<script src="https://cdn.jsdelivr.net/npm/three@0.98.0/build/three.min.js"></script>
<script src="https://cdn.jsdelivr.net/npm/three@0.98.0/examples/js/controls/OrbitControls.js"></script>
<script>
  function getFlameMaterial(isFrontSide){
    let side = isFrontSide ? THREE.FrontSide : THREE.BackSide;
    return new THREE.ShaderMaterial({
      uniforms: {
        time: {value: 0}
      },
      vertexShader: `
        uniform float time;
        varying vec2 vUv;
        varying float hValue;

        //https://thebookofshaders.com/11/
        // 2D Random
        float random (in vec2 st) {
            return fract(sin(dot(st.xy,
                                 vec2(12.9898,78.233)))
                         * 43758.5453123);
        }

        // 2D Noise based on Morgan McGuire @morgan3d
        // https://www.shadertoy.com/view/4dS3Wd
        float noise (in vec2 st) {
            vec2 i = floor(st);
            vec2 f = fract(st);

            // Four corners in 2D of a tile
            float a = random(i);
            float b = random(i + vec2(1.0, 0.0));
            float c = random(i + vec2(0.0, 1.0));
            float d = random(i + vec2(1.0, 1.0));

            // Smooth Interpolation

            // Cubic Hermine Curve.  Same as SmoothStep()
            vec2 u = f*f*(3.0-2.0*f);
            // u = smoothstep(0.,1.,f);

            // Mix 4 coorners percentages
            return mix(a, b, u.x) +
                    (c - a)* u.y * (1.0 - u.x) +
                    (d - b) * u.x * u.y;
        }

        void main() {
          vUv = uv;
          vec3 pos = position;

          pos *= vec3(0.8, 2, 0.725);
          hValue = position.y;
          //float sinT = sin(time * 2.) * 0.5 + 0.5;
          float posXZlen = length(position.xz);

          pos.y *= 1. + (cos((posXZlen + 0.25) * 3.1415926) * 0.25 + noise(vec2(0, time)) * 0.125 + noise(vec2(position.x + time, position.z + time)) * 0.5) * position.y; // flame height

          pos.x += noise(vec2(time * 2., (position.y - time) * 4.0)) * hValue * 0.0312; // flame trembling
          pos.z += noise(vec2((position.y - time) * 4.0, time * 2.)) * hValue * 0.0312; // flame trembling

          gl_Position = projectionMatrix * modelViewMatrix * vec4(pos,1.0);
        }
      `,
      fragmentShader: `
        varying float hValue;
        varying vec2 vUv;

        // honestly stolen from https://www.shadertoy.com/view/4dsSzr
        vec3 heatmapGradient(float t) {
          return clamp((pow(t, 1.5) * 0.8 + 0.2) * vec3(smoothstep(0.0, 0.35, t) + t * 0.5, smoothstep(0.5, 1.0, t), max(1.0 - t * 1.7, t * 7.0 - 6.0)), 0.0, 1.0);
        }

        void main() {
          float v = abs(smoothstep(0.0, 0.4, hValue) - 1.);
          float alpha = (1. - v) * 0.99; // bottom transparency
          alpha -= 1. - smoothstep(1.0, 0.97, hValue); // tip transparency
          gl_FragColor = vec4(heatmapGradient(smoothstep(0.0, 0.3, hValue)) * vec3(0.95,0.95,0.4), alpha) ;
          gl_FragColor.rgb = mix(vec3(0,0,1), gl_FragColor.rgb, smoothstep(0.0, 0.3, hValue)); // blueish for bottom
          gl_FragColor.rgb += vec3(1, 0.9, 0.5) * (1.25 - vUv.y); // make the midst brighter
          gl_FragColor.rgb = mix(gl_FragColor.rgb, vec3(0.66, 0.32, 0.03), smoothstep(0.95, 1., hValue)); // tip
        }
      `,
      transparent: true,
      side: side
    });
  }
</script>
<div id="info" style="position: absolute;width:62px; height: 62px; top: 5px; left: 5px; overflow: hidden; margin:0; padding: 0">
  <div id="circle" class="noselect">i</div>
  <div id="title" style="position: absolute; left: 64px; font-family: Arial; font-size:52px; font-weight:bold; font-style:italic; color: orange;">
    The lonely candle <a style="font-size:10px;" href="http://west77.ru" target="blank">from the warlock's cave</a>
  </div>
  <iframe width="100%" height="150" scrolling="no" frameborder="no" src="https://w.soundcloud.com/player/?url=https%3A//api.soundcloud.com/tracks/77092712&amp;color=%23FFA500&amp;auto_play=true&amp;hide_related=true&amp;show_comments=false&amp;show_user=true&amp;show_reposts=false&amp;show_teaser=false&amp;visual=true"
  style="position:absolute; top:64px;"></iframe>
</div>
body{
  overflow: hidden;
  margin: 0;
}

