enemytank.java

还记得儿时在游戏机上玩坦克大战吗？如今这种经典游戏不在游戏机上玩了

                if(newBornTimer*23-1>=0){
                   setFrame(newBornTimer*23-1);
                }}
                catch(Exception e){
                    System.out.println("Enemythink");
                }
            }
        } else{
            changeDirection(direction);
            if(direction!=BattleField.NONE){
                setTankFrame();
            }
        }
        
    }
    
    ////////////////////////////////////////////////////////////////////////////
    //--------------------------------- REVISIONS ------------------------------
    // Date       Name                 Tracking #         Description
    // ---------  -------------------  -------------      ----------------------
    // 15JAN2008  James Shen                 	          Initial Creation
    ////////////////////////////////////////////////////////////////////////////
    /**
     * Operation be done in each tick.
     */
    public void tick(){
        if(immobilizedStartTime>0){
            long tickTime=System.currentTimeMillis();
            if(tickTime-immobilizedStartTime>immobilizedPeriod){
                immobilizedStartTime=0;
            }
        }else{
            super.tick();
        }
    }
    
    ////////////////////////////////////////////////////////////////////////////
    //--------------------------------- REVISIONS ------------------------------
    // Date       Name                 Tracking #         Description
    // ---------  -------------------  -------------      ----------------------
    // 18JAN2008  James Shen                 	          Initial Creation
    ////////////////////////////////////////////////////////////////////////////
    /**
     * Intialize the player tank after been destoryed or first start.
     */
    public void initTank(){
        status=STATUS_NEW_BORN;
        switch(type){
            case TYPE_SIMPLE:
            case TYPE_SMART:
                speed=ResourceManager.TILE_WIDTH/6;
                blood=1;
                break;
            case TYPE_FAST:
                blood=1;
                speed=ResourceManager.TILE_WIDTH/2;
                break;
            case TYPE_HEAVY:
                speed=ResourceManager.TILE_WIDTH/6;
                blood=4;
                break;
        }
    }
    
    ////////////////////////////////////////////////////////////////////////////
    //--------------------------------- REVISIONS ------------------------------
    // Date       Name                 Tracking #         Description
    // ---------  -------------------  -------------      ----------------------
    // 18JAN2008  James Shen                 	          Initial Creation
    ////////////////////////////////////////////////////////////////////////////
    /**
     * Set if the tank has prize.
     * @param hasPrize true,has prize.
     */
    public void setHasPrize(boolean hasPrize){
        this.hasPrize=hasPrize;
    }
    
    ////////////////////////////////////////////////////////////////////////////
    //--------------------------------- REVISIONS ------------------------------
    // Date       Name                 Tracking #         Description
    // ---------  -------------------  -------------      ----------------------
    // 16JAN2008  James Shen                 	          Initial Creation
    ////////////////////////////////////////////////////////////////////////////
    /**
     * Player has collected {@see Powerup.BOMB}. Enemies should explode immediately.
     */
    public static void explodeAllEmenies() {
        for (int i = 1; i < POOL_SIZE; ++i) {
            Tank tank = TANK_POOL[i];
            if (tank.isVisible()){
                ((EnemyTank)tank).blood=1;
                tank.explode();
            }
        }
        immobilizedStartTime=0;
    }
      
    ////////////////////////////////////////////////////////////////////////////
    //--------------------------------- REVISIONS ------------------------------
    // Date       Name                 Tracking #         Description
    // ---------  -------------------  -------------      ----------------------
    // 16JAN2008  James Shen                 	          Initial Creation
    ////////////////////////////////////////////////////////////////////////////
    /**
     * Get the count of all visible enemy tanks.
     * @return the count of all visible enemy tanks.
     */
    public static int getVisibleEnemyTanks(){
        int count=0;
        for(int i=1;i<POOL_SIZE;i++){
            if(TANK_POOL[i].isVisible()){
                count++;
            }
        }
        return count;
    }
    
