use na::{RealField, Unit};
use crate::math::{Isometry, Point, Translation, Vector};
use crate::query::algorithms::{
gjk, special_support_maps::ConstantOrigin, CSOPoint, VoronoiSimplex, EPA,
};
use crate::query::{PointProjection, PointQuery};
#[cfg(feature = "dim2")]
use crate::shape::ConvexPolygon;
#[cfg(feature = "dim3")]
use crate::shape::{Cone, ConvexHull, Cylinder};
use crate::shape::{ConvexPolyhedron, FeatureId, SupportMap};
pub fn point_projection_on_support_map<N, G>(
m: &Isometry<N>,
shape: &G,
simplex: &mut VoronoiSimplex<N>,
point: &Point<N>,
solid: bool,
) -> PointProjection<N>
where
N: RealField,
G: SupportMap<N>,
{
let id = Isometry::identity();
let m = Translation::from(-point.coords) * m;
let dir =
Unit::try_new(-m.translation.vector, N::default_epsilon()).unwrap_or(Vector::x_axis());
let support_point = CSOPoint::from_shapes(&m, shape, &id, &ConstantOrigin, &dir);
simplex.reset(support_point);
if let Some(proj) = gjk::project_origin(&m, shape, simplex) {
PointProjection::new(false, proj + point.coords)
} else if solid {
PointProjection::new(true, *point)
} else {
let mut epa = EPA::new();
if let Some(pt) = epa.project_origin(&m, shape, simplex) {
return PointProjection::new(true, pt + point.coords);
} else {
PointProjection::new(true, *point)
}
}
}
#[cfg(feature = "dim3")]
impl<N: RealField> PointQuery<N> for Cylinder<N> {
#[inline]
fn project_point(&self, m: &Isometry<N>, point: &Point<N>, solid: bool) -> PointProjection<N> {
point_projection_on_support_map(m, self, &mut VoronoiSimplex::new(), point, solid)
}
#[inline]
fn project_point_with_feature(
&self,
m: &Isometry<N>,
point: &Point<N>,
) -> (PointProjection<N>, FeatureId) {
(self.project_point(m, point, false), FeatureId::Unknown)
}
}
#[cfg(feature = "dim3")]
impl<N: RealField> PointQuery<N> for Cone<N> {
#[inline]
fn project_point(&self, m: &Isometry<N>, point: &Point<N>, solid: bool) -> PointProjection<N> {
point_projection_on_support_map(m, self, &mut VoronoiSimplex::new(), point, solid)
}
#[inline]
fn project_point_with_feature(
&self,
m: &Isometry<N>,
point: &Point<N>,
) -> (PointProjection<N>, FeatureId) {
(self.project_point(m, point, false), FeatureId::Unknown)
}
}
#[cfg(feature = "dim3")]
impl<N: RealField> PointQuery<N> for ConvexHull<N> {
#[inline]
fn project_point(&self, m: &Isometry<N>, point: &Point<N>, solid: bool) -> PointProjection<N> {
point_projection_on_support_map(m, self, &mut VoronoiSimplex::new(), point, solid)
}
#[inline]
fn project_point_with_feature(
&self,
m: &Isometry<N>,
point: &Point<N>,
) -> (PointProjection<N>, FeatureId) {
let proj = self.project_point(m, point, false);
let dpt = *point - proj.point;
let local_dir = if proj.is_inside {
m.inverse_transform_vector(&-dpt)
} else {
m.inverse_transform_vector(&dpt)
};
if let Some(local_dir) = Unit::try_new(local_dir, N::default_epsilon()) {
let feature = ConvexPolyhedron::<N>::support_feature_id_toward(self, &local_dir);
(proj, feature)
} else {
(proj, FeatureId::Unknown)
}
}
}
#[cfg(feature = "dim2")]
impl<N: RealField> PointQuery<N> for ConvexPolygon<N> {
#[inline]
fn project_point(&self, m: &Isometry<N>, point: &Point<N>, solid: bool) -> PointProjection<N> {
point_projection_on_support_map(m, self, &mut VoronoiSimplex::new(), point, solid)
}
#[inline]
fn project_point_with_feature(
&self,
m: &Isometry<N>,
point: &Point<N>,
) -> (PointProjection<N>, FeatureId) {
let proj = self.project_point(m, point, false);
let dpt = *point - proj.point;
let local_dir = if proj.is_inside {
m.inverse_transform_vector(&-dpt)
} else {
m.inverse_transform_vector(&dpt)
};
if let Some(local_dir) = Unit::try_new(local_dir, N::default_epsilon()) {
let feature = self.support_feature_id_toward(&local_dir);
(proj, feature)
} else {
(proj, FeatureId::Unknown)
}
}
}