<html>
<head>
<meta charset="UTF-8">
<title>飞机大战</title>
</head>
<body>
<canvas id="myCanvas" width="320" height="480" style="border: solid">
你的浏览器不支持canvas画布元素，请更新浏览器获得演示
</canvas>
<div id="message_txt" style="display: block;">飞机大战</div>
<div id="score_txt" style="display: block;">分数:0分</div>
<script type="text/javascript">
var canvas = document.getElementById("myCanvas");
var context = canvas.getContext("2d");
document.addEventListener("keydown",onkeydown);
var Plan = function (image,x,y,n) {
this.image = image;
this.x = x;
this.y = y;
this.originX = x;
this.originY = y;
this.width = image.height;
this.isCaught = false;
this.frm = 0;
this.dis = 0;
this.n = n;
};
Plan.prototype.getCaught = function(bool){
this.isCaught = bool;
if (bool == false){
this.orignx = 0;
this.origny = this.y;
}
};
Plan.prototype.testPoint = function(x,y){
var betweenX = (x >= this.x) && (x <= this.x + this.width);
var betweenY = (y >= this.y) && (y <= this.y + this.height);
return betweenX && betweenY;
};
Plan.prototype.move = function(dx,dy){
this.x += dx;
this.y += dy;
};
Plan.prototype.Y = function(){
return this.y;
};
//不断下移飞机
Plan.prototype.draw = function(ctx){
ctx.save();
ctx.translate(this.x,this.y);
ctx.drawImage(this.image,this.frm*this.width,0,this.width,this.height,0,0,this.width,this.height);
ctx.restore();
this.y++;
this.x = this.orignx + 20 * Math.sin(Math.PI / 100*this.y);
this.dis++;
if(this.dis >= 3){//3帧换图
this.dis = 0;
this.frm++;
if(this.frm >= this.n) this.frm = 0;
}
};
//原地不动画飞机
Plan.prototype.draw2 = function(ctx){
ctx.save();
ctx.translate(this.x,this.y);
ctx.drawImage(this.image,this.frm*this.width,0,this.width,this.height,0,0,this.width,this.height);
ctx.restore();
this.dis++;
if(this.dis >= 3){//3帧换图
this.dis = 0;
this.frm++;
if(this.frm >= this.n) this.frm=0;
}
};
//检测飞机碰撞
//将所有子弹对象的矩形区域与敌机对象的矩形区域逐一检测，如果重叠则说明子弹与敌机的碰撞
Plan.prototype.hitTestObject=function(planobj){
if(iscolliding(this.x,this.y,this.width,this.height,
planobj.x,planobj.y,planobj.width,planobj.height))
//发生碰撞
return true;
else
return false;
}
function isColliding(ax,ay,aw,ah,bx,by,bw,bh)
{
if(ay > by + bh || by > ay + ah
|| ax > bx + bw || bx > ax + aw)
return false;
else
return true;
}
//子弹类
var Bullet = function(image,x,y){
this.image=image;
this.x = x;
this.y = y;
this.orignX = x;
this.orignY = y;
this.width = image.width/4;
this.height = image.height;
this.isCaught = false;
this.frm = 0;
this.dis = 0;
}
Bullet.prototype.testPoint = function(x,y){
var betweenX = (x >= this.x) && (x <= this.x + this.width);//////////
var betweenY = (y >= this.y) && (y <= this.y + this.height);
return betweenX && betweenY;
};
Bullet.prototype.move=function(dx,dy){
this.x += dx;
this.y += dy;
};
Bullet.prototype.Y = function(){
return this.y;
};
Bullet.prototype.draw = function(ctx){
ctx.save();
ctx.translate(this.x,this.y);
ctx.drawImage(this.image,this.frm*this.width,0,this.width,this.height,0,0,this.width,this.height);
ctx.restore();
this.y--;
this.dis++;
if(this.dis >= 10){//10帧换图
this.dis = 0;
this.frm++;
if(this.frm >= 4) this.frm = 0;
}
};
Bullet.prototype.hitTestObject = function(planobj){
