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<canvas id="webgl" width="500" height="1758"></canvas>
<script id="vertexShader" type="x-shader/x-vertex">
attribute vec4 a_position;
uniform mat4 u_modelViewMatrix;
uniform mat4 u_projectionMatrix;
void main() {
gl_Position = a_position;
}
</script>
<script id="fragmentShader" type="x-shader/x-fragment">
precision highp float;
uniform vec2 u_resolution;
uniform vec2 u_mouse;
uniform float u_time;
uniform sampler2D u_noise;
uniform sampler2D u_buffer;
uniform bool u_bufferpass;
#define PI 3.14159265359
#define TAU 6.28318530718
// These awesome complex Math functions curtesy of
// https://github.com/mkovacs/reim/blob/master/reim.glsl
vec2 cCis(float r);
vec2 cLog(vec2 c); // principal value
vec2 cInv(vec2 c);
float cArg(vec2 c);
float cAbs(vec2 c);
vec2 cMul(vec2 a, vec2 b);
vec2 cDiv(vec2 a, vec2 b);
vec2 cCis(float r)
{
return vec2( cos(r), sin(r) );
}
vec2 cExp(vec2 c)
{
return exp(c.x) * cCis(c.y);
}
vec2 cConj(vec2 c)
{
return vec2(c.x, -c.y);
}
vec2 cInv(vec2 c)
{
return cConj(c) / dot(c, c);
}
vec2 cLog(vec2 c)
{
return vec2( log( cAbs(c) ), cArg(c) );
}
float cArg(vec2 c)
{
return atan(c.y, c.x);
}
float cAbs(vec2 c)
{
return length(c);
}
vec2 cMul(vec2 a, vec2 b)
{
return vec2(a.x*b.x - a.y*b.y, a.x*b.y + a.y*b.x);
}
vec2 cDiv(vec2 a, vec2 b)
{
return cMul(a, cInv(b));
}
float r1 = 0.1;
float r2 = 0.3;
vec2 Droste(vec2 uv) {
r1 = .1 + clamp(u_mouse.x * .5, -.05, .5);
r2 = .15 + clamp(u_mouse.y * .5 + .5, -.05, .3);
if(r1 >= r2) r1 = r2 - .1;
// float c = cos(u_time);
// float s = sin(u_time);
// uv *= mat2(c, -s, s, c);
// 5. Take the tiled strips back to ordinary space.
uv = cLog(uv);
// 4. Scale and rotate the strips
float scale = log(r2/r1);
float angle = atan(scale/PI);
uv = cDiv(uv, cExp(vec2(0,angle))*cos(angle));
// 3. this simulates zooming in the tile
// uv -= u_time;
// 2. Tile the strips
uv.x = mod(uv.x,log(r2/r1));
// 1. Take the annulus to a strip
uv = cExp(uv)*r1;
return uv;
}
vec3 hash3( vec2 p ) {
vec3 q = vec3( dot(p,vec2(127.1,311.7)),
dot(p,vec2(269.5,183.3)),
dot(p,vec2(419.2,371.9)) );
return fract(sin(q)*43758.5453);
}
vec2 getScreenSpace() {
vec2 uv = (gl_FragCoord.xy - 0.5 * u_resolution.xy) / min(u_resolution.y, u_resolution.x);
return uv;
}
const float colours = 3.;
const vec4 colour1 = vec4(.1,.2,.8, 1.);
const vec4 colour2 = vec4(.8,.3,.2, 1.);
const vec4 colour3 = vec4(.1,.7,.2, 1.);
vec4 getColour(float r) {
float or = r;
r = floor(r*(colours+1.));
if(r == 0.) {
return colour1;
} else if(r == 1.) {
return colour2+vec4(0, (sin(u_time*3. + or*10.) * or + or), 0., 0.);
} else if(r == 2.) {
return colour3;
}
}
vec4 render(vec2 uv) {
// uv *= 10.;
// uv.x += u_time;
float row = floor(uv.y);
if(mod(row, 2.) == 0.) return vec4(0,0,0,1);
vec4 rowval = texture2D(u_noise, vec2(.5, row/200.));
float nf = rowval.r;
nf *= nf;
nf *= 5.;
uv.x += u_time * nf * 3.;
float noiseloopval = sin(uv.x*PI*.1)*floor(uv.y);
noiseloopval = mod(uv.x*row, row*2.);
vec2 uvid = floor(vec2( noiseloopval, uv.y ));
vec3 uvseed = hash3(uvid/PI);
vec4 colour = vec4(1.);
colour = getColour(rowval.g);
colour *= uvseed.x * (sin(u_time * 20. + uvseed.y*100.) * .5 + .5) * (uvseed.z+.5);
return mix(vec4(0,0,0,1), colour, colour.a);
}
vec4 render_effect(vec2 uv) {
vec2 polar = vec2(atan(uv.x, uv.y)/PI, length(uv));
vec4 c = render(polar);
c += render(polar * vec2(2., .6) + vec2(0.,1./.6));
c += render(polar * vec2(1., 1.2) + vec2(0.,1./1.2));
uv = Droste(getScreenSpace()*.5)*10.;
polar = vec2(atan(uv.x, uv.y)/PI, length(uv));
c += render(polar * vec2(1., 2.2) + vec2(0.,2./2.2));
return c;
}
void main() {
vec4 prev = texture2D(u_buffer, gl_FragCoord.xy/u_resolution);
if(u_bufferpass) {
vec2 uv = Droste(getScreenSpace())*50.;
gl_FragColor = prev * .8 + render_effect(uv) * .2;
