Добавление скриптов на сайт

<script>
$(".tn-elem__1124471441561486338259 .tn-atom").append("<canvas class='paints'></canvas>")
</script>

<style>
.paints {
height: 100vh;
width: 100vw;
}
</style>

<script>
'use strict';

const canvas = document.getElementsByTagName('canvas')[0];
canvas.width = canvas.clientWidth;
canvas.height = canvas.clientHeight;

let config = {
SIM_RESOLUTION: 128,
DYE_RESOLUTION: 512,
DENSITY_DISSIPATION: 0.97,
VELOCITY_DISSIPATION: 0.98,
PRESSURE_DISSIPATION: 0.8,
PRESSURE_ITERATIONS: 20,
CURL: 30,
SPLAT_RADIUS: 0.5,
SHADING: true,
COLORFUL: true,
PAUSED: false,
BACK_COLOR: { r: 0, g:0, b: 0 },
TRANSPARENT: false,
BLOOM: true,
BLOOM_ITERATIONS: 8,
BLOOM_RESOLUTION: 256,
BLOOM_INTENSITY: 0.8,
BLOOM_THRESHOLD: 0.6,
BLOOM_SOFT_KNEE: 0.7
}

function pointerPrototype () {
this.id = -1;
this.x = 0;
this.y = 0;
this.dx = 0;
this.dy = 0;
this.down = false;
this.moved = false;
this.color = [30, 0, 300];
}

let pointers = [];
let splatStack = [];
let bloomFramebuffers = [];
pointers.push(new pointerPrototype());

const { gl, ext } = getWebGLContext(canvas);

if (isMobile())
config.SHADING = false;
if (!ext.supportLinearFiltering)
{
config.SHADING = false;
config.BLOOM = false;
}

function getWebGLContext (canvas) {
const params = { alpha: true, depth: false, stencil: false, antialias: false, preserveDrawingBuffer: false };

let gl = canvas.getContext('webgl2', params);
const isWebGL2 = !!gl;
if (!isWebGL2)
gl = canvas.getContext('webgl', params) || canvas.getContext('experimental-webgl', params);

let halfFloat;
let supportLinearFiltering;
if (isWebGL2) {
gl.getExtension('EXT_color_buffer_float');
supportLinearFiltering = gl.getExtension('OES_texture_float_linear');
} else {
halfFloat = gl.getExtension('OES_texture_half_float');
supportLinearFiltering = gl.getExtension('OES_texture_half_float_linear');
}

gl.clearColor(0.0, 0.0, 0.0, 1.0);

const halfFloatTexType = isWebGL2 ? gl.HALF_FLOAT : halfFloat.HALF_FLOAT_OES;
let formatRGBA;
let formatRG;
let formatR;

if (isWebGL2)
{
formatRGBA = getSupportedFormat(gl, gl.RGBA16F, gl.RGBA, halfFloatTexType);
formatRG = getSupportedFormat(gl, gl.RG16F, gl.RG, halfFloatTexType);
formatR = getSupportedFormat(gl, gl.R16F, gl.RED, halfFloatTexType);
}
else
{
formatRGBA = getSupportedFormat(gl, gl.RGBA, gl.RGBA, halfFloatTexType);
formatRG = getSupportedFormat(gl, gl.RGBA, gl.RGBA, halfFloatTexType);
formatR = getSupportedFormat(gl, gl.RGBA, gl.RGBA, halfFloatTexType);
}

return {
gl,
ext: {
formatRGBA,
formatRG,
formatR,
halfFloatTexType,
supportLinearFiltering
}
};
}

function getSupportedFormat (gl, internalFormat, format, type)
{
if (!supportRenderTextureFormat(gl, internalFormat, format, type))
{
switch (internalFormat)
{
case gl.R16F:
return getSupportedFormat(gl, gl.RG16F, gl.RG, type);
case gl.RG16F:
return getSupportedFormat(gl, gl.RGBA16F, gl.RGBA, type);
default:
return null;
}
}

return {
internalFormat,
format
}
}

function supportRenderTextureFormat (gl, internalFormat, format, type) {
let texture = gl.createTexture();
gl.bindTexture(gl.TEXTURE_2D, texture);
gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, gl.NEAREST);
gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, gl.NEAREST);
gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_S, gl.CLAMP_TO_EDGE);
gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_T, gl.CLAMP_TO_EDGE);
gl.texImage2D(gl.TEXTURE_2D, 0, internalFormat, 4, 4, 0, format, type, null);

let fbo = gl.createFramebuffer();
gl.bindFramebuffer(gl.FRAMEBUFFER, fbo);
gl.framebufferTexture2D(gl.FRAMEBUFFER, gl.COLOR_ATTACHMENT0, gl.TEXTURE_2D, texture, 0);

const status = gl.checkFramebufferStatus(gl.FRAMEBUFFER);
if (status != gl.FRAMEBUFFER_COMPLETE)
return false;
return true;
}

function captureScreenshot () {
colorProgram.bind();
gl.uniform4f(colorProgram.uniforms.color, 0, 0, 0, 1);
blit(density.write.fbo);

render(density.write.fbo);
gl.bindFramebuffer(gl.FRAMEBUFFER, density.write.fbo);

let length = dyeWidth * dyeHeight * 4;
let pixels = new Float32Array(length);
gl.readPixels(0, 0, dyeWidth, dyeHeight, gl.RGBA, gl.FLOAT, pixels);

let newPixels = new Uint8Array(length);

let id = 0;
for (let i = dyeHeight - 1; i >= 0; i--) {
for (let j = 0; j < dyeWidth; j++) {
let nid = i * dyeWidth * 4 + j * 4;
newPixels[nid + 0] = clamp01(pixels[id + 0]) * 255;
newPixels[nid + 1] = clamp01(pixels[id + 1]) * 255;
newPixels[nid + 2] = clamp01(pixels[id + 2]) * 255;
newPixels[nid + 3] = clamp01(pixels[id + 3]) * 255;
id += 4;
}
}

let captureCanvas = document.createElement('canvas');
let ctx = captureCanvas.getContext('2d');
captureCanvas.width = dyeWidth;
captureCanvas.height = dyeHeight;

let imageData = ctx.createImageData(dyeWidth, dyeHeight);
imageData.data.set(newPixels);
ctx.putImageData(imageData, 0, 0);
let datauri = captureCanvas.toDataURL();

downloadURI("fluid.png", datauri);

