nalgebra/src/vec_macros.rs

#[macro_escape];

macro_rules! new_impl(
  ($t: ident, $comp0: ident $(,$compN: ident)*) => (
    impl<N> $t<N>
    {
      /// Creates a new vector.
      #[inline]
      pub fn new($comp0: N $( , $compN: N )*) -> $t<N>
      {
        $t {
          $comp0: $comp0
          $(, $compN: $compN )*
        }
      }
    }
  )
)
macro_rules! vec_cast_impl(
  ($t: ident, $comp0: ident $(,$compN: ident)*) => (
    impl<Nin: NumCast + Clone, Nout: NumCast> VecCast<$t<Nout>> for $t<Nin>
    {
      #[inline]
      pub fn from(v: $t<Nin>) -> $t<Nout>
      { $t::new(NumCast::from(v.$comp0.clone()) $(, NumCast::from(v.$compN.clone()))*) }
    }
  )
)

macro_rules! indexable_impl(
  ($t: ident, $dim: expr) => (
    impl<N: Clone> Indexable<uint, N> for $t<N>
    {
      #[inline]
      pub fn at(&self, i: uint) -> N
      { unsafe { cast::transmute::<&$t<N>, &[N, ..$dim]>(self)[i].clone() } }

      #[inline]
      pub fn set(&mut self, i: uint, val: N)
      { unsafe { cast::transmute::<&mut $t<N>, &mut [N, ..$dim]>(self)[i] = val } }

      #[inline]
      pub fn swap(&mut self, i1: uint, i2: uint)
      { unsafe { cast::transmute::<&mut $t<N>, &mut [N, ..$dim]>(self).swap(i1, i2) } }
    }
  )
)

macro_rules! new_repeat_impl(
  ($t: ident, $param: ident, $comp0: ident $(,$compN: ident)*) => (
    impl<N: Clone> $t<N>
    {
      /// Creates a new vector with all its components equal to a given value.
      #[inline]
      pub fn new_repeat($param: N) -> $t<N>
      {
        $t{
          $comp0: $param.clone()
          $(, $compN: $param.clone() )*
        }
      }
    }
  )
)

macro_rules! iterable_impl(
  ($t: ident, $dim: expr) => (
    impl<N> Iterable<N> for $t<N>
    {
      fn iter<'l>(&'l self) -> VecIterator<'l, N>
      { unsafe { cast::transmute::<&'l $t<N>, &'l [N, ..$dim]>(self).iter() } }
    }
  )
)

macro_rules! iterable_mut_impl(
  ($t: ident, $dim: expr) => (
    impl<N> IterableMut<N> for $t<N>
    {
      fn mut_iter<'l>(&'l mut self) -> VecMutIterator<'l, N>
      { unsafe { cast::transmute::<&'l mut $t<N>, &'l mut [N, ..$dim]>(self).mut_iter() } }
    }
  )
)

macro_rules! dim_impl(
  ($t: ident, $dim: expr) => (
    impl<N> Dim for $t<N>
    {
      #[inline]
      fn dim() -> uint
      { $dim }
    }
  )
)

macro_rules! basis_impl(
  ($t: ident, $dim: expr) => (
    impl<N: Clone + DivisionRing + Algebraic + ApproxEq<N>> Basis for $t<N>
    {
      pub fn canonical_basis(f: &fn($t<N>))
      {
        for iterate(0u, $dim) |i|
        {
          let mut basis_element : $t<N> = Zero::zero();
    
          basis_element.set(i, One::one());
    
          f(basis_element);
        }
      }
    
      pub fn orthonormal_subspace_basis(&self, f: &fn($t<N>))
      {
        // compute the basis of the orthogonal subspace using Gram-Schmidt
        // orthogonalization algorithm
        let mut basis: ~[$t<N>] = ~[];
    
        for iterate(0u, $dim) |i|
        {
          let mut basis_element : $t<N> = Zero::zero();
    
          basis_element.set(i, One::one());
    
          if basis.len() == $dim - 1
          { break; }
    
          let mut elt = basis_element.clone();
    
          elt = elt - self.scalar_mul(&basis_element.dot(self));
    
          for basis.iter().advance |v|
          { elt = elt - v.scalar_mul(&elt.dot(v)) };
    
          if !elt.sqnorm().approx_eq(&Zero::zero())
          {
            let new_element = elt.normalized();

            f(new_element.clone());

