var calculateDistance = function(object1, object2){
x = Math.abs(object1.x - object2.x);
y = Math.abs(object1.y - object2.y);
return Math.sqrt((x * x) + (y * y));
};
var calcMagnitude = function(x, y) {
return Math.sqrt((x * x) + (y * y));
};
var calcVectorAdd = function(v1, v2) {
return {x: v1.x + v2.x, y: v1.y + v2.y};
};
var random = function( min, max ) {
return min + Math.random() * ( max - min );
};
var getRandomItem = function(list, weight) {
var total_weight = weight.reduce(function (prev, cur, i, arr) {
return prev + cur;
});
var random_num = random(0, total_weight);
var weight_sum = 0;
//console.log(random_num)
for (var i = 0; i < list.length; i++) {
weight_sum += weight[i];
weight_sum = +weight_sum.toFixed(2);
if (random_num <= weight_sum) {
return list[i];
}
}
// end of function
};
/***********************
BOID
***********************/
function Boid(x, y) {
this.init(x, y);
}
Boid.prototype = {
init: function(x, y) {
//body
this.type = "boid";
this.alive = true;
this.health = 1;
this.maturity = 4;
this.speed = 6;
this.size = 5;
this.hungerLimit = 12000;
this.hunger = 0;
this.isFull = false;
this.digestTime = 400;
this.color = 'rgb(' + ~~random(0,100) + ',' + ~~random(50,220) + ',' + ~~random(50,220) + ')';
//brains
this.eyesight = 100; //range for object dectection
this.personalSpace = 20; //distance to avoid safe objects
this.flightDistance = 60; //distance to avoid scary objects
this.flockDistance = 100; //factor that determines how attracted the boid is to the center of the flock
this.matchVelFactor = 6; //factor that determines how much the flock velocity affects the boid. less = more matching
this.x = x || 0.0;
this.y = y || 0.0;
this.v = {
x: random(-1, 1),
y: random(-1, 1),
mag: 0
};
this.unitV = {
x: 0,
y: 0,
};
this.v.mag = calcMagnitude(this.v.x, this.v.y);
this.unitV.x = (this.v.x / this.v.mag);
this.unitV.y = (this.v.y / this.v.mag);
},
wallAvoid: function(ctx) {
var wallPad = 10;
if (this.x < wallPad) {
this.v.x = this.speed;
} else if (this.x > ctx.width - wallPad) {
this.v.x = -this.speed;
}
if (this.y < wallPad) {
this.v.y = this.speed;
} else if (this.y > ctx.height - wallPad) {
this.v.y = -this.speed;
}
},
ai: function(boids, index, ctx) {
percievedCenter = {
x: 0,
y: 0,
count: 0
};
percievedVelocity = {
x: 0,
y: 0,
count: 0
};
mousePredator = {
x: ((typeof ctx.touches[0] === "undefined") ? 0 : ctx.touches[0].x),
y: ((typeof ctx.touches[0] === "undefined") ? 0 : ctx.touches[0].y)
};
for (var i = 0; i < boids.length; i++) {
if (i != index) {
dist = calculateDistance(this, boids[i]);
//Find all other boids close to it
if (dist < this.eyesight) {
//if the same species then flock
if (boids[i].type == this.type) {
//Alignment
percievedCenter.x += boids[i].x;
percievedCenter.y += boids[i].y;
percievedCenter.count++;
//Cohesion
percievedVelocity.x += boids[i].v.x;
percievedVelocity.y += boids[i].v.y;
percievedVelocity.count++;
//Separation
if (dist < this.personalSpace + this.size + this.health) {
this.avoidOrAttract("avoid", boids[i]);
}
} else {
//if other species fight or flight
if (dist < this.size + this.health + boids[i].size + boids[i].health) {
this.eat(boids[i]);
} else {
this.handleOther(boids[i]);
}
}
}//if close enough
}//dont check itself
}//Loop through boids
//Get the average for all near boids
if (percievedCenter.count > 0) {