} else {
gl_FragColor = prev;
}
}
</script>
body {
margin:0;
}
canvas {
position: fixed;
}
console.clear();
w = 1024;
w = 1024;
const twodWebGL = new WTCGL(
document.querySelector('canvas#webgl'),
document.querySelector('script#vertexShader').textContent,
document.querySelector('script#fragmentShader').textContent,
window.innerWidth,
window.innerHeight,
2
);
twodWebGL.startTime = -100 + Math.random() * 50;
let fb1 = twodWebGL.addFrameBuffer(window.innerWidth, window.innerHeight, WTCGL.IMAGETYPE_REGULAR, WTCGL.TEXTYPE_HALF_FLOAT_OES);
let fb2 = twodWebGL.addFrameBuffer(window.innerWidth, window.innerHeight, WTCGL.IMAGETYPE_REGULAR, WTCGL.TEXTYPE_HALF_FLOAT_OES);
let activeFB = fb1;
let timeout;
window.addEventListener('resize', () => {
clearTimeout(timeout);
timeout = setTimeout(() => {
twodWebGL.resize(window.innerWidth, window.innerHeight);
fb1 = twodWebGL.addFrameBuffer(window.innerWidth, window.innerHeight, WTCGL.IMAGETYPE_REGULAR, WTCGL.TEXTYPE_HALF_FLOAT_OES);
fb2 = twodWebGL.addFrameBuffer(window.innerWidth, window.innerHeight, WTCGL.IMAGETYPE_REGULAR, WTCGL.TEXTYPE_HALF_FLOAT_OES);
}, 100);
});
twodWebGL.onRun = (delta) => {
let _ctx = twodWebGL._ctx;
// find the active texture based on the index
uniform = _ctx.getUniformLocation(twodWebGL._program, `u_buffer`);
// Set the texture unit to the uniform
_ctx.uniform1i(uniform, 5);
_ctx.activeTexture(_ctx.TEXTURE5);
// Finally, bind the texture
_ctx.bindTexture(_ctx.TEXTURE_2D, activeFB.frameTexture);
activeFB = activeFB === fb1 ? fb2 : fb1;
twodWebGL.addUniform('bufferpass', WTCGL.TYPE_BOOL, true);
// twodWebGL.resize(1024, 1024);
twodWebGL.render(activeFB);
twodWebGL.addUniform('bufferpass', WTCGL.TYPE_BOOL, false);
// twodWebGL.resize(window.innerWidth, window.innerHeight);
oldmousepos[0] += (mousepos[0] - oldmousepos[0])*.02;
oldmousepos[1] += (mousepos[1] - oldmousepos[1])*.02;
// oldmousepos = mousepos;
twodWebGL.addUniform('mouse', WTCGL.TYPE_V2, oldmousepos);
}
// track mouse move
let oldmousepos = [0,0];
let mousepos = [0,0];
const u_mousepos = twodWebGL.addUniform('mouse', WTCGL.TYPE_V2, mousepos);
window.addEventListener('pointermove', (e) => {
let ratio = window.innerHeight / window.innerWidth;
if(window.innerHeight > window.innerWidth) {
mousepos[0] = (e.pageX - window.innerWidth / 2) / window.innerWidth;
mousepos[1] = (e.pageY - window.innerHeight / 2) / window.innerHeight * -1 * ratio;
} else {
mousepos[0] = (e.pageX - window.innerWidth / 2) / window.innerWidth / ratio;
mousepos[1] = (e.pageY - window.innerHeight / 2) / window.innerHeight * -1;
}
});
// Load all our textures. We only initiate the instance once all images are loaded.
const textures = [
{
name: 'noise',
url: 'https://s3-us-west-2.amazonaws.com/s.cdpn.io/982762/noise.png',
type: WTCGL.IMAGETYPE_TILE,
img: null
}
];
const loadImage = function (imageObject) {
let img = document.createElement('img');
img.crossOrigin="anonymous";
return new Promise((resolve, reject) => {
img.addEventListener('load', (e) => {
imageObject.img = img;
resolve(imageObject);
});
img.addEventListener('error', (e) => {
reject(e);
});
img.src = imageObject.url
});
}
const loadTextures = function(textures) {
return new Promise((resolve, reject) => {
const loadTexture = (pointer) => {
if(pointer >= textures.length || pointer > 10) {
resolve(textures);
return;
};
const imageObject = textures[pointer];
const p = loadImage(imageObject);
p.then(
(result) => {
twodWebGL.addTexture(result.name, result.type, result.img);
},
(error) => {
console.log('error', error)
}).finally((e) => {
loadTexture(pointer+1);
});
}
loadTexture(0);
});
}
loadTextures(textures).then(
(result) => {
twodWebGL.initTextures();
// twodWebGL.render();
twodWebGL.running = true;
},
(error) => {
console.log('error');
}
);
Also see: Tab Triggers