function initSplashCursor(userConfig = {}) {
  // Configuração padrão fundida com as opções do usuário
  let config = {
    SIM_RESOLUTION: 128,
    DYE_RESOLUTION: 1440,
    CAPTURE_RESOLUTION: 512,
    DENSITY_DISSIPATION: 10,
    VELOCITY_DISSIPATION: 10,
    PRESSURE: 0,
    PRESSURE_ITERATIONS: 20,
    CURL: 0,
    SPLAT_RADIUS: 0.09,
    SPLAT_FORCE: 1000,
    SHADING: false,
    COLOR_UPDATE_SPEED: 1,
    PAUSED: false,
    BACK_COLOR: { r: 0.5, g: 0, b: 0 },
    TRANSPARENT: true,
    RAINBOW_MODE: false,
    COLOR: '#a855f7',
    ...userConfig
  };

  // Criação do HTML correspondente dinamicamente
  let container = document.getElementById('splash-cursor-container');
  let canvas = document.getElementById('fluid');

  if (!container) {
    container = document.createElement('div');
    container.id = 'splash-cursor-container';
    container.style.position = 'fixed';
    container.style.top = '0';
    container.style.left = '0';
    // Opcional: ajustar z-index conforme o layout. 50 ou 9999
    container.style.zIndex = '50';
    container.style.pointerEvents = 'none';
    container.style.width = '100%';
    container.style.height = '100%';
    document.body.appendChild(container);

    canvas = document.createElement('canvas');
    canvas.id = 'fluid';
    canvas.style.width = '100vw';
    canvas.style.height = '100vh';
    canvas.style.display = 'block';
    canvas.style.pointerEvents = 'none';
    container.appendChild(canvas);
  }

  if (!canvas) return null;

  let isActive = true;
  let animationFrameId = null;

  function pointerPrototype() {
    this.id = -1;
    this.texcoordX = 0;
    this.texcoordY = 0;
    this.prevTexcoordX = 0;
    this.prevTexcoordY = 0;
    this.deltaX = 0;
    this.deltaY = 0;
    this.down = false;
    this.moved = false;
    this.color = [0, 0, 0];
  }

  let pointers = [new pointerPrototype()];

  const { gl, ext } = getWebGLContext(canvas);
  if (!ext.supportLinearFiltering) {
    config.DYE_RESOLUTION = 256;
    config.SHADING = 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 && 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) {
    const 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);
    const 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);
    return status === gl.FRAMEBUFFER_COMPLETE;
  }

  class Material {
    constructor(vertexShader, fragmentShaderSource) {
      this.vertexShader = vertexShader;
      this.fragmentShaderSource = fragmentShaderSource;
      this.programs = [];
      this.activeProgram = null;
      this.uniforms = [];
    }
    setKeywords(keywords) {
      let hash = 0;
      for (let i = 0; i < keywords.length; i++) hash += hashCode(keywords[i]);
      let program = this.programs[hash];
      if (program == null) {
        let fragmentShader = compileShader(gl.FRAGMENT_SHADER, this.fragmentShaderSource, keywords);
        program = createProgram(this.vertexShader, fragmentShader);
        this.programs[hash] = program;
      }
      if (program === this.activeProgram) return;
      this.uniforms = getUniforms(program);
      this.activeProgram = program;
    }
    bind() {
      gl.useProgram(this.activeProgram);
    }
  }

  class Program {
    constructor(vertexShader, fragmentShader) {
      this.uniforms = {};
      this.program = createProgram(vertexShader, fragmentShader);
      this.uniforms = getUniforms(this.program);
    }
    bind() {
      gl.useProgram(this.program);
    }
  }

  function createProgram(vertexShader, fragmentShader) {
    let program = gl.createProgram();
    gl.attachShader(program, vertexShader);
    gl.attachShader(program, fragmentShader);
    gl.linkProgram(program);
    if (!gl.getProgramParameter(program, gl.LINK_STATUS)) console.trace(gl.getProgramInfoLog(program));
    return program;
  }

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

  function compileShader(type, source, keywords) {
    source = addKeywords(source, keywords);
    const shader = gl.createShader(type);
    gl.shaderSource(shader, source);
    gl.compileShader(shader);
    if (!gl.getShaderParameter(shader, gl.COMPILE_STATUS)) console.trace(gl.getShaderInfoLog(shader));
    return shader;
  }

  function addKeywords(source, keywords) {
    if (!keywords) return source;
    let keywordsString = '';
    keywords.forEach(keyword => {
      keywordsString += '#define ' + keyword + '\n';
    });
    return keywordsString + source;
  }