URL.revokeObjectURL(datauri);
}

function clamp01 (input) {
return Math.min(Math.max(input, 0), 1);
}

function downloadURI (filename, uri) {
let link = document.createElement("a");
link.download = filename;
link.href = uri;
document.body.appendChild(link);
link.click();
document.body.removeChild(link);
}

function isMobile () {
return /Mobi|Android/i.test(navigator.userAgent);
}

class GLProgram {
constructor (vertexShader, fragmentShader) {
this.uniforms = {};
this.program = gl.createProgram();

gl.attachShader(this.program, vertexShader);
gl.attachShader(this.program, fragmentShader);
gl.linkProgram(this.program);

if (!gl.getProgramParameter(this.program, gl.LINK_STATUS))
throw gl.getProgramInfoLog(this.program);

const uniformCount = gl.getProgramParameter(this.program, gl.ACTIVE_UNIFORMS);
for (let i = 0; i < uniformCount; i++) {
const uniformName = gl.getActiveUniform(this.program, i).name;
this.uniforms[uniformName] = gl.getUniformLocation(this.program, uniformName);
}
}

bind () {
gl.useProgram(this.program);
}
}

function compileShader (type, source) {
const shader = gl.createShader(type);
gl.shaderSource(shader, source);
gl.compileShader(shader);

if (!gl.getShaderParameter(shader, gl.COMPILE_STATUS))
throw gl.getShaderInfoLog(shader);

return shader;
};

const baseVertexShader = compileShader(gl.VERTEX_SHADER, `
precision highp float;
attribute vec2 aPosition;
varying vec2 vUv;
varying vec2 vL;
varying vec2 vR;
varying vec2 vT;
varying vec2 vB;
uniform vec2 texelSize;
void main () {
vUv = aPosition * 0.5 + 0.5;
vL = vUv - vec2(texelSize.x, 0.0);
vR = vUv + vec2(texelSize.x, 0.0);
vT = vUv + vec2(0.0, texelSize.y);
vB = vUv - vec2(0.0, texelSize.y);
gl_Position = vec4(aPosition, 0.0, 1.0);
}
`);

const clearShader = compileShader(gl.FRAGMENT_SHADER, `
precision mediump float;
precision mediump sampler2D;
varying highp vec2 vUv;
uniform sampler2D uTexture;
uniform float value;
void main () {
gl_FragColor = value * texture2D(uTexture, vUv);
}
`);

const colorShader = compileShader(gl.FRAGMENT_SHADER, `
precision mediump float;
uniform vec4 color;
void main () {
gl_FragColor = color;
}
`);

const backgroundShader = compileShader(gl.FRAGMENT_SHADER, `
precision highp float;
precision highp sampler2D;
varying vec2 vUv;
uniform sampler2D uTexture;
uniform float aspectRatio;
#define SCALE 25.0void main () {
vec2 uv = floor(vUv * SCALE * vec2(aspectRatio, 1.0));
float v = mod(uv.x + uv.y, 2.0);
v = v * 0.1 + 0.8;
gl_FragColor = vec4(vec3(v), 1.0);
}
`);

const displayShader = compileShader(gl.FRAGMENT_SHADER, `
precision highp float;
precision highp sampler2D;
varying vec2 vUv;
uniform sampler2D uTexture;
void main () {
vec3 C = texture2D(uTexture, vUv).rgb;
float a = max(C.r, max(C.g, C.b));
gl_FragColor = vec4(C, a);
}
`);

const displayBloomShader = compileShader(gl.FRAGMENT_SHADER, `
precision highp float;
precision highp sampler2D;
varying vec2 vUv;
uniform sampler2D uTexture;
uniform sampler2D uBloom;
uniform sampler2D uDithering;
uniform vec2 ditherScale;
void main () {
vec3 C = texture2D(uTexture, vUv).rgb;
vec3 bloom = texture2D(uBloom, vUv).rgb;
vec3 noise = texture2D(uDithering, vUv * ditherScale).rgb;
noise = noise * 2.0 - 1.0;
bloom += noise / 800.0;
bloom = pow(bloom.rgb, vec3(1.0 / 2.2));
C += bloom;
float a = max(C.r, max(C.g, C.b));
gl_FragColor = vec4(C, a);
}
`);

const displayShadingShader = compileShader(gl.FRAGMENT_SHADER, `
precision highp float;
precision highp sampler2D;
varying vec2 vUv;
varying vec2 vL;
varying vec2 vR;
varying vec2 vT;
varying vec2 vB;
uniform sampler2D uTexture;
uniform vec2 texelSize;
void main () {
vec3 L = texture2D(uTexture, vL).rgb;
vec3 R = texture2D(uTexture, vR).rgb;
vec3 T = texture2D(uTexture, vT).rgb;
vec3 B = texture2D(uTexture, vB).rgb;
vec3 C = texture2D(uTexture, vUv).rgb;
float dx = length(R) - length(L);
float dy = length(T) - length(B);
vec3 n = normalize(vec3(dx, dy, length(texelSize)));
vec3 l = vec3(0.0, 0.0, 1.0);
float diffuse = clamp(dot(n, l) + 0.7, 0.7, 1.0);
C.rgb *= diffuse;
float a = max(C.r, max(C.g, C.b));
gl_FragColor = vec4(C, a);
}
`);

