cgmath/src/vec2.rs
2013-06-16 02:08:16 +02:00

553 lines
14 KiB
Rust

// Copyright 2013 The Lmath Developers. For a full listing of the authors,
// refer to the AUTHORS file at the top-level directory of this distribution.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
use std::cast::transmute;
use std::cmp::ApproxEq;
use std::num::{Zero, One};
use super::Dimensional;
use super::Vec3;
#[deriving(Eq)]
pub struct Vec2<T> { x: T, y: T }
impl<T> Vec2<T> {
#[inline]
pub fn new(x: T, y: T ) -> Vec2<T> {
Vec2 { x: x, y: y }
}
}
impl<T> Dimensional<T,[T,..2]> for Vec2<T> {
#[inline]
pub fn index<'a>(&'a self, i: uint) -> &'a T {
&'a self.as_slice()[i]
}
#[inline]
pub fn index_mut<'a>(&'a mut self, i: uint) -> &'a mut T {
&'a mut self.as_mut_slice()[i]
}
#[inline]
pub fn as_slice<'a>(&'a self) -> &'a [T,..2] {
unsafe { transmute(self) }
}
#[inline]
pub fn as_mut_slice<'a>(&'a mut self) -> &'a mut [T,..2] {
unsafe { transmute(self) }
}
#[inline(always)]
pub fn map(&self, f: &fn(&T) -> T) -> Vec2<T> {
Vec2::new(f(self.index(0)),
f(self.index(1)))
}
#[inline(always)]
pub fn map_mut(&mut self, f: &fn(&mut T)) {
f(self.index_mut(0));
f(self.index_mut(1));
}
}
impl<T:Copy> Vec2<T> {
#[inline]
pub fn from_value(value: T) -> Vec2<T> {
Vec2::new(value, value)
}
#[inline]
pub fn swap(&mut self, a: uint, b: uint) {
let tmp = *self.index(a);
*self.index_mut(a) = *self.index(b);
*self.index_mut(b) = tmp;
}
}
impl<T:Copy + Num> Vec2<T> {
#[inline]
pub fn identity() -> Vec2<T> {
Vec2::new(One::one::<T>(), One::one::<T>())
}
#[inline]
pub fn zero() -> Vec2<T> {
Vec2::new(Zero::zero::<T>(), Zero::zero::<T>())
}
#[inline]
pub fn unit_x() -> Vec2<T> {
Vec2::new(One::one::<T>(), Zero::zero::<T>())
}
#[inline]
pub fn unit_y() -> Vec2<T> {
Vec2::new(Zero::zero::<T>(), One::one::<T>())
}
#[inline]
pub fn is_zero(&self) -> bool {
*self.index(0) == Zero::zero() &&
*self.index(1) == Zero::zero()
}
#[inline]
pub fn add_t(&self, value: T) -> Vec2<T> {
self.map(|&x| x + value)
}
#[inline]
pub fn sub_t(&self, value: T) -> Vec2<T> {
self.map(|&x| x - value)
}
#[inline]
pub fn mul_t(&self, value: T) -> Vec2<T> {
self.map(|&x| x * value)
}
#[inline]
pub fn div_t(&self, value: T) -> Vec2<T> {
self.map(|&x| x / value)
}
#[inline]
pub fn rem_t(&self, value: T) -> Vec2<T> {
self.map(|&x| x % value)
}
#[inline]
pub fn add_v(&self, other: &Vec2<T>) -> Vec2<T> {
Vec2::new(*self.index(0) + *other.index(0),
*self.index(1) + *other.index(1))
}
#[inline]
pub fn sub_v(&self, other: &Vec2<T>) -> Vec2<T> {
Vec2::new(*self.index(0) - *other.index(0),
*self.index(1) - *other.index(1))
}
#[inline]
pub fn mul_v(&self, other: &Vec2<T>) -> Vec2<T> {
Vec2::new(*self.index(0) * *other.index(0),
*self.index(1) * *other.index(1))
}
#[inline]
pub fn div_v(&self, other: &Vec2<T>) -> Vec2<T> {
Vec2::new(*self.index(0) / *other.index(0),
*self.index(1) / *other.index(1))
}
#[inline]
pub fn rem_v(&self, other: &Vec2<T>) -> Vec2<T> {