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

  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 displayShaderSource = `
    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 uDithering;
    uniform vec2 ditherScale;
    uniform vec2 texelSize;

    vec3 linearToGamma (vec3 color) {
        color = max(color, vec3(0));
        return max(1.055 * pow(color, vec3(0.416666667)) - 0.055, vec3(0));
    }

    void main () {
        vec3 c = texture2D(uTexture, vUv).rgb;
        #ifdef SHADING
            vec3 lc = texture2D(uTexture, vL).rgb;
            vec3 rc = texture2D(uTexture, vR).rgb;
            vec3 tc = texture2D(uTexture, vT).rgb;
            vec3 bc = texture2D(uTexture, vB).rgb;

            float dx = length(rc) - length(lc);
            float dy = length(tc) - length(bc);

            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;
        #endif

        float a = max(c.r, max(c.g, c.b));
        gl_FragColor = vec4(c, a);
    }
  `;

  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 advectionShader = 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 () {
          #ifdef MANUAL_FILTERING
              vec2 coord = vUv - dt * bilerp(uVelocity, vUv, texelSize).xy * texelSize;
              vec4 result = bilerp(uSource, coord, dyeTexelSize);
          #else
              vec2 coord = vUv - dt * texture2D(uVelocity, vUv).xy * texelSize;
              vec4 result = texture2D(uSource, coord);
          #endif
          float decay = 1.0 + dissipation * dt;
          gl_FragColor = result / decay;
      }
  `, ext.supportLinearFiltering ? null : ['MANUAL_FILTERING']);

  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 velocity = texture2D(uVelocity, vUv).xy;
          velocity += force * dt;
          velocity = min(max(velocity, -1000.0), 1000.0);
          gl_FragColor = vec4(velocity, 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;
      void main () {
          float L = texture2D(uPressure, vL).x;
          float R = texture2D(uPressure, vR).x;
          float T = texture2D(uPressure, vT).x;
          float B = texture2D(uPressure, 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;
      void main () {
          float L = texture2D(uPressure, vL).x;
          float R = texture2D(uPressure, vR).x;
          float T = texture2D(uPressure, vT).x;
          float B = texture2D(uPressure, 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 (target, clear = false) => {
      if (target == null) {
        gl.viewport(0, 0, gl.drawingBufferWidth, gl.drawingBufferHeight);
        gl.bindFramebuffer(gl.FRAMEBUFFER, null);
      } else {
        gl.viewport(0, 0, target.width, target.height);
        gl.bindFramebuffer(gl.FRAMEBUFFER, target.fbo);
      }
      if (clear) {
        gl.clearColor(0.0, 0.0, 0.0, 1.0);
        gl.clear(gl.COLOR_BUFFER_BIT);
      }
      gl.drawElements(gl.TRIANGLES, 6, gl.UNSIGNED_SHORT, 0);
    };
  })();

  let dye, velocity, divergence, curl, pressure;

  const copyProgram = new Program(baseVertexShader, copyShader);
  const clearProgram = new Program(baseVertexShader, clearShader);
  const splatProgram = new Program(baseVertexShader, splatShader);
  const advectionProgram = new Program(baseVertexShader, advectionShader);
  const divergenceProgram = new Program(baseVertexShader, divergenceShader);
  const curlProgram = new Program(baseVertexShader, curlShader);
  const vorticityProgram = new Program(baseVertexShader, vorticityShader);
  const pressureProgram = new Program(baseVertexShader, pressureShader);
  const gradienSubtractProgram = new Program(baseVertexShader, gradientSubtractShader);
  const displayMaterial = new Material(baseVertexShader, displayShaderSource);

  function initFramebuffers() {
    let simRes = getResolution(config.SIM_RESOLUTION);
    let dyeRes = getResolution(config.DYE_RESOLUTION);
    const texType = ext.halfFloatTexType;
    const rgba = ext.formatRGBA;
    const rg = ext.formatRG;
    const r = ext.formatR;
    const filtering = ext.supportLinearFiltering ? gl.LINEAR : gl.NEAREST;
    gl.disable(gl.BLEND);

    if (!dye)
      dye = createDoubleFBO(dyeRes.width, dyeRes.height, rgba.internalFormat, rgba.format, texType, filtering);
    else
      dye = resizeDoubleFBO(dye, dyeRes.width, dyeRes.height, rgba.internalFormat, rgba.format, texType, filtering);

    if (!velocity)
      velocity = createDoubleFBO(simRes.width, simRes.height, rg.internalFormat, rg.format, texType, filtering);
    else
      velocity = resizeDoubleFBO(velocity, simRes.width, simRes.height, rg.internalFormat, rg.format, texType, filtering);

    divergence = createFBO(simRes.width, simRes.height, r.internalFormat, r.format, texType, gl.NEAREST);
    curl = createFBO(simRes.width, simRes.height, r.internalFormat, r.format, texType, gl.NEAREST);
    pressure = createDoubleFBO(simRes.width, simRes.height, r.internalFormat, r.format, texType, gl.NEAREST);
  }

