package?com.hsj.bird;

import?java.awt.Graphics;
import?java.awt.Graphics2D;
import?java.awt.image.BufferedImage;

import?javax.imageio.ImageIO;

public?class?Bird?{
	/**?鳥飛行位置?這個位置是鳥的中心位置?*/
	int?x;	int?y;
	/**?飛行角度?*/
	double?angle;
	/**?動畫幀?*/
	BufferedImage[]?images;
	/**?當前圖片?*/
	BufferedImage?image;
	/**?當前圖片序號?*/
	int?index?=?0;
	/**?重力加速度?*/
	final?double?g;?
	/**?時間間隔秒?*/
	final?double?t;
	/**?初始上拋速度?*/
	final?double?v0;
	/**?當前上拋速度?*/
	double?speed;
	/**?移動距離?*/
	double?s;
	/**?鳥的范圍?鳥的范圍是一個正方形區域?中心點是xy?*/
	int?size?=?40;
	
	public?Bird（）?throws?Exception?{
		this.g?=?4;?//重力加速度
		this.t?=?0.25;?//每次計算的間隔時間
		this.v0?=?20;?//初始上拋速度
		x?=?132;?//鳥的初始位置
		y?=?275;?//鳥的初始位置
		//加載動畫幀
		images?=?new?BufferedImage[8];
		for（int?i=0;?i<8;?i++）{
			images[i]?=?ImageIO.read（getClass（）.getResource（i+“.png“））;
		}
		image?=?images[0];
	}
	
	/**?飛行一步??
	?*?豎直上拋位移計算
	?*??（1）?上拋速度計算?V=Vo-gt??
		（2）?上拋距離計算?S=Vot-1/2gt^2
	?*?*/
	public?void?step（）{
		//V0?是本次
		double?v0?=?speed;
		//計算垂直上拋運動?經過時間t以后的速度?
		double?v?=?v0?-?g*t;
		//作為下次計算的初始速度
		speed?=?v;
		//計算垂直上拋運動的運行距離
		s?=?v0*t?-?0.5?*?g?*?t?*?t;
		//將計算的距離?換算為?y坐標的變化
		y?=?y?-?（int）s;
		//計算小鳥的仰角?
		angle?=?-Math.atan（s/8）;
		
	}
	public?void?fly（）{
		//更換小鳥的動畫幀圖片?其中/4?是為了調整動畫更新的頻率
		index++;
		image?=?images[（index/8）%images.length];
	}
	/**?小鳥向上飛揚?*/
	public?void?flappy（）{
		//每次小鳥上拋跳躍?就是將小鳥在當前點重新以初始速度?V0?向上拋
		speed?=?v0;
	}
	//繪制時并發執行的?要同步避免?旋轉坐標系對其他繪制方法的影響
	public?synchronized?void?paint（Graphics?g）{
		//g.drawRect（x-size/2?y-size/2?size?size）;
		Graphics2D?g2?=?（Graphics2D）g;
		//旋轉繪圖坐標系?繪制
		g2.rotate（angle?this.x?this.y）;
		//以xy?為中心繪制圖片
		int?x?=?this.x-image.getWidth（）/2;
		int?y?=?this.y-image.getHeight（）/2;
		g.drawImage（image?x?y?null）;
		//旋轉回來?
		g2.rotate（-angle?this.x?this.y）;
	}

	@Override
	public?String?toString（）?{
		return?“Bird?[x=“?+?x?+?“?y=“?+?y?+?“?g=“?+?g?+?“?t=“?+?t?+?“?v0=“
				+?v0?+?“?speed=“?+?speed?+?“s=“+s+“]“;
	}
	/**?判斷鳥是否通過柱子?*/
	public?boolean?pass（Column?col1?Column?col2）?{
		return?col1.x==x?||?col2.x==x;
	}
	/**?判斷鳥是否與柱子和地發生碰撞?*/
	public?boolean?hit（Column?column1?Column?column2?Ground?ground）?{
		//碰到地面
		if（y-size/2?>=?ground.y）{
			return?true;
		}
		//碰到柱子
		return?hit（column1）?||?hit（column2）;
	}
	/**?檢查當前鳥是否碰到柱子?*/
	public?boolean?hit（Column?col）{
		//如果鳥碰到柱子:?鳥的中心點x坐標在?柱子寬度?+?鳥的一半
		if（?x>col.x-col.width/2-size/2?&&?x			if（y>col.y-col.gap/2+size/2?&&?y				return?false;
			}
			return?true;
		}
		return?false;
	}
	
}

?屬性????????????大小?????日期????時間???名稱
-----------?---------??----------?-----??----
?????文件?????????295??2014-02-11?23:29??.classpath
?????文件?????????369??2014-02-11?23:29??.project
?????目錄???????????0??2014-05-08?06:07??.settings\
?????文件?????????587??2014-02-11?23:29??.settings\org.eclipse.jdt.core.prefs
?????目錄???????????0??2014-05-08?06:07??bin\
?????目錄???????????0??2014-05-08?06:07??bin\com\
?????目錄???????????0??2014-05-08?06:07??bin\com\hsj\
?????目錄???????????0??2014-05-08?06:07??bin\com\hsj\bird\
?????文件????????3157??2014-02-18?17:49??bin\com\hsj\bird\0.png
?????文件????????3167??2014-02-18?17:49??bin\com\hsj\bird\1.png
?????文件????????3159??2014-02-18?17:49??bin\com\hsj\bird\2.png
?????文件????????3165??2014-02-18?17:49??bin\com\hsj\bird\3.png
?????文件????????3157??2014-02-18?17:50??bin\com\hsj\bird\4.png
?????文件????????3165??2014-02-18?17:50??bin\com\hsj\bird\5.png
?????文件????????3159??2014-02-18?17:50??bin\com\hsj\bird\6.png
?????文件????????3167??2014-02-18?17:50??bin\com\hsj\bird\7.png
?????文件????????9226??2014-02-18?17:32??bin\com\hsj\bird\bg.png
?????文件????????3494??2014-05-08?06:03??bin\com\hsj\bird\Bird.class
?????文件????????1522??2014-05-08?06:03??bin\com\hsj\bird\Column.class
?????文件????????5588??2014-02-18?12:09??bin\com\hsj\bird\column.png
?????文件????????8684??2014-02-18?12:12??bin\com\hsj\bird\gameover.png
?????文件????????1240??2014-05-08?06:06??bin\com\hsj\bird\Ground.class
?????文件????????3567??2014-02-18?18:14??bin\com\hsj\bird\ground.png
?????文件????????9600??2014-02-18?18:05??bin\com\hsj\bird\start.png
?????文件???????37888??2014-05-08?06:07??bin\com\hsj\bird\Thumbs.db
?????文件?????????827??2014-05-08?06:04??bin\com\hsj\bird\World$1.class
?????文件?????????891??2014-05-08?06:04??bin\com\hsj\bird\World$2.class
?????文件????????3804??2014-05-08?06:04??bin\com\hsj\bird\World.class
?????文件???????46745??2014-02-19?10:07??layout.png
?????文件??????????31??2014-05-08?06:07??run.bat
?????目錄???????????0??2014-05-08?06:07??src\
............此處省略20個文件信息