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<!-- this pen was built and maintained in https://github.com/callumacrae/sketchbook/blob/master/src/views/ParticlePhotoWebgl.vue -->
<p class="loading">loading…</p>
<div class="canvas-container" style="display: none">
<canvas
ref="canvas"
@click="status = status === 'playing' ? 'paused' : 'playing'"
@dragenter.prevent
@dragleave.prevent
@dragover.prevent
@drop.prevent="handleDrop"
></canvas>
<GlobalEvents target="window" @resize="setSize" />
<div class="help-container" v-show="showHelp || showIosWarning">
<div class="help" v-show="showIosWarning">
<h2 style="color: red">WARNING</h2>
<p>
Due to a bug in how iOS handles webgl instancing, this animation
performs incredibly poorly on iOS—to the point where it doesn't really
work at all. On my phone, it runs at 0.0075 fps and makes my phone
heat up to the temperature of the sun.
</p>
<p>
I'd recommend trying this on desktop (it also just looks better), but
if you really want to see what happens on iOS, you can
<a
href
@click.prevent="
showIosWarning = false;
status = 'playing';
"
>
proceed anyway</a
>.
</p>
</div>
<div class="help" v-show="showHelp">
<h2>Instructions</h2>
<p>
This experiment visualises images as collections of animated coloured
particles.
</p>
<p>
In addition to providing a few images (selectable on the configuration
in the top right of the screen), it also allows you to upload your own
by dragging and dropping them onto the canvas.
</p>
<p>
Through a bit of experimentation, I've found the following makes the
best images:
</p>
<ul>
<li>
Lower resolution images or blurred images work better as it prevents
the particles from changing size and colour too quickly as they move
about. Most of the demo images are lower than 500px wide.
</li>
<li>
Images with lots of contrast between lighter and darker areas make
more effective graphics. Similarly, images where the details are on
the lighter parts of the images and the backgrounds are dark also
look better.
</li>
<li>
Some images, especially images with finer details, look better with
a high number of smaller points (adjust pointSizeMultiplier), while
others look better with a low number of larger points.
</li>
</ul>
<p>
To export high quality videos from this you'll need to
<a href="https://github.com/callumacrae/sketchbook">clone the repo</a>
and look for the <code>this.record</code> call in
ParticlePhotoWebgl.vue (or ask me for help on Twitter!)
</p>
</div>
</div>
<p class="status" v-show="status === 'paused' && !showIosWarning" @click="status = 'playing'">
paused, click to resume
</p>
<a
v-if="!showIosWarning"
class="toggle-help-link"
href
@click.prevent="showHelp = !showHelp"
>
toggle help
</a>
</div>
<script type="nojs" id="vs">
precision mediump float;
//
// Description : Array and textureless GLSL 2D simplex noise function.
// Author : Ian McEwan, Ashima Arts.
// Maintainer : stegu
// Lastmod : 20110822 (ijm)
// License : Copyright (C) 2011 Ashima Arts. All rights reserved.
// Distributed under the MIT License. See LICENSE file.