  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);

    let texelSizeX = 1.0 / w;
    let texelSizeY = 1.0 / h;
    return {
      texture,
      fbo,
      width: w,
      height: h,
      texelSizeX,
      texelSizeY,
      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 {
      width: w,
      height: h,
      texelSizeX: fbo1.texelSizeX,
      texelSizeY: fbo1.texelSizeY,
      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);
    copyProgram.bind();
    gl.uniform1i(copyProgram.uniforms.uTexture, target.attach(0));
    blit(newFBO);
    return newFBO;
  }

  function resizeDoubleFBO(target, w, h, internalFormat, format, type, param) {
    if (target.width === w && target.height === h) return target;
    target.read = resizeFBO(target.read, w, h, internalFormat, format, type, param);
    target.write = createFBO(w, h, internalFormat, format, type, param);
    target.width = w;
    target.height = h;
    target.texelSizeX = 1.0 / w;
    target.texelSizeY = 1.0 / h;
    return target;
  }

  function updateKeywords() {
    let displayKeywords = [];
    if (config.SHADING) displayKeywords.push('SHADING');
    displayMaterial.setKeywords(displayKeywords);
  }

  updateKeywords();
  initFramebuffers();
  let lastUpdateTime = Date.now();
  let colorUpdateTimer = 0.0;

  function updateFrame() {
    if (!isActive) return;
    const dt = calcDeltaTime();
    if (resizeCanvas()) initFramebuffers();
    updateColors(dt);
    applyInputs();
    step(dt);
    render(null);
    animationFrameId = requestAnimationFrame(updateFrame);
  }

  function calcDeltaTime() {
    let now = Date.now();
    let dt = (now - lastUpdateTime) / 1000;
    dt = Math.min(dt, 0.016666);
    lastUpdateTime = now;
    return dt;
  }

  function resizeCanvas() {
    let width = scaleByPixelRatio(canvas.clientWidth);
    let height = scaleByPixelRatio(canvas.clientHeight);
    if (canvas.width !== width || canvas.height !== height) {
      canvas.width = width;
      canvas.height = height;
      return true;
    }
    return false;
  }

  function updateColors(dt) {
    colorUpdateTimer += dt * config.COLOR_UPDATE_SPEED;
    if (colorUpdateTimer >= 1) {
      colorUpdateTimer = wrap(colorUpdateTimer, 0, 1);
      pointers.forEach(p => {
        p.color = generateColor();
      });
    }
  }

  function applyInputs() {
    pointers.forEach(p => {
      if (p.moved) {
        p.moved = false;
        splatPointer(p);
      }
    });
  }

  function step(dt) {
    gl.disable(gl.BLEND);
    curlProgram.bind();
    gl.uniform2f(curlProgram.uniforms.texelSize, velocity.texelSizeX, velocity.texelSizeY);
    gl.uniform1i(curlProgram.uniforms.uVelocity, velocity.read.attach(0));
    blit(curl);

    vorticityProgram.bind();
    gl.uniform2f(vorticityProgram.uniforms.texelSize, velocity.texelSizeX, velocity.texelSizeY);
    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);
    velocity.swap();

    divergenceProgram.bind();
    gl.uniform2f(divergenceProgram.uniforms.texelSize, velocity.texelSizeX, velocity.texelSizeY);
    gl.uniform1i(divergenceProgram.uniforms.uVelocity, velocity.read.attach(0));
    blit(divergence);

