canvas实现冠状病毒射击游戏
Posted JackieDYH
tags:
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在线演示
结构
<canvas id='canvas' width='1280' height='720'></canvas>样式
body {
background:#111;
margin:0;
padding:0
}
canvas {
background:#000;
display:block;
cursor:none
}
方法
"use strict"
var stage = {
w:1280,
h:720
}
var _pexcanvas = document.getElementById("canvas");
_pexcanvas.width = stage.w;
_pexcanvas.height = stage.h;
var ctx = _pexcanvas.getContext("2d");
var pointer = {
x:stage.w/2,
y:stage.h/4
}
var scale = 1;
var portrait = true;
var loffset = 0;
var toffset = 0;
var mxpos = 0;
var mypos = 0;
// ------------------------------------------------------------------------------- Gamy
var againprog = 0;
var healthprog = 0;
function newGame() {
score = 0;
health = 100;
enemies=[];
enemies.push(new Enemy());
enemies.push(new Enemy());
enemies.push(new Enemy());
againprog = 0;
}
function drawHeart(x,y,w) {
ctx.beginPath();
ctx.arc(x-w/4, y, w/4, 0.75*Math.PI,0);
ctx.arc(x+w/4, y, w/4, 1*Math.PI, 2.25*Math.PI);
ctx.lineTo(x,y+w/1.5);
ctx.closePath();
ctx.fill();
}
var Cannon = function(x,y,tx,ty) {
this.x = x;
this.y = y;
this.tx = tx;
this.ty = ty;
this.r = 10;
}
var cannons = [];
var gameover = false;
cannons.push(new Cannon(stage.w,stage.h,stage.w/2,stage.h/2));
var firetm = 0;
var fireact = true;
var health = 100;
var score = 0;
var arm = {x:stage.w,y:stage.h};
var arm2 = {x:0,y:stage.h};
var danger = false;
var dangera = 0;
var Enemy = function() {
this.x = stage.w/2;
this.y = stage.h/2;
this.r = 10;
this.tx = Math.floor(Math.random()*stage.w);
this.ty = Math.floor(Math.random()*stage.h);
this.des = false;
this.eyeX = 0.4;
this.eyeY = 0.25;
this.eyeR = 0.25;
this.sp = 50;
this.spl = 1.4;
this.op=1;
this.danger = false;
this.nuked = false;
}
var enemies = [];
// for (var i = 0; i < 10; i++) {
// enemies[i] = new Enemy();
// }
enemies.push(new Enemy());
enemies.push(new Enemy());
enemies.push(new Enemy());
var entm = 0;
var ga =0;
var steptime = 0;
var Star = function() {
this.a = Math.random()*Math.PI*2;
this.v = 3+Math.random()*5;
this.x = stage.w/2;
this.y = stage.h/2;
this.r = 0.2;
}
var Power = function() {
this.type = Math.floor(Math.random()*2)+1;
this.a = Math.random()*Math.PI*2;
this.v = 3+Math.random()*5;
this.x = stage.w/2;
this.y = stage.h/2;
this.r = 0.2;
this.dis = false;
this.op = 1;
}
var powers = [];
var powertm = 0;
var powermax = Math.random()*800+300;
// powermax = 10;
var stars = [];
for (var i =0;i<200;i++) {
stars[i] = new Star();
var st = stars[i];
var move = Math.random()*400;
st.x += Math.sin(st.a)*move;
st.y += Math.cos(st.a)*move;
}
// powers.push(new Power());
function enginestep() {
steptime = Date.now();
ctx.clearRect(0,0,stage.w,stage.h);
ctx.fillStyle = "#ffffff";
