canvas = { replay; // set variables var start = Date.now(); let timer = null; var freq_h = []; var freq_d = []; var time = []; const h = 250; // set population var population = d3.range(ne).map(function (d, i) { return { x: w * Math.random(), y: h * Math.random(), dx: (Math.random() - 0.5) * speed, dy: (Math.random() - 0.5) * speed, r: 10, status: -1 * (Math.random() - p), // <0 dove, >0 hawk isColliding: false }; }); // create canvas var canvas = document.createElement("canvas"); canvas.width = w + 10; canvas.height = h + 10; var context = canvas.getContext("2d"); // function that draw a single node in a population function drawNode(d) { context.beginPath(); if (d.status > 0) { context.fillStyle = "Red"; } else { context.fillStyle = "#63ACBE"; } context.arc(d.x, d.y, d.r, 0, d.r * Math.PI); context.fill(); } // function that update nodes location function updateNode(d) { d.x += d.dx; if (d.x > w) { d.x = w; d.dx = -d.dx; } // right else if (d.x < 0) { d.x = 0; d.dx = -d.dx; } // left d.y += d.dy; if (d.y > h) { d.dy = -d.dy; d.y = h; } // bottom else if (d.y < 0) { d.dy = -d.dy; d.y = 0; } // top drawNode(d); } // function that calculate the frequency function updatePlot() { var cntHawk = 0; for (var i = 0; i < population.length; i++) { if (population[i].status > 0) { cntHawk = cntHawk + 1; } } var freq = (cntHawk / population.length).toFixed(2); freq_h.push(freq); freq_d.push(1 - freq); time.push(time.length); viewof plot.value = [time, freq_h, freq_d]; } // function to dettect collision between two nodess function detectCollision(n1, n2, isfirst) { // Calculate the distance between the two circles let squareDistance = (n1.x - n2.x) * (n1.x - n2.x) + (n1.y - n2.y) * (n1.y - n2.y); // when colliding if (squareDistance <= 2 * n1.r * (2 * n2.r)) { if (isfirst) { n2.x = w * Math.random(); n2.y = w * Math.random(); } if (n1.isColliding == false || n2.isColliding == false) { n1.isColliding = true; n2.isColliding = true; n1.dx = -1 * n1.dx; n1.dy = -1 * n1.dy; n2.dx = -1 * n2.dx; n2.dy = -1 * n2.dy; // h * h if (n1.status > 0 && n2.status > 0) { // change both to dove n1.status = -1 * n1.status; n2.status = -1 * n2.status; // h * d } else if ( (n1.status > 0 && n2.status < 0) || (n1.status < 0 && n2.status > 0) ) { if (n1.status < 0) { n1.status = -1 * n1.status; } else { n2.status = -1 * n2.status; } } } } else { n1.isColliding = false; n2.isColliding = false; } } for (var i = 0; i < population.length; i++) { for (var j = i + 1; j < population.length; j++) { detectCollision(population[i], population[j], true); } } timer = d3.timer(ticked); function ticked() { var now = Date.now(), duration = now - start; //if(duration % 500 ==0){ updatePlot(); //} // Update the circle positions. context.clearRect(0, 0, w + 10, h + 10); context.save(); // check collisions for (var i = 0; i < population.length; i++) { for (var j = i + 1; j < population.length; j++) { detectCollision(population[i], population[j], false); } } population.forEach(function (d) { updateNode(d); }); context.restore(); } return canvas; }