const displayBloomShadingShader = compileShader(gl.FRAGMENT_SHADER, `
precision highp float;
precision highp sampler2D;
varying vec2 vUv;
varying vec2 vL;
varying vec2 vR;
varying vec2 vT;
varying vec2 vB;
uniform sampler2D uTexture;
uniform sampler2D uBloom;
uniform sampler2D uDithering;
uniform vec2 ditherScale;
uniform vec2 texelSize;
void main () {
vec3 L = texture2D(uTexture, vL).rgb;
vec3 R = texture2D(uTexture, vR).rgb;
vec3 T = texture2D(uTexture, vT).rgb;
vec3 B = texture2D(uTexture, vB).rgb;
vec3 C = texture2D(uTexture, vUv).rgb;
float dx = length(R) - length(L);
float dy = length(T) - length(B);
vec3 n = normalize(vec3(dx, dy, length(texelSize)));
vec3 l = vec3(0.0, 0.0, 1.0);
float diffuse = clamp(dot(n, l) + 0.7, 0.7, 1.0);
C *= diffuse;
vec3 bloom = texture2D(uBloom, vUv).rgb;
vec3 noise = texture2D(uDithering, vUv * ditherScale).rgb;
noise = noise * 2.0 - 1.0;
bloom += noise / 800.0;
bloom = pow(bloom.rgb, vec3(1.0 / 2.2));
C += bloom;
float a = max(C.r, max(C.g, C.b));
gl_FragColor = vec4(C, a);
}
`);

const bloomPrefilterShader = compileShader(gl.FRAGMENT_SHADER, `
precision mediump float;
precision mediump sampler2D;
varying vec2 vUv;
uniform sampler2D uTexture;
uniform vec3 curve;
uniform float threshold;
void main () {
vec3 c = texture2D(uTexture, vUv).rgb;
float br = max(c.r, max(c.g, c.b));
float rq = clamp(br - curve.x, 0.0, curve.y);
rq = curve.z * rq * rq;
c *= max(rq, br - threshold) / max(br, 0.0001);
gl_FragColor = vec4(c, 0.0);
}
`);

const bloomBlurShader = compileShader(gl.FRAGMENT_SHADER, `
precision mediump float;
precision mediump sampler2D;
varying vec2 vL;
varying vec2 vR;
varying vec2 vT;
varying vec2 vB;
uniform sampler2D uTexture;
void main () {
vec4 sum = vec4(0.0);
sum += texture2D(uTexture, vL);
sum += texture2D(uTexture, vR);
sum += texture2D(uTexture, vT);
sum += texture2D(uTexture, vB);
sum *= 0.25;
gl_FragColor = sum;
}
`);

const bloomFinalShader = compileShader(gl.FRAGMENT_SHADER, `
precision mediump float;
precision mediump sampler2D;
varying vec2 vL;
varying vec2 vR;
varying vec2 vT;
varying vec2 vB;
uniform sampler2D uTexture;
uniform float intensity;
void main () {
vec4 sum = vec4(0.0);
sum += texture2D(uTexture, vL);
sum += texture2D(uTexture, vR);
sum += texture2D(uTexture, vT);
sum += texture2D(uTexture, vB);
sum *= 0.25;
gl_FragColor = sum * intensity;
}
`);

const splatShader = compileShader(gl.FRAGMENT_SHADER, `
precision highp float;
precision highp sampler2D;
varying vec2 vUv;
uniform sampler2D uTarget;
uniform float aspectRatio;
uniform vec3 color;
uniform vec2 point;
uniform float radius;
void main () {
vec2 p = vUv - point.xy;
p.x *= aspectRatio;
vec3 splat = exp(-dot(p, p) / radius) * color;
vec3 base = texture2D(uTarget, vUv).xyz;
gl_FragColor = vec4(base + splat, 1.0);
}
`);

const advectionManualFilteringShader = compileShader(gl.FRAGMENT_SHADER, `
precision highp float;
precision highp sampler2D;
varying vec2 vUv;
uniform sampler2D uVelocity;
uniform sampler2D uSource;
uniform vec2 texelSize;
uniform vec2 dyeTexelSize;
uniform float dt;
uniform float dissipation;
vec4 bilerp (sampler2D sam, vec2 uv, vec2 tsize) {
vec2 st = uv / tsize - 0.5;
vec2 iuv = floor(st);
vec2 fuv = fract(st);
vec4 a = texture2D(sam, (iuv + vec2(0.5, 0.5)) * tsize);
vec4 b = texture2D(sam, (iuv + vec2(1.5, 0.5)) * tsize);
vec4 c = texture2D(sam, (iuv + vec2(0.5, 1.5)) * tsize);
vec4 d = texture2D(sam, (iuv + vec2(1.5, 1.5)) * tsize);
return mix(mix(a, b, fuv.x), mix(c, d, fuv.x), fuv.y);
}
void main () {
vec2 coord = vUv - dt * bilerp(uVelocity, vUv, texelSize).xy * texelSize;
gl_FragColor = dissipation * bilerp(uSource, coord, dyeTexelSize);
gl_FragColor.a = 1.0;
}
`);

const advectionShader = compileShader(gl.FRAGMENT_SHADER, `
precision highp float;
precision highp sampler2D;
varying vec2 vUv;
uniform sampler2D uVelocity;
uniform sampler2D uSource;
uniform vec2 texelSize;
uniform float dt;
uniform float dissipation;
void main () {
vec2 coord = vUv - dt * texture2D(uVelocity, vUv).xy * texelSize;
gl_FragColor = dissipation * texture2D(uSource, coord);
gl_FragColor.a = 1.0;
}
`);

const divergenceShader = compileShader(gl.FRAGMENT_SHADER, `
precision mediump float;
precision mediump sampler2D;
varying highp vec2 vUv;
varying highp vec2 vL;
varying highp vec2 vR;
varying highp vec2 vT;
varying highp vec2 vB;
uniform sampler2D uVelocity;
void main () {
float L = texture2D(uVelocity, vL).x;
float R = texture2D(uVelocity, vR).x;
float T = texture2D(uVelocity, vT).y;
float B = texture2D(uVelocity, vB).y;
vec2 C = texture2D(uVelocity, vUv).xy;
if (vL.x < 0.0) { L = -C.x; }
if (vR.x > 1.0) { R = -C.x; }
if (vT.y > 1.0) { T = -C.y; }
if (vB.y < 0.0) { B = -C.y; }
float div = 0.5 * (R - L + T - B);
gl_FragColor = vec4(div, 0.0, 0.0, 1.0);
}
`);