for (var i = 0; i < stars.length; i++) {
var st = stars[i];
st.x += Math.sin(st.a)*st.v;
st.y += Math.cos(st.a)*st.v;
st.r += st.v/200;
ctx.beginPath();
ctx.arc(st.x,st.y, st.r, 2*Math.PI, 0);
ctx.fill();
if (st.x>stage.w||st.x<0||st.y<0||st.y>stage.h) {
stars[i] = new Star();
}
}
if (!gameover) {
danger = false;
powertm++;
if (powertm>powermax) {
powers.push(new Power());
powertm = 0;
powermax = Math.random()*1200+600;
// powermax = 10;
}
for (var i = 0; i < powers.length; i++) {
var st = powers[i];
if (!st.des) {
st.x += Math.sin(st.a)*st.v/1.5;
st.y += Math.cos(st.a)*st.v/1.5;
st.r += st.v/15;
} else {
st.r *=1.1;
if (st.type==1) {
st.op += (0-st.op)/10;
} else {
st.op += (0-st.op)/20;
}
st.x += (stage.w/2-st.x)/10;
st.y += (stage.h/2-st.y)/10;
}
if (st.type ==1) {
ctx.fillStyle = "rgba(255,0,0,"+st.op+")";
drawHeart(st.x,st.y-st.r/4, st.r*2);
} else {
ctx.fillStyle = "rgba(255,255,0,"+st.op+")";
ctx.strokeStyle = "rgba(255,255,0,"+st.op+")";
ctx.lineWidth = st.r/10;
ctx.beginPath();
ctx.arc(st.x,st.y, st.r, 2*Math.PI, 0);
ctx.stroke();
ctx.beginPath();
ctx.arc(st.x,st.y, st.r*0.15, 2*Math.PI, 0);
ctx.fill();
ctx.beginPath();
ctx.arc(st.x,st.y, st.r*0.85, 1.67*Math.PI, 2*Math.PI);
ctx.arc(st.x,st.y, st.r*0.25, 2*Math.PI, 1.67*Math.PI,true);
ctx.closePath();
ctx.fill();
ctx.beginPath();
ctx.arc(st.x,st.y, st.r*0.85, 3*Math.PI, 3.33*Math.PI);
ctx.arc(st.x,st.y, st.r*0.25, 3.33*Math.PI,3*Math.PI, true);
ctx.closePath();
ctx.fill();
ctx.beginPath();
ctx.arc(st.x,st.y, st.r*0.85, 2.33*Math.PI, 2.67*Math.PI);
ctx.arc(st.x,st.y, st.r*0.25, 2.67*Math.PI,2.33*Math.PI, true);
ctx.lineTo(st.x,st.y);
ctx.closePath();
ctx.fill();
}
if (st.x>stage.w||st.x<0||st.y<0||st.y>stage.h||st.r>stage.w/2) {
powers.splice(i,1);
if (st.type == 2&&st.r>stage.w/2) {
for (var e = 0; e < enemies.length; e++) {
enemies[e].des = true;
enemies[e].nuked = true;
}
}
i--;
}
}
entm++;
if (enemies.length<10&&entm>300) {
entm=0;
enemies.push(new Enemy());
}
ctx.lineWidth = 2;
for (var i = 0; i < enemies.length; i++) {
var en = enemies[i];
if (!en.danger) {
ctx.strokeStyle = "rgba(0,255,255,"+en.op*2+")";
} else {
health -= 0.01;
ctx.strokeStyle = "rgba(255,0,0,"+en.op*2+")";
danger = true;
}
if (!en.des) {
if (en.danger) {
var randx = Math.floor(Math.random()*4)-2;
var randy = Math.floor(Math.random()*4)-2;
en.x = en.tx+randx;
en.y = en.ty+randy;
} else {
en.x += (en.tx-en.x)/100;
en.y += (en.ty-en.y)/100;
var randx = 0;
var randy = 0;
}
en.r += (50-en.r)/100;
if (Math.abs(50-en.r)<2&&!en.danger) {
en.tx=en.x;
en.ty=en.y;
en.danger=true;
}
ctx.beginPath();
ctx.arc(en.x-en.r*en.eyeX,en.y-en.r*en.eyeY, en.r*en.eyeR, 0, 2*Math.PI);
ctx.stroke();
ctx.beginPath();
ctx.arc(en.x+en.r*en.eyeX,en.y-en.r*en.eyeY, en.r*en.eyeR, 0, 2*Math.PI);
ctx.stroke();
