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Here you can Sed posuere consectetur est at lobortis. Donec ullamcorper nulla non metus auctor fringilla. Maecenas sed diam eget risus varius blandit sit amet non magna. Donec id elit non mi porta gravida at eget metus. Praesent commodo cursus magna, vel scelerisque nisl consectetur et.

            
              <body>
  <canvas id="canvas" width="1400" height="600"></canvas>
</body>
            
          
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              body {
  background-color: #000;    
  margin: 0;
  overflow: hidden;
  background-repeat: no-repeat;
}
            
          
!
            
              var canvas = document.getElementById("canvas");

canvas.width = window.innerWidth;
canvas.height = window.innerHeight;

// Initialize the GL context
var gl = canvas.getContext('webgl');
if(!gl){
  console.error("Unable to initialize WebGL.");
}

//Time
var time = 0.0;

//************** Shader sources **************

var vertexSource = `
attribute vec2 position;
void main() {
	gl_Position = vec4(position, 0.0, 1.0);
}
`;

var fragmentSource = `
precision highp float;

uniform float width;
uniform float height;
vec2 resolution = vec2(width, height);

uniform float time;

#define POINT_COUNT 8

vec2 points[POINT_COUNT];
const float speed = -0.7;
const float len = 0.25;
float intensity = 0.9;
float radius = 0.02;

//https://www.shadertoy.com/view/MlKcDD
//Signed distance to a quadratic bezier
float sdBezier(vec2 pos, vec2 A, vec2 B, vec2 C){    
	vec2 a = B - A;
	vec2 b = A - 2.0*B + C;
	vec2 c = a * 2.0;
	vec2 d = A - pos;

	float kk = 1.0 / dot(b,b);
	float kx = kk * dot(a,b);
	float ky = kk * (2.0*dot(a,a)+dot(d,b)) / 3.0;
	float kz = kk * dot(d,a);      

	float res = 0.0;

	float p = ky - kx*kx;
	float p3 = p*p*p;
	float q = kx*(2.0*kx*kx - 3.0*ky) + kz;
	float h = q*q + 4.0*p3;

	if(h >= 0.0){ 
		h = sqrt(h);
		vec2 x = (vec2(h, -h) - q) / 2.0;
		vec2 uv = sign(x)*pow(abs(x), vec2(1.0/3.0));
		float t = uv.x + uv.y - kx;
		t = clamp( t, 0.0, 1.0 );

		// 1 root
		vec2 qos = d + (c + b*t)*t;
		res = length(qos);
	}else{
		float z = sqrt(-p);
		float v = acos( q/(p*z*2.0) ) / 3.0;
		float m = cos(v);
		float n = sin(v)*1.732050808;
		vec3 t = vec3(m + m, -n - m, n - m) * z - kx;
		t = clamp( t, 0.0, 1.0 );

		// 3 roots
		vec2 qos = d + (c + b*t.x)*t.x;
		float dis = dot(qos,qos);
        
		res = dis;

		qos = d + (c + b*t.y)*t.y;
		dis = dot(qos,qos);
		res = min(res,dis);
		
		qos = d + (c + b*t.z)*t.z;
		dis = dot(qos,qos);
		res = min(res,dis);

		res = sqrt( res );
	}
    
	return res;
}

//http://mathworld.wolfram.com/Lemniscate.html
vec2 getLemniscatePosition(float t){
	//Set the width of the lemniscate to depend on the location parameter, leading to a skewed path
	float a = (1.0 + 0.5 + 0.5 * sin(t)) * 15.0;

	return vec2((a * cos(t)) / (1.0 + (sin(t) * sin(t))), (a * sin(t) * cos(t))/ (1.0 + (sin(t) * sin(t))));
}

//https://www.shadertoy.com/view/3s3GDn
float getGlow(float dist, float radius, float intensity){
	return pow(radius/dist, intensity);
}

float getSegment(float t, vec2 pos, float offset, float scale){
	for(int i = 0; i < POINT_COUNT; i++){
		points[i] = getLemniscatePosition(offset + float(i)*len + fract(speed * t) * 6.28);
	}
    
	vec2 c = (points[0] + points[1]) / 2.0;
	vec2 c_prev;
	float dist = 10000.0;
    
	for(int i = 0; i < POINT_COUNT-1; i++){
		//https://tinyurl.com/y2htbwkm
		c_prev = c;
		c = (points[i] + points[i+1]) / 2.0;
		dist = min(dist, sdBezier(pos, scale * c_prev, scale * points[i], scale * c));
	}
	return max(0.0, dist);
}

void main(){
	vec2 uv = gl_FragCoord.xy/resolution.xy;
	float widthHeightRatio = resolution.x/resolution.y;
	vec2 centre = vec2(0.5, 0.5);
	vec2 pos = centre - uv;
	pos.y /= widthHeightRatio;
	float scale = 0.000015 * height;
	
	float t = time;
    
