var can; var c; var lines; var frame; var target; window.onload = function(){ can = document.getElementById("can"); can.width = Math.min(window.innerWidth, window.innerHeight); can.height = can.width; c = can.getContext("2d"); can.addEventListener("mousedown", function(e){ var rect = can.getBoundingClientRect(); var x = (e.clientX - rect.left) / can.width; var y = (e.clientY - rect.top) / can.height; target = new Target(x, y); }); can.addEventListener("touchstart", function(e){ var rect = can.getBoundingClientRect(); var x = (e.touches[0].clientX - rect.left) / can.width; var y = (e.touches[0].clientY - rect.top) / can.height; target = new Target(x, y); }); frame = 1; lines = []; for(var i=0;i<6;i++){ lines.push(new Line()); } target = null; loop(); } window.onresize = function(){ can.width = Math.min(window.innerWidth, window.innerHeight); can.height = can.width; c = can.getContext("2d"); } function loop(){ c.fillStyle = "rgba(0, 0, 0, 1)"; c.fillRect(0, 0, can.width, can.height); for(var i=0;i 2*Math.PI){ this.angle -= 2*Math.PI; }else if(this.angle < 0){ this.angle += 2*Math.PI; } this.x += Math.cos(this.angle) * this.speed; this.y += Math.sin(this.angle) * this.speed; var jumped = this.edgeJump(); this.updatePoints(jumped); this.updateParticles(); } this.updateParticles = function(){ if(Math.random() < 0.1){ this.particles.push(new Particle(this.x, this.y, this.colorStep)); } for(var i=0;i 0){ if(this.particles[0].shouldBeRemoved()){ this.particles.splice(0, 1); } } } this.edgeJump = function(){ var jumped = false; if(this.x < 0){ this.x += 1; jumped = true; }else if(this.x > 1){ this.x -= 1; jumped = true; } if(this.y < 0){ this.y += 1; jumped = true; }else if(this.y > 1){ this.y -= 1; jumped = true; } return jumped; } this.updatePoints = function(jumped){ //adding if(jumped){ this.points.push([[this.x, this.y]]); }else{ this.points[this.points.length-1].push([this.x, this.y]); } //removing if(this.points[0].length > 0){ this.points[0].splice(0, 1); }else{ this.points.splice(0, 1); this.points[0].splice(0, 1); } } this.render = function(c, width, height){ var headSize = width/25; var point = 0; for(var i=0;i 0 && seed < 1) { // Scale the seed out seed *= 65536; } seed = Math.floor(seed); if(seed < 256) { seed |= seed << 8; } for(var i = 0; i < 256; i++) { var v; if (i & 1) { v = p[i] ^ (seed & 255); } else { v = p[i] ^ ((seed>>8) & 255); } perm[i] = perm[i + 256] = v; gradP[i] = gradP[i + 256] = grad3[v % 12]; } }; module.seed(0); /* for(var i=0; i<256; i++) { perm[i] = perm[i + 256] = p[i]; gradP[i] = gradP[i + 256] = grad3[perm[i] % 12]; }*/ // Skewing and unskewing factors for 2, 3, and 4 dimensions var F2 = 0.5*(Math.sqrt(3)-1); var G2 = (3-Math.sqrt(3))/6; var F3 = 1/3; var G3 = 1/6; // 2D simplex noise module.simplex2 = function(xin, yin) { var n0, n1, n2; // Noise contributions from the three corners // Skew the input space to determine which simplex cell we're in var s = (xin+yin)*F2; // Hairy factor for 2D var i = Math.floor(xin+s); var j = Math.floor(yin+s); var t = (i+j)*G2; var x0 = xin-i+t; // The x,y distances from the cell origin, unskewed. var y0 = yin-j+t; // For the 2D case, the simplex shape is an equilateral triangle. // Determine which simplex we are in. var i1, j1; // Offsets for second (middle) corner of simplex in (i,j) coords if(x0>y0) { // lower triangle, XY order: (0,0)->(1,0)->(1,1) i1=1; j1=0; } else { // upper triangle, YX order: (0,0)->(0,1)->(1,1) i1=0; j1=1; } // A step of (1,0) in (i,j) means a step of (1-c,-c) in (x,y), and // a step of (0,1) in (i,j) means a step of (-c,1-c) in (x,y), where // c = (3-sqrt(3))/6 var x1 = x0 - i1 + G2; // Offsets for middle corner in (x,y) unskewed coords var y1 = y0 - j1 + G2; var x2 = x0 - 1 + 2 * G2; // Offsets for last corner in (x,y) unskewed coords var y2 = y0 - 1 + 2 * G2; // Work out the hashed gradient indices of the three simplex corners i &= 255; j &= 255; var gi0 = gradP[i+perm[j]]; var gi1 = gradP[i+i1+perm[j+j1]]; var gi2 = gradP[i+1+perm[j+1]]; // Calculate the contribution from the three corners var t0 = 0.5 - x0*x0-y0*y0; if(t0<0) { n0 = 0; } else { t0 *= t0; n0 = t0 * t0 * gi0.dot2(x0, y0); // (x,y) of grad3 used for 2D gradient } var t1 = 0.5 - x1*x1-y1*y1; if(t1<0) { n1 = 0; } else { t1 *= t1; n1 = t1 * t1 * gi1.dot2(x1, y1); } var t2 = 0.5 - x2*x2-y2*y2; if(t2<0) { n2 = 0; } else { t2 *= t2; n2 = t2 * t2 * gi2.dot2(x2, y2); } // Add contributions from each corner to get the final noise value. // The result is scaled to return values in the interval [-1,1]. return 70 * (n0 + n1 + n2); }; // 3D simplex noise module.simplex3 = function(xin, yin, zin) { var n0, n1, n2, n3; // Noise contributions from the four corners // Skew the input space to determine which simplex cell we're in var s = (xin+yin+zin)*F3; // Hairy factor for 2D var i = Math.floor(xin+s); var j = Math.floor(yin+s); var k = Math.floor(zin+s); var t = (i+j+k)*G3; var x0 = xin-i+t; // The x,y distances from the cell origin, unskewed. var y0 = yin-j+t; var z0 = zin-k+t; // For the 3D case, the simplex shape is a slightly irregular tetrahedron. // Determine which simplex we are in. var i1, j1, k1; // Offsets for second corner of simplex in (i,j,k) coords var i2, j2, k2; // Offsets for third corner of simplex in (i,j,k) coords if(x0 >= y0) { if(y0 >= z0) { i1=1; j1=0; k1=0; i2=1; j2=1; k2=0; } else if(x0 >= z0) { i1=1; j1=0; k1=0; i2=1; j2=0; k2=1; } else { i1=0; j1=0; k1=1; i2=1; j2=0; k2=1; } } else { if(y0 < z0) { i1=0; j1=0; k1=1; i2=0; j2=1; k2=1; } else if(x0 < z0) { i1=0; j1=1; k1=0; i2=0; j2=1; k2=1; } else { i1=0; j1=1; k1=0; i2=1; j2=1; k2=0; } } // A step of (1,0,0) in (i,j,k) means a step of (1-c,-c,-c) in (x,y,z), // a step of (0,1,0) in (i,j,k) means a step of (-c,1-c,-c) in (x,y,z), and // a step of (0,0,1) in (i,j,k) means a step of (-c,-c,1-c) in (x,y,z), where // c = 1/6. var x1 = x0 - i1 + G3; // Offsets for second corner var y1 = y0 - j1 + G3; var z1 = z0 - k1 + G3; var x2 = x0 - i2 + 2 * G3; // Offsets for third corner var y2 = y0 - j2 + 2 * G3; var z2 = z0 - k2 + 2 * G3; var x3 = x0 - 1 + 3 * G3; // Offsets for fourth corner