1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132

use crate::bounding_volume::AABB;
use crate::math::{Isometry, Point, Vector};
use crate::partitioning::{BestFirstVisitStatus, BestFirstVisitor};
use crate::query::{self, ClosestPoints, PointQuery};
use crate::shape::{CompositeShape, Shape};
use na::{self, RealField};

/// Closest points between a composite shape and any other shape.
pub fn closest_points_composite_shape_shape<N, G1: ?Sized>(
    m1: &Isometry<N>,
    g1: &G1,
    m2: &Isometry<N>,
    g2: &dyn Shape<N>,
    margin: N,
) -> ClosestPoints<N>
where
    N: RealField,
    G1: CompositeShape<N>,
{
    let mut visitor = CompositeShapeAgainstShapeClosestPointsVisitor::new(m1, g1, m2, g2, margin);

    g1.bvh()
        .best_first_search(&mut visitor)
        .expect("The composite shape must not be empty.")
        .1
}

/// Closest points between a shape and a composite shape.
pub fn closest_points_shape_composite_shape<N, G2: ?Sized>(
    m1: &Isometry<N>,
    g1: &dyn Shape<N>,
    m2: &Isometry<N>,
    g2: &G2,
    margin: N,
) -> ClosestPoints<N>
where
    N: RealField,
    G2: CompositeShape<N>,
{
    let mut res = closest_points_composite_shape_shape(m2, g2, m1, g1, margin);
    res.flip();
    res
}

struct CompositeShapeAgainstShapeClosestPointsVisitor<'a, N: 'a + RealField, G1: ?Sized + 'a> {
    msum_shift: Vector<N>,
    msum_margin: Vector<N>,
    margin: N,

    m1: &'a Isometry<N>,
    g1: &'a G1,
    m2: &'a Isometry<N>,
    g2: &'a dyn Shape<N>,
}

impl<'a, N, G1: ?Sized> CompositeShapeAgainstShapeClosestPointsVisitor<'a, N, G1>
where
    N: RealField,
    G1: CompositeShape<N>,
{
    pub fn new(
        m1: &'a Isometry<N>,
        g1: &'a G1,
        m2: &'a Isometry<N>,
        g2: &'a dyn Shape<N>,
        margin: N,
    ) -> CompositeShapeAgainstShapeClosestPointsVisitor<'a, N, G1> {
        let ls_m2 = m1.inverse() * m2.clone();
        let ls_aabb2 = g2.aabb(&ls_m2);

        CompositeShapeAgainstShapeClosestPointsVisitor {
            msum_shift: -ls_aabb2.center().coords,
            msum_margin: ls_aabb2.half_extents(),
            margin: margin,
            m1: m1,
            g1: g1,
            m2: m2,
            g2: g2,
        }
    }
}

impl<'a, N, G1: ?Sized> BestFirstVisitor<N, usize, AABB<N>>
    for CompositeShapeAgainstShapeClosestPointsVisitor<'a, N, G1>
where
    N: RealField,
    G1: CompositeShape<N>,
{
    type Result = ClosestPoints<N>;

    fn visit(
        &mut self,
        best: N,
        bv: &AABB<N>,
        data: Option<&usize>,
    ) -> BestFirstVisitStatus<N, Self::Result> {
        // Compute the minkowski sum of the two AABBs.
        let msum = AABB::new(
            bv.mins + self.msum_shift + (-self.msum_margin),
            bv.maxs + self.msum_shift + self.msum_margin,
        );

        let dist = msum.distance_to_point(&Isometry::identity(), &Point::origin(), true);

        let mut res = BestFirstVisitStatus::Continue {
            cost: dist,
            result: None,
        };

        if let Some(b) = data {
            if dist < best {
                self.g1.map_part_at(*b, self.m1, &mut |m1, g1| {
                    let pts = query::closest_points(m1, g1, self.m2, self.g2, self.margin);
                    match pts {
                        ClosestPoints::WithinMargin(ref p1, ref p2) => {
                            res = BestFirstVisitStatus::Continue {
                                cost: na::distance(p1, p2),
                                result: Some(pts),
                            }
                        }
                        ClosestPoints::Intersecting => {
                            res = BestFirstVisitStatus::ExitEarly(Some(pts))
                        }
                        ClosestPoints::Disjoint => {}
                    };
                });
            }
        }

        res
    }
}