ctx.beginPath();
ctx.arc(en.x,en.y+en.r/4, en.r/3, 2*Math.PI, Math.PI);
ctx.stroke();
ctx.beginPath();
ctx.arc(en.x,en.y, en.r, 0, 2*Math.PI);
ctx.stroke();
} else {
en.eyeR += (0.5-en.eyeR)/5;
en.op += (0-en.op)/5;
// en.sp += (5-en.sp)/20;
en.r += (100-en.r)/20;
en.spl += (2.5-en.spl)/5;
ctx.beginPath();
ctx.arc(en.x-en.r*en.eyeX,en.y-en.r*en.eyeY, en.r*en.eyeR, 0, 2*Math.PI);
ctx.stroke();
ctx.beginPath();
ctx.arc(en.x+en.r*en.eyeX,en.y-en.r*en.eyeY, en.r*en.eyeR, 0, 2*Math.PI);
ctx.stroke();
ctx.beginPath();
ctx.arc(en.x,en.y+en.r/2, en.r*en.eyeR, Math.PI,2*Math.PI);
ctx.stroke();
ctx.beginPath();
ctx.arc(en.x,en.y, en.r, 0, 2*Math.PI);
ctx.stroke();
}
//spikes
for (var s = 0; s < 12; s++) {
var a = (Math.PI*2/12)*s+ga;
ctx.beginPath();
ctx.moveTo(en.x+Math.sin(a)*en.r,en.y+Math.cos(a)*en.r);
ctx.lineTo(en.x+Math.sin(a)*en.r*1.2,en.y+Math.cos(a)*en.r*1.2);
ctx.lineTo(en.x+Math.sin(a+Math.PI/en.sp)*en.r*en.spl,en.y+Math.cos(a+Math.PI/en.sp)*en.r*en.spl);
ctx.lineTo(en.x+Math.sin(a-Math.PI/en.sp)*en.r*en.spl,en.y+Math.cos(a-Math.PI/en.sp)*en.r*en.spl);
ctx.lineTo(en.x+Math.sin(a)*en.r*1.2,en.y+Math.cos(a)*en.r*1.2);
ctx.stroke();
// ctx.fill();
}
if (Math.abs(0.5-en.eyeR)<0.01) {
var rand = Math.floor(Math.random()*2);
if (enemies[i].nuked&&rand==1) {
enemies.splice(i,1);
} else {
enemies[i] = new Enemy();
}
}
}
if (danger) {
dangera += 0.05+(100-health)/1000;
if (dangera>=Math.PI) {
dangera=0;
}
ctx.fillStyle='rgba(255,0,0,'+(1-Math.sin(dangera))/4+')';
ctx.fillRect(0,0,stage.w,stage.h);
if (health<10) {
ctx.fillStyle='rgba(255,255,0,'+(Math.sin(dangera))+')';
ctx.strokeStyle='rgba(255,255,0,'+(Math.sin(dangera))+')';
ctx.lineWidth = 10;
ctx.beginPath();
ctx.lineJoin = 'round';
ctx.moveTo(stage.w/2,stage.h/4);
ctx.lineTo(stage.w/2+stage.h/7,stage.h/2);
ctx.lineTo(stage.w/2-stage.h/7,stage.h/2);
ctx.closePath();
ctx.stroke();
ctx.font = "bold 130px arial";
ctx.textAlign = "center";
ctx.textBaseline = "middle";
ctx.fillText("!",stage.w/2,stage.h/2.5);
ctx.font = "bold 50px arial";
ctx.fillText("LOW HEALTH",stage.w/2,stage.h*0.6);
}
} else {
dangera = 0;
}
healthprog += (health-healthprog)/5;
ctx.fillStyle='#00ffff';
ctx.font = "30px arial";
ctx.textAlign = "left";
ctx.textBaseline = "middle";
ctx.fillText("Health: ",20,40);
ctx.fillText("Score: "+score,stage.w-200,40);
// ctx.fillText("Step: "+(Date.now()-steptime),20,120);
if (health>30) {
ctx.fillStyle='rgba(0,255,255,0.8)';
} else {
ctx.fillStyle='rgba(255,0,0,0.8)';
}
ctx.lineWidth = 2;
ctx.fillRect(130,25,healthprog*3,30);
ctx.strokeStyle = "#00ffff";
ctx.strokeRect(130,25,300,30);
if (health<0) {
gameover = true;
}
} else {
ctx.fillStyle='rgba(0,255,255,0.3)';
ctx.fillRect((stage.w-220)/2,stage.h*0.65-25,againprog,50);
ctx.fillStyle='#00ffff';