var y3 = y0 - 1 + 3 * G3; var z3 = z0 - 1 + 3 * G3; // Work out the hashed gradient indices of the four simplex corners i &= 255; j &= 255; k &= 255; var gi0 = gradP[i+ perm[j+ perm[k ]]]; var gi1 = gradP[i+i1+perm[j+j1+perm[k+k1]]]; var gi2 = gradP[i+i2+perm[j+j2+perm[k+k2]]]; var gi3 = gradP[i+ 1+perm[j+ 1+perm[k+ 1]]]; // Calculate the contribution from the four corners var t0 = 0.6 - x0*x0 - y0*y0 - z0*z0; if(t0<0) { n0 = 0; } else { t0 *= t0; n0 = t0 * t0 * gi0.dot3(x0, y0, z0); // (x,y) of grad3 used for 2D gradient } var t1 = 0.6 - x1*x1 - y1*y1 - z1*z1; if(t1<0) { n1 = 0; } else { t1 *= t1; n1 = t1 * t1 * gi1.dot3(x1, y1, z1); } var t2 = 0.6 - x2*x2 - y2*y2 - z2*z2; if(t2<0) { n2 = 0; } else { t2 *= t2; n2 = t2 * t2 * gi2.dot3(x2, y2, z2); } var t3 = 0.6 - x3*x3 - y3*y3 - z3*z3; if(t3<0) { n3 = 0; } else { t3 *= t3; n3 = t3 * t3 * gi3.dot3(x3, y3, z3); } // Add contributions from each corner to get the final noise value. // The result is scaled to return values in the interval [-1,1]. return 32 * (n0 + n1 + n2 + n3); }; // ##### Perlin noise stuff function fade(t) { return t*t*t*(t*(t*6-15)+10); } function lerp(a, b, t) { return (1-t)*a + t*b; } // 2D Perlin Noise module.perlin2 = function(x, y) { // Find unit grid cell containing point var X = Math.floor(x), Y = Math.floor(y); // Get relative xy coordinates of point within that cell x = x - X; y = y - Y; // Wrap the integer cells at 255 (smaller integer period can be introduced here) X = X & 255; Y = Y & 255; // Calculate noise contributions from each of the four corners var n00 = gradP[X+perm[Y]].dot2(x, y); var n01 = gradP[X+perm[Y+1]].dot2(x, y-1); var n10 = gradP[X+1+perm[Y]].dot2(x-1, y); var n11 = gradP[X+1+perm[Y+1]].dot2(x-1, y-1); // Compute the fade curve value for x var u = fade(x); // Interpolate the four results return lerp( lerp(n00, n10, u), lerp(n01, n11, u), fade(y)); }; // 3D Perlin Noise module.perlin3 = function(x, y, z) { // Find unit grid cell containing point var X = Math.floor(x), Y = Math.floor(y), Z = Math.floor(z); // Get relative xyz coordinates of point within that cell x = x - X; y = y - Y; z = z - Z; // Wrap the integer cells at 255 (smaller integer period can be introduced here) X = X & 255; Y = Y & 255; Z = Z & 255; // Calculate noise contributions from each of the eight corners var n000 = gradP[X+ perm[Y+ perm[Z ]]].dot3(x, y, z); var n001 = gradP[X+ perm[Y+ perm[Z+1]]].dot3(x, y, z-1); var n010 = gradP[X+ perm[Y+1+perm[Z ]]].dot3(x, y-1, z); var n011 = gradP[X+ perm[Y+1+perm[Z+1]]].dot3(x, y-1, z-1); var n100 = gradP[X+1+perm[Y+ perm[Z ]]].dot3(x-1, y, z); var n101 = gradP[X+1+perm[Y+ perm[Z+1]]].dot3(x-1, y, z-1); var n110 = gradP[X+1+perm[Y+1+perm[Z ]]].dot3(x-1, y-1, z); var n111 = gradP[X+1+perm[Y+1+perm[Z+1]]].dot3(x-1, y-1, z-1); // Compute the fade curve value for x, y, z var u = fade(x); var v = fade(y); var w = fade(z); // Interpolate return lerp( lerp( lerp(n000, n100, u), lerp(n001, n101, u), w), lerp( lerp(n010, n110, u), lerp(n011, n111, u), w), v); }; })(this);

oddly satisfying || using noise