: Interpolate<T>, T: Float {
pub fn sample(&self, t: T) -> Option<V> where T: Float + FloatConst, V: Interpolate<T> {
let keys = &self.0;
let i = search_lower_cp(keys, t)?;
let cp0 = &keys[i];
@@ -241,9 +223,10 @@ impl<T, V> Spline<T, V> {
}
Interpolation::Cosine => {
let two_t = T::one() + T::one();
let cp1 = &keys[i+1];
let nt = normalize_time(t, cp0, cp1);
let cos_nt = (1. - (nt * T::PI).cos()) * 0.5;
let cos_nt = (T::one() - (nt * T::PI()).cos()) / two_t;
Some(Interpolate::lerp(cp0.value, cp1.value, cos_nt))
}
@@ -275,23 +258,25 @@ impl<T, V> Spline<T, V> {
/// # Error
///
/// This function returns `None` if you have no key.
pub fn clamped_sample(&self, t: f32) -> Option<T> where T: Interpolate {
pub fn clamped_sample(&self, t: T) -> Option<V> where T: Float + FloatConst, V: Interpolate<T> {
if self.0.is_empty() {
return None;
}
let first = self.0.first().unwrap();
let last = self.0.last().unwrap();
self.sample(t).or_else(move || {
let first = self.0.first().unwrap();
if t <= first.t {
Some(first.value)
} else {
let last = self.0.last().unwrap();
let sampled = if t <= first.t {
first.value
} else if t >= last.t {
last.value
} else {
self.sample(t).unwrap()
};
Some(sampled)
if t >= last.t {
Some(last.value)
} else {
None
}
}
})
}
}
@@ -334,7 +319,7 @@ impl<'a, T, V> IntoIterator for &'a Spline<T, V> {
///
/// `T` is the variable used to sample with. Typical implementations use `f32` or `f64`, but you’re
/// free to use the ones you like.
pub trait Interpolate<T>: Copy where T: Copy + Float {
pub trait Interpolate<T>: Sized + Copy {
/// Linear interpolation.
fn lerp(a: Self, b: Self, t: T) -> Self;
@@ -346,145 +331,94 @@ pub trait Interpolate<T>: Copy where T: Copy + Float {
}
}
impl Interpolate<f32> for f32 {
fn lerp(a: Self, b: Self, t: f32) -> Self {
a * (1. - t) + b * t
}
macro_rules! impl_interpolate_simple {
($t:ty) => {
impl Interpolate<$t> for $t {
fn lerp(a: Self, b: Self, t: $t) -> Self {
a * (1. - t) + b * t
}
fn cubic_hermite(x: (Self, f32), a: (Self, f32), b: (Self, f32), y: (Self, f32), t: f32) -> Self {
cubic_hermite(x, a, b, y, t)
fn cubic_hermite(x: (Self, $t), a: (Self, $t), b: (Self, $t), y: (Self, $t), t: $t) -> Self {
cubic_hermite_def(x, a, b, y, t)
}
}
}
}
impl Interpolate<f32> for f64 {
fn lerp(a: Self, b: Self, t: f32) -> Self {
a * (1. - t as f64) + b * t as f64
}
impl_interpolate_simple!(f32);
impl_interpolate_simple!(f64);
fn cubic_hermite(
(x, tx): (Self, f32),
(a, ta): (Self, f32),
(b, tb): (Self, f32),
(y, ty): (Self, f32),
t: f32
) -> Self {
cubic_hermite((x, tx as f64), (a, ta as f64), (b, tb as f64), (y, ty as f64), t as f64)
macro_rules! impl_interpolate_via {
($t:ty, $v:ty) => {
impl Interpolate<$t> for $v {
fn lerp(a: Self, b: Self, t: $t) -> Self {
a * (1. - t as $v) + b * t as $v
}
fn cubic_hermite((x, xt): (Self, $t), (a, at): (Self, $t), (b, bt): (Self, $t), (y, yt): (Self, $t), t: $t) -> Self {
cubic_hermite_def((x, xt as $v), (a, at as $v), (b, bt as $v), (y, yt as $v), t as $v)
}
}
}
}
#[cfg(feature = "impl-cgmath")]
impl<T> Interpolate<T> for Vector2<T> where T: BaseFloat {
fn lerp(a: Self, b: Self, t: T) -> Self {
a.lerp(b, t)
}
impl_interpolate_via!(f32, f64);
impl_interpolate_via!(f64, f32);
fn cubic_hermite(x: (Self, T), a: (Self, T), b: (Self, T), y: (Self, T), t: T) -> Self {
