SpaceEngine.cpp

00001 #include"SpaceEngine.h"
00002 
00003 SpaceEngine::SpaceEngine() //constructor of class SpaceEngine
00004 {
00005 }
00006 SpaceEngine::~SpaceEngine() //Destructor of class SpaceEngine
00007 {
00008 }
00009 
00010 
00011 // this function to initalise the objects of SpaceEngine class.
00012 void SpaceEngine::init(int x_spaceship,int y_spaceship, int x_bullet, int y_bullet,int fired_bullet, int x_alien,int y_alien, int speed_alien, int speed_bullet, int speed_spaceship)
00013 {
00014     _x_spaceship=x_spaceship; // represents the x-cooridante of the spaceship.
00015     _y_spaceship=y_spaceship; // represents the y-cooridante of the spaceship.
00016     _speed_spaceship=speed_spaceship; // speed of the spaceship.
00017     _x_bullet=x_bullet;  // represents the x-cooridante of the spaceship.
00018     _y_bullet=y_bullet;  // represents the y-cooridante of the spaceship.
00019     _fired_bullet= fired_bullet;  // spaceship fired the alien by relaseing the bullet.
00020     _x_alien= x_alien;  // represents the x-cooridante of the alien.
00021     _y_alien= y_alien;  // represents the y-cooridante of the spaceship.
00022     _speed_alien= speed_alien;  // speed of the alien.
00023     _speed_bullet=speed_bullet; // speed of the bullet.
00024 
00025     _bullet.init(_x_bullet, _y_bullet, speed_bullet,fired_bullet); // initalise the object bullet.
00026     _alien.init (_x_alien, _y_alien,_speed_alien);  // initalise the object  alien.
00027     _spaceship.init( _x_spaceship, _y_spaceship, _speed_spaceship);  // initalise the object  spaceship.
00028     _alien_killed = 0;  // set the killed alien at 0.
00029 }
00030 
00031 // void function for Gamepad library to read the position of the objects.
00032 void SpaceEngine::read_input(Gamepad &pad)
00033 {
00034     _d = pad.get_direction();
00035     _mag = pad.get_mag();
00036 }
00037 
00038 /**this function draw the objects on the screen
00039 *by using the (N5110 &lcd) libraries
00040 * if statment to check if the alien is alive so the lcd can draw it on the screen
00041 * else if statment will check if the alien dead so it should disappear
00042 *also it draws the spaceship
00043 */
00044 void  SpaceEngine::draw(N5110 &lcd)
00045 {
00046     _bullet.draw(lcd);
00047     if (_alien.isAlive() == true) {
00048         _alien.draw(lcd);
00049         // printf("alien is alive\n")
00050     } else { // alien is dead
00051         int y_pos = (rand() % 30) + 10; // random number 10 to 39
00052         _alien.init(70,y_pos,1);  //initalise the alien with its parameters.
00053         wait(0.2);//wait 0.2 sec
00054     }
00055     _spaceship.draw(lcd);
00056     lcd.printString("alien_killed",0,0);
00057     char kills[14];
00058     sprintf(kills,"%2d",_alien_killed);
00059     lcd.printString(kills,70,0);
00060 }
00061 
00062 /*
00063 *this void function for reading the the positions of the inputs(objects)by(Gamepad &pad)libraries in class SpaceEngine to detect the collisions.
00064 *this inculde if statment that shows when joystic's direction to the east the bullt will be fired.
00065 */
00066 void SpaceEngine::update(Gamepad &pad)
00067 {
00068     _bullet.update(_d,_mag);
00069     _alien.update(_d,_mag);
00070     _spaceship.update(_d,_mag);
00071     check_space_collision(pad);
00072     _y_alien = _alien.get_pos_y();
00073     _x_alien = _alien.get_pos_x();
00074     _y_bullet = _bullet.get_pos_y();
00075     _x_bullet = _bullet.get_pos_x();
00076     if(_d==E) {
00077         _fired_bullet=1;
00078         pad.tone(1000.0,0.1);
00079         // printf("bullet fired alien\n")
00080         _bullet.set_pos(_spaceship.get_pos_x()+33, _spaceship.get_pos_y());
00081     }
00082 }
00083 
00084 /*void function that checks the collision between the objects
00085 *if statment is to detect if x-coordinate of the bullet is larger or equal 65
00086 *and less than or equal to the 68 and if y-cooridante of the bullet is larger
00087 *than y-corrdindate of the alien-5 and y_alien+15 is larger or equal y_bullet
00088 *then the alien gets killed.
00089 */
00090 void SpaceEngine::check_space_collision(Gamepad &pad)
00091 {
00092     if(_x_bullet >= 65 && _x_bullet <= 68 && _y_bullet >= _y_alien-5 && _y_bullet <= _y_alien+15) {
00093         _alien.setAlive(false);
00094         // printf("alive alien false\n")
00095         _alien_killed++;
00096         // printf(" killed alien incremebt by 1\n")
00097     }
00098 }