// https://github.com/ashima/webgl-noise
// https://github.com/stegu/webgl-noise
//
vec3 mod289(vec3 x) {
return x - floor(x * (1.0 / 289.0)) * 289.0;
}
vec2 mod289(vec2 x) {
return x - floor(x * (1.0 / 289.0)) * 289.0;
}
vec3 permute(vec3 x) {
return mod289(((x*34.0)+10.0)*x);
}
float noise2d(vec2 v)
{
const vec4 C = vec4(0.211324865405187, // (3.0-sqrt(3.0))/6.0
0.366025403784439, // 0.5*(sqrt(3.0)-1.0)
-0.577350269189626, // -1.0 + 2.0 * C.x
0.024390243902439); // 1.0 / 41.0
// First corner
vec2 i = floor(v + dot(v, C.yy) );
vec2 x0 = v - i + dot(i, C.xx);
// Other corners
vec2 i1;
//i1.x = step( x0.y, x0.x ); // x0.x > x0.y ? 1.0 : 0.0
//i1.y = 1.0 - i1.x;
i1 = (x0.x > x0.y) ? vec2(1.0, 0.0) : vec2(0.0, 1.0);
// x0 = x0 - 0.0 + 0.0 * C.xx ;
// x1 = x0 - i1 + 1.0 * C.xx ;
// x2 = x0 - 1.0 + 2.0 * C.xx ;
vec4 x12 = x0.xyxy + C.xxzz;
x12.xy -= i1;
// Permutations
i = mod289(i); // Avoid truncation effects in permutation
vec3 p = permute( permute( i.y + vec3(0.0, i1.y, 1.0 ))
+ i.x + vec3(0.0, i1.x, 1.0 ));
vec3 m = max(0.5 - vec3(dot(x0,x0), dot(x12.xy,x12.xy), dot(x12.zw,x12.zw)), 0.0);
m = m*m ;
m = m*m ;
// Gradients: 41 points uniformly over a line, mapped onto a diamond.
// The ring size 17*17 = 289 is close to a multiple of 41 (41*7 = 287)
vec3 x = 2.0 * fract(p * C.www) - 1.0;
vec3 h = abs(x) - 0.5;
vec3 ox = floor(x + 0.5);
vec3 a0 = x - ox;
// Normalise gradients implicitly by scaling m
// Approximation of: m *= inversesqrt( a0*a0 + h*h );
m *= 1.79284291400159 - 0.85373472095314 * ( a0*a0 + h*h );
// Compute final noise value at P
vec3 g;
g.x = a0.x * x0.x + h.x * x0.y;
g.yz = a0.yz * x12.xz + h.yz * x12.yw;
return 130.0 * dot(m, g);
}
attribute float a_x;
attribute float a_initial_offset;
attribute float a_speed;
uniform float u_time;
uniform sampler2D u_image_texture;
uniform float u_width;
uniform float u_x_in_noise_multiplier;
uniform float u_x_out_noise_multiplier;
uniform float u_y_in_noise_multiplier;
uniform float u_y_out_noise_multiplier;
uniform float u_point_size_multiplier;
varying vec2 v_position;
varying float v_initial_offset;
void main() {
vec2 position = vec2(2.0 * a_x - 1.0, 0.0);
float offset_y = mod(a_initial_offset + 1.0 + a_speed * u_time / 500000.0, 2.0) - 1.0;
position.x += noise2d(
vec2(a_x * u_x_in_noise_multiplier + 123.4, offset_y * 0.5 + u_time / 100000.0)
) * u_x_out_noise_multiplier;
position.y += offset_y + noise2d(
vec2(a_x * u_y_in_noise_multiplier, u_time / 10000.0 + 100.0)
) * u_y_out_noise_multiplier;
position.y *= 1.1;
v_position = position;
v_initial_offset = a_initial_offset;
gl_Position = vec4(position, 0.0, 1.0);
gl_PointSize = u_width / 660.0 * u_point_size_multiplier;
}
</script>
<script type="nojs" id="fs">
precision mediump float;
uniform sampler2D u_image_texture;
uniform float u_radius_val_exponent;
uniform float u_alpha_val_exponent;
uniform float u_alpha_val_multiplier;
uniform bool u_color;
uniform float u_twinkle_frequency;
uniform float u_twinkle_intensity;
uniform float u_twinkle_factor;
varying vec2 v_position;
varying float v_initial_offset;
void main() {
vec2 position = v_position;
position.y *= -1.0;
vec4 texture_color = texture2D(u_image_texture, (position + 1.0) / 2.0);
// http://www.johndcook.com/blog/2009/08/24/algorithms-convert-color-grayscale/
// The alpha multiplication stops random transparent white pixels from ruining everything
float intensity = (0.21 * texture_color.r + 0.71 * texture_color.g + 0.07 * texture_color.b) * texture_color.a;
float radius_val = pow(intensity, u_radius_val_exponent);
