cgmath/src/mat2.rs
Brendan Zabarauskas e939b5eb95 Long lines
2012-12-16 08:30:44 +10:00

403 lines
No EOL
10 KiB
Rust

use core::cast::transmute;
use core::cmp::Eq;
use core::ptr::to_unsafe_ptr;
use core::vec::raw::buf_as_slice;
use std::cmp::FuzzyEq;
use angle::Angle;
use funs::common::*;
use funs::exponential::*;
use funs::triganomic::{sin, cos};
use num::types::{Float, Number};
use vec::Vec2;
/**
* A 2 x 2 column major matrix
*
* # Type parameters
*
* * `T` - The type of the elements of the matrix. Should be a floating point type.
*
* # Fields
*
* * `x` - the first column vector of the matrix
* * `y` - the second column vector of the matrix
* * `z` - the third column vector of the matrix
*/
pub struct Mat2<T> { x: Vec2<T>, y: Vec2<T> }
pub impl<T:Copy Float> Mat2<T> {
/**
* Construct a 2 x 2 matrix
*
* # Arguments
*
* * `c0r0`, `c0r1` - the first column of the matrix
* * `c1r0`, `c1r1` - the second column of the matrix
*
* ~~~
* c0 c1
* +------+------+
* r0 | c0r0 | c1r0 |
* +------+------+
* r1 | c0r1 | c1r1 |
* +------+------+
* ~~~
*/
#[inline(always)]
static pure fn new(c0r0: T, c0r1: T,
c1r0: T, c1r1: T) -> Mat2<T> {
Mat2::from_cols(Vec2::new(move c0r0, move c0r1),
Vec2::new(move c1r0, move c1r1))
}
/**
* Construct a 2 x 2 matrix from column vectors
*
* # Arguments
*
* * `c0` - the first column vector of the matrix
* * `c1` - the second column vector of the matrix
*
* ~~~
* c0 c1
* +------+------+
* r0 | c0.x | c1.x |
* +------+------+
* r1 | c0.y | c1.y |
* +------+------+
* ~~~
*/
#[inline(always)]
static pure fn from_cols(c0: Vec2<T>,
c1: Vec2<T>) -> Mat2<T> {
Mat2 { x: move c0,
y: move c1 }
}
/**
* Construct a 2 x 2 diagonal matrix with the major diagonal set to `value`
*
* # Arguments
*
* * `value` - the value to set the major diagonal to
*
* ~~~
* c0 c1
* +-----+-----+
* r0 | val | 0 |
* +-----+-----+
* r1 | 0 | val |
* +-----+-----+
* ~~~
*/
#[inline(always)]
static pure fn from_value(value: T) -> Mat2<T> {
let _0 = Number::from(0);
Mat2::new(value, _0,
_0, value)
}
// FIXME: An interim solution to the issues with static functions
#[inline(always)]
static pure fn from_angle<A:Angle<T>>(theta: A) -> Mat2<T> {
let cos_theta = cos(&theta.to_radians());
let sin_theta = sin(&theta.to_radians());
Mat2::new(cos_theta, -sin_theta,
sin_theta, cos_theta)
}
// FIXME: An interim solution to the issues with static functions
#[inline(always)]
static pure fn identity() -> Mat2<T> {
let _0 = Number::from(0);
let _1 = Number::from(1);
Mat2::new(_1, _0,
_0, _1)
}
// FIXME: An interim solution to the issues with static functions
#[inline(always)]
