RoboidControl-cpp/Perception.cpp

#include "Perception.h"
#include "Angle.h"
#include "DistanceSensor.h"
#include "NetworkSync.h"
#include "Switch.h"

#include <math.h>

Perception::Perception() {
  for (unsigned char objIx = 0; objIx < maxObjectCount; objIx++)
    this->perceivedObjects[objIx] = nullptr;
}

Perception::Perception(Placement *sensors, unsigned int sensorCount)
    : Perception() {
  this->sensorCount = sensorCount;
  this->sensorPlacements = (Placement *)sensors;
}

unsigned int Perception::GetSensorCount() { return this->sensorCount; }

Sensor *Perception::GetSensor(unsigned int sensorId) {
  if (sensorId >= this->sensorCount)
    return nullptr;

  Thing *thing = this->sensorPlacements[sensorId].thing;
  if (thing->IsSensor())
    return (Sensor *)thing;

  return nullptr;
}

Sensor *Perception::FindSensorOfType(unsigned int sensorType) {
  for (unsigned int sensorIx = 0; sensorIx < this->sensorCount; sensorIx++) {
    Sensor *sensor = (Sensor *)this->sensorPlacements[sensorIx].thing;
    if (sensor->type == sensorType)
      return sensor;
  }

  return nullptr;
}

float Perception::GetDistance(float direction, float range) {
  float minDistance = INFINITY;
  if (range < 0)
    range = -range;

  for (unsigned char objIx = 0; objIx < maxObjectCount; objIx++) {
    PerceivedObject *obj = perceivedObjects[objIx];
    if (obj == nullptr)
      continue;
    if (obj->position.angle > direction - range &&
        obj->position.angle < direction + range) {

      minDistance = fmin(minDistance, obj->position.distance);
    }
  }
  return minDistance;
}

float Perception::GetDistance(float horizontalDirection,
                              float verticalDirection, float range) {
  float minDistance = INFINITY;
  if (range < 0)
    range = -range;

  for (unsigned char objIx = 0; objIx < maxObjectCount; objIx++) {
    PerceivedObject *obj = perceivedObjects[objIx];
    if (obj == nullptr)
      continue;
    if (obj->position.angle > horizontalDirection - range &&
        obj->position.angle < horizontalDirection + range) {

      minDistance = fmin(minDistance, obj->position.distance);
    }
  }

  return minDistance;
}
bool Perception::ObjectNearby(float direction, float range) {
  if (range < 0)
    range = -range;

  for (unsigned char objIx = 0; objIx < maxObjectCount; objIx++) {
    PerceivedObject *obj = perceivedObjects[objIx];
    if (obj == nullptr)
      continue;

    if (obj->position.angle > direction - range &&
        obj->position.angle < direction + range) {
      if (obj->position.distance <= nearbyDistance)
        return true;
    }
  }
  return false;
}

/***
 * Oject perception
 ***/

PerceivedObject::PerceivedObject() {
  this->id = 0;
  this->confidence = maxConfidence;
  this->position = Polar(0, INFINITY);
  this->radius = INFINITY;
}

PerceivedObject::PerceivedObject(Sensor *sensor, Polar position, float radius)
    : PerceivedObject() {
  this->sensor = sensor;
  this->position = position;
  this->radius = radius;
}

bool PerceivedObject::IsTheSameAs(PerceivedObject *otherObj) {
  if (id != 0 && id == otherObj->id)
    return true;
  if (abs(position.distance - otherObj->position.distance) > equalityDistance)
    return false;
  if (abs(position.angle - otherObj->position.angle) > equalityAngle)
    return false;
  return true;
}

bool PerceivedObject::DegradeConfidence(float deltaTime) {
  unsigned char confidenceDrop =
      (unsigned char)((float)confidenceDropSpeed * deltaTime);
  // Make sure the confidence always drops
  if (confidenceDrop == 0)
    confidenceDrop = 1;

  if (confidence <= confidenceDrop) {
    // object is dead
    confidence = 0;
    return false;
  } else {
    confidence -= confidenceDrop;
    return true;
  }
}

void PerceivedObject::Refresh(Polar position, float radius) {
  this->position = position;
  this->radius = radius;
  this->confidence = maxConfidence;
}

void Perception::AddPerceivedObject(Sensor *sensor, Polar position) {
  // int objCount = PerceivedObjectCount();
  // printf("perc obj count %d\n");

  PerceivedObject *obj = new PerceivedObject(sensor, position);
  // objCount = PerceivedObjectCount();
  // printf("perc obj count %d\n");
  //   AddPerceivedObject(obj);
  // }