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

    pressureProgram.bind();
    gl.uniform2f(pressureProgram.uniforms.texelSize, velocity.texelSizeX, velocity.texelSizeY);
    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);
      pressure.swap();
    }

    gradienSubtractProgram.bind();
    gl.uniform2f(gradienSubtractProgram.uniforms.texelSize, velocity.texelSizeX, velocity.texelSizeY);
    gl.uniform1i(gradienSubtractProgram.uniforms.uPressure, pressure.read.attach(0));
    gl.uniform1i(gradienSubtractProgram.uniforms.uVelocity, velocity.read.attach(1));
    blit(velocity.write);
    velocity.swap();

    advectionProgram.bind();
    gl.uniform2f(advectionProgram.uniforms.texelSize, velocity.texelSizeX, velocity.texelSizeY);
    if (!ext.supportLinearFiltering)
      gl.uniform2f(advectionProgram.uniforms.dyeTexelSize, velocity.texelSizeX, velocity.texelSizeY);
    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);
    velocity.swap();

    if (!ext.supportLinearFiltering)
      gl.uniform2f(advectionProgram.uniforms.dyeTexelSize, dye.texelSizeX, dye.texelSizeY);
    gl.uniform1i(advectionProgram.uniforms.uVelocity, velocity.read.attach(0));
    gl.uniform1i(advectionProgram.uniforms.uSource, dye.read.attach(1));
    gl.uniform1f(advectionProgram.uniforms.dissipation, config.DENSITY_DISSIPATION);
    blit(dye.write);
    dye.swap();
  }

  function render(target) {
    gl.blendFunc(gl.ONE, gl.ONE_MINUS_SRC_ALPHA);
    gl.enable(gl.BLEND);
    drawDisplay(target);
  }

  function drawDisplay(target) {
    let width = target == null ? gl.drawingBufferWidth : target.width;
    let height = target == null ? gl.drawingBufferHeight : target.height;
    displayMaterial.bind();
    if (config.SHADING) gl.uniform2f(displayMaterial.uniforms.texelSize, 1.0 / width, 1.0 / height);
    gl.uniform1i(displayMaterial.uniforms.uTexture, dye.read.attach(0));
    blit(target);
  }

  function splatPointer(pointer) {
    let dx = pointer.deltaX * config.SPLAT_FORCE;
    let dy = pointer.deltaY * config.SPLAT_FORCE;
    splat(pointer.texcoordX, pointer.texcoordY, dx, dy, pointer.color);
  }

  function clickSplat(pointer) {
    const color = generateColor();
    color.r *= 10.0;
    color.g *= 10.0;
    color.b *= 10.0;
    let dx = 10 * (Math.random() - 0.5);
    let dy = 30 * (Math.random() - 0.5);
    splat(pointer.texcoordX, pointer.texcoordY, dx, dy, color);
  }

  function splat(x, y, dx, dy, color) {
    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, y);
    gl.uniform3f(splatProgram.uniforms.color, dx, dy, 0.0);
    gl.uniform1f(splatProgram.uniforms.radius, correctRadius(config.SPLAT_RADIUS / 100.0));
    blit(velocity.write);
    velocity.swap();

    gl.uniform1i(splatProgram.uniforms.uTarget, dye.read.attach(0));
    gl.uniform3f(splatProgram.uniforms.color, color.r, color.g, color.b);
    blit(dye.write);
    dye.swap();
  }

  function correctRadius(radius) {
    let aspectRatio = canvas.width / canvas.height;
    if (aspectRatio > 1) radius *= aspectRatio;
    return radius;
  }

  function updatePointerDownData(pointer, id, posX, posY) {
    pointer.id = id;
    pointer.down = true;
    pointer.moved = false;
    pointer.texcoordX = posX / canvas.width;
    pointer.texcoordY = 1.0 - posY / canvas.height;
    pointer.prevTexcoordX = pointer.texcoordX;
    pointer.prevTexcoordY = pointer.texcoordY;
    pointer.deltaX = 0;
    pointer.deltaY = 0;
    pointer.color = generateColor();
  }

  function updatePointerMoveData(pointer, posX, posY, color) {
    pointer.prevTexcoordX = pointer.texcoordX;
    pointer.prevTexcoordY = pointer.texcoordY;
    pointer.texcoordX = posX / canvas.width;
    pointer.texcoordY = 1.0 - posY / canvas.height;
    pointer.deltaX = correctDeltaX(pointer.texcoordX - pointer.prevTexcoordX);
    pointer.deltaY = correctDeltaY(pointer.texcoordY - pointer.prevTexcoordY);
    pointer.moved = Math.abs(pointer.deltaX) > 0 || Math.abs(pointer.deltaY) > 0;
    pointer.color = color;
  }

  function updatePointerUpData(pointer) {
    pointer.down = false;
  }

  function correctDeltaX(delta) {
    let aspectRatio = canvas.width / canvas.height;
    if (aspectRatio < 1) delta *= aspectRatio;
    return delta;
  }

