use crate::kernel::Kernel;
use crate::math::Real;
use na::RealField;
#[derive(Copy, Clone, Debug)]
pub struct Poly6Kernel;
impl Kernel for Poly6Kernel {
fn scalar_apply(r: Real, h: Real) -> Real {
assert!(r >= na::zero::<Real>());
#[cfg(feature = "dim2")]
let normalizer = na::convert::<_, Real>(4.0) / (Real::pi() * h.powi(8));
#[cfg(feature = "dim3")]
let normalizer = na::convert::<_, Real>(315.0 / 64.0) / (Real::pi() * h.powi(9));
if r <= h {
normalizer * (h * h - r * r).powi(3)
} else {
na::zero::<Real>()
}
}
fn scalar_apply_diff(r: Real, h: Real) -> Real {
assert!(r >= na::zero::<Real>());
#[cfg(feature = "dim2")]
let normalizer = na::convert::<_, Real>(4.0) / (Real::pi() * h.powi(8));
#[cfg(feature = "dim3")]
let normalizer = na::convert::<_, Real>(315.0 / 64.0) / (Real::pi() * h.powi(9));
if r <= h {
normalizer * (h * h - r * r).powi(2) * r * na::convert::<_, Real>(-6.0)
} else {
na::zero::<Real>()
}
}
}