Saucer.cpp

//
// Saucer.cpp
//

// Uncomment if Dragonfly uses STL instead of ObjectList.
//#define USE_STL

#include <stdlib.h>		// for rand()
#ifdef USE_STL
#include <vector>
#endif

// Engine includes.
#include "DisplayManager.h"
#include "EventCollision.h"
#include "EventNuke.h"
#include "EventOut.h"
#include "LogManager.h"
#include "WorldManager.h"
 
// Game includes.
#include "Explosion.h"
#include "Saucer.h"

Saucer::Saucer() {

  // Set object type.
  setType("Saucer");

  // Set speed in horizontal direction.
  setVelocity(df::Vector(-0.25,0)); // 1 space left every 4 frames

  moveToStart();

  // Register interest in "nuke" event.
#ifdef DF_REGISTER_INTEREST
  registerInterest(NUKE_EVENT);
#endif
}

// Handle event.
// Return 0 if ignored, else 1.
int Saucer::eventHandler(const df::Event *p_e) {

  if (p_e->getType() == df::OUT_EVENT) {
    out();
    return 1;
  }

  if (p_e->getType() == df::COLLISION_EVENT) {
    const df::EventCollision *p_collision_event = dynamic_cast <const df::EventCollision *> (p_e);
    hit(p_collision_event);
    return 1;
  }

  if (p_e->getType() == NUKE_EVENT) {
 
    // Create explosion.
    Explosion *p_explosion = new Explosion;
    p_explosion -> setPosition(this -> getPosition());
 
    // Delete self.
    WM.markForDelete(this);
 
    // Saucers appear stay around perpetually
    new Saucer;
  }
 
  // If get here, have ignored this event.
  return 0;
}

// If moved off left edge, move back to far right.
void Saucer::out() {

  // If haven't moved off left edge, then nothing to do.
  if (getPosition().getX() >= 0)
    return;

  // Otherwise, move back to far right.
  moveToStart();

  // Spawn new Saucer to make the game get harder.
  new Saucer;

}

// If saucer and player collide, mark both for deletion.
void Saucer::hit(const df::EventCollision *p_c) {

  // If Saucer on Saucer, ignore.
  if ((p_c -> getObject1() -> getType() == "Saucer") &&
      (p_c -> getObject2() -> getType() == "Saucer"))
    return;

  // If Bullet ...
  if ((p_c -> getObject1() -> getType() == "Bullet") ||
      (p_c -> getObject2() -> getType() == "Bullet")) {

    // Create an explosion.
    Explosion *p_explosion = new Explosion;
    p_explosion -> setPosition(this -> getPosition());

    // Saucers appear stay around perpetually.
    new Saucer;
  }

  // If Hero, mark both objects for destruction.
  if (((p_c -> getObject1() -> getType()) == "Hero") || 
      ((p_c -> getObject2() -> getType()) == "Hero")) {
    WM.markForDelete(p_c -> getObject1());
    WM.markForDelete(p_c -> getObject2());
  }

}

// Move saucer to starting location on right side of screen.
void Saucer::moveToStart() {
  df::Vector temp_pos;

  // Get world boundaries.
  int world_horiz = (int) DM.getHorizontal();
  int world_vert = (int) DM.getVertical();

  // x is off right side of screen.
  temp_pos.setX(world_horiz + rand()%world_horiz + 3.0f);

  // y is in vertical range.
  temp_pos.setY(rand()%(world_vert) + 0.0f);

  // If collision, move right slightly until empty space.
#ifdef USE_STL
  std::vector<Object *> collision_list = WM.getCollisions(this, temp_pos);
  while (collision_list.getCount() != 0) {
    temp_pos.setX(temp_pos.getX()+1.0f);
    collision_list = WM.getCollisions(this, temp_pos);
  }
#else
  df::ObjectList collision_list = WM.getCollisions(this, temp_pos);
  while (collision_list.getCount() != 0) {
    temp_pos.setX(temp_pos.getX()+1.0f);
    collision_list = WM.getCollisions(this, temp_pos);
  }
#endif  

  WM.moveObject(this, temp_pos);
}

int Saucer::draw() {
  DM.drawCh(getPosition(), SAUCER_CHAR, df::GREEN);
  return 0;
}