  // void Perception::AddPerceivedObject(PerceivedObject *obj) {
  unsigned char farthestObjIx = 0;
  unsigned char availableSlotIx = 0;
  for (unsigned char objIx = 0; objIx < maxObjectCount; objIx++) {
    // printf("[%d] %d\n", objIx, this->perceivedObjects[objIx]);
    // Is this slot available?
    if (this->perceivedObjects[objIx] == nullptr) {
      availableSlotIx = objIx;
    }
    // Do we see the same object?
    else {
      // printf("(%d) my %f %f =^= received %f %f\n", objIx,
      //        this->perceivedObjects[objIx]->position.distance,
      //        this->perceivedObjects[objIx]->position.angle,
      //        obj->position.distance, obj->position.angle);
      if (obj->IsTheSameAs(this->perceivedObjects[objIx])) {
        // printf("[%d] Updating...\n", objIx);
        this->perceivedObjects[objIx]->Refresh(obj->position, obj->radius);
        return;
      }
      // Is this the fartest object we see?
      else if (this->perceivedObjects[farthestObjIx] == nullptr ||
               (this->perceivedObjects[objIx]->position.distance >
                this->perceivedObjects[farthestObjIx]->position.distance)) {
        farthestObjIx = objIx;
      }
    }
  }

  // Check if an perception slot is available (we currently see less than the
  // max number of objects)
  if (availableSlotIx < maxObjectCount) {
    // a slot is available
    // printf("[%d] new object \n", availableSlotIx);
    this->perceivedObjects[availableSlotIx] = obj;
  }
  // If this object is closer than the farthest object, then replace it
  else if (obj->position.distance <
           this->perceivedObjects[farthestObjIx]->position.distance) {
    this->perceivedObjects[farthestObjIx] = obj;
    // we may want to destroy the fartest object, but if it is created
    // externally, other links may still exist...
  }
}

unsigned char Perception::PerceivedObjectCount() {
  unsigned char objectCount = 0;
  for (unsigned char objIx = 0; objIx < maxObjectCount; objIx++) {
    if (this->perceivedObjects[objIx] != nullptr)
      objectCount++;
  }
  return objectCount;
}

PerceivedObject **Perception::GetPerceivedObjects() {
  return this->perceivedObjects;
}

void Perception::Update(float currentTimeMs) {
  float deltaTime = currentTimeMs - lastUpdateTimeMs;
  if (deltaTime <= 0)
    return;

  lastUpdateTimeMs = currentTimeMs;

  // Update sensing
  for (unsigned int sensorIx = 0; sensorIx < this->sensorCount; sensorIx++) {
    Placement thingPlacement = sensorPlacements[sensorIx];
    Thing *thing = thingPlacement.thing;
    if (thing == nullptr)
      continue;

    if (thing->type == Thing::DistanceSensorType) {
      DistanceSensor *distanceSensor = (DistanceSensor *)thing;

      float distance = distanceSensor->GetDistance();
      float angle = thingPlacement.horizontalDirection;
      Polar position = Polar(angle, distance);
      AddPerceivedObject(distanceSensor, position);
    } else if (thing->type == Thing::SwitchType) {
      Switch *switchSensor = (Switch *)thing;
      if (switchSensor != nullptr && switchSensor->IsOn()) {
        Polar position =
            Polar(thingPlacement.horizontalDirection, nearbyDistance);
        AddPerceivedObject(switchSensor, position);
      }
    }
  }

  for (unsigned char objIx = 0; objIx < maxObjectCount; objIx++) {
    PerceivedObject *obj = perceivedObjects[objIx];
    if (obj == nullptr)
      continue;

    if (obj->DegradeConfidence(deltaTime) == false) {
      // delete obj
      // printf("[%d] delete object\n", objIx);
      if (roboid != nullptr && roboid->networkSync != nullptr)
        roboid->networkSync->DestroyObject(obj);
      this->perceivedObjects[objIx] = nullptr;
      // } else {
      //   Serial.printf("[%d] confidence: %d\n", objIx,
      //                 this->perceivedObjects[objIx]->confidence);
    }
  }
  if (this->perceivedObjects[0] != nullptr) {
  }
}

void Perception::UpdatePose(Polar translation) {
  for (unsigned char objIx = 0; objIx < maxObjectCount; objIx++) {
    PerceivedObject *obj = perceivedObjects[objIx];
    if (obj == nullptr)
      continue;

    Polar newPosition = obj->position - translation;
    obj->position = newPosition;
  }
}

void Perception::UpdatePose(Quaternion rotation) {
  // only rotation around vertical axis is supported for now
  float rotationAngle;
  Vector3 rotationAxis;
  rotation.ToAngleAxis(&rotationAngle, &rotationAxis);
  // Make sure rotation axis is positive
  if (rotationAxis.y < 0)
    rotationAngle = -rotationAngle;

  for (unsigned char objIx = 0; objIx < maxObjectCount; objIx++) {
    PerceivedObject *obj = perceivedObjects[objIx];
    if (obj == nullptr)
      continue;

    float updatedAngle = Angle::Normalize(obj->position.angle - rotationAngle);
    obj->position.angle = updatedAngle;
  }
}