/**
 * this sketch illustrates how we designed the creatures 'hysteria'.
 * they are dangerous, very small, and live in swarms in the water.
 */


import gestalt.Gestalt;
import gestalt.p5.GestaltPlugIn;
import gestalt.shape.Mesh;

import mathematik.Vector3f;

import verhalten.Engine;
import verhalten.Wander;

import processing.opengl.*;


public class Hysteria
extends PApplet {

  private GestaltPlugIn gestalt;

  private HysteriaEntity[] _myEntities;

  private Mesh _myMesh;

  private float[] _myVertices;

  private float[] _myColor;

  public void setup() {
    /* setup p5 */
    size(640, 480, OPENGL);
    framerate(50);
    rectMode(CENTER);
    noStroke();

    gestalt = new GestaltPlugIn(this);

    /* g1 */
    gestalt.camera().fovy = 25f;
    gestalt.camera().setMode(Gestalt.CAMERA_MODE_LOOK_AT);

    int myNumberOfEntities = 150;
    _myVertices = new float[myNumberOfEntities * 3];
    _myColor = new float[myNumberOfEntities * 4];

    /* create mesh */
    _myMesh = gestalt.drawablefactory().mesh(false,
    _myVertices, 3,
    _myColor, 4,
    null, 2,
    null,
    Gestalt.MESH_TRIANGLES);
    _myMesh.material().wireframe = false;
    _myMesh.material().transparent = true;
    _myMesh.material().getColor().r = 0.75f;
    _myMesh.material().getColor().g = 1.0f;
    _myMesh.material().getColor().b = 0.1f;
    _myMesh.material().getColor().a = 0.05f;
    _myMesh.material().blendmode = Gestalt.MATERIAL_BLEND_INVERS_MULTIPLY;
    _myMesh.material().depthtest = false;
    gestalt.bin(Gestalt.BIN_3D).add(_myMesh);

    /* create entites */
    _myEntities = new HysteriaEntity[myNumberOfEntities];
    for (int i = 0; i < _myEntities.length; i++) {
      _myEntities[i] = new HysteriaEntity(i, _myMesh);
    }
  }


  public void draw() {
    /* clear screen */
    background(50);

    /* change shape */
    if (keyPressed) {
      if (key == '1') {
        _myMesh.setPrimitive(Gestalt.MESH_LINE_LOOP);
      }
      if (key == '2') {
        _myMesh.setPrimitive(Gestalt.MESH_POINTS);
      }
      if (key == '3') {
        _myMesh.setPrimitive(Gestalt.MESH_POLYGON);
      }
      if (key == '4') {
        _myMesh.setPrimitive(Gestalt.MESH_QUAD_STRIP);
      }
      if (key == '5') {
        _myMesh.setPrimitive(Gestalt.MESH_QUADS);
      }
      if (key == '6') {
        _myMesh.setPrimitive(Gestalt.MESH_TRIANGLES);
      }
    }

    /* update entities */
    for (int i = 0; i < _myEntities.length; i++) {
      _myEntities[i].loop(1 / 50f);
      final float myOffset = random(0, 1) * 2;
      _myEntities[i].position().x += random(0, 1) * myOffset - myOffset / 2;
      _myEntities[i].position().y += random(0, 1) * myOffset - myOffset / 2;
    }
  }


  private class HysteriaEntity {

    private static final float ourConstraint = 200;

    private Engine _myWanderEngine;

    private Wander _myWander;

    private Mesh _myGroupView;

    private int _myPositionIndex;

    public HysteriaEntity(int thePositionIndex,
    Mesh theGroupView) {

      _myGroupView = theGroupView;
      _myPositionIndex = thePositionIndex;

      /* setup an engine */
      _myWanderEngine = new Engine();
      _myWanderEngine.velocity().set(10, 0, 0);

      /* setup behavior */
      _myWander = new Wander();
      _myWander.possibleDirections().z = 0;
    }


    public Vector3f position() {
      return _myWanderEngine.position();
    }


    public void loop(float theDeltaTime) {
      /* wander */
      Vector3f myArriveDirection = new Vector3f();
      _myWander.get(_myWanderEngine, theDeltaTime, myArriveDirection);
      _myWanderEngine.apply(theDeltaTime, myArriveDirection);

      if (mousePressed) {
        _myWanderEngine.setMaximumForce(60.0f);
        _myWanderEngine.setMaximumSpeed(50.0f);
      } 
      else {
        _myWanderEngine.setMaximumForce(12.0f);
        _myWanderEngine.setMaximumSpeed(10.0f);
      }

      /* teleport */
      if (_myWanderEngine.position().length() > ourConstraint / 2) {
        _myWanderEngine.position().set(random(0, 1) * ourConstraint - ourConstraint / 2,
        random(0, 1) * ourConstraint - ourConstraint / 2,
        0);
      }

      /* update arrays */
      _myGroupView.vertices()[_myPositionIndex * 3 + 0] = _myWanderEngine.position().x;
      _myGroupView.vertices()[_myPositionIndex * 3 + 1] = _myWanderEngine.position().y;
      _myGroupView.vertices()[_myPositionIndex * 3 + 2] = _myWanderEngine.position().z;
      _myGroupView.colors()[_myPositionIndex * 4 + 0] = 0.75f;
      _myGroupView.colors()[_myPositionIndex * 4 + 1] = 1;
      _myGroupView.colors()[_myPositionIndex * 4 + 2] = 0.1f;
      float myDistance = _myWanderEngine.position().length() / (ourConstraint / 2);
      _myGroupView.colors()[_myPositionIndex * 4 + 3] = 0.25f * (1 - pow(myDistance, 0.25f));
    }
  }


  public static void main(String[] args) {
    PApplet.main(new String[] {
      "Hysteria"    }
    );
  }
}