const curlShader = compileShader(gl.FRAGMENT_SHADER, `
precision mediump float;
precision mediump sampler2D;
varying highp vec2 vUv;
varying highp vec2 vL;
varying highp vec2 vR;
varying highp vec2 vT;
varying highp vec2 vB;
uniform sampler2D uVelocity;
void main () {
float L = texture2D(uVelocity, vL).y;
float R = texture2D(uVelocity, vR).y;
float T = texture2D(uVelocity, vT).x;
float B = texture2D(uVelocity, vB).x;
float vorticity = R - L - T + B;
gl_FragColor = vec4(0.5 * vorticity, 0.0, 0.0, 1.0);
}
`);

const vorticityShader = compileShader(gl.FRAGMENT_SHADER, `
precision highp float;
precision highp sampler2D;
varying vec2 vUv;
varying vec2 vL;
varying vec2 vR;
varying vec2 vT;
varying vec2 vB;
uniform sampler2D uVelocity;
uniform sampler2D uCurl;
uniform float curl;
uniform float dt;
void main () {
float L = texture2D(uCurl, vL).x;
float R = texture2D(uCurl, vR).x;
float T = texture2D(uCurl, vT).x;
float B = texture2D(uCurl, vB).x;
float C = texture2D(uCurl, vUv).x;
vec2 force = 0.5 * vec2(abs(T) - abs(B), abs(R) - abs(L));
force /= length(force) + 0.0001;
force *= curl * C;
force.y *= -1.0;
vec2 vel = texture2D(uVelocity, vUv).xy;
gl_FragColor = vec4(vel + force * dt, 0.0, 1.0);
}
`);

const pressureShader = compileShader(gl.FRAGMENT_SHADER, `
precision mediump float;
precision mediump sampler2D;
varying highp vec2 vUv;
varying highp vec2 vL;
varying highp vec2 vR;
varying highp vec2 vT;
varying highp vec2 vB;
uniform sampler2D uPressure;
uniform sampler2D uDivergence;
vec2 boundary (vec2 uv) {
return uv;
// uncomment if you use wrap or repeat texture mode// uv = min(max(uv, 0.0), 1.0);// return uv;
}
void main () {
float L = texture2D(uPressure, boundary(vL)).x;
float R = texture2D(uPressure, boundary(vR)).x;
float T = texture2D(uPressure, boundary(vT)).x;
float B = texture2D(uPressure, boundary(vB)).x;
float C = texture2D(uPressure, vUv).x;
float divergence = texture2D(uDivergence, vUv).x;
float pressure = (L + R + B + T - divergence) * 0.25;
gl_FragColor = vec4(pressure, 0.0, 0.0, 1.0);
}
`);

const gradientSubtractShader = compileShader(gl.FRAGMENT_SHADER, `
precision mediump float;
precision mediump sampler2D;
varying highp vec2 vUv;
varying highp vec2 vL;
varying highp vec2 vR;
varying highp vec2 vT;
varying highp vec2 vB;
uniform sampler2D uPressure;
uniform sampler2D uVelocity;
vec2 boundary (vec2 uv) {
return uv;
// uv = min(max(uv, 0.0), 1.0);// return uv;
}
void main () {
float L = texture2D(uPressure, boundary(vL)).x;
float R = texture2D(uPressure, boundary(vR)).x;
float T = texture2D(uPressure, boundary(vT)).x;
float B = texture2D(uPressure, boundary(vB)).x;
vec2 velocity = texture2D(uVelocity, vUv).xy;
velocity.xy -= vec2(R - L, T - B);
gl_FragColor = vec4(velocity, 0.0, 1.0);
}
`);

const blit = (() => {
gl.bindBuffer(gl.ARRAY_BUFFER, gl.createBuffer());
gl.bufferData(gl.ARRAY_BUFFER, new Float32Array([-1, -1, -1, 1, 1, 1, 1, -1]), gl.STATIC_DRAW);
gl.bindBuffer(gl.ELEMENT_ARRAY_BUFFER, gl.createBuffer());
gl.bufferData(gl.ELEMENT_ARRAY_BUFFER, new Uint16Array([0, 1, 2, 0, 2, 3]), gl.STATIC_DRAW);
gl.vertexAttribPointer(0, 2, gl.FLOAT, false, 0, 0);
gl.enableVertexAttribArray(0);

return (destination) => {
gl.bindFramebuffer(gl.FRAMEBUFFER, destination);
gl.drawElements(gl.TRIANGLES, 6, gl.UNSIGNED_SHORT, 0);
}
})();

let simWidth;
let simHeight;
let dyeWidth;
let dyeHeight;
let density;
let velocity;
let divergence;
let curl;
let pressure;
let bloom;

let ditheringTexture = createTextureAsync('LDR_RGB1_0.png');

const clearProgram = new GLProgram(baseVertexShader, clearShader);
const colorProgram = new GLProgram(baseVertexShader, colorShader);
const backgroundProgram = new GLProgram(baseVertexShader, backgroundShader);
const displayProgram = new GLProgram(baseVertexShader, displayShader);
const displayBloomProgram = new GLProgram(baseVertexShader, displayBloomShader);
const displayShadingProgram = new GLProgram(baseVertexShader, displayShadingShader);
const displayBloomShadingProgram = new GLProgram(baseVertexShader, displayBloomShadingShader);
const bloomPrefilterProgram = new GLProgram(baseVertexShader, bloomPrefilterShader);
const bloomBlurProgram = new GLProgram(baseVertexShader, bloomBlurShader);
const bloomFinalProgram = new GLProgram(baseVertexShader, bloomFinalShader);
const splatProgram = new GLProgram(baseVertexShader, splatShader);
const advectionProgram = new GLProgram(baseVertexShader, ext.supportLinearFiltering ? advectionShader : advectionManualFilteringShader);
const divergenceProgram = new GLProgram(baseVertexShader, divergenceShader);
const curlProgram = new GLProgram(baseVertexShader, curlShader);
const vorticityProgram = new GLProgram(baseVertexShader, vorticityShader);
const pressureProgram = new GLProgram(baseVertexShader, pressureShader);
const gradienSubtractProgram = new GLProgram(baseVertexShader, gradientSubtractShader);