ctx.font = "bold 130px arial";
ctx.textAlign = "center";
ctx.textBaseline = "middle";
ctx.fillText("GAME OVER",stage.w/2,stage.h/3);
ctx.font = "bold 50px arial";
ctx.fillText("SCORE: "+score,stage.w/2,stage.h/2);
ctx.font = "bold 30px arial";
ctx.fillText("PLAY AGAIN",stage.w/2,stage.h*0.65);
ctx.strokeRect((stage.w-220)/2,stage.h*0.65-25,220,50);
againprog += (0-againprog)/50;
}
ctx.strokeStyle = "#00ffff";
ctx.fillStyle = "#00ffff";
ctx.lineWidth = 2;
if (fireact) {
firetm++;
if(firetm>5) {
cannons.push(new Cannon(pointer.x+(stage.w-pointer.x)/2.5,pointer.y+(stage.h-pointer.y)/2.5,pointer.x,pointer.y));
cannons.push(new Cannon(pointer.x-(pointer.x)/2.5,pointer.y+(stage.h-pointer.y)/2.5,pointer.x,pointer.y));
firetm=0;
}
arm.x=Math.floor(Math.random()*50)-25+stage.w;
arm.y=Math.floor(Math.random()*50)-25+stage.h;
arm2.x=Math.floor(Math.random()*30)-15;
arm2.y=Math.floor(Math.random()*30)-15+stage.h;
} else {
arm.x=stage.w;
arm.y=stage.h;
arm2.x=0;
arm2.y=stage.h;
}
for (var i = 0; i < cannons.length; i++) {
var can = cannons[i];
can.x += (can.tx-can.x)/5;
can.y += (can.ty-can.y)/5;
can.r += (0-can.r)/5;
ctx.beginPath();
ctx.arc(can.x,can.y, can.r, 0, 2*Math.PI);
ctx.fill();
if (can.r<2&&!gameover) {
for (var a = 0; a < enemies.length; a++) {
var en = enemies[a];
var dx = can.x-en.x;
var dy = can.y-en.y;
var dis = dx*dx+dy*dy;
if (dis<en.r*en.r) {
// enemies.splice(a,1);
if (!enemies[a].des) {
enemies[a].des = true;
score+=10;
}
}
}
}
if (can.r<1&&!gameover) {
for (var a = 0; a < powers.length; a++) {
var en = powers[a];
var dx = can.x-en.x;
var dy = can.y-en.y;
var dis = dx*dx+dy*dy;
if (dis<en.r*en.r) {
if (!en.des) {
powers[a].des = true;
if (en.type==1) {
health = 100;
}
}
}
}
}
if (can.r<1&&gameover) {
if (can.x>(stage.w-220)/2&&can.y>stage.h*0.65-25&&can.x<(stage.w-220)/2+220&&can.y<stage.h*0.65-25+50) {
againprog +=1;
if (againprog>220) {
newGame();
gameover = false;
}
}
}
if (Math.abs(can.tx-can.x)<1) {
cannons.splice(i,1);
}
}
ctx.beginPath();
ctx.moveTo(pointer.x-20,pointer.y);
ctx.lineTo(pointer.x+20,pointer.y);
ctx.stroke();
ctx.beginPath();
ctx.moveTo(pointer.x,pointer.y-20);
ctx.lineTo(pointer.x,pointer.y+20);
ctx.stroke();
ctx.beginPath();
ctx.arc(pointer.x,pointer.y, 8, 0, 2*Math.PI);
ctx.stroke();
ctx.beginPath();
ctx.moveTo(pointer.x+(arm.x-pointer.x)/3,pointer.y+(arm.y-pointer.y)/3+10);
ctx.lineTo(pointer.x+(arm.x-pointer.x)/2.5,pointer.y+(arm.y-pointer.y)/2.5+10);
ctx.lineTo(pointer.x+(arm.x-pointer.x)/2,pointer.y+(arm.y-pointer.y)/2+10);
ctx.lineTo(pointer.x+(arm.x-pointer.x)/1.5,pointer.y+(arm.y-pointer.y)/1.5+50);
ctx.lineTo(pointer.x+(arm.x-pointer.x)/1.2,pointer.y+(arm.y-pointer.y)/1.2+80);
ctx.lineTo(pointer.x+(arm.x-pointer.x)/1.1,pointer.y+(arm.y-pointer.y)/1.1+100);