Vec2::new(*self.index(0) % *other.index(0),
*self.index(1) % *other.index(1))
}
#[inline]
pub fn neg_self(&mut self) {
self.map_mut(|x| *x = -*x)
}
#[inline]
pub fn add_self_t(&mut self, value: T) {
self.map_mut(|x| *x += value)
}
#[inline]
pub fn sub_self_t(&mut self, value: T) {
self.map_mut(|x| *x -= value)
}
#[inline]
pub fn mul_self_t(&mut self, value: T) {
self.map_mut(|x| *x *= value)
}
#[inline]
pub fn div_self_t(&mut self, value: T) {
self.map_mut(|x| *x /= value)
}
#[inline]
pub fn rem_self_t(&mut self, value: T) {
self.map_mut(|x| *x %= value)
}
#[inline]
pub fn add_self_v(&mut self, other: &Vec2<T>) {
*self.index_mut(0) += *other.index(0);
*self.index_mut(1) += *other.index(1);
}
#[inline]
pub fn sub_self_v(&mut self, other: &Vec2<T>) {
*self.index_mut(0) -= *other.index(0);
*self.index_mut(1) -= *other.index(1);
}
#[inline]
pub fn mul_self_v(&mut self, other: &Vec2<T>) {
*self.index_mut(0) *= *other.index(0);
*self.index_mut(1) *= *other.index(1);
}
#[inline]
pub fn div_self_v(&mut self, other: &Vec2<T>) {
*self.index_mut(0) /= *other.index(0);
*self.index_mut(1) /= *other.index(1);
}
#[inline]
pub fn rem_self_v(&mut self, other: &Vec2<T>) {
*self.index_mut(0) /= *other.index(0);
*self.index_mut(1) /= *other.index(1);
}
#[inline]
pub fn dot(&self, other: &Vec2<T>) -> T {
*self.index(0) * *other.index(0) +
*self.index(1) * *other.index(1)
}
#[inline]
pub fn perp_dot(&self, other: &Vec2<T>) -> T {
(*self.index(0) * *other.index(1)) -
(*self.index(1) * *other.index(0))
}
#[inline]
pub fn to_homogeneous(&self) -> Vec3<T> {
Vec3::new(self.x, self.y, Zero::zero())
}
}
impl<T:Copy + Num> Neg<Vec2<T>> for Vec2<T> {
#[inline]
pub fn neg(&self) -> Vec2<T> {
self.map(|&x| -x)
}
}
impl<T:Copy + Real> Vec2<T> {
#[inline]
pub fn length2(&self) -> T {
self.dot(self)
}
#[inline]
pub fn length(&self) -> T {
self.length2().sqrt()
}
#[inline]
pub fn distance2(&self, other: &Vec2<T>) -> T {
other.sub_v(self).length2()
}
#[inline]
pub fn distance(&self, other: &Vec2<T>) -> T {
other.distance2(self).sqrt()
}
#[inline]
pub fn angle(&self, other: &Vec2<T>) -> T {
self.perp_dot(other).atan2(&self.dot(other))
}
#[inline]
pub fn normalize(&self) -> Vec2<T> {
self.mul_t(One::one::<T>()/self.length())
}
#[inline]
pub fn normalize_to(&self, length: T) -> Vec2<T> {
self.mul_t(length / self.length())
}
#[inline]
pub fn lerp(&self, other: &Vec2<T>, amount: T) -> Vec2<T> {
self.add_v(&other.sub_v(self).mul_t(amount))
}
#[inline]
pub fn normalize_self(&mut self) {
let n = One::one::<T>() / self.length();
self.mul_self_t(n);
}
#[inline]
pub fn normalize_self_to(&mut self, length: T) {
let n = length / self.length();
self.mul_self_t(n);
}
pub fn lerp_self(&mut self, other: &Vec2<T>, amount: T) {
let v = other.sub_v(self).mul_t(amount);
self.add_self_v(&v);
}
}
impl<T:Copy + Eq + ApproxEq<T>> ApproxEq<T> for Vec2<T> {
#[inline]
pub fn approx_epsilon() -> T {
