/*
   orxonox - the future of 3D-vertical-scrollers

   Copyright (C) 2004 orx

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2, or (at your option)
   any later version.

   ### File Specific:
   main-programmer: Benjamin Grauer
   co-programmer: Patrick Boenzli
*/

#define DEBUG_SPECIAL_MODULE DEBUG_MODULE_GRAPHICS

#include "plane_emitter.h"

#include "particle_system.h"

#include "util/loading/load_param.h"
#include "util/loading/factory.h"
#include "debug.h"



ObjectListDefinition(PlaneEmitter);
CREATE_FACTORY(PlaneEmitter);

/**
 *  standard constructor
*/
PlaneEmitter::PlaneEmitter(const Vector2D& size, float emissionRate, float velocity, float angle)
    :  ParticleEmitter(emissionRate, velocity, angle)
{
  this->init();
  this->setSize(size);
}

/**
 *  constructs and loads a PlaneEmitter from a XML-element
 * @param root the XML-element to load from
*/
PlaneEmitter::PlaneEmitter(const TiXmlElement* root)
    : ParticleEmitter()
{
  this->init();

  if (root != NULL)
    this->loadParams(root);
}

/**
 *  standard destructor

   removes the EmitterSystem from the ParticleEngine
*/
PlaneEmitter::~PlaneEmitter ()
{
  this->setSystem(NULL);
}

/**
  @brief initializes default values of a ParitcleEmitter
*/
void PlaneEmitter::init()
{
  this->registerObject(this, PlaneEmitter::_objectList);
  this->setSize(1.0f, 1.0f);
}

void PlaneEmitter::loadParams(const TiXmlElement* root)
{
  ParticleEmitter::loadParams(root);

  LoadParam(root, "size", this, PlaneEmitter, setSize)
  .describe("The Size of the PlaneEmitter: x, y")
  .defaultValues(1.0f,1.0f);
}

void PlaneEmitter::setSize(float x, float y)
{
  this->size = Vector2D(x, y);
}


void PlaneEmitter::emitParticles(unsigned int count) const
{
  Vector inheritVelocity = this->getVelocity() * this->inheritSpeed;

  Vector xDir = this->getAbsDirX() * this->size.x;
  Vector yDir = this->getAbsDirZ() * this->size.y;
  Vector zDir = this->getAbsDirY();

  for (unsigned int i = 0; i < count; i++)
  {
    Vector randDir = Vector(rand()-RAND_MAX/2, rand()-RAND_MAX/2, rand()-RAND_MAX/2);
    randDir.normalize();
    randDir = (Quaternion(angle + randomAngle *((float)rand()/RAND_MAX -.5), randDir)).apply(zDir);
    Vector velocityV = randDir.getNormalized()*this->velocity + inheritVelocity;

    Vector plane = this->getAbsCoor() +
        xDir * ((float)rand()/RAND_MAX -.5) +
        yDir * ((float)rand()/RAND_MAX -.5);

    // ROTATIONAL CALCULATION (this must not be done for all types of particles.)
    randDir = Vector(rand()-RAND_MAX/2, rand()-RAND_MAX/2, rand()-RAND_MAX/2);
    randDir.normalize();
    Quaternion orient = Quaternion(M_PI, randDir);
    Quaternion moment = Quaternion(this->momentum + this->momentumRandom, randDir);

    this->getSystem()->addParticle(plane, velocityV, orient, moment, extForce);

  }
}