geoginfo.java

赛车程序：先对赛道和赛车建立模型

/**
 * 
 */
package cn.tsinghua.ag5.CarModel;

//import java.math.*;
import cn.tsinghua.ag5.CarModel.*;

/**
 * @author wfq
 *
 */
public class GeogInfo {

	/**
	 * 
	 */
	public GeogInfo() {
		// TODO Auto-generated constructor stub
	}
	
	public static final int s_roadPartNum = 30;
	public static RoadParts s_road[];//= new RoadParts[s_roadPartNum];
	private static double s_maxLeft;
	private static double s_maxRight;
	private static double s_maxTop;
	private static double s_maxBottom;
	private static final double s_margin = 300f;
	public static final double s_curRad = 100;
	
	public static void genRoad()
	{
		s_road = new RoadParts[s_roadPartNum];
		
		s_road[0] = new RoadParts();
		//不可用内部类
		s_road[0].strCur = true;
		s_road[0].length = (100 + 100 * Math.random());
		s_road[0].startX = 0;
		s_road[0].startY = 0;
		s_road[0].endX = Math.round(s_road[0].length);
		s_road[0].endY = 0;
		
		for( int i = 1; i < s_roadPartNum; i++ )
		{
			s_road[i] = new RoadParts();
			
			s_road[i].strCur = Math.random() > 0.3 ? false : true;
			
			if(s_road[i].strCur )
			{
				s_road[i].length = (100 + 100 * Math.random());
				s_road[i].startX = s_road[i-1].endX;
				s_road[i].startY = s_road[i-1].endY;
//				s_road[i].endX = (int)Math.round(s_road[i].startX + s_road[i].length 
//				* Math.cos(2 * Math.PI * Math.random()));
//				s_road[i].endY = (int)Math.round(s_road[i].startY + s_road[i].length 
//				* Math.sin(2 * Math.PI * Math.random()));
				
				if(s_road[i-1].strCur)
				{
					s_road[i].endX = s_road[i].startX + (s_road[i-1].endX - s_road[i-1].startX) * s_road[i].length / s_road[i-1].length;
					s_road[i].endY = s_road[i].startY + (s_road[i-1].endY - s_road[i-1].startY) * s_road[i].length / s_road[i-1].length;
				}else
				{
					double angle = tangentDegree(s_road[i-1].centerX, s_road[i-1].centerY, s_road[i-1].endX, s_road[i-1].endY, s_road[i-1].turn);
					s_road[i].endX = (s_road[i].startX + s_road[i].length * Math.cos(angle));
					s_road[i].endY = (s_road[i].startY + s_road[i].length * Math.sin(angle));
				}
				
			}else
			{
				s_road[i].startX = s_road[i-1].endX;
				s_road[i].startY = s_road[i-1].endY;
				s_road[i].curRadius = (200 - s_curRad + s_curRad * Math.random());
				//can not achieve 180 degree
				s_road[i].angle = (20 + 160 * Math.random());
				s_road[i].turn = Math.random() > 0.5 ? true : false;
				
				double t_arctanyx;	//alfa	上一个路段的切线或直线本身与x轴正方向的夹角
				if(s_road[i-1].strCur)
				{
					t_arctanyx = tangentDegree(s_road[i-1].startX, s_road[i-1].startY, s_road[i-1].endX, s_road[i-1].endY);
				}else
				{
					t_arctanyx= tangentDegree(s_road[i-1].centerX, s_road[i-1].centerY, s_road[i-1].endX, s_road[i-1].endY, s_road[i-1].turn);
				}
				
				if(s_road[i].turn)
				{
					s_road[i].centerX = (s_road[i].startX + s_road[i].curRadius * Math.cos(t_arctanyx + Math.PI/2));
					s_road[i].centerY = (s_road[i].startY + s_road[i].curRadius * Math.sin(t_arctanyx + Math.PI/2));
				}else
				{
					s_road[i].centerX = (s_road[i].startX + s_road[i].curRadius * Math.cos(t_arctanyx - Math.PI/2));
					s_road[i].centerY = (s_road[i].startY + s_road[i].curRadius * Math.sin(t_arctanyx - Math.PI/2));
				}
				
				double t_angleEnd = Math.atan2(s_road[i].startY - s_road[i].centerY, s_road[i].startX-s_road[i].centerX);
				t_angleEnd += s_road[i].turn ? Math.toRadians(s_road[i].angle) : - Math.toRadians(s_road[i].angle);
				s_road[i].endX = (s_road[i].centerX + s_road[i].curRadius * Math.cos(t_angleEnd));
				s_road[i].endY = (s_road[i].centerY + s_road[i].curRadius * Math.sin(t_angleEnd));
				
			}
		}
		
		//计算四维参数
		for(RoadParts i : s_road)
		{
			if(i.startX > s_maxRight)		s_maxRight = i.startX;
			if(i.endX > s_maxRight)		s_maxRight = i.endX;
			if(i.startX < s_maxLeft)		s_maxLeft = i.startX;
			if(i.endX < s_maxLeft)		s_maxLeft = i.endX;

			if(i.startY > s_maxTop)		s_maxTop = i.startY;
			if(i.startY < s_maxBottom)	s_maxBottom = i.startY;	
			if(i.endY > s_maxTop)			s_maxTop = i.endY;
			if(i.endY < s_maxBottom)		s_maxBottom = i.endY;
		}
		
		s_maxRight += s_margin;
		s_maxLeft	-= s_margin;
		s_maxTop += s_margin;
		s_maxBottom -= s_margin;
		
		MyGUI.s_isRoadCreated = true;
	}
	
	/**
	 * 如果是直线返回其本身与x轴正方向的夹角
	 * 如果是曲线，返回其逆时针方向切线与x轴正方向的夹角 -pi -> pi
	 * @return
	 * 输入为两个端点，或是中心和圆上一点
	 */
	public static double tangentDegree( double x0start, double y0start, double xend, double yend)
	{
//		if(p_strCur)
//		{
			return Math.atan2(yend-y0start, xend-x0start);
//		}else
//		{
//			double tmp = Math.atan2(yend - y0start, xend - x0start) + Math.PI / 2;
//			return tmp > Math.PI ? tmp - 2 * Math.PI : tmp;
//		}
	}
	
	public static double tangentDegree( double x0start, double y0start, double xend, double yend, boolean p_turn)
	{
		double tmp = Math.atan2(yend - y0start, xend - x0start) + (p_turn ? Math.PI / 2 : - Math.PI / 2);
		if(tmp > Math.PI)
			tmp -= 2 * Math.PI;
		if(tmp <= - Math.PI)
			tmp += 2 * Math.PI ;
		return tmp;
	}
	

	/**
	 * @return the maxLeft
	 */
	public static double getMaxLeft() {
		return s_maxLeft;
	}

	/**
	 * @return the maxRight
	 */
	public static double getMaxRight() {
		return s_maxRight;
	}

	/**
	 * @return the maxTop
	 */
	public static double getMaxTop() {
		return s_maxTop;
	}

	/**
	 * @return the maxBottom
	 */
	public static double getMaxBottom() {
		return s_maxBottom;
	}

}



class RoadParts  
{
	boolean strCur;		//直道true，弯道false
	double length;		//100-200, 弯道无此属性
	double startX;
	double startY;
	double endX;
	double endY;
	
	double curRadius;	//100-200
	double angle;		//20-180 逆时针	此处为角度，其他都为弧度
	boolean turn;		//左true，右false
	double centerX;
	double centerY;
	
}