function initFramebuffers () {
let simRes = getResolution(config.SIM_RESOLUTION);
let dyeRes = getResolution(config.DYE_RESOLUTION);

simWidth = simRes.width;
simHeight = simRes.height;
dyeWidth = dyeRes.width;
dyeHeight = dyeRes.height;

const texType = ext.halfFloatTexType;
const rgba = ext.formatRGBA;
const rg = ext.formatRG;
const r = ext.formatR;
const filtering = ext.supportLinearFiltering ? gl.LINEAR : gl.NEAREST;

if (density == null)
density = createDoubleFBO(dyeWidth, dyeHeight, rgba.internalFormat, rgba.format, texType, filtering);
else
density = resizeDoubleFBO(density, dyeWidth, dyeHeight, rgba.internalFormat, rgba.format, texType, filtering);

if (velocity == null)
velocity = createDoubleFBO(simWidth, simHeight, rg.internalFormat, rg.format, texType, filtering);
else
velocity = resizeDoubleFBO(velocity, simWidth, simHeight, rg.internalFormat, rg.format, texType, filtering);

divergence = createFBO (simWidth, simHeight, r.internalFormat, r.format, texType, gl.NEAREST);
curl = createFBO (simWidth, simHeight, r.internalFormat, r.format, texType, gl.NEAREST);
pressure = createDoubleFBO(simWidth, simHeight, r.internalFormat, r.format, texType, gl.NEAREST);

initBloomFramebuffers();
}

function initBloomFramebuffers () {
let res = getResolution(config.BLOOM_RESOLUTION);

const texType = ext.halfFloatTexType;
const rgba = ext.formatRGBA;
const filtering = ext.supportLinearFiltering ? gl.LINEAR : gl.NEAREST;

bloom = createFBO(res.width, res.height, rgba.internalFormat, rgba.format, texType, filtering);

bloomFramebuffers.length = 0;
for (let i = 0; i < config.BLOOM_ITERATIONS; i++)
{
let width = res.width >> (i + 1);
let height = res.height >> (i + 1);

if (width < 2 || height < 2) break;

let fbo = createFBO(width, height, rgba.internalFormat, rgba.format, texType, filtering);
bloomFramebuffers.push(fbo);
}
}

function createFBO (w, h, internalFormat, format, type, param) {
gl.activeTexture(gl.TEXTURE0);
let texture = gl.createTexture();
gl.bindTexture(gl.TEXTURE_2D, texture);
gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, param);
gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, param);
gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_S, gl.CLAMP_TO_EDGE);
gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_T, gl.CLAMP_TO_EDGE);
gl.texImage2D(gl.TEXTURE_2D, 0, internalFormat, w, h, 0, format, type, null);

let fbo = gl.createFramebuffer();
gl.bindFramebuffer(gl.FRAMEBUFFER, fbo);
gl.framebufferTexture2D(gl.FRAMEBUFFER, gl.COLOR_ATTACHMENT0, gl.TEXTURE_2D, texture, 0);
gl.viewport(0, 0, w, h);
gl.clear(gl.COLOR_BUFFER_BIT);

return {
texture,
fbo,
width: w,
height: h,
attach (id) {
gl.activeTexture(gl.TEXTURE0 + id);
gl.bindTexture(gl.TEXTURE_2D, texture);
return id;
}
};
}

function createDoubleFBO (w, h, internalFormat, format, type, param) {
let fbo1 = createFBO(w, h, internalFormat, format, type, param);
let fbo2 = createFBO(w, h, internalFormat, format, type, param);

return {
get read () {
return fbo1;
},
set read (value) {
fbo1 = value;
},
get write () {
return fbo2;
},
set write (value) {
fbo2 = value;
},
swap () {
let temp = fbo1;
fbo1 = fbo2;
fbo2 = temp;
}
}
}

function resizeFBO (target, w, h, internalFormat, format, type, param) {
let newFBO = createFBO(w, h, internalFormat, format, type, param);
clearProgram.bind();
gl.uniform1i(clearProgram.uniforms.uTexture, target.attach(0));
gl.uniform1f(clearProgram.uniforms.value, 1);
blit(newFBO.fbo);
return newFBO;
}

function resizeDoubleFBO (target, w, h, internalFormat, format, type, param) {
target.read = resizeFBO(target.read, w, h, internalFormat, format, type, param);
target.write = createFBO(w, h, internalFormat, format, type, param);
return target;
}

function createTextureAsync (url) {
let texture = gl.createTexture();
gl.bindTexture(gl.TEXTURE_2D, texture);
gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, gl.LINEAR);
gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, gl.LINEAR);
gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_S, gl.REPEAT);
gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_T, gl.REPEAT);
gl.texImage2D(gl.TEXTURE_2D, 0, gl.RGB, 1, 1, 0, gl.RGB, gl.UNSIGNED_BYTE, new Uint8Array([255, 255, 255]));

let obj = {
texture,
width: 1,
height: 1,
attach (id) {
gl.activeTexture(gl.TEXTURE0 + id);
gl.bindTexture(gl.TEXTURE_2D, texture);
return id;
}
};

let image = new Image();
image.onload = () => {
obj.width = image.width;
obj.height = image.height;
gl.bindTexture(gl.TEXTURE_2D, texture);
gl.texImage2D(gl.TEXTURE_2D, 0, gl.RGB, gl.RGB, gl.UNSIGNED_BYTE, image);
};
image.src = url;

return obj;
}

initFramebuffers();
multipleSplats(parseInt(Math.random() * 20) + 5);