float alpha_val = pow(intensity, u_alpha_val_exponent) * u_alpha_val_multiplier;
float twinkle_y_normalised = abs(mod((position.y - v_initial_offset * 123.0) * 100.0, u_twinkle_frequency * 2.0) - u_twinkle_frequency);
float twinkle_value = 1.0 - u_twinkle_factor + u_twinkle_factor * smoothstep(
u_twinkle_frequency * (1.0 - 1.0 / u_twinkle_intensity / u_twinkle_frequency * 5.0),
u_twinkle_frequency,
twinkle_y_normalised
);
vec2 pc = (gl_PointCoord - 0.5) * 2.0;
float dist = sqrt(pc.x * pc.x + pc.y * pc.y);
float alpha = alpha_val * smoothstep(radius_val, radius_val - 0.1, dist) * twinkle_value;
gl_FragColor = vec4(u_color ? texture_color.rgb : vec3(1.0), alpha);
}
</script>
body {
margin: 0;
background-color: black;
}
.loading {
color: white;
}
.canvas-container {
width: 100vw;
height: 100vh;
display: flex;
align-items: center;
justify-content: center;
font-family: sans-serif;
background-color: black;
}
canvas {
max-height: 100vh;
max-width: 100vw;
}
.toggle-help-link {
position: absolute;
bottom: 10px;
right: 10px;
font-size: 12px;
text-decoration: none;
color: lightgrey;
}
.status {
position: absolute;
bottom: 10px;
left: 10px;
font-size: 12px;
color: lightgrey;
}
.help-container {
position: fixed;
left: 0;
top: 0;
right: 0;
bottom: 0;
display: flex;
align-items: center;
justify-content: center;
background-color: rgba(0, 0, 0, 0.4);
color: white;
backdrop-filter: blur(3px);
}
.help-container .help {
width: 90%;
max-width: 500px;
}
.help li {
margin-bottom: 1em;
}
.help a {
color: inherit;
}
import * as twgl from 'https://cdn.skypack.dev/twgl.js@4/dist/4.x/twgl-full.module';
import * as dat from 'https://cdn.skypack.dev/dat.gui';
import Stats from 'https://cdn.skypack.dev/stats.js';
import * as random from 'https://cdn.skypack.dev/@callumacrae/utils@0.2.4/built/random';
// This is mostly for displaying warnings
const isAndroid = /android/i.test(navigator.userAgent);
const isIos = /iPad|iPhone|iPod/.test(navigator.userAgent) && !window.MSStream;
const isMobile = isAndroid || isIos;
const imageData = {
sunset: {
src:
'https://sketchbook.macr.ae/assets/particle-photos/leo-nagle-TLuNQu-5xP4-unsplash-small-blurred.jpg',
ratio: 2 / 3,
configPreset: {
particles: isMobile ? 20e3 : 40e3,
color: true,
radiusValExponent: 1.5,
alphaValMultiplier: 0.85,
alphaValExponent: 1.2,
pointSizeMultiplier: isMobile ? 20 : 10,
twinkleFactor: 0
}
},
woman: {
src:
'https://sketchbook.macr.ae/assets/particle-photos/thea-hoyer-CrJyu9HoeBg-unsplash-small-blurred.jpg',
ratio: 2 / 3,
configPreset: {
color: false,
particles: 30e3,
radiusValExponent: 2,
alphaValExponent: 1.5,
alphaValMultiplier: 0.85,
pointSizeMultiplier: 10,
twinkleFactor: 0
}
},
zebra: {
src:
'https://sketchbook.macr.ae/assets/particle-photos/frida-bredesen-c_cPNXlovvY-unsplash-small-blurred.png',
ratio: 1,
configPreset: {
color: false,
particles: 30e3,
radiusValExponent: 2,
alphaValExponent: 1.5,
alphaValMultiplier: 1,
pointSizeMultiplier: 10,
twinkleFrequency: 12,
twinkleIntensity: 25,
twinkleFactor: 0.7
}
},
'bucket hat': {
src: 'https://sketchbook.macr.ae/assets/particle-photos/brandon-webb-FwjkcL9Hpx8-unsplash-small.jpg',
ratio: 3 / 2,
configPreset: {
color: true,
radiusValExponent: 0.7,
alphaValExponent: 0.7,
alphaValMultiplier: 1,
pointSizeMultiplier: 7,
twinkleFactor: 0
}
},
rhino: {
src: 'https://sketchbook.macr.ae/assets/particle-photos/rhino.jpeg',
ratio: 422 / 222,
configPreset: {
particles: 50e3,
radiusValExponent: 1.3,
alphaValExponent: 0.1,
alphaValMultiplier: 1,
color: true,
pointSizeMultiplier: 8,
twinkleFactor: 0.7
}
}
};
new Vue({
el: '.canvas-container',
data: () => {
const image = 'rhino';