ctx.stroke();
ctx.beginPath();
ctx.moveTo(pointer.x+(arm.x-pointer.x)/3-10,pointer.y+(arm.y-pointer.y)/3);
ctx.lineTo(pointer.x+(arm.x-pointer.x)/2.5-10,pointer.y+(arm.y-pointer.y)/2.5);
ctx.lineTo(pointer.x+(arm.x-pointer.x)/2-10,pointer.y+(arm.y-pointer.y)/2);
ctx.lineTo(pointer.x+(arm.x-pointer.x)/1.5-50,pointer.y+(arm.y-pointer.y)/1.5);
ctx.lineTo(pointer.x+(arm.x-pointer.x)/1.2-80,pointer.y+(arm.y-pointer.y)/1.2);
ctx.lineTo(pointer.x+(arm.x-pointer.x)/1.1-100,pointer.y+(arm.y-pointer.y)/1.1);
ctx.stroke();
ctx.beginPath();
ctx.moveTo(pointer.x+(arm.x-pointer.x)/3,pointer.y+(arm.y-pointer.y)/3-10);
ctx.lineTo(pointer.x+(arm.x-pointer.x)/2.5,pointer.y+(arm.y-pointer.y)/2.5-10);
ctx.lineTo(pointer.x+(arm.x-pointer.x)/2,pointer.y+(arm.y-pointer.y)/2-10);
ctx.lineTo(pointer.x+(arm.x-pointer.x)/1.5,pointer.y+(arm.y-pointer.y)/1.5-50);
ctx.lineTo(pointer.x+(arm.x-pointer.x)/1.2,pointer.y+(arm.y-pointer.y)/1.2-80);
ctx.lineTo(pointer.x+(arm.x-pointer.x)/1.1,pointer.y+(arm.y-pointer.y)/1.1-100);
ctx.stroke();
ctx.beginPath();
ctx.moveTo(arm2.x+pointer.x-(pointer.x)/3,pointer.y+(arm2.y-pointer.y)/3+10);
ctx.lineTo(arm2.x+pointer.x-(pointer.x)/2.5,pointer.y+(arm2.y-pointer.y)/2.5+10);
ctx.lineTo(arm2.x+pointer.x-(pointer.x)/2,pointer.y+(arm2.y-pointer.y)/2+10);
ctx.lineTo(arm2.x+pointer.x-(pointer.x)/1.5,pointer.y+(arm2.y-pointer.y)/1.5+50);
ctx.lineTo(arm2.x+pointer.x-(pointer.x)/1.2,pointer.y+(arm2.y-pointer.y)/1.2+80);
ctx.lineTo(arm2.x+pointer.x-(pointer.x)/1.1,pointer.y+(arm2.y-pointer.y)/1.1+100);
ctx.stroke();
ctx.beginPath();
ctx.moveTo(arm2.x+pointer.x-(pointer.x)/3-10,pointer.y+(arm2.y-pointer.y)/3);
ctx.lineTo(arm2.x+pointer.x-(pointer.x)/2.5-10,pointer.y+(arm2.y-pointer.y)/2.5);
ctx.lineTo(arm2.x+pointer.x-(pointer.x)/2-10,pointer.y+(arm2.y-pointer.y)/2);
ctx.lineTo(arm2.x+pointer.x-(pointer.x)/1.5-50,pointer.y+(arm2.y-pointer.y)/1.5);
ctx.lineTo(arm2.x+pointer.x-(pointer.x)/1.2-80,pointer.y+(arm2.y-pointer.y)/1.2);
ctx.lineTo(arm2.x+pointer.x-(pointer.x)/1.1-100,pointer.y+(arm2.y-pointer.y)/1.1);
ctx.stroke();
ctx.beginPath();
ctx.moveTo(arm2.x+pointer.x-(pointer.x)/3,pointer.y+(arm2.y-pointer.y)/3-10);
ctx.lineTo(arm2.x+pointer.x-(pointer.x)/2.5,pointer.y+(arm2.y-pointer.y)/2.5-10);
ctx.lineTo(arm2.x+pointer.x-(pointer.x)/2,pointer.y+(arm2.y-pointer.y)/2-10);
ctx.lineTo(arm2.x+pointer.x-(pointer.x)/1.5,pointer.y+(arm2.y-pointer.y)/1.5-50);
ctx.lineTo(arm2.x+pointer.x-(pointer.x)/1.2,pointer.y+(arm2.y-pointer.y)/1.2-80);
ctx.lineTo(arm2.x+pointer.x-(pointer.x)/1.1,pointer.y+(arm2.y-pointer.y)/1.1-100);
ctx.stroke();
ctx.beginPath();
ctx.arc(pointer.x+(arm.x-pointer.x)/3,pointer.y+(arm.y-pointer.y)/3, 10, 0, 2*Math.PI);
ctx.arc(pointer.x+(arm.x-pointer.x)/2.5,pointer.y+(arm.y-pointer.y)/2.5, 10, 0, 2*Math.PI);