static pure fn zero() -> Mat2<T> {
let _0 = Number::from(0);
Mat2::new(_0, _0,
_0, _0)
}
}
pub impl<T:Copy Float> Mat2<T>: Matrix<T, Vec2<T>> {
#[inline(always)]
pure fn col(&self, i: uint) -> Vec2<T> { self[i] }
#[inline(always)]
pure fn row(&self, i: uint) -> Vec2<T> {
Vec2::new(self[0][i],
self[1][i])
}
/**
* Returns the multiplicative identity matrix
* ~~~
* c0 c1
* +----+----+
* r0 | 1 | 0 |
* +----+----+
* r1 | 0 | 1 |
* +----+----+
* ~~~
*/
#[inline(always)]
static pure fn identity() -> Mat2<T> {
let _0 = Number::from(0);
let _1 = Number::from(1);
Mat2::new(_1, _0,
_0, _1)
}
/**
* Returns the additive identity matrix
* ~~~
* c0 c1
* +----+----+
* r0 | 0 | 0 |
* +----+----+
* r1 | 0 | 0 |
* +----+----+
* ~~~
*/
#[inline(always)]
static pure fn zero() -> Mat2<T> {
let _0 = Number::from(0);
Mat2::new(_0, _0,
_0, _0)
}
#[inline(always)]
pure fn mul_t(&self, value: T) -> Mat2<T> {
Mat2::from_cols(self[0].mul_t(value),
self[1].mul_t(value))
}
#[inline(always)]
pure fn mul_v(&self, vec: &Vec2<T>) -> Vec2<T> {
Vec2::new(self.row(0).dot(vec),
self.row(1).dot(vec))
}
#[inline(always)]
pure fn add_m(&self, other: &Mat2<T>) -> Mat2<T> {
Mat2::from_cols(self[0].add_v(&other[0]),
self[1].add_v(&other[1]))
}
#[inline(always)]
pure fn sub_m(&self, other: &Mat2<T>) -> Mat2<T> {
Mat2::from_cols(self[0].sub_v(&other[0]),
self[1].sub_v(&other[1]))
}
#[inline(always)]
pure fn mul_m(&self, other: &Mat2<T>) -> Mat2<T> {
Mat2::new(self.row(0).dot(&other.col(0)), self.row(1).dot(&other.col(0)),
self.row(0).dot(&other.col(1)), self.row(1).dot(&other.col(1)))
}
pure fn dot(&self, other: &Mat2<T>) -> T {
other.transpose().mul_m(self).trace()
}
pure fn determinant(&self) -> T {
self[0][0] * self[1][1] - self[1][0] * self[0][1]
}
pure fn trace(&self) -> T {
self[0][0] + self[1][1]
}
#[inline(always)]
pure fn inverse(&self) -> Option<Mat2<T>> {
let d = self.determinant();
if d.fuzzy_eq(&Number::from(0)) {
None
} else {
Some(Mat2::new( self[1][1]/d, -self[0][1]/d,
-self[1][0]/d, self[0][0]/d))
}
}
#[inline(always)]
pure fn transpose(&self) -> Mat2<T> {
Mat2::new(self[0][0], self[1][0],
self[0][1], self[1][1])
}
#[inline(always)]
pure fn is_identity(&self) -> bool {
// self.fuzzy_eq(&Matrix::identity()) // FIXME: there's something wrong with static functions here!
self.fuzzy_eq(&Mat2::identity())
}
#[inline(always)]
pure fn is_diagonal(&self) -> bool {
let _0 = Number::from(0);
self[0][1].fuzzy_eq(&_0) &&
self[1][0].fuzzy_eq(&_0)
}
#[inline(always)]
pure fn is_rotated(&self) -> bool {
// !self.fuzzy_eq(&Matrix::identity()) // FIXME: there's something wrong with static functions here!