percievedCenter.x = ((percievedCenter.x / percievedCenter.count) - this.x) / this.flockDistance;
percievedCenter.y = ((percievedCenter.y / percievedCenter.count) - this.y) / this.flockDistance;
this.v = calcVectorAdd(this.v, percievedCenter);
}
if (percievedVelocity.count > 0) {
percievedVelocity.x = ((percievedVelocity.x / percievedVelocity.count) - this.v.x) / this.matchVelFactor;
percievedVelocity.y = ((percievedVelocity.y / percievedVelocity.count) - this.v.y) / this.matchVelFactor;
this.v = calcVectorAdd(this.v, percievedVelocity);
}
//Avoid Mouse
if (calculateDistance(mousePredator, this) < this.eyesight) {
var mouseModifier = 20;
this.avoidOrAttract("avoid", mousePredator, mouseModifier);
}
this.wallAvoid(ctx);
this.limitVelocity();
},
setUnitVector: function() {
var magnitude = calcMagnitude(this.v.x, this.v.y);
this.v.x = this.v.x / magnitude;
this.v.y = this.v.y / magnitude;
},
limitVelocity: function() {
this.v.mag = calcMagnitude(this.v.x, this.v.y);
this.unitV.x = (this.v.x / this.v.mag);
this.unitV.y = (this.v.y / this.v.mag);
if (this.v.mag > this.speed) {
this.v.x = this.unitV.x * this.speed;
this.v.y = this.unitV.y * this.speed;
}
},
avoidOrAttract: function(action, other, modifier) {
var newVector = {x: 0, y: 0};
var direction = ((action === "avoid") ? -1 : 1);
var vModifier = modifier || 1;
newVector.x += ( (other.x - this.x) * vModifier ) * direction;
newVector.y += ( (other.y - this.y) * vModifier ) * direction;
this.v = calcVectorAdd(this.v, newVector);
},
move: function() {
this.x += this.v.x;
this.y += this.v.y;
if (this.v.mag > this.speed) {
this.hunger += this.speed;
} else {
this.hunger += this.v.mag;
}
},
eat: function(other) {
if (!this.isFull) {
if (other.type === "plant") {
other.health--;
this.health++;
this.isFull = true;
this.hunger = 0;
}
}
},
handleOther: function(other) {
if (other.type === "predator") {
this.avoidOrAttract("avoid", other);
}
},
metabolism: function() {
if (this.hunger >= this.hungerLimit) {
this.health--;
this.hunger = 0;
}
if (this.hunger >= this.digestTime) {
this.isFull = false;
}
if (this.health <= 0) {
this.alive = false;
}
},
mitosis: function(boids) {
if (this.health >= this.maturity) {
//reset old boid
this.health = 1;
birthedBoid = new Boid(
this.x + random(-this.personalSpace, this.personalSpace),
this.y + random(-this.personalSpace, this.personalSpace)
);
birthedBoid.color = this.color;
boids.push(birthedBoid);
}
},
draw: function( ctx ) {
drawSize = this.size + this.health;
ctx.beginPath();
ctx.moveTo( this.x + ( this.unitV.x * drawSize ), this.y + ( this.unitV.y * drawSize ));
ctx.lineTo( this.x + ( this.unitV.y * drawSize ), this.y - ( this.unitV.x * drawSize ));
ctx.lineTo( this.x - ( this.unitV.x * drawSize * 2 ), this.y - ( this.unitV.y * drawSize * 2 ));
ctx.lineTo( this.x - ( this.unitV.y * drawSize ), this.y + ( this.unitV.x * drawSize ));
ctx.lineTo( this.x + ( this.unitV.x * drawSize ), this.y + ( this.unitV.y * drawSize ));
ctx.fillStyle = this.color;
ctx.shadowBlur = 20;
ctx.shadowColor = this.color;
ctx.fill();
}
};
Predator.prototype = new Boid();
Predator.prototype.constructor = Predator;
Predator.constructor = Boid.prototype.constructor;
function Predator(x, y) {
this.init(x, y);
this.type = "predator";
//body
this.maturity = 6;
this.speed = 6;
this.hungerLimit = 25000;
this.color = 'rgb(' + ~~random(100,250) + ',' + ~~random(10,30) + ',' + ~~random(10,30) + ')';
