File size: 5,816 Bytes
9897e20
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
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
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
#pragma once

#include "binary_heap.hpp"
#include "types.hpp"
#include <algorithm>
#include <madrona/math.hpp>
#include <madrona/types.hpp>
#include "utils.hpp"

#ifndef MADRONA_GPU_MODE
#include <vector>
#endif

namespace {
bool cmp(const madrona_gpudrive::MapObservation &lhs, const madrona_gpudrive::MapObservation &rhs) {
  return lhs.position.length2() < rhs.position.length2();
}

void fillZeros(madrona_gpudrive::MapObservation *begin,
               madrona_gpudrive::MapObservation *beyond) {
  while (begin < beyond) {
    *begin++ =
        madrona_gpudrive::MapObservation{.position = {0, 0},
                                 .scale = madrona::math::Diag3x3{0, 0, 0},
                                 .heading = 0.f,
                                 .type = (float)madrona_gpudrive::EntityType::None};
  }
}

madrona_gpudrive::MapObservation
relativeObservation(const madrona_gpudrive::MapObservation &absoluteObservation,
                    const madrona::base::Rotation &referenceRotation,
                    const madrona::math::Vector2 &referencePosition) {
  auto relativePosition =
      madrona::math::Vector2{.x = absoluteObservation.position.x,
                             .y = absoluteObservation.position.y} -
      referencePosition;

  return madrona_gpudrive::MapObservation{
      .position = referenceRotation.inv()
                      .rotateVec({relativePosition.x, relativePosition.y, 0})
                      .xy(),
      .scale = absoluteObservation.scale,
      .heading =  madrona_gpudrive::utils::quatToYaw(referenceRotation.inv() * madrona::math::Quat::angleAxis(absoluteObservation.heading,madrona::math::up)),
      .type = absoluteObservation.type};
}


bool isObservationsValid(madrona_gpudrive::Engine &ctx,
                         madrona_gpudrive::MapObservation *observations,
                         madrona::CountT K,
                         const madrona::base::Rotation &referenceRotation,
                         const madrona::math::Vector2 &referencePosition) {
#ifdef MADRONA_GPU_MODE
  return true;
#else
  const auto roadCount = ctx.data().numRoads;

  std::vector<madrona_gpudrive::MapObservation> sortedObservations;
  sortedObservations.reserve(roadCount);

  for (madrona::CountT roadIdx = 0; roadIdx < roadCount; ++roadIdx) {
    auto &road_iface = ctx.get<madrona_gpudrive::RoadInterfaceEntity>(ctx.data().roads[roadIdx]).e;
    const auto &currentObservation =
        ctx.get<madrona_gpudrive::MapObservation>(road_iface);
    sortedObservations.emplace_back(relativeObservation(
        currentObservation, referenceRotation, referencePosition));
  }

  std::sort(sortedObservations.begin(), sortedObservations.end(), cmp);
  std::sort(observations, observations + K, cmp);

  return std::equal(observations, observations + K, sortedObservations.begin(),
                    sortedObservations.begin() + K,
                    [](const madrona_gpudrive::MapObservation &lhs,
                       const madrona_gpudrive::MapObservation &rhs) {
                      return lhs.position.x == rhs.position.x &&
                             lhs.position.y == rhs.position.y;
                    });
#endif
}

madrona::CountT radiusFilter(madrona_gpudrive::MapObservation *heap, madrona::CountT K, float radius) {
  madrona::CountT newBeyond{K};

  madrona::CountT idx{0};
  while (idx < newBeyond) {
    if (heap[idx].position.length() <= radius) {
      ++idx;
      continue;
    }

    heap[idx] = heap[--newBeyond];
  }

  return newBeyond;
}

} // namespace

namespace madrona_gpudrive {

template <madrona::CountT K>
void selectKNearestRoadEntities(Engine &ctx, const Rotation &referenceRotation,
                                const madrona::math::Vector2 &referencePosition,
                                madrona_gpudrive::MapObservation *heap) {
  const Entity *roads = ctx.data().roads;
  const auto roadCount = ctx.data().numRoads;

  utils::ReferenceFrame referenceFrame(referencePosition, referenceRotation);

  for (madrona::CountT i = 0; i < std::min(roadCount, K); ++i) {
    heap[i] =
        referenceFrame.observationOf(ctx.get<madrona::base::Position>(roads[i]),
                                     ctx.get<madrona::base::Rotation>(roads[i]),
                                     ctx.get<madrona::base::Scale>(roads[i]),
                                     ctx.get<madrona_gpudrive::EntityType>(roads[i]),
                                     static_cast<float>(ctx.get<RoadMapId>(roads[i]).id),
                                     ctx.get<MapType>(roads[i]));
  }

  if (roadCount < K) {
    auto newBeyond = radiusFilter(heap, roadCount, ctx.data().params.observationRadius);
    fillZeros(heap + newBeyond, heap + K);
    return;
  }

  make_heap(heap, heap + K, cmp);

  for (madrona::CountT roadIdx = K; roadIdx < roadCount; ++roadIdx) {
    auto currentObservation = referenceFrame.observationOf(
        ctx.get<madrona::base::Position>(roads[roadIdx]),
        ctx.get<madrona::base::Rotation>(roads[roadIdx]),
        ctx.get<madrona::base::Scale>(roads[roadIdx]),
        ctx.get<madrona_gpudrive::EntityType>(roads[roadIdx]),
        static_cast<float>(ctx.get<RoadMapId>(roads[roadIdx]).id),
        ctx.get<MapType>(roads[roadIdx]));

    const auto &kthNearestObservation = heap[0];
    bool isCurrentObservationCloser =
        cmp(currentObservation, kthNearestObservation);

    if (not isCurrentObservationCloser) {
      continue;
    }

    pop_heap(heap, heap + K, cmp);

    heap[K - 1] = currentObservation;
    push_heap(heap, heap + K, cmp);
  }

  assert(
      isObservationsValid(ctx, heap, K, referenceRotation, referencePosition));

  auto newBeyond = radiusFilter(heap, K, ctx.data().params.observationRadius);
  fillZeros(heap + newBeyond, heap + K);
}

} // namespace madrona_gpudrive