#circle {
  position: absolute;
  text-align: center;
  width: 60px;
  height: 60px;
  -webkit-border-radius: 30px;
  -moz-border-radius: 30px;
  border-radius: 30px;
  background: rgba(255, 165, 0, 0.5);
  font-size: 50px;
  font-family: Times New Roman;
  color: rgba(255, 165, 0, 1);
  cursor: pointer;
}

.noselect {
  -webkit-touch-callout: none;
  /* iOS Safari */
  -webkit-user-select: none;
  /* Safari */
  -khtml-user-select: none;
  /* Konqueror HTML */
  -moz-user-select: none;
  /* Firefox */
  -ms-user-select: none;
  /* Internet Explorer/Edge */
  user-select: none;
  /* Non-prefixed version, currently
  supported by Chrome and Opera */
}


/* unvisited link */

a:link {
  color: orange;
}


/* visited link */

a:visited {
  color: orange;
}


/* mouse over link */

a:hover {
  color: orange;
}


/* selected link */

a:active {
  color: orange;
}
var hide = true;
circle.addEventListener("click", function() {
  if (hide) {
    circle.style.background = "darkorange";
    circle.style.color = "orange";
    info.style.width = "640px";
    info.style.height = "214px";
  } else {
    circle.style.background = "rgba(255, 165, 0, .5)";
    circle.style.color = "rgba(255, 165, 0, 1)";
    info.style.width = "62px";
    info.style.height = "62px";
  }
  hide = !hide;
}, false);

var scene = new THREE.Scene();
var camera = new THREE.PerspectiveCamera(60, window.innerWidth / window.innerHeight, 1, 1000);
camera.position.set(3, 5, 8).setLength(15);
var renderer = new THREE.WebGLRenderer({antialias: true});
renderer.setSize(window.innerWidth, window.innerHeight);
renderer.setClearColor(0x101005);
renderer.shadowMap.enabled = true;
renderer.shadowMap.type = THREE.PCFSoftShadowMap;
document.body.appendChild(renderer.domElement);

var controls = new THREE.OrbitControls(camera, renderer.domElement);
controls.enablePan = false;
controls.minPolarAngle = THREE.Math.degToRad(60);
controls.maxPolarAngle = THREE.Math.degToRad(95);
controls.minDistance = 4;
controls.maxDistance = 20;
controls.autoRotate = true;
controls.autoRotateSpeed = 1;
controls.target.set(0, 2, 0);
controls.update();

//scene.add(new THREE.GridHelper(10, 10, 0x552222, 0x333322));

var light = new THREE.DirectionalLight(0xffffff, 0.025);
light.position.setScalar(10);
scene.add(light);
scene.add(new THREE.AmbientLight(0xffffff, 0.0625));


// candle
var casePath = new THREE.Path();
casePath.moveTo(0, 0);
casePath.lineTo(0, 0);
casePath.absarc(1.5, 0.5, 0.5, Math.PI * 1.5, Math.PI * 2);
casePath.lineTo(2, 1.5);
casePath.lineTo(1.99, 1.5);
casePath.lineTo(1.9, 0.5);
var caseGeo = new THREE.LatheBufferGeometry(casePath.getPoints(), 64);
var caseMat = new THREE.MeshStandardMaterial({color: "silver" });
var caseMesh = new THREE.Mesh(caseGeo, caseMat);
caseMesh.castShadow = true;

// paraffin
var paraffinPath = new THREE.Path();
paraffinPath.moveTo(0, -.25);
paraffinPath.lineTo(0, -.25);
paraffinPath.absarc(1, 0, 0.25, Math.PI * 1.5, Math.PI * 2);
paraffinPath.lineTo(1.25, 0);
paraffinPath.absarc(1.89, 0.1, 0.1, Math.PI * 1.5, Math.PI * 2);
var paraffinGeo = new THREE.LatheBufferGeometry(paraffinPath.getPoints(), 64);
paraffinGeo.translate(0, 1.25, 0);
var paraffinMat = new THREE.MeshStandardMaterial({color: 0xffff99, side: THREE.BackSide, metalness: 0, roughness: 0.75});
var paraffinMesh = new THREE.Mesh(paraffinGeo, paraffinMat);
caseMesh.add(paraffinMesh);