//brains
this.eyesight = 150;
this.flockDistance = 300;
}
Predator.prototype.eat = function(other) {
if (!this.isFull) {
if (other.type === "boid") {
other.health--;
this.health++;
this.isFull = true;
this.hunger = 0;
}
}
};
Predator.prototype.handleOther = function(other) {
if (other.type === "boid") {
if (!this.isFull) {
this.avoidOrAttract("attract", other);
}
}
};
Predator.prototype.mitosis = function(boids) {
if (this.health >= this.maturity) {
//reset old boid
this.health = 1;
birthedBoid = new Predator(
this.x + random(-this.personalSpace, this.personalSpace),
this.y + random(-this.personalSpace, this.personalSpace)
);
birthedBoid.color = this.color;
boids.push(birthedBoid);
}
};
Plant.prototype = new Boid();
Plant.prototype.constructor = Plant;
Plant.constructor = Boid.prototype.constructor;
function Plant(x, y) {
this.init(x, y);
this.type = "plant";
//body
this.speed = 0;
this.size = 10;
this.health = ~~random(1, 10);
this.color = 'rgb(' + ~~random(130,210) + ',' + ~~random(40,140) + ',' + ~~random(160,220) + ')';
//brains
this.eyesight = 0;
this.flockDistance = 0;
this.eyesight = 0; //range for object dectection
this.personalSpace = 100; //distance to avoid safe objects
this.flightDistance = 0; //distance to avoid scary objects
this.flockDistance = 0; //factor that determines how attracted the boid is to the center of the flock
this.matchVelFactor = 0; //factor that determines how much the flock velocity affects the boid
}
Plant.prototype.ai = function(boids, index, ctx) { };
Plant.prototype.move = function() { };
Plant.prototype.mitosis = function(boids) {
var growProbability = 1,
maxPlants = 40,
plantCount = 0;
for ( m = boids.length - 1; m >= 0; m-- ) {
if (boids[m].type === "plant") {
plantCount++;
}
}
if (plantCount <= maxPlants) {
if (random(0,100) <= growProbability) {
birthedBoid = new Plant(
this.x + random(-this.personalSpace, this.personalSpace),
this.y + random(-this.personalSpace, this.personalSpace)
);
birthedBoid.color = this.color;
boids.push(birthedBoid);
}
}
};
Plant.prototype.draw = function(ctx) {
var drawSize = this.size + this.health;
ctx.fillStyle = this.color;
ctx.shadowBlur = 40;
ctx.shadowColor = this.color;
ctx.fillRect(this.x - drawSize, this.y + drawSize, drawSize, drawSize);
};
/***********************
SIM
***********************/
var boids = [];
var sim = Sketch.create({
container: document.getElementById( 'container' )
});
sim.setup = function() {
for ( i = 0; i < 50; i++ ) {
x = random(0, sim.width);
y = random(0, sim.height);
sim.spawn( x, y);
}
};
sim.spawn = function( x, y) {
var predatorProbability = 0.1,
plantProbability = 0.3;
switch(getRandomItem(['boid','predator','plant'],[1 - predatorProbability - plantProbability, predatorProbability, plantProbability])) {
case 'predator':
boid = new Predator(x, y);
break;
case 'plant':
boid = new Plant(x, y);
break;
default:
boid = new Boid(x, y);
break;
}
boids.push( boid );
};
sim.update = function() {
for ( i = boids.length - 1; i >= 0; i-- ) {
if (boids[i].alive) {
boids[i].ai(boids, i, sim);
boids[i].move();
boids[i].metabolism();
boids[i].mitosis(boids);
} else {
//remove dead boid
boids.splice(i,1);
}
}
};
sim.draw = function() {
sim.globalCompositeOperation = 'lighter';
for ( i = boids.length - 1; i >= 0; i-- ) {
boids[i].draw( sim );
}
sim.fillText(boids.length, 20, 20);
};
!