ctx.arc(pointer.x+(arm.x-pointer.x)/2,pointer.y+(arm.y-pointer.y)/2, 10, 0, 2*Math.PI);
ctx.arc(pointer.x+(arm.x-pointer.x)/1.5,pointer.y+(arm.y-pointer.y)/1.5, 50, 0, 2*Math.PI);
ctx.arc(pointer.x+(arm.x-pointer.x)/1.2,pointer.y+(arm.y-pointer.y)/1.2, 80, 0, 2*Math.PI);
ctx.arc(pointer.x+(arm.x-pointer.x)/1.1,pointer.y+(arm.y-pointer.y)/1.1, 100, 0, 2*Math.PI);
ctx.stroke();
ctx.beginPath();
ctx.arc(arm2.x+pointer.x-(pointer.x/3),pointer.y+(arm2.y-pointer.y)/3, 10, 0, 2*Math.PI);
ctx.arc(arm2.x+pointer.x-(pointer.x/2.5),pointer.y+(arm2.y-pointer.y)/2.5, 10, 0, 2*Math.PI);
ctx.arc(arm2.x+pointer.x-(pointer.x)/2,pointer.y+(arm2.y-pointer.y)/2, 10, 0, 2*Math.PI);
ctx.arc(arm2.x+pointer.x-(pointer.x)/1.5,pointer.y+(arm2.y-pointer.y)/1.5, 50, 0, 2*Math.PI);
ctx.arc(arm2.x+pointer.x-(pointer.x)/1.2,pointer.y+(arm2.y-pointer.y)/1.2, 80, 0, 2*Math.PI);
ctx.arc(arm2.x+pointer.x-(pointer.x)/1.1,pointer.y+(arm2.y-pointer.y)/1.1, 100, 0, 2*Math.PI);
ctx.stroke();
ctx.fillStyle='#004444';
ctx.font = "14px arial";
ctx.textAlign = "center";
ctx.textBaseline = "middle";
ctx.fillText("Coronavirus Shooting Game, Designed & Developed by Faisal Jawed",stage.w/2,stage.h-20);
}
// ------------------------------------------------------------------------------- events
// ------------------------------------------------------------------------------- events
// ------------------------------------------------------------------------------- events
// ------------------------------------------------------------------------------- events
function toggleFullScreen() {
var doc = window.document;
var docEl = doc.documentElement;
var requestFullScreen = docEl.requestFullscreen || docEl.mozRequestFullScreen || docEl.webkitRequestFullScreen || docEl.msRequestFullscreen;
var cancelFullScreen = doc.exitFullscreen || doc.mozCancelFullScreen || doc.webkitExitFullscreen || doc.msExitFullscreen;
if(!doc.fullscreenElement && !doc.mozFullScreenElement && !doc.webkitFullscreenElement && !doc.msFullscreenElement) {
requestFullScreen.call(docEl);
}
else {
cancelFullScreen.call(doc);
}
}
var ox = 0;
var oy = 0;
function mousestart(e) {
mxpos = (e.pageX-loffset)*scale;
mypos = (e.pageY-toffset)*scale;
pointer.x = mxpos;
pointer.y = mypos;
// fireact = true;
}
function mousemove(e) {
mxpos = (e.pageX-loffset)*scale;
mypos = (e.pageY-toffset)*scale;
pointer.x = mxpos;
pointer.y = mypos;
// ball.vY += (mxpos-ox)/15*line.d;
ox = mxpos;
}
function mouseend(e) {
// fireact = false;
}
var moveX = 0;
var moveY = 0;
var moveZ = 0;
function keydowned(e) {
// if (e.keyCode==65) {
// moveX = 10;
// } else if (e.keyCode==68) {
// moveX = -10;
// }
// if (e.keyCode==83) {
// moveY = -10;
// } else if (e.keyCode==87) {
// moveY = 10;
// }
