#[cfg(test)]
mod test;
use crate::{
fem::block::element::{
ElementNodalEitherCoordinates, FRAC_1_SQRT_3, FiniteElement, ParametricCoordinate,
ParametricCoordinates, ParametricReference, ShapeFunctions, ShapeFunctionsGradients,
linear::{LinearElement, LinearFiniteElement, M},
},
math::{ScalarList, Tensor, TensorArray},
mechanics::Coordinate,
};
const G: usize = 8;
const N: usize = 8;
const P: usize = N;
const CORNERS: [[usize; 3]; N] = [
[1, 3, 4],
[2, 0, 5],
[3, 1, 6],
[0, 2, 7],
[7, 5, 0],
[4, 6, 1],
[5, 7, 2],
[6, 4, 3],
];
pub type Hexahedron = LinearElement<G, N>;
impl FiniteElement<G, M, N, P> for Hexahedron {
fn integration_points() -> ParametricCoordinates<G, M> {
[
[-FRAC_1_SQRT_3, -FRAC_1_SQRT_3, -FRAC_1_SQRT_3],
[-FRAC_1_SQRT_3, -FRAC_1_SQRT_3, FRAC_1_SQRT_3],
[-FRAC_1_SQRT_3, FRAC_1_SQRT_3, -FRAC_1_SQRT_3],
[-FRAC_1_SQRT_3, FRAC_1_SQRT_3, FRAC_1_SQRT_3],
[FRAC_1_SQRT_3, -FRAC_1_SQRT_3, -FRAC_1_SQRT_3],
[FRAC_1_SQRT_3, -FRAC_1_SQRT_3, FRAC_1_SQRT_3],
[FRAC_1_SQRT_3, FRAC_1_SQRT_3, -FRAC_1_SQRT_3],
[FRAC_1_SQRT_3, FRAC_1_SQRT_3, FRAC_1_SQRT_3],
]
.into()
}
fn integration_weights(&self) -> &ScalarList<G> {
&self.integration_weights
}
fn parametric_reference() -> ParametricReference<M, N> {
[
[-1.0, -1.0, -1.0],
[1.0, -1.0, -1.0],
[1.0, 1.0, -1.0],
[-1.0, 1.0, -1.0],
[-1.0, -1.0, 1.0],
[1.0, -1.0, 1.0],
[1.0, 1.0, 1.0],
[-1.0, 1.0, 1.0],
]
.into()
}
fn parametric_weights() -> ScalarList<G> {
[1.0; G].into()
}
fn scaled_jacobians<const I: usize>(
nodal_coordinates: ElementNodalEitherCoordinates<I, N>,
) -> ScalarList<P> {
let mut u = Coordinate::zero();
let mut v = Coordinate::zero();
let mut w = Coordinate::zero();
let mut n = Coordinate::zero();
CORNERS
.into_iter()
.enumerate()
.map(|(node, [node_a, node_b, node_c])| {
u = &nodal_coordinates[node_a] - &nodal_coordinates[node];
v = &nodal_coordinates[node_b] - &nodal_coordinates[node];
w = &nodal_coordinates[node_c] - &nodal_coordinates[node];
n = u.cross(&v);
(&n * &w) / u.norm() / v.norm() / w.norm()
})
.collect()
}
fn shape_functions(parametric_coordinate: ParametricCoordinate<M>) -> ShapeFunctions<N> {
let [xi_1, xi_2, xi_3] = parametric_coordinate.into();
[
(1.0 - xi_1) * (1.0 - xi_2) * (1.0 - xi_3) / 8.0,
(1.0 + xi_1) * (1.0 - xi_2) * (1.0 - xi_3) / 8.0,
(1.0 + xi_1) * (1.0 + xi_2) * (1.0 - xi_3) / 8.0,
(1.0 - xi_1) * (1.0 + xi_2) * (1.0 - xi_3) / 8.0,
(1.0 - xi_1) * (1.0 - xi_2) * (1.0 + xi_3) / 8.0,
(1.0 + xi_1) * (1.0 - xi_2) * (1.0 + xi_3) / 8.0,
(1.0 + xi_1) * (1.0 + xi_2) * (1.0 + xi_3) / 8.0,
(1.0 - xi_1) * (1.0 + xi_2) * (1.0 + xi_3) / 8.0,
]
.into()
}
fn shape_functions_gradients(
parametric_coordinate: ParametricCoordinate<M>,
) -> ShapeFunctionsGradients<M, N> {
let [xi_1, xi_2, xi_3] = parametric_coordinate.into();
[
[
-(1.0 - xi_2) * (1.0 - xi_3) / 8.0,
-(1.0 - xi_1) * (1.0 - xi_3) / 8.0,
-(1.0 - xi_1) * (1.0 - xi_2) / 8.0,
],
[
(1.0 - xi_2) * (1.0 - xi_3) / 8.0,
-(1.0 + xi_1) * (1.0 - xi_3) / 8.0,
-(1.0 + xi_1) * (1.0 - xi_2) / 8.0,
],
[
(1.0 + xi_2) * (1.0 - xi_3) / 8.0,
(1.0 + xi_1) * (1.0 - xi_3) / 8.0,
-(1.0 + xi_1) * (1.0 + xi_2) / 8.0,
],
[
-(1.0 + xi_2) * (1.0 - xi_3) / 8.0,
(1.0 - xi_1) * (1.0 - xi_3) / 8.0,
-(1.0 - xi_1) * (1.0 + xi_2) / 8.0,
],
[
-(1.0 - xi_2) * (1.0 + xi_3) / 8.0,
-(1.0 - xi_1) * (1.0 + xi_3) / 8.0,
(1.0 - xi_1) * (1.0 - xi_2) / 8.0,
],
[
(1.0 - xi_2) * (1.0 + xi_3) / 8.0,
-(1.0 + xi_1) * (1.0 + xi_3) / 8.0,
(1.0 + xi_1) * (1.0 - xi_2) / 8.0,
],
[
(1.0 + xi_2) * (1.0 + xi_3) / 8.0,
(1.0 + xi_1) * (1.0 + xi_3) / 8.0,
(1.0 + xi_1) * (1.0 + xi_2) / 8.0,
],
[
-(1.0 + xi_2) * (1.0 + xi_3) / 8.0,
(1.0 - xi_1) * (1.0 + xi_3) / 8.0,
(1.0 - xi_1) * (1.0 + xi_2) / 8.0,
],
]
.into()
}
}
impl LinearFiniteElement<G, N> for Hexahedron {}