How asteroids spawn

AsteroidSpawning.cpp

void SpacePlatform::spawnAsteroids()
{
  const bool randomOrientation = this->speed < 0.2;
  if (SpaceLocationID locationID = this->position.getCurrentLocation())
    for (auto& spawnDefinition : locationID->asteroidSpawnDefinitions)
      this->trySpawnAsteroid(spawnDefinition.asteroid, spawnDefinition.chunk, spawnDefinition, randomOrientation);
  else
  {
    const PointOnSpaceConnection& pointOnConnection = this->position.getPointOnConnection();
    for (auto& spawnDefinition : pointOnConnection.connection->asteroidSpawnDefinitions)
      this->trySpawnAsteroid(spawnDefinition.asteroid, spawnDefinition.asteroidChunk, spawnDefinition.interpolate(pointOnConnection.distance), randomOrientation);

    // Spawn SpaceLocation asteroids on space connections if the platform is in the location's sphere of influence.
    this->spawnAsteroidsOnConnectionNearEndPoint(**pointOnConnection.connection->from, pointOnConnection.distance);
    this->spawnAsteroidsOnConnectionNearEndPoint(**pointOnConnection.connection->to, 1 - pointOnConnection.distance);
  }
}

void SpacePlatform::spawnAsteroidsOnConnectionNearEndPoint(const SpaceLocationPrototype& endPoint, double distanceFromEndPoint)
{
  if (distanceFromEndPoint < endPoint.asteroidSpawnInfluence)
    for (const SpaceLocationAsteroidSpawnDefinition& spawnDefinition : endPoint.asteroidSpawnDefinitions)
      this->trySpawnAsteroid(spawnDefinition.asteroid,
                             spawnDefinition.chunk,
                             Math::lerp<AsteroidSpawnPoint>(spawnDefinition,
                                                            AsteroidSpawnPoint(0, 0, spawnDefinition.angleWhenStopped),
                                                            Math::inverseLerp(0.0, endPoint.asteroidSpawnInfluence, distanceFromEndPoint)),
                             !this->isMoving());
}

void SpacePlatform::trySpawnAsteroid(EntityID entityID, AsteroidChunkID asteroidChunkID, const AsteroidSpawnPoint& data, bool randomOrientation)
{
  static constexpr uint32_t BASE_SPAWNING_AREA = 1024;

  double probability = this->getAsteroidSpawningArea().getWidth().getDouble() + this->getAsteroidSpawningArea().getHeight().getDouble();
  if (!randomOrientation)
    probability += this->getAsteroidSpawningArea().getWidth().getDouble() * this->speed * 10;
  else if (!this->position.getCurrentLocation())
    probability *= 0.1; // Reduce asteroid spawning for platforms which stopped mid-route.
  probability *= *this->map.mapSettings->asteroidSettings.spawningRate / BASE_SPAWNING_AREA * data.probability;

  randomOrientation |= this->speed < UtilityConstants::instance().asteroidSpawningWithRandomOrientationMaxSpeed;
  for (; probability > 1; --probability)
    this->spawnAsteroid(entityID, asteroidChunkID, data, randomOrientation);
  if (this->map.getRandomGenerator().testChance(probability))
    this->spawnAsteroid(entityID, asteroidChunkID, data, randomOrientation);
}

SimpleBoundingBox SpacePlatform::getAsteroidSpawningArea()
{
  const SimpleBoundingBox& asteroidSpawningOffset = UtilityConstants::instance().asteroidSpawningOffset;
  return SimpleBoundingBox(this->platformBoundingBox.leftTop.x + asteroidSpawningOffset.leftTop.x,
                           this->platformBoundingBox.leftTop.y + asteroidSpawningOffset.leftTop.y,
                           this->platformBoundingBox.rightBottom.x + asteroidSpawningOffset.rightBottom.x,
                           this->platformBoundingBox.rightBottom.y + asteroidSpawningOffset.rightBottom.y);
}