it.unibo.alchemist.model.cognitive.actions.CognitiveAgentAvoidLayer.kt Maven / Gradle / Ivy

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Abstraction for group of pedestrians capable of influence each other emotionally.
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/*
 * Copyright (C) 2010-2023, Danilo Pianini and contributors
 * listed, for each module, in the respective subproject's build.gradle.kts file.
 *
 * This file is part of Alchemist, and is distributed under the terms of the
 * GNU General Public License, with a linking exception,
 * as described in the file LICENSE in the Alchemist distribution's top directory.
 */

package it.unibo.alchemist.model.cognitive.actions

import it.unibo.alchemist.model.EnvironmentWithObstacles
import it.unibo.alchemist.model.Molecule
import it.unibo.alchemist.model.Node
import it.unibo.alchemist.model.Node.Companion.asPropertyOrNull
import it.unibo.alchemist.model.Reaction
import it.unibo.alchemist.model.cognitive.CognitiveProperty
import it.unibo.alchemist.model.cognitive.PedestrianProperty
import it.unibo.alchemist.model.environments.Euclidean2DEnvironment
import it.unibo.alchemist.model.positions.Euclidean2DPosition

/**
 * Move the node towards positions of the environment with a low concentration of the target molecule.
 *
 * @param environment
 *          the environment inside which the node moves.
 * @param reaction
 *          the reaction which executes this action.
 * @param pedestrian
 *          the owner of this action.
 * @param targetMolecule
 *          the {@link Molecule} you want to know the concentration in the different positions of the environment.
 * @param viewDepth
 *          the depth of view of the node, defaults to infinity.
 */
class CognitiveAgentAvoidLayer @JvmOverloads constructor(
    environment: Euclidean2DEnvironment,
    reaction: Reaction,
    override val pedestrian: PedestrianProperty,
    targetMolecule: Molecule,
    private val viewDepth: Double = Double.POSITIVE_INFINITY,
) : AbstractLayerAction(environment, reaction, pedestrian, targetMolecule) {

    private val followScalarField = getLayerOrFail().let { layer ->
        CognitiveAgentFollowScalarField(environment, reaction, pedestrian, layer.center()) {
            /*
             * Moves the node where the concentration is lower.
             */
            -layer.concentrationIn(it)
        }
    }

    override fun cloneAction(node: Node, reaction: Reaction): CognitiveAgentAvoidLayer =
        CognitiveAgentAvoidLayer(environment, reaction, node.pedestrianProperty, targetMolecule, viewDepth)

    /**
     * @returns the next relative position. The node is moved only if he/she percepts the danger
     * (either because it is in sight or due to social contagion), otherwise a zero vector is returned.
     */
    override fun nextPosition(): Euclidean2DPosition = when {
        node.wantsToEscape() || isDangerInSight() -> followScalarField.nextPosition()
        else -> environment.origin
    }

    /**
     * Checks whether the center of the layer (if there's one) is in sight. If the layer has no center true is
     * returned.
     */
    @Suppress("UNCHECKED_CAST")
    private fun isDangerInSight(): Boolean = getLayerOrFail().center()?.let { center ->
        val currentPosition = environment.getPosition(node)
        /*
         * environment is euclidean, so if it has obstacles it must be an
         * EnvironmentWithObstacles<*, *, Euclidean2DPosition>. Since generic types can't be checked at runtime, this
         * is the best we can do.
         */
        val visualTrajectoryOccluded = (environment as? EnvironmentWithObstacles<*, *, Euclidean2DPosition>)
            ?.intersectsObstacle(currentPosition, center)
            ?: false
        center.distanceTo(currentPosition) <= viewDepth && !visualTrajectoryOccluded
    } ?: true

    private fun  Node.wantsToEscape(): Boolean {
        val cognitiveProperty = asPropertyOrNull>()
        return cognitiveProperty != null &&
            cognitiveProperty.danger == targetMolecule &&
            cognitiveProperty.cognitiveModel.wantsToEscape()
    }
}