            basis.push(new_element);
          }
        }
      }
    }
  )
)

macro_rules! add_impl(
  ($t: ident, $comp0: ident $(,$compN: ident)*) => (
    impl<N: Clone + Add<N,N>> Add<$t<N>, $t<N>> for $t<N>
    {
      #[inline]
      fn add(&self, other: &$t<N>) -> $t<N>
      { $t::new(self.$comp0 + other.$comp0 $(, self.$compN + other.$compN)*) }
    }
  )
)

macro_rules! sub_impl(
  ($t: ident, $comp0: ident $(,$compN: ident)*) => (
    impl<N: Clone + Sub<N,N>> Sub<$t<N>, $t<N>> for $t<N>
    {
      #[inline]
      fn sub(&self, other: &$t<N>) -> $t<N>
      { $t::new(self.$comp0 - other.$comp0 $(, self.$compN - other.$compN)*) }
    }
  )
)

macro_rules! neg_impl(
  ($t: ident, $comp0: ident $(,$compN: ident)*) => (
    impl<N: Neg<N>> Neg<$t<N>> for $t<N>
    {
      #[inline]
      fn neg(&self) -> $t<N>
      { $t::new(-self.$comp0 $(, -self.$compN )*) }
    }
  )
)

macro_rules! dot_impl(
  ($t: ident, $comp0: ident $(,$compN: ident)*) => (
    impl<N: Ring> Dot<N> for $t<N>
    {
      #[inline]
      fn dot(&self, other: &$t<N>) -> N
      { self.$comp0 * other.$comp0 $(+ self.$compN * other.$compN )* } 
    }
  )
)

macro_rules! sub_dot_impl(
  ($t: ident, $comp0: ident $(,$compN: ident)*) => (
    impl<N: Ring> SubDot<N> for $t<N>
    {
      #[inline]
      fn sub_dot(&self, a: &$t<N>, b: &$t<N>) -> N
      { (self.$comp0 - a.$comp0) * b.$comp0 $(+ (self.$compN - a.$compN) * b.$compN )* } 
    }
  )
)

macro_rules! scalar_mul_impl(
  ($t: ident, $comp0: ident $(,$compN: ident)*) => (
    impl<N: Mul<N, N>> ScalarMul<N> for $t<N>
    {
      #[inline]
      fn scalar_mul(&self, s: &N) -> $t<N>
      { $t::new(self.$comp0 * *s $(, self.$compN * *s)*) }
    
      #[inline]
      fn scalar_mul_inplace(&mut self, s: &N)
      {
        self.$comp0   = self.$comp0 * *s;
        $(self.$compN = self.$compN * *s;)*
      }
    }
  )
)

macro_rules! scalar_div_impl(
  ($t: ident, $comp0: ident $(,$compN: ident)*) => (
    impl<N: Div<N, N>> ScalarDiv<N> for $t<N>
    {
      #[inline]
      fn scalar_div(&self, s: &N) -> $t<N>
      { $t::new(self.$comp0 / *s $(, self.$compN / *s)*) }
    
      #[inline]
      fn scalar_div_inplace(&mut self, s: &N)
      {
        self.$comp0   = self.$comp0 / *s;
        $(self.$compN = self.$compN / *s;)*
      }
    }
  )
)

macro_rules! scalar_add_impl(
  ($t: ident, $comp0: ident $(,$compN: ident)*) => (
    impl<N: Add<N, N>> ScalarAdd<N> for $t<N>
    {
      #[inline]
      fn scalar_add(&self, s: &N) -> $t<N>
      { $t::new(self.$comp0 + *s $(, self.$compN + *s)*) }
    
      #[inline]
      fn scalar_add_inplace(&mut self, s: &N)
      {
        self.$comp0   = self.$comp0 + *s;
        $(self.$compN = self.$compN + *s;)*
      }
    }
  )
)

macro_rules! scalar_sub_impl(
  ($t: ident, $comp0: ident $(,$compN: ident)*) => (
    impl<N: Sub<N, N>> ScalarSub<N> for $t<N>
    {
      #[inline]
      fn scalar_sub(&self, s: &N) -> $t<N>
      { $t::new(self.$comp0 - *s $(, self.$compN - *s)*) }
    