ApproxEq::approx_epsilon::<T,T>()
}
#[inline]
pub fn approx_eq(&self, other: &Vec2<T>) -> bool {
self.approx_eq_eps(other, &ApproxEq::approx_epsilon::<T,T>())
}
#[inline]
pub fn approx_eq_eps(&self, other: &Vec2<T>, epsilon: &T) -> bool {
self.index(0).approx_eq_eps(other.index(0), epsilon) &&
self.index(1).approx_eq_eps(other.index(1), epsilon)
}
}
impl<T:Copy + Ord> Vec2<T> {
#[inline]
pub fn lt_t(&self, value: T) -> Vec2<bool> {
Vec2::new(*self.index(0) < value,
*self.index(1) < value)
}
#[inline]
pub fn le_t(&self, value: T) -> Vec2<bool> {
Vec2::new(*self.index(0) <= value,
*self.index(1) <= value)
}
#[inline]
pub fn ge_t(&self, value: T) -> Vec2<bool> {
Vec2::new(*self.index(0) >= value,
*self.index(1) >= value)
}
#[inline]
pub fn gt_t(&self, value: T) -> Vec2<bool> {
Vec2::new(*self.index(0) > value,
*self.index(1) > value)
}
#[inline]
pub fn lt_v(&self, other: &Vec2<T>) -> Vec2<bool> {
Vec2::new(*self.index(0) < *other.index(0),
*self.index(1) < *other.index(1))
}
#[inline]
pub fn le_v(&self, other: &Vec2<T>) -> Vec2<bool> {
Vec2::new(*self.index(0) <= *other.index(0),
*self.index(1) <= *other.index(1))
}
#[inline]
pub fn ge_v(&self, other: &Vec2<T>) -> Vec2<bool> {
Vec2::new(*self.index(0) >= *other.index(0),
*self.index(1) >= *other.index(1))
}
#[inline]
pub fn gt_v(&self, other: &Vec2<T>) -> Vec2<bool> {
Vec2::new(*self.index(0) > *other.index(0),
*self.index(1) > *other.index(1))
}
}
impl<T:Copy + Eq> Vec2<T> {
#[inline]
pub fn eq_t(&self, value: T) -> Vec2<bool> {
Vec2::new(*self.index(0) == value,
*self.index(1) == value)
}
#[inline]
pub fn ne_t(&self, value: T) -> Vec2<bool> {
Vec2::new(*self.index(0) != value,
*self.index(1) != value)
}
#[inline]
pub fn eq_v(&self, other: &Vec2<T>) -> Vec2<bool> {
Vec2::new(*self.index(0) == *other.index(0),
*self.index(1) == *other.index(1))
}
#[inline]
pub fn ne_v(&self, other: &Vec2<T>) -> Vec2<bool> {
Vec2::new(*self.index(0) != *other.index(0),
*self.index(1) != *other.index(1))
}
}
impl Vec2<bool> {
#[inline]
pub fn any(&self) -> bool {
*self.index(0) || *self.index(1)
}
#[inline]
pub fn all(&self) -> bool {
*self.index(0) && *self.index(1)
}
#[inline]
pub fn not(&self) -> Vec2<bool> {
self.map(|&x| !x)
}
}
#[cfg(test)]
mod tests {
use vec::*;
#[test]
fn test_vec2() {
let a = Vec2 { x: 1.0, y: 2.0 };
let b = Vec2 { x: 3.0, y: 4.0 };
let f1 = 1.5;
let f2 = 0.5;
let mut mut_a = a;
assert_eq!(Vec2::new::<float>(1.0, 2.0), a);
assert_eq!(Vec2::from_value(1.0), Vec2::new::<float>(1.0, 1.0));
assert_eq!(Vec2::zero(), Vec2::new::<float>(0.0, 0.0));
assert_eq!(Vec2::unit_x(), Vec2::new::<float>(1.0, 0.0));
assert_eq!(Vec2::unit_y(), Vec2::new::<float>(0.0, 1.0));
assert_eq!(Vec2::identity(), Vec2::new::<float>(1.0, 1.0));
*mut_a.index_mut(0) = 42.0;
*mut_a.index_mut(1) = 43.0;
assert_eq!(mut_a, Vec2::new::<float>(42.0, 43.0));
mut_a = a;
mut_a.swap(0, 1);
assert_eq!(*mut_a.index(0), *a.index(1));
assert_eq!(*mut_a.index(1), *a.index(0));
