powerup.java

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    //--------------------------------- REVISIONS ------------------------------
    // Date       Name                 Tracking #         Description
    // ---------  -------------------  -------------      ----------------------
    // 18JAN2008  James Shen                 	          Initial Creation 
    ////////////////////////////////////////////////////////////////////////////
    /**
     * Check if bullet hit Player's home,if so, display the destoryed home.
     */
    public static boolean isHomeDestroyed(){
        boolean bRet=false;
        for(int i=1;i<POOL_SIZE;i++){
            if(POWERUP_POOL[i].isVisible() &&
                   POWERUP_POOL[i].getType()==Powerup.HOME_DESTROYED ){
                bRet=true;
                break;
            }
        }
        return bRet;
    }
    ////////////////////////////////////////////////////////////////////////////
    //--------------------------------- REVISIONS ------------------------------
    // Date       Name                 Tracking #         Description
    // ---------  -------------------  -------------      ----------------------
    // 18JAN2008  James Shen                 	          Initial Creation 
    ////////////////////////////////////////////////////////////////////////////
    /**
     * Check if bullet hit Player's home,if so, display the destoryed home.
     */
    public static boolean isHittingHome(Bullet bullet){
        boolean bRet=false;
        Powerup home=null;
        for(int i=1;i<POOL_SIZE;i++){
            if(POWERUP_POOL[i].isVisible() &&
                   POWERUP_POOL[i].getType()==Powerup.HOME ){
                home=POWERUP_POOL[i];
            }
        }
        if(home!=null){
            bRet=bullet.collidesWith(home,false);
            if(bRet){
                home.setType(Powerup.HOME_DESTROYED);
            }
        }
        return bRet;
    }
    
    ////////////////////////////////////////////////////////////////////////////
    //--------------------------------- REVISIONS ------------------------------
    // Date       Name                 Tracking #         Description
    // ---------  -------------------  -------------      ----------------------
    // 17JAN2008  James Shen                 	          Initial Creation 
    ////////////////////////////////////////////////////////////////////////////
    /**
     * Create a new power up in the battle field.
     * @param type the type of the powerup.
     */
    public static void putNewPowerup(int type){
        for(int i=1;i<POOL_SIZE;i++){
            if(!POWERUP_POOL[i].isVisible()){
                POWERUP_POOL[i].setType(type);
                battleField.initPowerupPos(POWERUP_POOL[i]);
                POWERUP_POOL[i].setVisible(true);
                POWERUP_POOL[i].startTime=System.currentTimeMillis();
                break;
            }
        }
    }
    
    ////////////////////////////////////////////////////////////////////////////
    //--------------------------------- REVISIONS ------------------------------
    // Date       Name                 Tracking #         Description
    // ---------  -------------------  -------------      ----------------------
    // 17JAN2008  James Shen                 	          Initial Creation 
    ////////////////////////////////////////////////////////////////////////////
    /**
     * Operation be done in each tick.
     */
    public void tick(){
        if(type==NOTHING || !isVisible()) return;
        long tickTime = System.currentTimeMillis();
        long refreshPeriod=MILLIS_PER_TICK;
        
        //invulnerable powerup is controlled by the player tank.
        if(type!=INVULNERABLE &&type!=HOME && type!=HOME_DESTROYED){
            if(tickTime-startTime>livePeriod){
                setFrame(NOTHING);
                setVisible(false);
                return;
            }
        }else{
            refreshPeriod=MILLIS_PER_TICK/10;
        }
        if(timeTaken>=refreshPeriod){
            showNextFrame=!showNextFrame;
            if(type==INVULNERABLE){
               if(showNextFrame){
                    setFrame(0);
                }else{
                    setFrame(1);
                } 
            }else if(type==HOME || type==HOME_DESTROYED){
               setFrame(type); 
            }else{
                if(showNextFrame){
                    setFrame(type);
                }else{
                    setFrame(NOTHING);
                }
            }
            timeTaken = System.currentTimeMillis() - tickTime;
        } else{
            timeTaken+=1;
        }
    }
    
    ////////////////////////////////////////////////////////////////////////////
    //--------------------------------- REVISIONS ------------------------------
    // Date       Name                 Tracking #         Description
    // ---------  -------------------  -------------      ----------------------
    // 17JAN2008  James Shen                 	          Initial Creation 
    ////////////////////////////////////////////////////////////////////////////
    /**
     * Check if player's tank move above the powerup.
     * @param tank player's tank.
     */
    public static void checkPlayerTank(PlayerTank tank){
        Powerup powerup;
        for(int i=1;i<POOL_SIZE;i++){
            if(POWERUP_POOL[i].isVisible()){
                powerup=POWERUP_POOL[i];
                if(powerup.collidesWith(tank,false)){
                    tank.upgrade(powerup);
                    if(!(powerup.type==powerup.HOME ||
                            powerup.type==Powerup.HOME_DESTROYED)){
                        powerup.setVisible(false);
                        Score.show(tank.getX(),tank.getY(),Score.SCORE_500);
                        tank.addScore(500);
                    }
                }
                
            }
        }
    }
    
    
    ////////////////////////////////////////////////////////////////////////////
    //--------------------------------- REVISIONS ------------------------------
    // Date       Name                 Tracking #         Description
    // ---------  -------------------  -------------      ----------------------
    // 15JAN2008  James Shen                 	          Initial Creation
    ////////////////////////////////////////////////////////////////////////////
    /**
     * Get the invulnerable powerup. When player collects this powerup. it shows
     * invulnerable animation.
     * @return the invulnerable powerup.
     */
    public static Powerup getInvulnerable(){
        return POWERUP_POOL[0];
    }
    
    ////////////////////////////////////////////////////////////////////////////
    //--------------------------------- REVISIONS ------------------------------
    // Date       Name                 Tracking #         Description
    // ---------  -------------------  -------------      ----------------------
    // 16JAN2008  James Shen                 	          Initial Creation
    ////////////////////////////////////////////////////////////////////////////
    /**
     * Player has collected {@see Powerup.BOMB}. Enemies should explode immediately.
     */
    public static void removeAllPowerups() {
        for (int i = 1; i < POOL_SIZE; ++i) {
            Powerup powerup = POWERUP_POOL[i];
            powerup.setVisible(false);
        }
    }
    
    ////////////////////////////////////////////////////////////////////////////
    //--------------------------------- REVISIONS ------------------------------
    // Date       Name                 Tracking #         Description
    // ---------  -------------------  -------------      ----------------------
    // 15JAN2008  James Shen                 	          Initial Creation
    ////////////////////////////////////////////////////////////////////////////
    /**
     * Set the layerManager for powerups.
     */
    public static void setLayerManager(LayerManager manager) {
        layerManager = manager;
        if (layerManager != null){
            
            for (int i = 0; i < POOL_SIZE; i++)
                layerManager.append(POWERUP_POOL[i]);
        }
    }
    
    ////////////////////////////////////////////////////////////////////////////
    //--------------------------------- REVISIONS ------------------------------
    // Date       Name                 Tracking #         Description
    // ---------  -------------------  -------------      ----------------------
    // 15JAN2008  James Shen                 	          Initial Creation
    ////////////////////////////////////////////////////////////////////////////
    /**
     * Set the Battle field for powerups.
     */
    public static void setBattleField(BattleField field) {
        battleField = field;
    }

}