let lastColorChangeTime = Date.now();

update();

function update () {
resizeCanvas();
input();
if (!config.PAUSED)
step(0.016);
render(null);
requestAnimationFrame(update);
}

function input () {
if (splatStack.length > 0)
multipleSplats(splatStack.pop());

for (let i = 0; i < pointers.length; i++) {
const p = pointers[i];
if (p.moved) {
splat(p.x, p.y, p.dx, p.dy, p.color);
p.moved = false;
}
}

if (!config.COLORFUL)
return;

if (lastColorChangeTime + 100 < Date.now())
{
lastColorChangeTime = Date.now();
for (let i = 0; i < pointers.length; i++) {
const p = pointers[i];
p.color = generateColor();
}
}
}

function step (dt) {
gl.disable(gl.BLEND);
gl.viewport(0, 0, simWidth, simHeight);

curlProgram.bind();
gl.uniform2f(curlProgram.uniforms.texelSize, 1.0 / simWidth, 1.0 / simHeight);
gl.uniform1i(curlProgram.uniforms.uVelocity, velocity.read.attach(0));
blit(curl.fbo);

vorticityProgram.bind();
gl.uniform2f(vorticityProgram.uniforms.texelSize, 1.0 / simWidth, 1.0 / simHeight);
gl.uniform1i(vorticityProgram.uniforms.uVelocity, velocity.read.attach(0));
gl.uniform1i(vorticityProgram.uniforms.uCurl, curl.attach(1));
gl.uniform1f(vorticityProgram.uniforms.curl, config.CURL);
gl.uniform1f(vorticityProgram.uniforms.dt, dt);
blit(velocity.write.fbo);
velocity.swap();

divergenceProgram.bind();
gl.uniform2f(divergenceProgram.uniforms.texelSize, 1.0 / simWidth, 1.0 / simHeight);
gl.uniform1i(divergenceProgram.uniforms.uVelocity, velocity.read.attach(0));
blit(divergence.fbo);

clearProgram.bind();
gl.uniform1i(clearProgram.uniforms.uTexture, pressure.read.attach(0));
gl.uniform1f(clearProgram.uniforms.value, config.PRESSURE_DISSIPATION);
blit(pressure.write.fbo);
pressure.swap();

pressureProgram.bind();
gl.uniform2f(pressureProgram.uniforms.texelSize, 1.0 / simWidth, 1.0 / simHeight);
gl.uniform1i(pressureProgram.uniforms.uDivergence, divergence.attach(0));
for (let i = 0; i < config.PRESSURE_ITERATIONS; i++) {
gl.uniform1i(pressureProgram.uniforms.uPressure, pressure.read.attach(1));
blit(pressure.write.fbo);
pressure.swap();
}

gradienSubtractProgram.bind();
gl.uniform2f(gradienSubtractProgram.uniforms.texelSize, 1.0 / simWidth, 1.0 / simHeight);
gl.uniform1i(gradienSubtractProgram.uniforms.uPressure, pressure.read.attach(0));
gl.uniform1i(gradienSubtractProgram.uniforms.uVelocity, velocity.read.attach(1));
blit(velocity.write.fbo);
velocity.swap();

advectionProgram.bind();
gl.uniform2f(advectionProgram.uniforms.texelSize, 1.0 / simWidth, 1.0 / simHeight);
if (!ext.supportLinearFiltering)
gl.uniform2f(advectionProgram.uniforms.dyeTexelSize, 1.0 / simWidth, 1.0 / simHeight);
let velocityId = velocity.read.attach(0);
gl.uniform1i(advectionProgram.uniforms.uVelocity, velocityId);
gl.uniform1i(advectionProgram.uniforms.uSource, velocityId);
gl.uniform1f(advectionProgram.uniforms.dt, dt);
gl.uniform1f(advectionProgram.uniforms.dissipation, config.VELOCITY_DISSIPATION);
blit(velocity.write.fbo);
velocity.swap();

gl.viewport(0, 0, dyeWidth, dyeHeight);

if (!ext.supportLinearFiltering)
gl.uniform2f(advectionProgram.uniforms.dyeTexelSize, 1.0 / dyeWidth, 1.0 / dyeHeight);
gl.uniform1i(advectionProgram.uniforms.uVelocity, velocity.read.attach(0));
gl.uniform1i(advectionProgram.uniforms.uSource, density.read.attach(1));
gl.uniform1f(advectionProgram.uniforms.dissipation, config.DENSITY_DISSIPATION);
blit(density.write.fbo);
density.swap();
}

function render (target) {
if (config.BLOOM)
applyBloom(density.read, bloom);

if (target == null || !config.TRANSPARENT) {
gl.blendFunc(gl.ONE, gl.ONE_MINUS_SRC_ALPHA);
gl.enable(gl.BLEND);
}
else {
gl.disable(gl.BLEND);
}

let width = target == null ? gl.drawingBufferWidth : dyeWidth;
let height = target == null ? gl.drawingBufferHeight : dyeHeight;

gl.viewport(0, 0, width, height);

if (!config.TRANSPARENT) {
colorProgram.bind();
let bc = config.BACK_COLOR;
gl.uniform4f(colorProgram.uniforms.color, bc.r / 255, bc.g / 255, bc.b / 255, 1);
blit(target);
}

if (target == null && config.TRANSPARENT) {
backgroundProgram.bind();
gl.uniform1f(backgroundProgram.uniforms.aspectRatio, canvas.width / canvas.height);
blit(null);
}