return {
status: 'playing',
width: undefined,
height: undefined,
showHelp: false,
showIosWarning: false,
userTexture: undefined,
config: {
// Init config
particles: 40e3,
particleBaseSpeed: isMobile ? 8 : 5,
// Shader config
radiusValExponent: 1.5,
alphaValExponent: 1.2,
alphaValMultiplier: 0.85,
color: true,
xInNoiseMultiplier: 200, // Not user configurable, bit buggy
xOutNoiseMultiplier: isMobile ? 0.4 : 0.2,
yInNoiseMultiplier: 1234, // Not user configurable, pointless
yOutNoiseMultiplier: isMobile ? 0.004 : 0.002,
pointSizeMultiplier: 10,
twinkleFrequency: 12,
twinkleIntensity: 25,
twinkleFactor: 0,
image,
...imageData[image].configPreset
}
};
},
mounted() {
document.querySelector('.loading').style.display = 'none';
this.$el.style.display = 'flex';
this.setSize();
this.init().then(() => {
this.frame();
});
const gui = new dat.GUI();
this.gui = gui;
gui
.add(this.config, 'image', Object.keys(imageData).concat('user'))
.listen();
gui.add(this.config, 'particles', 5000, 100000, 1000).listen();
gui.add(this.config, 'particleBaseSpeed', 0, 50).listen();
gui.add(this.config, 'radiusValExponent', 0.1, 10).listen();
gui.add(this.config, 'alphaValExponent', 0.1, 10).listen();
gui.add(this.config, 'alphaValMultiplier', 0.1, 1).listen();
gui.add(this.config, 'color').listen();
gui.add(this.config, 'xOutNoiseMultiplier', 0, 1).listen();
gui.add(this.config, 'yOutNoiseMultiplier', 0, 0.1).listen();
gui.add(this.config, 'pointSizeMultiplier', 1, 30).listen();
gui.add(this.config, 'twinkleFrequency', 1, 50).listen();
gui.add(this.config, 'twinkleIntensity', 1, 50).listen();
gui.add(this.config, 'twinkleFactor', 0, 1).listen();
this.stats = new Stats();
this.stats.showPanel(0); // 0: fps, 1: ms, 2: mb, 3+: custom
document.body.appendChild(this.stats.dom);
if (isIos) {
this.status = 'paused';
this.showIosWarning = true;
gui.close();
}
},
beforeDestroy() {
cancelAnimationFrame(this.frameId);
if (this.gui) {
this.gui.destroy();
}
if (this.stats) {
this.stats.dom.remove();
delete this.stats;
}
},
methods: {
setSize() {
const canvas = this.$refs.canvas;
this.gl = canvas.getContext('webgl', { preserveDrawingBuffer: true });
this.dpr = window.devicePixelRatio;
if (window.innerWidth < window.innerHeight * this.imageData.ratio) {
this.width = window.innerWidth * this.dpr;
this.height = (window.innerWidth / this.imageData.ratio) * this.dpr;
} else {
this.height = window.innerHeight * this.dpr;
this.width = window.innerHeight * this.imageData.ratio * this.dpr;
}
canvas.width = this.width;
canvas.height = this.height;
},
init() {
const { gl, config } = this;
gl.enable(gl.BLEND);
gl.blendFunc(gl.SRC_ALPHA, gl.ONE_MINUS_SRC_ALPHA);
this.programInfo = twgl.createProgramInfo(gl, ['vs', 'fs']);
const particleData = {
xs: [],
initialOffsets: [],
speeds: []
};
for (let i = 0; i < config.particles; i++) {
particleData.xs.push(i / config.particles);
particleData.initialOffsets.push(random.range(-1, 1));
particleData.speeds.push(random.range(0, config.particleBaseSpeed));
}
this.particleData = particleData;
twgl.setAttributePrefix('a_');
this.bufferInfo = twgl.createBufferInfoFromArrays(gl, {
x: {
numComponents: 1,
data: particleData.xs
},
initial_offset: {
numComponents: 1,
data: particleData.initialOffsets
},
speed: {
numComponents: 1,
data: particleData.speeds
}
});
twgl.setBuffersAndAttributes(gl, this.programInfo, this.bufferInfo);
if (this.images) {
return Promise.resolve();
}
return new Promise(resolve => {
// Use a blurred image instead of sampling an area of more than one pixel
// in the fragment shader - do the work ahead of time!