    ////////////////////////////////////////////////////////////////////////////
    //--------------------------------- REVISIONS ------------------------------
    // Date       Name                 Tracking #         Description
    // ---------  -------------------  -------------      ----------------------
    // 16JAN2008  James Shen                 	          Initial Creation
    ////////////////////////////////////////////////////////////////////////////
    /**
     * Create a new enemy tank.
     * @param type the type of enemy tank.
     * @return an enemy tank or null.
     */
    public static EnemyTank newEnemyTank(int type){
        EnemyTank enemyTank=getFreeEnemyTank(type);
        if(enemyTank!=null){
            enemyTank.initTank();
            enemyTank.setVisible(true);
        }
        return enemyTank;
    }
    
    ////////////////////////////////////////////////////////////////////////////
    //--------------------------------- REVISIONS ------------------------------
    // Date       Name                 Tracking #         Description
    // ---------  -------------------  -------------      ----------------------
    // 16JAN2008  James Shen                 	          Initial Creation
    ////////////////////////////////////////////////////////////////////////////
    /**
     * Set new tank frame based on type,direction,hasPrize.
     */
    protected void setTankFrame(){
        switchImage=!switchImage;
        int offset=switchImage ? 0: 1;
        int offset1=hasPrize ?2:0;
        int frame=direction*23+offset+offset1+type*4+(blood-1)*2;
        if(type==TYPE_HEAVY && hasPrize){
            frame=direction*23+offset+type*4+8;
        }
        try{
        if(frame>=0 || frame<92){
            setFrame(frame);
        }}
        catch(Exception e){
            //System.out.println("enemy:"+frame+","+blood);
        }
        
    }
    
    ////////////////////////////////////////////////////////////////////////////
    //--------------------------------- REVISIONS ------------------------------
    // Date       Name                 Tracking #         Description
    // ---------  -------------------  -------------      ----------------------
    // 16JAN2008  James Shen                 	          Initial Creation
    ////////////////////////////////////////////////////////////////////////////
    /**
     * Explode a tank.
     */ 
    protected void explode() {
        
        if(type==TYPE_HEAVY && hasPrize && blood==4){
            GameScene.canPutPowerup=true;
            hasPrize=false;
        }
        blood--;
        if(blood==0){
            super.explode();
            Score.show(getX(),getY(),score);
            //this global variable approach is not that good.
            GameScene.enemyTankRemains--;
            if(hasPrize){
                GameScene.canPutPowerup=true;
            }
            GameScene.enemyTanksCount[type]++;
        }
    }
    
    ////////////////////////////////////////////////////////////////////////////
    //--------------------------------- REVISIONS ------------------------------
    // Date       Name                 Tracking #         Description
    // ---------  -------------------  -------------      ----------------------
    // 16JAN2008  James Shen                 	          Initial Creation
    ////////////////////////////////////////////////////////////////////////////
    /**
     * Get a free enemy tank based on given type.
     * @param type the type of enemy tank.
     * @return an enemy tank or null.
     */
    private static EnemyTank getFreeEnemyTank(int type){
        EnemyTank enemyTank=null;
        int left=0,right=0;
        switch(type){
            case TYPE_SIMPLE:
                left=1;right=7;
                break;
            case TYPE_FAST:
                left=8;right=11;
                break;
            case TYPE_SMART:
                left=12;right=15;
                break;
            case TYPE_HEAVY:
                left=16;right=19;
                break;
        }
        for(int i=left;i<=right;i++){
            enemyTank=(EnemyTank)TANK_POOL[i];
            if(!enemyTank.isVisible()){
                battleField.initEnemyTankPos(enemyTank);
                enemyTank.setVisible(true);
                if(overlapsTank(enemyTank)){
                    enemyTank.setVisible(false);
                    enemyTank=null;
                    continue;
                }
                return enemyTank;
            }
        }
        return null;
    }
    
}