panda.java

一个简单的j2me编写的ACT游戏

import javax.microedition.lcdui.Graphics;
import javax.microedition.lcdui.Image;

public class Panda{
	public static final byte CLIPW = 54,CLIPH = 30;
	public static final byte[][] IMGCLIP = {
			{0,0,24,29},
			{24,0,24,29},
			{48,0,24,29},
			{72,0,32,29},
			{0,29,39,30},
			{39,29,30,30},
	};
	
//	横向加速度，横向摩擦系数，横向最高速
	public static final int AX = 2,RUB = 1,MAXSPEEDX = AX*8;
//	跳跃初速度
	public static final byte JUMPV0 = -30;
//	坐标和宽高
	int x,y,width = 12,height = 30;
//	方向
	byte direction;
//	横向速度，纵向速度
	int speedX,speedY;
//	是否已起跳
	boolean isJump;
//	在空中滞留时间，用来计算抛物线
	int cnt_JumpTime;
//	目前所处地平线
	int skyLine;
//	跳台左边界和右边界
	int leftX = -1,rightX = -1;
	int frame;
	int transform;
	static Image img;
	
	public Panda() {
		img = PandaCanvas.img_Panda;
	}
	
//	维护移动数据
	public final void setMove(){
//		如果已起跳，则处理碰撞，计算坐标
		if(isJump){
			cnt_JumpTime ++;
			speedY += PandaCanvas.G;
			if(!isVCollidesWithBarrier()){
				if(y >= PandaCanvas.skyLine-height-speedY){
					y = PandaCanvas.skyLine-height;
					skyLine = y + height;
					leftX = -1;
					rightX = -1;
					isJump = false;
					cnt_JumpTime = 0;
				}else
					y += speedY;
			}
		}
//		不写这一句在一格空缺的障碍物上掉不下来，至于为什么我也没搞清楚，是调试出来的
		isHCollidesWithBarrier();
//		根据横向的方向，处理碰撞，计算坐标
		switch(direction)
		{
		case PandaCanvas.DIR_NONE:
			frame = 0;
			if(speedX >= RUB*AX){
				speedX -= RUB*AX;
				if(isHCollidesWithBarrier())
					break;
			}else if(speedX <= -RUB*AX){
				speedX += RUB*AX;
				if(isHCollidesWithBarrier())
					break;
			}
			break;
		case PandaCanvas.DIR_LEFT:
			frame = PandaCanvas.m_Cnt_Time%3;
			if(speedX > -MAXSPEEDX)
				speedX -= AX;
			transform = PandaCanvas.TRANS_NONE;
			if(isHCollidesWithBarrier())
				break;
			break;
			
		case PandaCanvas.DIR_RIGHT:
			frame = PandaCanvas.m_Cnt_Time%3;
			if(speedX < MAXSPEEDX)
				speedX += AX;
			transform = PandaCanvas.TRANS_HORIZONTAL;
			if(isHCollidesWithBarrier())
				break;
			break;
		}
		if(speedX < 0){
			if(x <= -speedX)
				x = 0;
			else
				x += speedX;
		}else if(speedX > 0){
			if(x >= PandaCanvas.mapW-width-speedX)
				x = PandaCanvas.mapW-width;
			else
				x += speedX;
		}
//		摄象机跟随
		Camera.setFollow(this);
	}
	
//	纵向碰撞处理
	public final boolean isVCollidesWithBarrier(){
		if(speedY != 0){
			if(speedY < 0){
				for(int i=0;i<PandaCanvas.collides.length;i++){
		    		if(x + width < PandaCanvas.collides[i][0] || x > PandaCanvas.collides[i][0]+PandaCanvas.collides[i][2])
						continue;
		    		if(y < PandaCanvas.collides[i][1]+PandaCanvas.collides[i][3])
		    			continue;
		    		if(y + speedY <= PandaCanvas.collides[i][1]+PandaCanvas.collides[i][3]){
		    			y = PandaCanvas.collides[i][1]+PandaCanvas.collides[i][3];
		    			speedY = -speedY/2;
		    			cnt_JumpTime = 0;
		    			return true;
		    		}
		    	}
			}else{
				for(int i=0;i<PandaCanvas.collides.length;i++){
		    		if(x + width < PandaCanvas.collides[i][0] || x > PandaCanvas.collides[i][0]+PandaCanvas.collides[i][2])
						continue;
		    		if(y + height > PandaCanvas.collides[i][1])
		    			continue;
		    		if(y + height + speedY >= PandaCanvas.collides[i][1]){
		    			y = PandaCanvas.collides[i][1] - height;
		    			skyLine = y + height;
						leftX = PandaCanvas.collides[i][0];
						rightX = PandaCanvas.collides[i][0]+PandaCanvas.collides[i][2];
		    			cnt_JumpTime = 0;
		    			speedY = 0;
		    			isJump = false;
		    			return true;
		    		}
		    	}
			}
		}
		return false;
	}
	
//	横向碰撞处理
	public final boolean isHCollidesWithBarrier(){
		if(speedX != 0){
			if(speedX > 0){
				for(int i=0;i<PandaCanvas.collides.length;i++){
		    		if(y + height < PandaCanvas.collides[i][1] || y > PandaCanvas.collides[i][1]+PandaCanvas.collides[i][3])
						continue;
		    		if(x+width > PandaCanvas.collides[i][0])
		    			continue;
		    		if(x+width+speedX >= PandaCanvas.collides[i][0]){
		    			x = PandaCanvas.collides[i][0] - width - 1;
		    			speedX = 0;
		    			if(speedY < 0)
		    				speedY = 0;
		    			return true;
		    		}
		    	}
			}else{
				for(int i=0;i<PandaCanvas.collides.length;i++){
					if(y + height < PandaCanvas.collides[i][1] || y > PandaCanvas.collides[i][1]+PandaCanvas.collides[i][3])
						continue;
		    		if(x < PandaCanvas.collides[i][0]+PandaCanvas.collides[i][2])
		    			continue;
		    		if(x+speedX <= PandaCanvas.collides[i][0]+PandaCanvas.collides[i][2]){
		    			x = PandaCanvas.collides[i][0]+PandaCanvas.collides[i][2] + 1;
		    			speedX = 0;
		    			if(speedY < 0)
		    				speedY = 0;
		    			return true;
		    		}
		    	}
			}
		}
		if(leftX != -1 && rightX != -1 && !isJump){
			if(x+width < leftX || x > rightX){
				isJump = true;
			}
		}
		return false;
	}
	
	public final void paint(Graphics g){
		g.drawRegion(img,IMGCLIP[frame][0],IMGCLIP[frame][1],IMGCLIP[frame][2],IMGCLIP[frame][3],transform,x-5-Camera.x,y-Camera.y,0);
	}
	
	
}