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Last active October 6, 2015 03:17
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Pacifist Asteroids. Click on the ship and control it with W,A,S,D keys. No bullets, no enemies, no fighting.
Raw
index.html
<!DOCTYPE html>
<html>
<head>
<title>Asteroids</title>
<script src="http://d3js.org/d3.v3.min.js" charset="utf-8"></script>
<script src="asteroids.js" charset="utf-8"></script>
<script type="text/javascript">
Space = function(params /*{width, height}*/) {
this.width = params.width;
this.height = params.height;
this.asteroids = [];
this.vis = d3.select('div')
.append('svg:svg')
.attr('width', this.width)
.attr('height', this.height);
}
Space.prototype.add = function(body) {
var pointStr = "";
for(var i = 0; i < body.x_points.length; i++) {
pointStr+= body.x_points[i]+","+body.y_points[i]+" ";
}
body.set_shape(this.vis.append('svg:polygon').attr('points',pointStr));
}
Space.prototype.add_spaceship = function(spaceship) {
this.spaceship = spaceship;
this.add(spaceship);
}
Space.prototype.add_asteroid = function(asteroid) {
this.asteroids.push(asteroid);
this.add(asteroid);
}
Space.prototype.simulate = function(delta_time) {
var space = this;
var hasCrashed = false;
var refresh = function() {
for(var i in space.asteroids) {
if(space.asteroids[i].collidesWith(space.spaceship) && !hasCrashed ) {
hasCrashed = true;
alert("you crashed");
}
}
bodies = [].concat(space.asteroids);
bodies.push(space.spaceship);
for(var i in bodies) {
var body = bodies[i];
body.integrate(delta_time);
body.redraw();
//clamp
if( body.y > space.height ) {
body.y = 0;
} else if ( body.y < 0 ) {
body.y = space.height;
}
if( body.x > space.width ) {
body.x = 0;
} else if (body.x < 0 ) {
body.x = space.width;
}
}
};
setInterval(refresh, delta_time);
}
Body = function(params /*{x,y,vx,vy,theta,yaw,x_points,y_points}*/) {
this.x = params.x;
this.y = params.y;
this.vx = params.vx;
this.vy = params.vy;
this.theta = params.theta;
this.yaw = params.yaw;
this.x_points = params.x_points;
this.y_points = params.y_points;
}
Body.prototype.set_shape = function(shape) {
this.body = shape;
}
Body.prototype.integrate = function(delta_time) {
this.theta += this.yaw*delta_time;
this.x += this.vx*delta_time;
this.y += this.vy*delta_time;
}
Body.prototype.redraw = function() {
this.body
.data([this])
.attr('transform', function(d) { return "translate("+ d.x +" "+ d.y +") rotate(" + d.theta + " 0 0)";});
}
Body.prototype.getConvexHull = function() {
var x = [];
var y = [];
for(var i in this.x_points) {
x[i] = this.x + this.x_points[i];
y[i] = this.y + this.y_points[i];
}
return {x:x, y:y};
}
Body.prototype.collidesWith = function(otherBody) {
var otherHull = otherBody.getConvexHull();
var thisHull = this.getConvexHull();
var l = thisHull.x.length;
for(var i = 0; i < otherHull.x.length; i++) {
var otherPoint = [otherHull.x[i],otherHull.y[i]];
<!--for(var j = 1; j < l; j++) {-->
<!--var this_point = [thisHull.y[j]-thisHull.y[j-1],-thisHull.x[j]+thisHull.x[j-1]];-->
for(var j = 0; j < l; j++) {
var this_point = [thisHull.y[(j+1)%l]-thisHull.y[j],-thisHull.x[(j+1)%l]+thisHull.x[j]];
var that_point = [otherPoint[0]-thisHull.x[j],otherPoint[1]-thisHull.y[j]];
var dot_prod = this_point[0]*that_point[0] + this_point[1]*that_point[1];
if(dot_prod>0) {
break;
}
}
if(dot_prod<0) {
return true;
}
}
return false;
}
Spaceship = function(params /*{x,y,size}*/) {
Body.call(this,
{space: params.space,
x: params.x,
y: params.y,
vx: 0,
vy: 0,
theta: 0,
yaw: 0,
x_points: [-params.size,-params.size,2*params.size],
y_points: [-params.size,params.size,0]
}
);
//state
var _this = this;