mut_a = a;
assert_eq!(a.x, 1.0);
assert_eq!(a.y, 2.0);
assert_eq!(*a.index(0), 1.0);
assert_eq!(*a.index(1), 2.0);
assert_eq!(-a, Vec2::new::<float>(-1.0, -2.0));
assert_eq!(a.neg(), Vec2::new::<float>(-1.0, -2.0));
assert!(Vec2::new::<float>(0.0, 0.0).is_zero());
assert!(!Vec2::new::<float>(1.0, 1.0).is_zero());
assert_eq!(a.mul_t(f1), Vec2::new::<float>( 1.5, 3.0));
assert_eq!(a.div_t(f2), Vec2::new::<float>( 2.0, 4.0));
assert_eq!(a.add_v(&b), Vec2::new::<float>( 4.0, 6.0));
assert_eq!(a.sub_v(&b), Vec2::new::<float>( -2.0, -2.0));
assert_eq!(a.mul_v(&b), Vec2::new::<float>( 3.0, 8.0));
assert_eq!(a.div_v(&b), Vec2::new::<float>(1.0/3.0, 2.0/4.0));
mut_a.neg_self();
assert_eq!(mut_a, -a);
mut_a = a;
mut_a.mul_self_t(f1);
assert_eq!(mut_a, a.mul_t(f1));
mut_a = a;
mut_a.div_self_t(f2);
assert_eq!(mut_a, a.div_t(f2));
mut_a = a;
mut_a.add_self_v(&b);
assert_eq!(mut_a, a.add_v(&b));
mut_a = a;
mut_a.sub_self_v(&b);
assert_eq!(mut_a, a.sub_v(&b));
mut_a = a;
mut_a.mul_self_v(&b);
assert_eq!(mut_a, a.mul_v(&b));
mut_a = a;
mut_a.div_self_v(&b);
assert_eq!(mut_a, a.div_v(&b));
}
#[test]
fn test_vec2_approx_eq() {
assert!(!Vec2::new::<float>(0.000001, 0.000001).approx_eq(&Vec2::new::<float>(0.0, 0.0)));
assert!(Vec2::new::<float>(0.0000001, 0.0000001).approx_eq(&Vec2::new::<float>(0.0, 0.0)));
}
#[test]
fn test_vec2_euclidean() {
let a = Vec2::new::<float>(5.0, 12.0); // (5, 12, 13) Pythagorean triple
let b0 = Vec2::new::<float>(3.0, 4.0); // (3, 4, 5) Pythagorean triple
let b = a.add_v(&b0);
assert_eq!(a.length(), 13.0);
assert_eq!(a.length2(), 13.0 * 13.0);
assert_eq!(b0.length(), 5.0);
assert_eq!(b0.length2(), 5.0 * 5.0);
assert_eq!(a.distance(&b), 5.0);
assert_eq!(a.distance2(&b), 5.0 * 5.0);
assert!(Vec2::new::<float>(1.0, 0.0).angle(&Vec2::new::<float>(0.0, 1.0)).approx_eq(&Real::frac_pi_2()));
assert!(Vec2::new::<float>(10.0, 0.0).angle(&Vec2::new::<float>(0.0, 5.0)).approx_eq(&Real::frac_pi_2()));
assert!(Vec2::new::<float>(-1.0, 0.0).angle(&Vec2::new::<float>(0.0, 1.0)).approx_eq(&-Real::frac_pi_2::<float>()));
assert!(Vec2::new::<float>(3.0, 4.0).normalize().approx_eq(&Vec2::new::<float>(3.0/5.0, 4.0/5.0)));
// TODO: test normalize_to, normalize_self, and normalize_self_to
let c = Vec2::new::<float>(-2.0, -1.0);
let d = Vec2::new::<float>( 1.0, 0.0);
assert_eq!(c.lerp(&d, 0.75), Vec2::new::<float>(0.250, -0.250));
let mut mut_c = c;
mut_c.lerp_self(&d, 0.75);
assert_eq!(mut_c, c.lerp(&d, 0.75));
}
#[test]
fn test_vec2_boolean() {
let tf = Vec2::new(true, false);
let ff = Vec2::new(false, false);
let tt = Vec2::new(true, true);
assert_eq!(tf.any(), true);
assert_eq!(tf.all(), false);
assert_eq!(tf.not(), Vec2::new(false, true));
assert_eq!(ff.any(), false);
assert_eq!(ff.all(), false);
assert_eq!(ff.not(), Vec2::new(true, true));
assert_eq!(tt.any(), true);
assert_eq!(tt.all(), true);
assert_eq!(tt.not(), Vec2::new(false, false));
}
}