      #[inline]
      fn scalar_sub_inplace(&mut self, s: &N)
      {
        self.$comp0   = self.$comp0 - *s;
        $(self.$compN = self.$compN - *s;)*
      }
    }
  )
)

macro_rules! translation_impl(
  ($t: ident) => (
    impl<N: Clone + Add<N, N> + Neg<N>> Translation<$t<N>> for $t<N>
    {
      #[inline]
      fn translation(&self) -> $t<N>
      { self.clone() }

      #[inline]
      fn inv_translation(&self) -> $t<N>
      { -self }
    
      #[inline]
      fn translate_by(&mut self, t: &$t<N>)
      { *self = *self + *t; }
    }
  )
)

macro_rules! translatable_impl(
  ($t: ident) => (
    impl<N: Add<N, N> + Neg<N> + Clone> Translatable<$t<N>, $t<N>> for $t<N>
    {
      #[inline]
      fn translated(&self, t: &$t<N>) -> $t<N>
      { self + *t }
    }
  )
)

macro_rules! norm_impl(
  ($t: ident) => (
    impl<N: Clone + DivisionRing + Algebraic> Norm<N> for $t<N>
    {
      #[inline]
      fn sqnorm(&self) -> N
      { self.dot(self) }
    
      #[inline]
      fn norm(&self) -> N
      { self.sqnorm().sqrt() }
    
      #[inline]
      fn normalized(&self) -> $t<N>
      {
        let mut res : $t<N> = self.clone();
    
        res.normalize();
    
        res
      }
    
      #[inline]
      fn normalize(&mut self) -> N
      {
        let l = self.norm();
    
        self.scalar_div_inplace(&l);
    
        l
      }
    }
  )
)

macro_rules! approx_eq_impl(
  ($t: ident, $comp0: ident $(,$compN: ident)*) => (
    impl<N: ApproxEq<N>> ApproxEq<N> for $t<N>
    {
      #[inline]
      fn approx_epsilon() -> N
      { ApproxEq::approx_epsilon::<N, N>() }
    
      #[inline]
      fn approx_eq(&self, other: &$t<N>) -> bool
      { self.$comp0.approx_eq(&other.$comp0) $(&& self.$compN.approx_eq(&other.$compN))* }
    
      #[inline]
      fn approx_eq_eps(&self, other: &$t<N>, eps: &N) -> bool
      { self.$comp0.approx_eq_eps(&other.$comp0, eps) $(&& self.$compN.approx_eq_eps(&other.$compN, eps))* }
    }
  )
)

macro_rules! one_impl(
  ($t: ident) => (
    impl<N: Clone + One> One for $t<N>
    {
      #[inline]
      fn one() -> $t<N>
      { $t::new_repeat(One::one()) }
    }
  )
)

macro_rules! from_iterator_impl(
  ($t: ident, $param0: ident $(, $paramN: ident)*) => (
    impl<N, Iter: Iterator<N>> FromIterator<N, Iter> for $t<N>
    {
      fn from_iterator($param0: &mut Iter) -> $t<N>
      { $t::new($param0.next().unwrap() $(, $paramN.next().unwrap())*) }
    }
  )
)

macro_rules! bounded_impl(
  ($t: ident) => (
    impl<N: Bounded + Clone> Bounded for $t<N>
    {
      #[inline]
      fn max_value() -> $t<N>
      { $t::new_repeat(Bounded::max_value()) }
    
      #[inline]
      fn min_value() -> $t<N>
      { $t::new_repeat(Bounded::min_value()) }
    }
  )
)

macro_rules! to_homogeneous_impl(
  ($t: ident, $t2: ident, $extra: ident, $comp0: ident $(,$compN: ident)*) => (
    impl<N: Clone + One + Zero> ToHomogeneous<$t2<N>> for $t<N>
    {
      fn to_homogeneous(&self) -> $t2<N>
      {
        let mut res: $t2<N> = One::one();

        res.$comp0    = self.$comp0.clone();
        $( res.$compN = self.$compN.clone(); )*

        res
      }
    }
  )
)

macro_rules! from_homogeneous_impl(
  ($t: ident, $t2: ident, $extra: ident, $comp0: ident $(,$compN: ident)*) => (
    impl<N: Clone + Div<N, N> + One + Zero> FromHomogeneous<$t2<N>> for $t<N>
    {
      fn from(v: &$t2<N>) -> $t<N>
      {
        let mut res: $t<N> = Zero::zero();

        res.$comp0    = v.$comp0.clone();
        $( res.$compN = v.$compN.clone(); )*

        res.scalar_div(&v.$extra);

        res
      }
    }
  )
)