this.thrust = 0; //1 = forward, -1 = backward
this.turn = 0; //1 = right, -1 = left
//params
this.turn_per_milli = .1;
this.thrust_per_milli = .00005;
this.key_delay = 50;
window.onkeydown = function(e) {
var key = e['keyCode'];
switch(key){
case 68://d = yaw left
_this.turn = 1;
break;
case 65://a = yaw right
_this.turn = -1;
break;
case 87://w = forward
_this.thrust = 1;
break;
case 83://s = backward
_this.thrust = -1;
break;
}
};
window.onkeyup = function(e) {
var key = e['keyCode'];
switch(key){
case 65://a = yaw left
_this.turn = 0;
break;
case 68://d = yaw right
_this.turn = 0;
break;
case 87://w = forward
_this.thrust = 0;
break;
case 83://s = backward
_this.thrust = 0;
break;
}
};
}
Spaceship.prototype = Object.create( Body.prototype );
Spaceship.prototype.integrate = function(delta_time) {
var deg2rad = Math.PI/180;
if(this.turn) {
this.theta = this.theta + this.turn*this.turn_per_milli*delta_time;
}
if(this.thrust) {
var del_v = this.thrust*this.thrust_per_milli*delta_time;
var del_vx = del_v*Math.cos(this.theta*deg2rad);
var del_vy = del_v*Math.sin(this.theta*deg2rad);
} else {
var del_vx = 0;
var del_vy = 0;
}
this.vx = this.vx + del_vx;
this.vy = this.vy + del_vy;
Body.prototype.integrate.call(this,delta_time);
}
Asteroid = function(params /*{x,y,vx,vy,size}*/) {
var angles = [0,.7,2,3.5,4,5];
var x_points = []
var y_points = []
for(var a in angles) {
x_points.push(Math.cos(a)*params.size);
y_points.push(Math.sin(a)*params.size);
}
Body.call(this,
{space: params.space,
x: params.x,
y: params.y,
vx: params.vx,
vy: params.vy,
theta: 0,
yaw: .2*(Math.random()-.5),
x_points: x_points,
y_points: y_points
}
)
}
Asteroid.prototype = Object.create( Body.prototype );
Game = function() {
var space = new Space({width:600, height:500});
//TODO the Bodies have to know how big Space is. this shouldn't be necessary.
space.add_spaceship(new Spaceship({x:200,y:200,size:7}));
// space.add_asteroid(new Asteroid({x:100,y:100,vx:0.0,vy:0.0,size:27}));
space.add_asteroid(new Asteroid({ x:Math.random()*601, y:Math.random()*300, vx:Math.random()*.1-.05, vy:Math.random()*.1-.05,size:Math.random()*30+10}));
space.add_asteroid(new Asteroid({ x:Math.random()*601, y:Math.random()*300, vx:Math.random()*.1-.05, vy:Math.random()*.1-.05,size:Math.random()*30+10}));
space.add_asteroid(new Asteroid({ x:Math.random()*601, y:Math.random()*300, vx:Math.random()*.1-.05, vy:Math.random()*.1-.05,size:Math.random()*30+10}));
space.add_asteroid(new Asteroid({ x:Math.random()*601, y:Math.random()*300, vx:Math.random()*.1-.05, vy:Math.random()*.1-.05,size:Math.random()*30+10}));
space.add_asteroid(new Asteroid({ x:Math.random()*601, y:Math.random()*300, vx:Math.random()*.1-.05, vy:Math.random()*.1-.05,size:Math.random()*30+10}));
space.add_asteroid(new Asteroid({ x:Math.random()*601, y:Math.random()*300, vx:Math.random()*.1-.05, vy:Math.random()*.1-.05,size:Math.random()*30+10}));
space.add_asteroid(new Asteroid({ x:Math.random()*601, y:Math.random()*300, vx:Math.random()*.1-.05, vy:Math.random()*.1-.05,size:Math.random()*30+10}));
space.add_asteroid(new Asteroid({ x:Math.random()*601, y:Math.random()*300, vx:Math.random()*.1-.05, vy:Math.random()*.1-.05,size:Math.random()*30+10}));
space.add_asteroid(new Asteroid({ x:Math.random()*601, y:Math.random()*300, vx:Math.random()*.1-.05, vy:Math.random()*.1-.05,size:Math.random()*30+10}));
var delta_time = 60;
space.simulate(delta_time);
}
</script>
</head>
<body>
<!-- This file lives in public/404.html -->
<div class="dialog"></div>
<script type="text/javascript">
var game = new Game();
</script>
</body>
</html>
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