if(isColliding(this.x,this.y,this.width,this.height,
planobj.x,planobj.y,planobj.width,planobj.height))//发生碰撞
return true;
else
return false;
}
//爆炸动画
var Bomb=function(image,x,y){
this.image = image;
this.x = x;
this.y = y;
this.width = image.width/6;
this.height = image.height;
this.frm = 0;
this.dis = 0;
};
Bomb.prototype.draw2 = function(ctx){
ctx.save();
ctx.translate(this.x,this.y);
if(this.frm >= 6) return ;
ctx.drawImage(this.image,this.frm*this.width,0,this.width,this.height,0,0,this.width,this.height);
ctx.restore();
this.dis++;
if(this.dis >= 10){//10帧换图
this.dis = 0;
this.frm++;
}
};
var plan1,plan2,plan3,plan4,caughtplan = null;
var isClick = false;
var mouseX,mouseY,preX,preY;
var plans=[];
var bullets=[];
var bombs=[];
var score=0;
var overflag=false;//游戏是否结束，true为结束
var myplane;//己方飞机
var image = new Image();
var image2 = new Image();
var image3 = new Image();
var image4 = new Image();
var image5 = new Image();
var bakground = new Image();
bakground.src='map_0.png';
image.src='plan.png';//自己飞机图片
image.onload=function(){
};
image2.src='bomb.png';//爆炸图片
image2.onload=function(){
}
image3.src='enemy.png';//敌机图片
image3.onload=function(){
myplane=new Plan(image,300*Math.random(),400,6);
plan_interval=setInterval(function(){
plans.push(new Plan(image3,300*Math.random(),20*Math.random(),2));
},3000);//3秒产生1架敌机
setInterval(function(){
context.clearRect(0,0,320,480);
context.drawImage(bakground,0,0);
//画自己方飞机
if(!overflag)//游戏没有结束
myplane.draw2(context);//原地不动
//画敌人飞机
for(var i=plans.length - 1; i >= 0; i--){
if (plans[i].Y() > 400)
plans.splice(i,1);//删除敌机
else
plans[i].draw(context);
}
//画子弹
for (var i = bullets.length - 1; i >= 0; i--){
if (bullets[i].Y() < 100)
bullets.splice(i,1);//删除子弹
else
bullets[i].draw(context);
}
//碰撞检测
//判断敌机碰到玩家自己飞机
for (var i = plans.length - 1; i >= 0; i--){
e1 = plans[i];
if(e1!=null && myplane!=null && myplane.hitTestObject(e1))
{
clearInterval(plan_interval);//清除定时器，不再产生敌机
plans.splice(i,1);//删除敌机
bombs.push(new Bomb(image2, myplane.x, myplane.y));
message_txt.innerHTML='敌机碰到玩家自己飞机，游戏结束';
overflag=true;
}
}
//判断子弹碰到敌机
for(var j = bullets.length - 1; j >= 0; j--){
var b1=bullets[j];
for(var i = plans.length - 1;i >= 0; i--){
e1 = plans[i];
if (e1!=null && b1!=null && b1.hitTestObject(e1))//击中敌机
{
plans.splice(i,1);//删除敌机
bullets.splice(i,1);//删除此颗子弹
bombs.push(new Bomb(image2,b1.x,b1.y-36));
message_txt.innerHTML='敌机被击中，加20分';
score+=20;
score_txt.innerHTML='分数：'+score+'分';
}
}
}
//画炸弹
for (var i = bombs.length - 1;i >= 0; i--){
if (bombs[i].frm >= 6)
bombs.splice(i,1);//删除子弹
else
bombs[i].draw2(context);
}
},1000/60);
};
image4.src='bullet.png';//子弹图片
image4.onload=function(){
};
function onKeydown(e){
if(e.keyCode==32){//空格
//发射子弹
bullets.push(new Bullet(image4,myplane.x,myplane.y-36));
}else if(e.keyCode==37){//向左
myplane.move(-10,0);
}else if(e.keyCode==39){//向右
myplane.move(10,0);
}else if(e.keyCode==38){//向上
myplane.move(0,-10);
}else if(e.keyCode==40){//向下
myplane.move(0,10);
}
}
</script>
</body>
</html>```
来源：oschina
链接：https://my.oschina.net/u/4460892/blog/3209467