  function correctDeltaY(delta) {
    let aspectRatio = canvas.width / canvas.height;
    if (aspectRatio > 1) delta /= aspectRatio;
    return delta;
  }

  function hexToRGB(hex) {
    let val = hex.replace('#', '');
    if (val.length === 3) val = val[0] + val[0] + val[1] + val[1] + val[2] + val[2];
    const r = parseInt(val.slice(0, 2), 16) / 255;
    const g = parseInt(val.slice(2, 4), 16) / 255;
    const b = parseInt(val.slice(4, 6), 16) / 255;
    return { r: r * 0.15, g: g * 0.15, b: b * 0.15 };
  }

  function generateColor() {
    if (!config.RAINBOW_MODE) {
      return hexToRGB(config.COLOR);
    }
    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;
      default: break;
    }
    return { r, g, b };
  }

  function wrap(value, min, max) {
    const range = max - min;
    if (range === 0) return min;
    return ((value - min) % range) + min;
  }

  function getResolution(resolution) {
    let aspectRatio = gl.drawingBufferWidth / gl.drawingBufferHeight;
    if (aspectRatio < 1) aspectRatio = 1.0 / aspectRatio;
    const min = Math.round(resolution);
    const max = Math.round(resolution * aspectRatio);
    if (gl.drawingBufferWidth > gl.drawingBufferHeight) return { width: max, height: min };
    else return { width: min, height: max };
  }

  function scaleByPixelRatio(input) {
    const pixelRatio = window.devicePixelRatio || 1;
    return Math.floor(input * pixelRatio);
  }

  function hashCode(s) {
    if (s.length === 0) return 0;
    let hash = 0;
    for (let i = 0; i < s.length; i++) {
      hash = (hash << 5) - hash + s.charCodeAt(i);
      hash |= 0;
    }
    return hash;
  }

  function handleMouseDown(e) {
    let pointer = pointers[0];
    let posX = scaleByPixelRatio(e.clientX);
    let posY = scaleByPixelRatio(e.clientY);
    updatePointerDownData(pointer, -1, posX, posY);
    clickSplat(pointer);
  }

  let firstMouseMoveHandled = false;
  function handleMouseMove(e) {
    let pointer = pointers[0];
    let posX = scaleByPixelRatio(e.clientX);
    let posY = scaleByPixelRatio(e.clientY);
    if (!firstMouseMoveHandled) {
      let color = generateColor();
      updatePointerMoveData(pointer, posX, posY, color);
      firstMouseMoveHandled = true;
    } else {
      updatePointerMoveData(pointer, posX, posY, pointer.color);
    }
  }

  function handleTouchStart(e) {
    const touches = e.targetTouches;
    let pointer = pointers[0];
    for (let i = 0; i < touches.length; i++) {
      let posX = scaleByPixelRatio(touches[i].clientX);
      let posY = scaleByPixelRatio(touches[i].clientY);
      updatePointerDownData(pointer, touches[i].identifier, posX, posY);
    }
  }

  function handleTouchMove(e) {
    const touches = e.targetTouches;
    let pointer = pointers[0];
    for (let i = 0; i < touches.length; i++) {
      let posX = scaleByPixelRatio(touches[i].clientX);
      let posY = scaleByPixelRatio(touches[i].clientY);
      updatePointerMoveData(pointer, posX, posY, pointer.color);
    }
  }

  function handleTouchEnd(e) {
    const touches = e.changedTouches;
    let pointer = pointers[0];
    for (let i = 0; i < touches.length; i++) {
      updatePointerUpData(pointer);
    }
  }

  window.addEventListener('mousedown', handleMouseDown);
  window.addEventListener('mousemove', handleMouseMove);
  window.addEventListener('touchstart', handleTouchStart);
  window.addEventListener('touchmove', handleTouchMove, {passive: false});
  window.addEventListener('touchend', handleTouchEnd);

  updateFrame();

  return function destroy() {
    isActive = false;
    if (animationFrameId) {
      cancelAnimationFrame(animationFrameId);
    }
    window.removeEventListener('mousedown', handleMouseDown);
    window.removeEventListener('mousemove', handleMouseMove);
    window.removeEventListener('touchstart', handleTouchStart);
    window.removeEventListener('touchmove', handleTouchMove);
    window.removeEventListener('touchend', handleTouchEnd);
    if(container && document.body.contains(container)) {
        document.body.removeChild(container);
    }
  };
}