if (config.SHADING) {
let program = config.BLOOM ? displayBloomShadingProgram : displayShadingProgram;
program.bind();
gl.uniform2f(program.uniforms.texelSize, 1.0 / width, 1.0 / height);
gl.uniform1i(program.uniforms.uTexture, density.read.attach(0));
if (config.BLOOM) {
gl.uniform1i(program.uniforms.uBloom, bloom.attach(1));
gl.uniform1i(program.uniforms.uDithering, ditheringTexture.attach(2));
let scale = getTextureScale(ditheringTexture, width, height);
gl.uniform2f(program.uniforms.ditherScale, scale.x, scale.y);
}
}
else {
let program = config.BLOOM ? displayBloomProgram : displayProgram;
program.bind();
gl.uniform1i(program.uniforms.uTexture, density.read.attach(0));
if (config.BLOOM) {
gl.uniform1i(program.uniforms.uBloom, bloom.attach(1));
gl.uniform1i(program.uniforms.uDithering, ditheringTexture.attach(2));
let scale = getTextureScale(ditheringTexture, width, height);
gl.uniform2f(program.uniforms.ditherScale, scale.x, scale.y);
}
}

blit(target);
}

function applyBloom (source, destination) {
if (bloomFramebuffers.length < 2)
return;

let last = destination;

gl.disable(gl.BLEND);
bloomPrefilterProgram.bind();
let knee = config.BLOOM_THRESHOLD * config.BLOOM_SOFT_KNEE + 0.0001;
let curve0 = config.BLOOM_THRESHOLD - knee;
let curve1 = knee * 2;
let curve2 = 0.25 / knee;
gl.uniform3f(bloomPrefilterProgram.uniforms.curve, curve0, curve1, curve2);
gl.uniform1f(bloomPrefilterProgram.uniforms.threshold, config.BLOOM_THRESHOLD);
gl.uniform1i(bloomPrefilterProgram.uniforms.uTexture, source.attach(0));
gl.viewport(0, 0, last.width, last.height);
blit(last.fbo);

bloomBlurProgram.bind();
for (let i = 0; i < bloomFramebuffers.length; i++) {
let dest = bloomFramebuffers[i];
gl.uniform2f(bloomBlurProgram.uniforms.texelSize, 1.0 / last.width, 1.0 / last.height);
gl.uniform1i(bloomBlurProgram.uniforms.uTexture, last.attach(0));
gl.viewport(0, 0, dest.width, dest.height);
blit(dest.fbo);
last = dest;
}

gl.blendFunc(gl.ONE, gl.ONE);
gl.enable(gl.BLEND);

for (let i = bloomFramebuffers.length - 2; i >= 0; i--) {
let baseTex = bloomFramebuffers[i];
gl.uniform2f(bloomBlurProgram.uniforms.texelSize, 1.0 / last.width, 1.0 / last.height);
gl.uniform1i(bloomBlurProgram.uniforms.uTexture, last.attach(0));
gl.viewport(0, 0, baseTex.width, baseTex.height);
blit(baseTex.fbo);
last = baseTex;
}

gl.disable(gl.BLEND);
bloomFinalProgram.bind();
gl.uniform2f(bloomFinalProgram.uniforms.texelSize, 1.0 / last.width, 1.0 / last.height);
gl.uniform1i(bloomFinalProgram.uniforms.uTexture, last.attach(0));
gl.uniform1f(bloomFinalProgram.uniforms.intensity, config.BLOOM_INTENSITY);
gl.viewport(0, 0, destination.width, destination.height);
blit(destination.fbo);
}

function splat (x, y, dx, dy, color) {
gl.viewport(0, 0, simWidth, simHeight);
splatProgram.bind();
gl.uniform1i(splatProgram.uniforms.uTarget, velocity.read.attach(0));
gl.uniform1f(splatProgram.uniforms.aspectRatio, canvas.width / canvas.height);
gl.uniform2f(splatProgram.uniforms.point, x / canvas.width, 1.0 - y / canvas.height);
gl.uniform3f(splatProgram.uniforms.color, dx, -dy, 1.0);
gl.uniform1f(splatProgram.uniforms.radius, config.SPLAT_RADIUS / 100.0);
blit(velocity.write.fbo);
velocity.swap();

gl.viewport(0, 0, dyeWidth, dyeHeight);
gl.uniform1i(splatProgram.uniforms.uTarget, density.read.attach(0));
gl.uniform3f(splatProgram.uniforms.color, color.r, color.g, color.b);
blit(density.write.fbo);
density.swap();
}

function multipleSplats (amount) {
for (let i = 0; i < amount; i++) {
const color = generateColor();
color.r *= 10.0;
color.g *= 10.0;
color.b *= 10.0;
const x = canvas.width * Math.random();
const y = canvas.height * Math.random();
const dx = 1000 * (Math.random() - 0.5);
const dy = 1000 * (Math.random() - 0.5);
splat(x, y, dx, dy, color);
}
}

function resizeCanvas () {
if (canvas.width != canvas.clientWidth || canvas.height != canvas.clientHeight) {
canvas.width = canvas.clientWidth;
canvas.height = canvas.clientHeight;
initFramebuffers();
}
}

canvas.addEventListener('mousemove', e => {
pointers[0].moved = pointers[0].down;
pointers[0].dx = (e.offsetX - pointers[0].x) * 5.0;
pointers[0].dy = (e.offsetY - pointers[0].y) * 5.0;
pointers[0].x = e.offsetX;
pointers[0].y = e.offsetY;
});

canvas.addEventListener('touchmove', e => {
e.preventDefault();
const touches = e.targetTouches;
for (let i = 0; i < touches.length; i++) {
let pointer = pointers[i];
pointer.moved = pointer.down;
pointer.dx = (touches[i].pageX - pointer.x) * 8.0;
pointer.dy = (touches[i].pageY - pointer.y) * 8.0;
pointer.x = touches[i].pageX;
pointer.y = touches[i].pageY;
}
}, false);

canvas.addEventListener('mousedown', () => {
pointers[0].down = true;
pointers[0].color = generateColor();
});

canvas.addEventListener('touchstart', e => {
e.preventDefault();
const touches = e.targetTouches;
for (let i = 0; i < touches.length; i++) {
if (i >= pointers.length)
pointers.push(new pointerPrototype());

pointers[i].id = touches[i].identifier;
pointers[i].down = true;
pointers[i].x = touches[i].pageX;
pointers[i].y = touches[i].pageY;
pointers[i].color = generateColor();
}
});