// if (e.keyCode==69) {
// moveZ = 10;
// } else if (e.keyCode==81) {
// moveZ = -10;
// }
// console.log(e.keyCode);
}
function keyuped(e) {
// if (e.keyCode==65) {
// moveX = 0;
// } else if (e.keyCode==68) {
// moveX = 0;
// }
// if (e.keyCode==87) {
// moveY = 0;
// } else if (e.keyCode==83) {
// moveY = 0;
// }
// if (e.keyCode==81) {
// moveZ = 0;
// } else if (e.keyCode==69) {
// moveZ = 0;
// }
// console.log("u"+e.keyCode);
}
window.addEventListener('mousedown', function(e) {
mousestart(e);
}, false);
window.addEventListener('mousemove', function(e) {
mousemove(e);
}, false);
window.addEventListener('mouseup', function(e) {
mouseend(e);
}, false);
window.addEventListener('touchstart', function(e) {
e.preventDefault();
mousestart(e.touches[0]);
}, false);
window.addEventListener('touchmove', function(e) {
e.preventDefault();
mousemove(e.touches[0]);
}, false);
window.addEventListener('touchend', function(e) {
e.preventDefault();
mouseend(e.touches[0]);
}, false);
window.addEventListener('keydown', function(e) {
keydowned(e);
}, false);
window.addEventListener('keyup', function(e) {
keyuped(e);
}, false);
// ------------------------------------------------------------------------ stager
// ------------------------------------------------------------------------ stager
// ------------------------------------------------------------------------ stager
// ------------------------------------------------------------------------ stager
function _pexresize() {
var cw = window.innerWidth;
var ch = window.innerHeight;
if (cw<=ch*stage.w/stage.h) {
portrait = true;
scale = stage.w/cw;
loffset = 0;
toffset = Math.floor(ch-(cw*stage.h/stage.w))/2;
_pexcanvas.style.width = cw + "px";
_pexcanvas.style.height = Math.floor(cw*stage.h/stage.w) + "px";
} else {
scale = stage.h/ch;
portrait = false;
loffset = Math.floor(cw-(ch*stage.w/stage.h))/2;
toffset = 0;
_pexcanvas.style.height = ch + "px";
_pexcanvas.style.width = Math.floor(ch*stage.w/stage.h) + "px";
}
_pexcanvas.style.marginLeft = loffset +"px";
_pexcanvas.style.marginTop = toffset +"px";
}
window.requestAnimFrame = (function(){
return window.requestAnimationFrame ||
window.webkitRequestAnimationFrame ||
window.mozRequestAnimationFrame ||
window.oRequestAnimationFrame ||
window.msRequestAnimationFrame ||
function( callback ){
window.setTimeout(callback, 1000 / 60);
};})();
var fps = 60;
var nfcount = 0;
function animated() {
requestAnimFrame(animated);
enginestep();
nfcount++;
ctx.fillStyle='#00ffff';
ctx.font = "12px arial";
ctx.textAlign = "left";
ctx.fillText("FPS: "+Math.floor(fps),10,stage.h-20);
}
_pexresize();
animated();
function countfps() {
fps = nfcount;
nfcount = 0;
}
setInterval(countfps,1000);以上是关于canvas实现冠状病毒射击游戏的主要内容，如果未能解决你的问题，请参考以下文章