	//Get first segment
	float dist = getSegment(t, pos, 0.0, scale);
	float glow = getGlow(dist, radius, intensity);
    
	vec3 col = vec3(0.0);
    
	//White core
    col += 10.0*vec3(smoothstep(0.003, 0.001, dist));
    //Purple glow
    col += glow * vec3(0.7, 0.3, 0.9);
    
    //Get second segment
    dist = getSegment(t, pos, 3.7, scale);
    glow = getGlow(dist, radius, intensity);
    
    //White core
    col += 10.0*vec3(smoothstep(0.003, 0.001, dist));
    //Blue glow
    col += glow * vec3(0.3, 0.5, 0.9);
        
	//Tone mapping
	col = 1.0 - exp(-col);

	//Output to screen
 	gl_FragColor = vec4(col,1.0);
}
`;

//************** Utility functions **************

window.addEventListener('resize', onWindowResize, false);

function onWindowResize(){
  canvas.width  = window.innerWidth;
  canvas.height = window.innerHeight;
	gl.viewport(0, 0, canvas.width, canvas.height);
  gl.uniform1f(widthHandle, window.innerWidth);
  gl.uniform1f(heightHandle, window.innerHeight);
}


//Compile shader and combine with source
function compileShader(shaderSource, shaderType){
  var shader = gl.createShader(shaderType);
  gl.shaderSource(shader, shaderSource);
  gl.compileShader(shader);
  if(!gl.getShaderParameter(shader, gl.COMPILE_STATUS)){
  	throw "Shader compile failed with: " + gl.getShaderInfoLog(shader);
  }
  return shader;
}

//From https://codepen.io/jlfwong/pen/GqmroZ
//Utility to complain loudly if we fail to find the attribute/uniform
function getAttribLocation(program, name) {
  var attributeLocation = gl.getAttribLocation(program, name);
  if (attributeLocation === -1) {
  	throw 'Cannot find attribute ' + name + '.';
  }
  return attributeLocation;
}

function getUniformLocation(program, name) {
  var attributeLocation = gl.getUniformLocation(program, name);
  if (attributeLocation === -1) {
  	throw 'Cannot find uniform ' + name + '.';
  }
  return attributeLocation;
}

//************** Create shaders **************

//Create vertex and fragment shaders
var vertexShader = compileShader(vertexSource, gl.VERTEX_SHADER);
var fragmentShader = compileShader(fragmentSource, gl.FRAGMENT_SHADER);

//Create shader programs
var program = gl.createProgram();
gl.attachShader(program, vertexShader);
gl.attachShader(program, fragmentShader);
gl.linkProgram(program);

gl.useProgram(program);

//Set up rectangle covering entire canvas 
var vertexData = new Float32Array([
  -1.0,  1.0, 	// top left
  -1.0, -1.0, 	// bottom left
   1.0,  1.0, 	// top right
   1.0, -1.0, 	// bottom right
]);

//Create vertex buffer
var vertexDataBuffer = gl.createBuffer();
gl.bindBuffer(gl.ARRAY_BUFFER, vertexDataBuffer);
gl.bufferData(gl.ARRAY_BUFFER, vertexData, gl.STATIC_DRAW);

// Layout of our data in the vertex buffer
var positionHandle = getAttribLocation(program, 'position');

gl.enableVertexAttribArray(positionHandle);
gl.vertexAttribPointer(positionHandle,
  2, 				// position is a vec2 (2 values per component)
  gl.FLOAT, // each component is a float
  false, 		// don't normalize values
  2 * 4, 		// two 4 byte float components per vertex (32 bit float is 4 bytes)
  0 				// how many bytes inside the buffer to start from
  );

//Set uniform handle
var timeHandle = getUniformLocation(program, 'time');
var widthHandle = getUniformLocation(program, 'width');
var heightHandle = getUniformLocation(program, 'height');

gl.uniform1f(widthHandle, window.innerWidth);
gl.uniform1f(heightHandle, window.innerHeight);

var lastFrame = Date.now();
var thisFrame;

function draw(){
	
  //Update time
	thisFrame = Date.now();
  time += (thisFrame - lastFrame)/1000;	
	lastFrame = thisFrame;

	//Send uniforms to program
  gl.uniform1f(timeHandle, time);
  //Draw a triangle strip connecting vertices 0-4
  gl.drawArrays(gl.TRIANGLE_STRIP, 0, 4);

  requestAnimationFrame(draw);
}

draw();
            
          
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