!self.fuzzy_eq(&Mat2::identity())
}
#[inline(always)]
pure fn is_symmetric(&self) -> bool {
self[0][1].fuzzy_eq(&self[1][0]) &&
self[1][0].fuzzy_eq(&self[0][1])
}
#[inline(always)]
pure fn is_invertible(&self) -> bool {
!self.determinant().fuzzy_eq(&Number::from(0))
}
#[inline(always)]
pure fn to_ptr(&self) -> *T {
unsafe {
transmute::<*Mat2<T>, *T>(
to_unsafe_ptr(self)
)
}
}
}
pub impl<T:Copy Float Sign> Mat2<T>: MutableMatrix<T, Vec2<T>> {
#[inline(always)]
fn col_mut(&mut self, i: uint) -> &self/mut Vec2<T> {
match i {
0 => &mut self.x,
1 => &mut self.y,
_ => fail(fmt!("index out of bounds: expected an index from 0 to 1, but found %u", i))
}
}
#[inline(always)]
fn swap_cols(&mut self, a: uint, b: uint) {
util::swap(self.col_mut(a),
self.col_mut(b));
}
#[inline(always)]
fn swap_rows(&mut self, a: uint, b: uint) {
self.x.swap(a, b);
self.y.swap(a, b);
}
#[inline(always)]
fn set(&mut self, other: &Mat2<T>) {
(*self) = (*other);
}
#[inline(always)]
fn to_identity(&mut self) {
(*self) = Mat2::identity();
}
#[inline(always)]
fn to_zero(&mut self) {
(*self) = Mat2::zero();
}
#[inline(always)]
fn mul_self_t(&mut self, value: T) {
self.col_mut(0).mul_self_t(&value);
self.col_mut(1).mul_self_t(&value);
}
#[inline(always)]
fn add_self_m(&mut self, other: &Mat2<T>) {
self.col_mut(0).add_self_v(&other[0]);
self.col_mut(1).add_self_v(&other[1]);
}
#[inline(always)]
fn sub_self_m(&mut self, other: &Mat2<T>) {
self.col_mut(0).sub_self_v(&other[0]);
self.col_mut(1).sub_self_v(&other[1]);
}
#[inline(always)]
fn invert_self(&mut self) {
match self.inverse() {
Some(m) => (*self) = m,
None => fail(~"Couldn't invert the matrix!")
}
}
#[inline(always)]
fn transpose_self(&mut self) {
util::swap(self.col_mut(0).index_mut(1), self.col_mut(1).index_mut(0));
util::swap(self.col_mut(1).index_mut(0), self.col_mut(0).index_mut(1));
}
}
pub impl<T:Copy Float> Mat2<T>: Matrix2<T, Vec2<T>> {
#[inline(always)]
pure fn to_mat3(&self) -> Mat3<T> {
let _0 = Number::from(0);
let _1 = Number::from(1);
Mat3::new(self[0][0], self[0][1], _0,
self[1][0], self[1][1], _0,
_0, _0, _1)
}
#[inline(always)]
pure fn to_mat4(&self) -> Mat4<T> {
let _0 = Number::from(0);
let _1 = Number::from(1);
Mat4::new(self[0][0], self[0][1], _0, _0,
self[1][0], self[1][1], _0, _0,
_0, _0, _1, _0,
_0, _0, _0, _1)
}
}
pub impl<T:Copy> Mat2<T>: Index<uint, Vec2<T>> {
#[inline(always)]
pure fn index(&self, i: uint) -> Vec2<T> {
unsafe { do buf_as_slice(
transmute::<*Mat2<T>, *Vec2<T>>(
to_unsafe_ptr(self)), 2) |slice| { slice[i] }
}
}
}
pub impl<T:Copy Float> Mat2<T>: Neg<Mat2<T>> {
#[inline(always)]
pure fn neg(&self) -> Mat2<T> {
Mat2::from_cols(-self[0], -self[1])
}
}
pub impl<T:Copy Float> Mat2<T>: Eq {
#[inline(always)]
pure fn eq(&self, other: &Mat2<T>) -> bool {
self[0] == other[0] &&
self[1] == other[1]
}
#[inline(always)]
pure fn ne(&self, other: &Mat2<T>) -> bool {
!(self == other)
}
}
pub impl<T:Copy Float> Mat2<T>: FuzzyEq {
#[inline(always)]
pure fn fuzzy_eq(other: &Mat2<T>) -> bool {
self[0].fuzzy_eq(&other[0]) &&
self[1].fuzzy_eq(&other[1])
}
}