cubic_hermite(x, a, b, y, t)
macro_rules! impl_interpolate_na_vector {
($($t:tt)*) => {
#[cfg(feature = "impl-nalgebra")]
impl<T, V> Interpolate<T> for $($t)*<V> where T: Float, V: na::Scalar + Interpolate<T> {
fn lerp(a: Self, b: Self, t: T) -> Self {
na::Vector::zip_map(&a, &b, |c1, c2| Interpolate::lerp(c1, c2, t))
}
}
}
}
#[cfg(feature = "impl-cgmath")]
impl<T> Interpolate<T> for Vector3<T> where T: BaseFloat {
fn lerp(a: Self, b: Self, t: T) -> Self {
a.lerp(b, t)
}
fn cubic_hermite(x: (Self, T), a: (Self, T), b: (Self, T), y: (Self, T), t: T) -> Self {
cubic_hermite(x, a, b, y, t)
}
}
#[cfg(feature = "impl-cgmath")]
impl<T> Interpolate<T> for Vector4<T> where T: BaseFloat {
fn lerp(a: Self, b: Self, t: T) -> Self {
a.lerp(b, t)
}
fn cubic_hermite(x: (Self, T), a: (Self, T), b: (Self, T), y: (Self, T), t: T) -> Self {
cubic_hermite(x, a, b, y, t)
}
}
#[cfg(feature = "impl-cgmath")]
impl<T> Interpolate<T> for Quaternion<T> where T: BaseFloat {
fn lerp(a: Self, b: Self, t: T) -> Self {
a.nlerp(b, t)
}
}
impl_interpolate_na_vector!(na::Vector1);
impl_interpolate_na_vector!(na::Vector2);
impl_interpolate_na_vector!(na::Vector3);
impl_interpolate_na_vector!(na::Vector4);
impl_interpolate_na_vector!(na::Vector5);
impl_interpolate_na_vector!(na::Vector6);
#[cfg(feature = "impl-nalgebra")]
impl<N, D> Interpolate for na::Point<N, D>
where D: DimName,
DefaultAllocator: Allocator<N, D>,
<DefaultAllocator as Allocator<N, D>>::Buffer: Copy,
N: Scalar + Interpolate {
fn lerp(a: Self, b: Self, t: f32) -> Self {
impl<T, N, D> Interpolate<T> for na::Point<N, D>
where D: na::DimName,
na::DefaultAllocator: na::allocator::Allocator<N, D>,
<na::DefaultAllocator as na::allocator::Allocator<N, D>>::Buffer: Copy,
N: na::Scalar + Interpolate<T>,
T: Float {
fn lerp(a: Self, b: Self, t: T) -> Self {
// The 'coords' of a point is just a vector, so we can interpolate component-wise
// over these vectors.
let coords = na::Vector::zip_map(&a.coords, &b.coords, |c1, c2| Interpolate::lerp(c1, c2, t));
na::Point::from_coordinates(coords)
}
}
#[cfg(feature = "impl-nalgebra")]
impl Interpolate for na::Vector1<f32> {
fn lerp(a: Self, b: Self, t: f32) -> Self {
na::Vector::zip_map(&a, &b, |c1, c2| Interpolate::lerp(c1, c2, t))
}
}
#[cfg(feature = "impl-nalgebra")]
impl Interpolate for na::Vector2<f32> {
fn lerp(a: Self, b: Self, t: f32) -> Self {
na::Vector::zip_map(&a, &b, |c1, c2| Interpolate::lerp(c1, c2, t))
}
}
#[cfg(feature = "impl-nalgebra")]
impl Interpolate for na::Vector3<f32> {
fn lerp(a: Self, b: Self, t: f32) -> Self {
na::Vector::zip_map(&a, &b, |c1, c2| Interpolate::lerp(c1, c2, t))
}
}
#[cfg(feature = "impl-nalgebra")]
impl Interpolate for na::Vector4<f32> {
fn lerp(a: Self, b: Self, t: f32) -> Self {
na::Vector::zip_map(&a, &b, |c1, c2| Interpolate::lerp(c1, c2, t))
}
}
#[cfg(feature = "impl-nalgebra")]
impl Interpolate for na::Vector5<f32> {
fn lerp(a: Self, b: Self, t: f32) -> Self {
na::Vector::zip_map(&a, &b, |c1, c2| Interpolate::lerp(c1, c2, t))
}
}
#[cfg(feature = "impl-nalgebra")]
impl Interpolate for na::Vector6<f32> {
fn lerp(a: Self, b: Self, t: f32) -> Self {
na::Vector::zip_map(&a, &b, |c1, c2| Interpolate::lerp(c1, c2, t))
na::Point::from(coords)
}
}
// Default implementation of Interpolate::cubic_hermite.