this.images = twgl.createTextures(gl, imageData, resolve);
});
},
frame(timestamp = 0) {
if (this.status !== 'recording') {
this.frameId = requestAnimationFrame(this.frame);
}
if (this.status === 'paused') {
return;
}
this.stats.begin();
const { gl, programInfo, bufferInfo, width, height, config } = this;
gl.viewport(0, 0, width, height);
gl.useProgram(programInfo.program);
gl.clear(gl.COLOR_BUFFER_BIT);
const uniforms = {
u_time: timestamp,
u_image_texture:
config.image === 'user'
? this.userTexture.texture
: this.images[config.image],
u_width: width,
u_height: height,
u_dpr: this.dpr,
u_radius_val_exponent: config.radiusValExponent,
u_alpha_val_exponent: config.alphaValExponent,
u_alpha_val_multiplier: config.alphaValMultiplier,
u_color: config.color,
u_x_in_noise_multiplier: config.xInNoiseMultiplier,
u_x_out_noise_multiplier: config.xOutNoiseMultiplier,
u_y_in_noise_multiplier: config.yInNoiseMultiplier,
u_y_out_noise_multiplier: config.yOutNoiseMultiplier,
u_point_size_multiplier: config.pointSizeMultiplier,
u_twinkle_frequency: config.twinkleFrequency,
u_twinkle_intensity: config.twinkleIntensity,
u_twinkle_factor: config.twinkleFactor
};
twgl.setUniforms(programInfo, uniforms);
twgl.drawBufferInfo(gl, bufferInfo, gl.POINTS);
this.stats.end();
},
handleDrop(e) {
const image = e.dataTransfer.files[0];
if (!image.type.startsWith('image/')) {
return;
}
const reader = new FileReader();
reader.onload = () => {
const img = document.createElement('img');
img.onload = () => {
const texture = twgl.createTexture(this.gl, { src: img });
this.userTexture = { texture, ratio: img.width / img.height };
this.config.image = 'user';
this.setSize();
if (img.width > 500 && img.height > 500) {
setTimeout(() => {
alert(
'Heads up, this works better with low resolution images: see the help for more info'
);
});
}
};
img.src = reader.result;
};
reader.readAsDataURL(image);
}
},
computed: {
imageData() {
return this.config.image === 'user'
? this.userTexture
: imageData[this.config.image];
}
},
watch: {
'config.particles': 'init',
'config.particleBaseSpeed': 'init',
'config.image'(image, oldImage) {
if (image === 'user' && !this.userTexture) {
alert('Drag and drop an image onto this window to test your own image');
this.config.image = oldImage;
return;
}
this.setSize();
if (this.imageData.configPreset) {
for (let [key, value] of Object.entries(this.imageData.configPreset)) {
this.config[key] = value;
}
}
}
}
});
Also see: Tab Triggers