// candlewick
var candlewickProfile = new THREE.Shape();
candlewickProfile.absarc(0, 0, 0.0625, 0, Math.PI * 2);

var candlewickCurve = new THREE.CatmullRomCurve3([
  new THREE.Vector3(0, 0, 0),
  new THREE.Vector3(0, 0.5, -0.0625),
  new THREE.Vector3(0.25, 0.5, 0.125)
]);

var candlewickGeo = new THREE.ExtrudeBufferGeometry(candlewickProfile, {
	steps: 8,
	bevelEnabled: false,
  extrudePath: candlewickCurve
});
var colors = [];
var color1 = new THREE.Color("black");
var color2 = new THREE.Color(0x994411);
var color3 = new THREE.Color(0xffff44);
for (let i = 0; i < candlewickGeo.attributes.position.count; i++){
  if (candlewickGeo.attributes.position.getY(i) < 0.4){
    color1.toArray(colors, i * 3);
  }
  else {
    color2.toArray(colors, i * 3);
  };
  if (candlewickGeo.attributes.position.getY(i) < 0.15) color3.toArray(colors, i * 3);
}
candlewickGeo.addAttribute( 'color', new THREE.BufferAttribute( new Float32Array(colors), 3 ) );
candlewickGeo.translate(0, 0.95, 0);
var candlewickMat = new THREE.MeshBasicMaterial({vertexColors: THREE.VertexColors});

var candlewickMesh = new THREE.Mesh(candlewickGeo, candlewickMat);
caseMesh.add(candlewickMesh);

// candle light
var candleLight = new THREE.PointLight(0xffaa33, 1, 5, 2);
candleLight.position.set(0, 3, 0);
candleLight.castShadow = true; 
caseMesh.add(candleLight);
var candleLight2 = new THREE.PointLight(0xffaa33, 1, 10, 2);
candleLight2.position.set(0, 4, 0);
candleLight2.castShadow = true;
caseMesh.add(candleLight2);
//scene.add(new THREE.PointLightHelper(candleLight2));

// flame
var flameMaterials = [];
function flame(isFrontSide){
  let flameGeo = new THREE.SphereBufferGeometry(0.5, 32, 32);
  flameGeo.translate(0, 0.5, 0);
  let flameMat = getFlameMaterial(true);
  flameMaterials.push(flameMat);
  let flame = new THREE.Mesh(flameGeo, flameMat);
  flame.position.set(0.06, 1.2, 0.06);
  flame.rotation.y = THREE.Math.degToRad(-45);
  caseMesh.add(flame);
}

flame(false);
flame(true);

// table
var tableGeo = new THREE.CylinderBufferGeometry(14, 14, 0.5, 64);
tableGeo.translate(0, -0.25, 0);
var tableMat = new THREE.MeshStandardMaterial({map: new THREE.TextureLoader().load("https://threejs.org/examples/textures/hardwood2_diffuse.jpg"), metalness: 0, roughness: 0.75});
var tableMesh = new THREE.Mesh(tableGeo, tableMat);
tableMesh.receiveShadow = true;

tableMesh.add(caseMesh);
scene.add(tableMesh);

// pentagram
/*var penta = new THREE.CircleGeometry(7, 5);
penta.rotateX(-Math.PI * 0.5);
penta.vertices.shift();
var pentagramGeo = new THREE.BufferGeometry().setFromPoints(penta.vertices);
pentagramGeo.setIndex([0,1, 1,2, 2,3, 3,4, 4,0, 0,2, 2,4, 4,1, 1,3, 3,0]);
var pentagram = new THREE.LineSegments(pentagramGeo, new THREE.LineBasicMaterial({color: 0xff3311}));
pentagram.y = 0.01;
scene.add(pentagram);*/


var clock = new THREE.Clock();
var time = 0;

render();
function render(){
  requestAnimationFrame(render);
  time += clock.getDelta();
  flameMaterials[0].uniforms.time.value = time;
  flameMaterials[1].uniforms.time.value = time;
  candleLight2.position.x = Math.sin(time * Math.PI) * 0.25;
  candleLight2.position.z = Math.cos(time * Math.PI * 0.75) * 0.25;
  candleLight2.intensity = 2 + Math.sin(time * Math.PI * 2) * Math.cos(time * Math.PI * 1.5) * 0.25;
  controls.update();
  renderer.render(scene, camera);
}
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