//
// `V` is the value being interpolated. `T` is the sampling value (also sometimes called time).
pub(crate) fn cubic_hermite<V, T>(x: (V, T), a: (V, T), b: (V, T), y: (V, T), t: T) -> V
where V: Copy + Add<Output = V> + Sub<Output = V> + Mul<T, Output = V> + Div<T, Output = V>,
T: Mul<Output = T> + Mul<f32, Output = T> + Add<Output = T> + Add<f32, Output = T> + Sub<Output = T> {
pub(crate) fn cubic_hermite_def<V, T>(x: (V, T), a: (V, T), b: (V, T), y: (V, T), t: T) -> V
where V: Float + Mul<T, Output = V> + Div<T, Output = V>,
T: Float {
// some stupid generic constants, because Rust doesn’t have polymorphic literals…
let two_t = T::one() + T::one(); // lolololol
let three_t = two_t + T::one(); // megalol
// sampler stuff
let t2 = t* t;
let t2 = t * t;
let t3 = t2 * t;
let two_t3 = t3 * 2.;
let three_t2 = t2 * 3.;
let two_t3 = t3 * two_t;
let three_t2 = t2 * three_t;
// tangents
let m0 = (b.0 - x.0) / (b.1 - x.1);
let m1 = (y.0 - a.0) / (y.1 - a.1);
let m1 = (y.0 - a.0) / (y.1 - a.1);
a.0 * (two_t3 - three_t2 + 1.) + m0 * (t3 - t2 * 2. + t) + b.0 * (three_t2 - two_t3) + m1 * (t3 - t2)
a.0 * (two_t3 - three_t2 + T::one()) + m0 * (t3 - t2 * two_t + t) + b.0 * (three_t2 - two_t3) + m1 * (t3 - t2)
}
// Normalize a time ([0;1]) given two control points.
@@ -493,7 +427,7 @@ pub(crate) fn normalize_time<T, V>(
t: T,
cp: &Key<T, V>,
cp1: &Key<T, V>
) -> T where T: PartialEq + Sub<Output = T> + Div<Output = T> {
) -> T where T: Float {
assert!(cp1.t != cp.t, "overlapping keys");
(t - cp.t) / (cp1.t - cp.t)
}

11
tests/mod.rs
View File

@@ -1,10 +1,5 @@
extern crate splines;
#[cfg(feature = "impl-nalgebra")] extern crate nalgebra;
#[cfg(feature = "impl-nalgebra")] use nalgebra as na;
#[cfg(feature = "impl-nalgebra")] use splines::Interpolate;
use splines::{Interpolation, Key, Spline};
use splines::{Interpolate, Interpolation, Key, Spline};
use nalgebra as na;
#[test]
fn step_interpolation_0() {
@@ -125,7 +120,7 @@ fn several_interpolations_several_keys() {
assert_eq!(spline.sample(1.5), Some(2.5));
assert_eq!(spline.sample(2.), Some(0.));
assert_eq!(spline.sample(2.05), Some(0.));
assert_eq!(spline.sample(2.1), Some(0.));
assert_eq!(spline.sample(2.099), Some(0.));
assert_eq!(spline.sample(2.75), Some(1.));
assert_eq!(spline.sample(3.), Some(1.));
assert_eq!(spline.sample(6.5), Some(1.5));