window.addEventListener('mouseup', () => {
pointers[0].down = false;
});

window.addEventListener('touchend', e => {
const touches = e.changedTouches;
for (let i = 0; i < touches.length; i++)
for (let j = 0; j < pointers.length; j++)
if (touches[i].identifier == pointers[j].id)
pointers[j].down = false;
});

window.addEventListener('keydown', e => {
if (e.code === 'KeyP')
config.PAUSED = !config.PAUSED;
if (e.key === ' ')
splatStack.push(parseInt(Math.random() * 20) + 5);
});

function generateColor () {
let c = HSVtoRGB(Math.random(), 1.0, 1.0);
c.r *= 0.15;
c.g *= 0.15;
c.b *= 0.15;
return c;
}

function HSVtoRGB (h, s, v) {
let r, g, b, i, f, p, q, t;
i = Math.floor(h * 6);
f = h * 6 - i;
p = v * (1 - s);
q = v * (1 - f * s);
t = v * (1 - (1 - f) * s);

switch (i % 6) {
case 0: r = v, g = t, b = p; break;
case 1: r = q, g = v, b = p; break;
case 2: r = p, g = v, b = t; break;
case 3: r = p, g = q, b = v; break;
case 4: r = t, g = p, b = v; break;
case 5: r = v, g = p, b = q; break;
}

return {
r,
g,
b
};
}

function getResolution (resolution) {
let aspectRatio = gl.drawingBufferWidth / gl.drawingBufferHeight;
if (aspectRatio < 1)
aspectRatio = 1.0 / aspectRatio;

let max = Math.round(resolution * aspectRatio);
let min = Math.round(resolution);

if (gl.drawingBufferWidth > gl.drawingBufferHeight)
return { width: max, height: min };
elsereturn { width: min, height: max };
}

function getTextureScale (texture, width, height) {
return {
x: width / texture.width,
y: height / texture.height
};
}
</script>

<script>
$(".tn-elem__1196630671564745363991 .tn-atom").append("<canvas id='particle-canvas'></canvas>");
</script>
<style>
#particle-canvas {
background: linear-gradient(to bottom, rgb(10, 10, 50) 0%,rgb(60, 10, 60) 100%);
vertical-align: middle;
width: 100%;
height: 100vh;
}
</style>
<script>// modified version of random-normal
function normalPool(o){var r=0;do{var a=Math.round(normal({mean:o.mean,dev:o.dev}));if(a<o.pool.length&&a>=0)return o.pool[a];r++}while(r<100)}function randomNormal(o){if(o=Object.assign({mean:0,dev:1,pool:[]},o),Array.isArray(o.pool)&&o.pool.length>0)return normalPool(o);var r,a,n,e,l=o.mean,t=o.dev;do{r=(a=2*Math.random()-1)*a+(n=2*Math.random()-1)*n}while(r>=1);return e=a*Math.sqrt(-2*Math.log(r)/r),t*e+l}

const NUM_PARTICLES = 600;
const PARTICLE_SIZE = 0.5; // View heights
const SPEED = 20000; // Milliseconds

let particles = [];

function rand(low, high) {
return Math.random() * (high - low) + low;
}

function createParticle(canvas) {
const colour = {
r: 255,
g: randomNormal({ mean: 125, dev: 20 }),
b: 50,
a: rand(0, 1),
};
return {
x: -2,
y: -2,
diameter: Math.max(0, randomNormal({ mean: PARTICLE_SIZE, dev: PARTICLE_SIZE / 2 })),
duration: randomNormal({ mean: SPEED, dev: SPEED * 0.1 }),
amplitude: randomNormal({ mean: 16, dev: 2 }),
offsetY: randomNormal({ mean: 0, dev: 10 }),
arc: Math.PI * 2,
startTime: performance.now() - rand(0, SPEED),
colour: `rgba(${colour.r}, ${colour.g}, ${colour.b}, ${colour.a})`,
}
}

function moveParticle(particle, canvas, time) {
const progress = ((time - particle.startTime) % particle.duration) / particle.duration;
return {
...particle,
x: progress,
y: ((Math.sin(progress * particle.arc) * particle.amplitude) + particle.offsetY),
};
}

function drawParticle(particle, canvas, ctx) {
canvas = document.getElementById('particle-canvas');
const vh = canvas.height / 100;

ctx.fillStyle = particle.colour;
ctx.beginPath();
ctx.ellipse(
particle.x * canvas.width,
particle.y * vh + (canvas.height / 2),
particle.diameter * vh,
particle.diameter * vh,
0,
0,
2 * Math.PI
);
ctx.fill();
}

function draw(time, canvas, ctx) {
// Move particles
particles.forEach((particle, index) => {
particles[index] = moveParticle(particle, canvas, time);
})

// Clear the canvas
ctx.clearRect(0, 0, canvas.width, canvas.height);

// Draw the particles
particles.forEach((particle) => {
drawParticle(particle, canvas, ctx);
})

// Schedule next frame
requestAnimationFrame((time) => draw(time, canvas, ctx));
}

function initializeCanvas() {
let canvas = document.getElementById('particle-canvas');
canvas.width = canvas.offsetWidth * window.devicePixelRatio;
canvas.height = canvas.offsetHeight * window.devicePixelRatio;
let ctx = canvas.getContext("2d");

window.addEventListener('resize', () => {
canvas.width = canvas.offsetWidth * window.devicePixelRatio;
canvas.height = canvas.offsetHeight * window.devicePixelRatio;
ctx = canvas.getContext("2d");
})

return [canvas, ctx];
}

function startAnimation() {
const [canvas, ctx] = initializeCanvas();

// Create a bunch of particlesfor (let i = 0; i < NUM_PARTICLES; i++) {
particles.push(createParticle(canvas));
}

requestAnimationFrame((time) => draw(time, canvas, ctx));
};

// Start animation when document is loaded
(function () {
if (document.readystate !== 'loading') {
startAnimation();
} else {
document.addEventListener('DOMContentLoaded', () => {
startAnimation();
})
}
}());

</script>